rifampin and Tuberculosis--Multidrug-Resistant

At present, the number of cases with multidrug/rifampicin-resistant tuberculosis (MDR/RR-TB) in China ranks fourth in the world, and the prevention and control situation is still serious. Chemotherapy, as the most important treatment for MDR/RR-TB, was studied and explored by domestic and foreign researchers in 2022. New chemotherapeutic drugs such as delpazolid, sutezolid, telacebec and independently developed anti-tuberculosis drugs such as pyrifazimine, sudapyridine and JBD0131 are still in clinical trials. The efficacy, safety, tolerability, adverse reactions and drug resistance of bedaquiline, linezolid, delamanid and pretomanid have been studied extensively. Meanwhile, different new chemotherapy regimens centered on new drugs have been explored in-depth by international scholars. In this article, we reviewed the progress of chemotherapy of multidrug/rifampicin-resistant tuberculosis from October 2021 to September.. 目前，我国耐多药/利福平耐药结核病（MDR/RR-TB）的发病人数居世界第四位，防治形势依然十分严峻。化学治疗作为MDR/RR-TB治疗的最重要手段，国内外同道在2022年度对此进行了一系列研究和探索。化学治疗新药delpazolid、sutezolid、telacebec及我国自主研发的抗结核新药吡法齐明、舒达吡啶、JBD0131等尚处于临床试验阶段。对贝达喹啉、利奈唑胺、德拉马尼、普托马尼等已上市药物的有效性、安全性、耐受性、不良反应和耐药问题等进行了广泛的研究。同时，各国学者对以新药为核心的不同化学治疗新方案也进行了较为深入的探讨。本文就2021年10月至2022年9月的以上进展作一综述。.

Topics: Antitubercular Agents; Humans; Linezolid; Rifampin; Tuberculosis, Multidrug-Resistant

Tuberculosis (TB) continues to be a global public health issue that threatens human health, and rapid and accurate pathogen detection is the key to early diagnosis and effective treatment. In recent years, the pathogenic diagnosis of tuberculosis is expanding from traditional bacteriological diagnosis to molecular diagnosis. In the past year, Xper MTB/RIF Ultra technology with good diagnostic performance has been applied more often to the detection of non-respiratory samples, and Xpert XDR and second-generation linear probe technology provided more basis for early and accurate diagnosis of multidrug resistance; genome sequencing technology has also been developed and applied more often to the detection of non-culture sample detection, and the cost and time required for detection have been relatively reduced. Truenat technology, which is more suitable for primary care centers, is more widely used; new TB detection technologies, such as cell-free DNA testing and mass spectrometry, are also being developed and are expected to become important tools for early and rapid diagnosis of TB and drug-resistant TB. In this review, we synthesized the major research results of molecular biology diagnosis of tuberculosis around the world from 1. 结核病仍然是威胁人类健康的全球公共卫生问题，快速准确的病原体检测是实现早期诊断和有效治疗的关键。近年来，结核病的病原学诊断由传统的细菌学诊断向分子诊断扩展。近1年，具有良好诊断性能的Xper MTB/RIF Ultra技术更多被应用于非呼吸道样本的检测，Xpert XDR和二代线性探针技术为MDR-TB的早期快速准确诊断提供了更多依据；基因组测序技术也被更多开发应用于非培养物样本的检测，其检测成本和所需时间已相对降低和减少；更适合初级医疗保健中心开展的Truenat技术被更广泛应用；游离DNA检测及质谱检测等新型结核病检测技术同样不断发展，有望成为结核病及耐药结核病早期快速诊断的重要手段。本文综合2021年10月1日至2022年9月30日国内外结核病病原体分子生物学诊断的重要进展成果，评估分子生物学检测技术的优缺点及应用现状，为临床选择和应用提供重要依据。.

Topics: Antibiotics, Antitubercular; Drug Resistance, Bacterial; Humans; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

In December 2022 World Health Organization released a new treatment for multidrug-resistant/rifampicin-resistant tuberculosis (MDR/RR-TB) guideline. The main novelty of this update is two new recommendations (i) a 6-month treatment regimen composed of bedaquiline, pretomanid, linezolid (600 mg), and moxifloxacin (BPaLM) is recommended in place of the 9-month or longer (18-month) regimens in MDR/RR-TB patients, now including extensive pulmonary TB and extrapulmonary TB (except TB involving central nervous system, miliary TB and osteoarticular TB); (ii) the use of the 9-month all-oral regimen rather than longer (18-months) regimen is suggested in patients with MDR/RR-TB and in whom resistance to fluoroquinolones has been excluded. Longer (18-month) treatments remain a valid option in all cases in which shorter regimens cannot be implemented due to intolerance, drug-drug interactions, extensively drug-resistant tuberculosis, extensive forms of extrapulmonary TB, or previous failure. The new guidelines represent a milestone in MDR/RR-TB treatment landscape, setting the basis for a shorter, all-oral, more acceptable, equitable, and patient-centered model for MDR/RR-TB management. However, some challenges remain to be addressed to allow full implementation of the new recommendations.

Topics: Antitubercular Agents; Extensively Drug-Resistant Tuberculosis; Humans; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Tuberculosis (TB), caused by the bacillus

Topics: Antitubercular Agents; Ascorbic Acid; Humans; Latent Tuberculosis; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Reactive Oxygen Species; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant; Vitamins

Management of multidrug-resistant (MDR) and rifampin-resistant (RR) tuberculosis is challenging. Data on transplant recipients is limited. We reviewed published literature to examine treatment choices, outcomes, and adverse effects from MDR-TB/RR-TB treatment in transplant recipients.. Multiple databases from inception to 12/2022 were reviewed using the keywords "drug-resistant TB" or "drug-resistant tuberculosis" or "multidrug-resistant TB" or "multidrug-resistant tuberculosis". MDR-TB was defined as resistance to isoniazid (H) and rifampin (R), and RR if resistant to rifampin alone. Cases without patient-level data and reports which did not describe treatment and/or outcomes for MDR-TB were excluded.. A total of 12 patients (10 solid organ transplants and two hematopoietic cell transplants) were included. Of these, 11 were MDR-TB and one was RR-TB. Seven recipients were male. The median age was 41.5 (range 16-60) years. Pre-transplant evaluation for the majority (8/12, 66.7%) did not reveal a prior history of TB or TB treatment, but 9/12 were from TB intermediate or high-burden countries. Seven patients were initially treated with the quadruple first-line anti-TB regimen. Those who had early RR confirmation (5/12) via Xpert MTB/RIF assay were initiated on alternative therapies. Final regimens were individualized based on susceptibility profiles and tolerability. Adverse events were reported in seven recipients, including acute kidney injury (n = 3), cytopenias (n = 3), and jaundice (n = 2). Four recipients died, with two deaths attributable to TB. The remaining eight patients who survived had functioning allografts at the last follow-up.. MDR-TB treatment in transplant recipients is associated with many complications. Xpert MTB/RIF detected RR early and guided early empiric therapy.

Topics: Adolescent; Adult; Female; Humans; Isoniazid; Male; Middle Aged; Rifampin; Transplant Recipients; Tuberculosis, Multidrug-Resistant; Young Adult

To develop the 'Stronger Towns Index': a deprivation index that took into account characteristics of areas encompassing towns that may be eligible for redevelopment funding and explore how this index was associated with self-rated health and migration within England between 2001 and 2011.. There were areas in the lowest deciles of Town Strength who did not receive funding. After multiple adjustment, LS members living in areas with higher deciles were significantly more likely (7% to 38%) to report good health than those in the lowest decile in 2001. Remaining in the same decile between 2001 and 2011 was associated with 7% lower odds of good self-rated health in 2011.. It is important to consider health in towns when allocating funding. Areas in the Midlands may have missed out on funding which might help mitigate poor health.. Ferritin levels <30µg/L were associated with unexplained infertility and might be screened in the future. Further studies with a focus on iron deficiency and iron treatment on women with unexplained infertility are warranted.. This EGM provides a valuable resource for researchers, policy-makers and the public to access the available evidence on the determinants of various COVID-19 health-related behaviours. The map can also be used to help guide research commissioning, by evidence synthesis teams and evidence intermediaries to inform policy during the ongoing pandemic and potential future outbreaks of COVID-19 or other respiratory infections. Evidence included in the map will be explored further through a series of systematic reviews examining the strength of the associations between malleable determinants and the uptake and maintenance of individual protective behaviours.. Patients with polymicrobial bloodstream infections are typically critically ill and harbor multidrug-resistant bacteria. Thus, to minimize mortality rate in critically ill patients, changes in infectious flora should be monitored, antibiotics selected reasonably, and invasive procedures reduced.. Altogether, these findings clearly revealed the great potential of the in vitro biological activity of linseed extract as a safe source for combatting multidrug-resistant. In this work, the capture of carbon dioxide using a dense hollow fiber membrane was studied experimentally and theoretically. The factors affecting the flux and recovery of carbon dioxide were studied using a lab-scale system. Experiments were conducted using a mixture of methane and carbon dioxide to simulate natural gas. The effect of changing the CO. Persistent gender and racial disparities in high-impact medical and critical care journals underscore the need to revise policies and strategies to encourage greater diversity in critical care research.. Thirty evaluable patients were enrolled. Median age was 60.5 years. Median follow-up for all patients was 17 months. Ten patients (33%) experienced grade ≥ 3 treatment-related adverse events, the most common being neutropenia and diarrhea; 50% required ≥ 1 dose reduction. The disease control rate was 90% (progressive disease: 10%, partial response: 23%, stable disease: 67%). There was zero treatment-related mortality. Twenty-two patients (73%, 90% CI 57-86; p = 0.008) completed all chemotherapy and surgery. Two patients (9%) who successfully underwent resection had minor postoperative complications. Median length of hospital stay was 4 days. Median RFS was 7.1 months. Median OS for the entire cohort was 24 months and was not reached in patients who underwent surgical resection.. Neoadjuvant treatment with gemcitabine, cisplatin, and nab-paclitaxel is feasible and safe prior to resection of intrahepatic cholangiocarcinoma and does not adversely impact perioperative outcomes.

Topics: Acetogenins; Acute Disease; Acute Kidney Injury; Administration, Intravenous; Aged; Albumins; Alcoholism; Aldehyde Dehydrogenase; Aldehyde Dehydrogenase, Mitochondrial; alpha-Glucosidases; Anemia; Animals; Anthozoa; Anti-Bacterial Agents; Anti-Infective Agents; Antibodies, Bacterial; Antigens, Bacterial; Antihypertensive Agents; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Antioxidants; Apoptosis; Ascites; Asthma; Bacteria; beta-Lactamases; Bile Duct Neoplasms; Bile Ducts, Intrahepatic; Binding Sites; Biological Availability; Biomass; Borderline Personality Disorder; Brain; Brucella abortus; Brucella melitensis; Brucellosis; Calcium; Carbapenems; Case-Control Studies; Caseins; Cattle; CD8-Positive T-Lymphocytes; Ceftaroline; Cell Line; Cell Line, Tumor; Cell Physiological Phenomena; Cell Proliferation; Cephalosporins; Chemotherapy, Adjuvant; China; Chitin; Chlorella; Chlorophyll; Chlorophyll A; Chlorophyta; Cholangiocarcinoma; Cisplatin; Conotoxins; Contrast Media; Conus Snail; Cross-Sectional Studies; Cytokines; Decapodiformes; Deoxycytidine; Diagnostic and Statistical Manual of Mental Disorders; Dietary Fiber; Diterpenes; DNA Methylation; Dogs; Double-Blind Method; Drug Design; Drug Resistance, Bacterial; Drug Resistance, Multiple, Bacterial; Drug Screening Assays, Antitumor; Eicosapentaenoic Acid; Enzyme-Linked Immunosorbent Assay; Epidermis; Escherichia coli; Escherichia coli Infections; Extraintestinal Pathogenic Escherichia coli; Fatty Acids; Fatty Acids, Unsaturated; Fatty Acids, Volatile; Feasibility Studies; Feces; Female; Ferritins; Fluorodeoxyglucose F18; Gastrectomy; Gastrointestinal Microbiome; Gemcitabine; Glomerular Filtration Rate; Glucose; Glycerol; Granulocyte-Macrophage Colony-Stimulating Factor; HeLa Cells; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; Hypoxia-Inducible Factor-Proline Dioxygenases; Immunoassay; Immunoglobulin G; India; Infant, Newborn; Infertility; Inflammation; Intensive Care Units; Iron; Iron Deficiencies; Kidney; Lacticaseibacillus rhamnosus; Laurencia; Leukocytes; Lipids; Liver Cirrhosis; Long Interspersed Nucleotide Elements; Longitudinal Studies; Male; Mesenchymal Stem Cells; Methicillin-Resistant Staphylococcus aureus; Mice; Microalgae; Microbial Sensitivity Tests; Microscopy; Middle Aged; Minerals; Molecular Conformation; Molecular Docking Simulation; Molecular Structure; Mycobacterium tuberculosis; Myeloid Cells; Myeloid-Derived Suppressor Cells; Neoadjuvant Therapy; Neoplasm Recurrence, Local; Nephropidae; Nicotinic Antagonists; Nitrogen; Obesity; Oxaliplatin; Paclitaxel; Panax; Pancreatic Neoplasms; Pancreatitis; Personality; Personality Disorders; Personality Inventory; Photobioreactors; Plant Extracts; Plasmalogens; Plasmids; Polymorphism, Genetic; Polynesia; Positron Emission Tomography Computed Tomography; Positron-Emission Tomography; Prebiotics; Predictive Value of Tests; Prognosis; Prolyl-Hydroxylase Inhibitors; Rabbits; Radiopharmaceuticals; Rats; Rats, Wistar; Receptors, Nicotinic; Recombinant Proteins; Retrospective Studies; Rifampin; Risk Factors; RNA, Ribosomal, 16S; Salinity; Seaweed; Sensitivity and Specificity; Sepsis; Sesquiterpenes; Severity of Illness Index; Shock, Septic; Silicones; Single Photon Emission Computed Tomography Computed Tomography; Skin; Snails; Solubility; Solvents; Sputum; Staphylococcal Infections; Stomach Neoplasms; Stramenopiles; Structure-Activity Relationship; Technetium Tc 99m Exametazime; Technology; Terpenes; Tuberculosis; Tuberculosis, Multidrug-Resistant; Urinary Catheters; Urinary Tract Infections; Vascular Endothelial Growth Factor A; Virulence Factors; Water; Wound Healing

Tuberculosis (TB) is the leading cause of death due to an infectious agent, with more than 1.5 million deaths attributed to TB annually worldwide. The global dissemination of drug resistance across Mycobacterium tuberculosis (Mtb) strains, causative of TB, resulted in an estimated 450 000 cases of drug-resistant (DR) TB in 2021. Dysregulated immune responses have been observed in patients with multidrug resistant (MDR) TB, but the effects of drug resistance acquisition and impact on host immunity remain obscure. In this review, we compile studies that span aspects of altered host-pathogen interactions and highlight research that explores how drug resistance and immunity might intersect. Understanding the immune processes differentially induced during DR TB would aid the development of rational therapeutics and vaccines for patients with MDR TB.

Topics: Antitubercular Agents; Humans; Mycobacterium tuberculosis; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Studying treatment duration for rifampicin-resistant and multidrug-resistant tuberculosis (MDR/RR-TB) using observational data is methodologically challenging. We aim to present a hypothesis generating approach to identify factors associated with shorter duration of treatment.. We conducted an individual patient data meta-analysis among MDR/RR-TB patients restricted to only those with successful treatment outcomes. Using multivariable linear regression, we estimated associations and their 95% confidence intervals (CI) between the outcome of individual deviation in treatment duration (in months) from the mean duration of their treatment site and patient characteristics, drug resistance, and treatments used.. Overall, 6702 patients with successful treatment outcomes from 84 treatment sites were included. We found that factors commonly associated with poor treatment outcomes were also associated with longer treatment durations, relative to the site mean duration. Use of bedaquiline was associated with a 0.51 (95% CI: 0.15, 0.87) month decrease in duration of treatment, which was consistent across subgroups, while MDR/RR-TB with fluoroquinolone resistance was associated with 0.78 (95% CI: 0.36, 1.21) months increase.. We describe a method to assess associations between clinical factors and treatment duration in observational studies of MDR/RR-TB patients, that may help identify patients who can benefit from shorter treatment.

Topics: Antitubercular Agents; Duration of Therapy; Fluoroquinolones; Humans; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant

Multidrug-resistant (MDR) tuberculosis (TB), resistant to isoniazid and rifampicin, continues to be one of the most important threats to controlling the TB epidemic. Over the last few years, there have been promising pharmacological advances in the paradigm of MDR TB treatment: new and repurposed drugs have shown excellent bactericidal and sterilizing activity against

Topics: Antitubercular Agents; Humans; Isoniazid; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Early diagnosis, including universal drug-susceptibility testing for all patients with tuberculosis, remains a key priority for tuberculosis elimination by 2035. The drug-resistant tuberculosis care cascade remains persistently challenged by substantial gaps in timely diagnosis and treatment of drug-resistant tuberculosis. Current diagnostics for drug-resistant tuberculosis are limited with respect to accuracy, time to results, affordability, suitability for resource-poor endemic settings, and accessibility for use at the point of care. WHO endorsement of the novel Xpert MTB/XDR assay holds notable promise for expanding access to testing and rapid diagnosis of tuberculosis drug resistance. The Xpert MTB/XDR assay detects resistance to isoniazid, ethionamide, fluoroquinolones, and second-line injectables, and is indicated for testing in patients with confirmed pulmonary tuberculosis. However, this iteration of the Xpert MTB/XDR cartridge might have less of an effect than expected, as WHO has since downgraded the role of second-line injectable agents in treating drug-resistant tuberculosis, and has revised case definitions of drug-resistant tuberculosis to incorporate resistance to new drugs. This Personal View explores the strengths and limitations of the Xpert MTB/XDR assay in the detection of drug resistance, the assay's ability to inform appropriate drug-resistant tuberculosis drug selection, and the optimal placement of the Xpert XDR assay in the laboratory diagnostic workflow.

Topics: Drug Resistance, Bacterial; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis; Tuberculosis, Multidrug-Resistant

Tuberculosis is second only to COVID-19 as a cause of death from a single infectious agent. In 2020, almost 10 million people were estimated to have developed tuberculosis and it caused 1·5 million deaths. Around a quarter of deaths caused by antimicrobial resistance are due to rifampicin-resistant tuberculosis. Antimicrobial resistance surveillance systems for many bacterial pathogens are still in the early stages of implementation in many countries, and do not yet allow for the estimation of disease burden at the national level. In this Personal View, we present the achievements, challenges, and way forward for the oldest and largest global antimicrobial resistance surveillance system. Hosted by WHO since 1994, the Global Project on Anti-Tuberculosis Drug Resistance Surveillance has served as a platform for the evaluation of the trends in anti-tuberculosis drug resistance for over 25 years at country, regional, and global levels. With an estimated 465 000 incident cases of multidrug-resistant and rifampicin-resistant tuberculosis in 2019, drug-resistant tuberculosis remains a public health crisis. The COVID-19 pandemic has reversed years of progress in providing essential tuberculosis services and reducing disease burden. The number of people diagnosed with drug-resistant tuberculosis has dropped by 22% since before the pandemic, and the number of patients provided with treatment for drug-resistant tuberculosis has dropped by 15%. Now more than ever, closing gaps in the detection of drug-resistant tuberculosis requires investment in research and development of new diagnostic tools and their rollout, expansion of sample transport systems, and the implementation of data connectivity solutions.

Topics: Antitubercular Agents; COVID-19; Humans; Mycobacterium tuberculosis; Pandemics; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

The aim of this review is to inform the reader on the latest developments in epidemiology, diagnostics and management.. Drug-resistant Tuberculosis (DR-TB) continues to be a current global health threat, and is defined by higher morbidity and mortality, sequelae, higher cost and complexity. The WHO classifies drug-resistant TB into 5 categories: isoniazid-resistant TB, rifampicin resistant (RR)-TB and MDR-TB, (TB resistant to isoniazid and rifampicin), pre-extensively drug-resistant TB (pre-XDR-TB) which is MDR-TB with resistance to a fluoroquinolone and finally XDR-TB that is TB resistant to rifampicin, plus any fluoroquinolone, plus at least one further priority A drug (bedaquiline or linezolid). Of 500,000 estimated new cases of RR-TB in 2020, only 157 903 cases are notified. Only about a third of cases are detected and treated annually.. Recently newer rapid diagnostic methods like the GeneXpert, whole genome sequencing and Myc-TB offer solutions for rapid detection of resistance.. The availability of new TB drugs and shorter treatment regimens have been recommended for the management of DR-TB.. Despite advances in diagnostics and treatments we still have to find and treat two thirds of the drug resistant cases that go undetected and therefore go untreated each year. Control of TB and elimination will only occur if cases are detected, diagnosed and treated promptly.

Topics: Antitubercular Agents; Extensively Drug-Resistant Tuberculosis; Humans; Isoniazid; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Programmes that introduce rapid molecular tests for tuberculosis and tuberculosis drug resistance aim to bring tests closer to the community, and thereby cut delay in diagnosis, ensure early treatment, and improve health outcomes, as well as overcome problems with poor laboratory infrastructure and inadequately trained personnel. Yet, diagnostic technologies only have an impact if they are put to use in a correct and timely manner. Views of the intended beneficiaries are important in uptake of diagnostics, and their effective use also depends on those implementing testing programmes, including providers, laboratory professionals, and staff in health ministries. Otherwise, there is a risk these technologies will not fit their intended use and setting, cannot be made to work and scale up, and are not used by, or not accessible to, those in need.. To synthesize end-user and professional user perspectives and experiences with low-complexity nucleic acid amplification tests (NAATs) for detection of tuberculosis and tuberculosis drug resistance; and to identify implications for effective implementation and health equity.. We searched MEDLINE, Embase, CINAHL, PsycInfo and Science Citation Index Expanded databases for eligible studies from 1 January 2007 up to 20 October 2021. We limited all searches to 2007 onward because the development of Xpert MTB/RIF, the first rapid molecular test in this review, was completed in 2009.. We included studies that used qualitative methods for data collection and analysis, and were focused on perspectives and experiences of users and potential users of low-complexity NAATs to diagnose tuberculosis and drug-resistant tuberculosis. NAATs included Xpert MTB/RIF, Xpert MTB/RIF Ultra, Xpert MTB/XDR, and the Truenat assays. Users were people with presumptive or confirmed tuberculosis and drug-resistant tuberculosis (including multidrug-resistant (MDR-TB)) and their caregivers, healthcare providers, laboratory technicians and managers, and programme officers and staff; and were from any type of health facility and setting globally. MDR-TB is tuberculosis caused by resistance to at least rifampicin and isoniazid, the two most effective first-line drugs used to treat tuberculosis.. We used a thematic analysis approach for data extraction and synthesis, and assessed confidence in the findings using GRADE CERQual approach. We developed a conceptual framework to illustrate how the findings relate.. We found 32 studies. All studies were conducted in low- and middle-income countries. Twenty-seven studies were conducted in high-tuberculosis burden countries and 21 studies in high-MDR-TB burden countries. Only one study was from an Eastern European country. While the studies covered a diverse use of low-complexity NAATs, in only a minority of studies was it used as the initial diagnostic test for all people with presumptive tuberculosis. We identified 18 review findings and grouped them into three overarching categories. Critical aspects users value People with tuberculosis valued reaching diagnostic closure with an accurate diagnosis, avoiding diagnostic delays, and keeping diagnostic-associated cost low. Similarly, healthcare providers valued aspects of accuracy and the resulting confidence in low-complexity NAAT results, rapid turnaround times, and keeping cost to people seeking a diagnosis low. In addition, providers valued diversity of sample types (for example, gastric aspirate specimens and stool in children) and drug resistance information. Laboratory professionals appreciated the improved ease of use, ergonomics, and biosafety of low-complexity NAATs compared to sputum microscopy, and increased staff satisfaction. Challenges reported to realizing those values People with tuberculosis and healthcare workers were reluctant to test for tuberculosis (including MDR-TB) due to fears, stigma, or cost concerns. Thus, low-complexity NAAT testing is not implemented with sufficient support or discretion to overcome barriers that are common to other approaches to testing for tuberculosis. Delays were reported at many steps of the diagnostic pathway owing to poor sample quality; difficulties with transporting specimens; lack of sufficient resources; maintenance of low-complexity NAATs; increased workload; inefficient work and patient flows; over-reliance on low-complexity NAAT results in lieu of clinical judgement; and lack of data-driven and inclusive implementation processes. These challenges were reported to lead to underutilization.  Concerns for access and equity The reported concerns included sustainable funding and maintenance and equitable use of resources to access low-complexity NAATs, as well as conflicts of interest between donors and people implementing the tests. Also, lengthy diagnostic delays, underutilization of low-complexity NAATs, lack of tuberculosis diagnostic facilities in the community, and too many eligibility restrictions hampered. Low-complexity diagnostics have been presented as a solution to overcome deficiencies in laboratory infrastructure and lack of skilled professionals. This review indicates this is misleading. The lack of infrastructure and human resources undermine the added value new diagnostics of low complexity have for recipients and providers. We had high confidence in the evidence contributing to these review findings. Implementation of new diagnostic technologies, like those considered in this review, will need to tackle the challenges identified in this review including weak infrastructure and systems, and insufficient data on ground level realities prior and during implementation, as well as problems of conflicts of interest in order to ensure equitable use of resources.

Topics: Child; Drug Resistance; Humans; Nucleic Acid Amplification Techniques; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

The impact of low body mass index (BMI) at initiation of rifampicin-resistant tuberculosis (RR-TB) treatment on outcomes is uncertain. We evaluated the association between BMI at RR-TB treatment initiation and end-of-treatment outcomes.. We performed an individual participant data meta-analysis of adults aged ≥18 years with RR-TB whose BMI was documented at treatment initiation. We compared odds of any unfavorable treatment outcome, mortality, or failure/recurrence between patients who were underweight (BMI <18.5 kg/m2) and not underweight. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were estimated using logistic regression, with matching on demographic, clinical, and treatment-related factors. We evaluated effect modification by human immunodeficiency virus (HIV) status and other variables using likelihood ratio tests. We also estimated cumulative incidence of mortality during treatment stratified by HIV.. Overall, 5148 patients were included; 1702 (33%) were underweight at treatment initiation. The median (interquartile range) age was 37 years (29 to 47), and 455 (9%) had HIV. Compared with nonunderweight patients, the aOR among underweight patients was 1.7 (95% CI, 1.4-1.9) for any unfavorable outcome, 3.1 (2.4-3.9) for death, and 1.6 (1.2-2.0) for failure/recurrence. Significant effect modification was found for World Health Organization region of treatment. Among HIV-negative patients, 24-month mortality was 14.8% (95% CI, 12.7%-17.3%) for underweight and 5.6% (4.5%-7.0%) for not underweight patients. Among patients with HIV, corresponding values were 33.0% (25.6%-42.6%) and 20.9% (14.1%-27.6%).. Low BMI at treatment initiation for RR-TB is associated with increased odds of unfavorable treatment outcome, particularly mortality.

Topics: Adolescent; Adult; Antitubercular Agents; Body Mass Index; HIV Infections; Humans; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Weight Loss

To evaluate the value of matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) in the detection of drug resistance of Mycobacterium tuberculosis in re-treated patients.. MALDI-TOF MS was used to detect the resistance of 202 cases of retreatment pulmonary tuberculosis infection strains to isoniazid (INH), rifampin (RFP), ethambutol (EMB), streptomycin (SM), ofloxacin (Ofx), moxifloxacin (Mfx), amikacin (Am), Kanamycin (Km) and capreomycin (Cm), and the results were compared with those of BACTEC 960 liquid culture detection to compare the coincidence rate of the two methods.. MALDI-TOF MS detected 60 copies of Mtb gene mutation, and drug-resistant gene mutation strains accounted for 34.68% (60/173) of positive strains. Rifampicin-related rpoB gene mutations accounted for 86.67% (52/60), isoniazid-related katG + inhA gene mutations accounted for 80.00% (48/60) and inhA-15 gene mutations accounted for 8.33% (5/60), streptomycin-related rpsL gene mutations accounted for 28.33% (17/60), ethambutol-related embB gene mutations accounted for 45.00% (27/60), quinolone-related gyrA basic mutation accounted for 26.67% (16/60), ethyl/propylthiamine-related embB gene mutation accounted for 36.67% (22/60) and inhA-15 gene mutation accounted for 10.00% (6/60), aminoglycoside-related rrs gene mutation accounted for 26.67% (16/60), clofazimine Fazimine, bedaquiline related Rv0678 193 gene mutations accounted for 3.33% (2/60), pyrazinamide, p-aminosalicylate, linezolid were not seen mutated genes. Multi-gene mutant strains accounted for 63.33% (38/60) of drug-resistant strains.. MALDI-TOF MS assay has good agreement with BACTEC960 liquid culture drug sensitivity test, which can be a rapid and effective method to screen for drug resistance of Mycobacterium tuberculosis, and has some clinical application value in patients with relapse tuberculosis.

Topics: Antitubercular Agents; Drug Resistance; Ethambutol; Humans; Isoniazid; Lasers; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifampin; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Streptomycin; Tuberculosis, Lymph Node; Tuberculosis, Multidrug-Resistant

The World Health Organization (WHO) End TB Strategy stresses universal access to drug susceptibility testing (DST). DST determines whether Mycobacterium tuberculosis bacteria are susceptible or resistant to drugs. Xpert MTB/XDR is a rapid nucleic acid amplification test for detection of tuberculosis and drug resistance in one test suitable for use in peripheral and intermediate level laboratories. In specimens where tuberculosis is detected by Xpert MTB/XDR, Xpert MTB/XDR can also detect resistance to isoniazid, fluoroquinolones, ethionamide, and amikacin.. To assess the diagnostic accuracy of Xpert MTB/XDR for pulmonary tuberculosis in people with presumptive pulmonary tuberculosis (having signs and symptoms suggestive of tuberculosis, including cough, fever, weight loss, night sweats). To assess the diagnostic accuracy of Xpert MTB/XDR for resistance to isoniazid, fluoroquinolones, ethionamide, and amikacin in people with tuberculosis detected by Xpert MTB/XDR, irrespective of rifampicin resistance (whether or not rifampicin resistance status was known) and with known rifampicin resistance.. We searched multiple databases to 23 September 2021. We limited searches to 2015 onwards as Xpert MTB/XDR was launched in 2020.. Diagnostic accuracy studies using sputum in adults with presumptive or confirmed pulmonary tuberculosis. Reference standards were culture (pulmonary tuberculosis detection); phenotypic DST (pDST), genotypic DST (gDST),composite (pDST and gDST) (drug resistance detection).. Two review authors independently reviewed reports for eligibility and extracted data using a standardized form. For multicentre studies, we anticipated variability in the type and frequency of mutations associated with resistance to a given drug at the different centres and considered each centre as an independent study cohort for quality assessment and analysis. We assessed methodological quality with QUADAS-2, judging risk of bias separately for each target condition and reference standard. For pulmonary tuberculosis detection, owing to heterogeneity in participant characteristics and observed specificity estimates, we reported a range of sensitivity and specificity estimates and did not perform a meta-analysis. For drug resistance detection, we performed meta-analyses by reference standard using bivariate random-effects models. Using GRADE, we assessed certainty of evidence of Xpert MTB/XDR accuracy for detection of resistance to isoniazid and fluoroquinolones in people irrespective of rifampicin resistance and to ethionamide and amikacin in people with known rifampicin resistance, reflecting real-world situations. We used pDST, except for ethionamide resistance where we considered gDST a better reference standard.. We included two multicentre studies from high multidrug-resistant/rifampicin-resistant tuberculosis burden countries, reporting on six independent study cohorts, involving 1228 participants for pulmonary tuberculosis detection and 1141 participants for drug resistance detection. The proportion of participants with rifampicin resistance in the two studies was 47.9% and 80.9%. For tuberculosis detection, we judged high risk of bias for patient selection owing to selective recruitment. For ethionamide resistance detection, we judged high risk of bias for the reference standard, both pDST and gDST, though we considered gDST a better reference standard. Pulmonary tuberculosis detection - Xpert MTB/XDR sensitivity range, 98.3% (96.1 to 99.5) to 98.9% (96.2 to 99.9) and specificity range, 22.5% (14.3 to 32.6) to 100.0% (86.3 to 100.0); median prevalence of pulmonary tuberculosis 91.3%, (interquartile range, 89.3% to 91.8%), (2 studies; 1 study reported on 2 cohorts, 1228 participants; very low-certainty evidence, sensitivity and specificity). Drug resistance detection People irrespective of rifampicin resistance - Isoniazid resistance: Xpert MTB/XDR summary sensitivity and specificity (95% confidence interval (CI)) were 94.2% (87.5 to 97.4) and 98.5% (92.6 to 99.7) against pDST, (6 cohorts, 1083 participants, moderate-certainty evidence, sensitivity and specificity). - Fluoroquinolone resistance: Xpert MTB/XDR summary sensitivity and specificity were 93.2% (88.1 to 96.2) and 98.0% (90.8 to 99.6) against pDST, (6 cohorts, 1021 participants; high-certainty evidence, sensitivity; moderate-certainty evidence, specificity). People with known rifampicin resistance - Ethionamide resistance: Xpert MTB/XDR summary sensitivity and specificity were 98.0% (74.2 to 99.9) and 99.7% (83.5 to 100.0) against gDST, (4 cohorts, 434 participants; very low-certainty evidence, sensitivity and specificity). - Amikacin resistance: Xpert MTB/XDR summary sensitivity and specificity were 86.1% (75.0 to 92.7) and 98.9% (93.0 to 99.8) against pDST, (4 cohorts, 490 participants; low-certainty evidence, sensitivity; high-certainty evidence, specificity). Of 1000 people with pulmonary tuberculosis, detected as tuberculosis by Xpert MTB/XDR: - where 50 have isoniazid resistance, 61 would have an Xpert MTB/XDR result indicating isoniazid resistance: of these, 14/61 (23%) would not have isoniazid resistance (FP); 939 (of 1000 people) would have a result indicating the absence of isoniazid resista. Review findings suggest that, in people determined by Xpert MTB/XDR to be tuberculosis-positive, Xpert MTB/XDR provides accurate results for detection of isoniazid and fluoroquinolone resistance and can assist with selection of an optimised treatment regimen. Given that Xpert MTB/XDR targets a limited number of resistance variants in specific genes, the test may perform differently in different settings. Findings in this review should be interpreted with caution. Sensitivity for detection of ethionamide resistance was based only on Xpert MTB/XDR detection of mutations in the inhA promoter region, a known limitation. High risk of bias limits our confidence in Xpert MTB/XDR accuracy for pulmonary tuberculosis. Xpert MTB/XDR's impact will depend on its ability to detect tuberculosis (required for DST), prevalence of resistance to a given drug, health care infrastructure, and access to other tests.

Topics: Adult; Amikacin; Antibiotics, Antitubercular; Drug Resistance, Bacterial; Ethionamide; Fluoroquinolones; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis, Lymph Node; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Line probe assays (LPAs) are PCR-based assays used for the rapid diagnosis of Mycobacterium tuberculosis (MTB) and drug-resistant tuberculosis (DR-TB). But studies on its performance are insufficient. Thus, in this study, we conducted a systematic review and meta-analysis to evaluate the effect of LPAs in the detection of MTB and drug-resistant TB in comparison with the traditional culture and DST methods.. A systemic literature search was conducted on the Web of Science, Embase, PubMed, the Cochrane Library, Scopus, and OVID databases. All the included studies were classified according to different detecting objects. Sensitivity, specificity, Positive Likely Ratio (PLR), Negative Likely Ratio (NLR), Diagnostic Odds Ratio (DOR), corresponding 95% confidence interval, Area Under Curve (AUC), Deeks' funnel plot, and Bivariate Boxplot was used to do the evaluation.. 147 studies included 491 datasets, with 182,448 samples, were incorporated into our analysis. The sensitivity (95% CI), specificity (95% CI), PLR, NLR, DOR and AUC for MTB were 0.89 (0.86 to 0.92), 0.94 (0.90 to 0.97), 15.70, 0.11, 139 and 0.96, respectively; for rifampicin-resistant TB were 0.96 (0.95 to 0.97), 0.99 (0.98 to 0.99), 82.9, 0.04, 1994 and 1.00, respectively; for isoniazid-resistant TB were 0.91 (0.89 to 0.93), 0.99 (0.98 to 0.99), 83.4, 0.09, (0.99 to 1.00), 195.7, 0.07, 2783 and 1.00, respectively; for Multi-drug resistant TB (MDR-TB) were 0.93 (0.90 to 0.95), 1.00 (0.99 to 1.00), 195.7, 0.07, 2783 and 1.00, respectively; for extensively drug-resistant TB (XDR-TB) were 0.60 (0.33 to 0.82), 1.00 (0.95 to 1.00), 291.3, 0.4, 726 and 0.95, respectively; for (second-line drug-resistant TB) SLID-TB were 0.83 (0.78 to 0.87), 0.98 (0.97 to 0.99), 44.6, 0.17, 262 and 0.98, respectively. Sensitivity in pre-extensively drug-resistant TB (Pre-XDR-TB) was 0.67, specificity was 0.91. No publication bias existed according to Deeks' funnel plot.. High diagnosis performance was confirmed in LPAs for the diagnosis of MTB and drug-resistant TB. LPAs might be a good alternative to culture and DST in detecting MTB, RR-TB, INH-TB, XDR-TB, SLID-TB, and MDR-TB. While more studies were still needed to explore the diagnosis performance of LPAs for Pre-XDR TB.

Topics: Antitubercular Agents; Extensively Drug-Resistant Tuberculosis; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

No previous systematic reviews have comprehensively investigated the features of Xpert MTB/XDR and other rapid tests to diagnose pre-XDR/XDR-TB. The aim of this systematic review is to assess existing rapid diagnostics for pre-XDR/XDR-TB from a point-of-care perspective and describe their technical characteristics (i.e., sensitivity, specificity, positive and negative predictive values).. Embase, PubMed, Scopus, and Web of Science were searched to detect the articles focused on the accuracy of commercially available rapid molecular diagnostic tests for XDR-TB according to PRISMA guidelines. The analysis compared the diagnostic techniques and approaches in terms of sensitivity, specificity, laboratory complexity, time to confirmed diagnosis.. Of 1298 records identified, after valuating article titles and abstracts, 97 (7.5%) records underwent full-text evaluation and 38 records met the inclusion criteria. Two rapid World Health Organization (WHO)-endorsed tests are available: Xpert MTB/XDR and GenoType MTBDRsl (VER1.0 and VER 2.0). Both tests had similar performance, slightly favouring Xpert, although only 2 studies were available (sensitivity 91.4-94; specificity 98.5-99; accuracy 97.2-97.7; PPV 88.9-99.1; NPV 95.8-98.9).. Xpert MTB/XDR could be suggested at near-point-of-care settings to be used primarily as a follow-on test for laboratory-confirmed TB, complementing existing rapid tests detecting at least rifampicin-resistance. Both Xpert MTB/XDR and GenoType MTBDRsl are presently diagnosing what WHO defined, in 2021, as pre-XDR-TB.

Topics: Extensively Drug-Resistant Tuberculosis; Genotype; Humans; Mycobacterium tuberculosis; Predictive Value of Tests; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

We aimed to investigate published data on treatment outcomes of multidrug-resistant (MDR)/rifampicin-resistant tuberculosis (TB) in Central and West Africa because these, to the best of our knowledge, are sparsely available.. Systematic review and meta-analysis.. The use of shorter treatment regimens and the standardized treatment conditions, including directly observed therapy in these studies, could have contributed to a high treatment success. Yet, the available literature was not fully representative of the regions, possibly highlighting the sparse resources in many of these countries. The review was registered at PROSPERO (https://www.crd.york.ac.uk/prospero/) (CRD42022353163).

Topics: Antitubercular Agents; Directly Observed Therapy; Humans; Mycobacterium tuberculosis; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant

Countries with high TB burden have expanded access to molecular diagnostic tests. However, their impact on reducing delays in TB diagnosis and treatment has not been assessed. Our primary aim was to summarize the quantitative evidence on the impact of nucleic acid amplification tests (NAAT) on diagnostic and treatment delays compared to that of the standard of care for drug-sensitive and drug-resistant tuberculosis (DS-TB and DR-TB).. We searched MEDLINE, EMBASE, Web of Science, and the Global Health databases (from their inception to October 12, 2020) and extracted time delay data for each test. We then analysed the diagnostic and treatment initiation delay separately for DS-TB and DR-TB by comparing smear vs Xpert for DS-TB and culture drug sensitivity testing (DST) vs line probe assay (LPA) for DR-TB. We conducted random effects meta-analyses of differences of the medians to quantify the difference in diagnostic and treatment initiation delay, and we investigated heterogeneity in effect estimates based on the period the test was used in, empiric treatment rate, HIV prevalence, healthcare level, and study design. We also evaluated methodological differences in assessing time delays.. A total of 45 studies were included in this review (DS = 26; DR = 20). We found considerable heterogeneity in the definition and reporting of time delays across the studies. For DS-TB, the use of Xpert reduced diagnostic delay by 1.79 days (95% CI - 0.27 to 3.85) and treatment initiation delay by 2.55 days (95% CI 0.54-4.56) in comparison to sputum microscopy. For DR-TB, use of LPAs reduced diagnostic delay by 40.09 days (95% CI 26.82-53.37) and treatment initiation delay by 45.32 days (95% CI 30.27-60.37) in comparison to any culture DST methods.. Our findings indicate that the use of World Health Organization recommended diagnostics for TB reduced delays in diagnosing and initiating TB treatment. Future studies evaluating performance and impact of diagnostics should consider reporting time delay estimates based on the standardized reporting framework.

Topics: Delayed Diagnosis; Humans; Mycobacterium tuberculosis; Pathology, Molecular; Rifampin; Sensitivity and Specificity; Time-to-Treatment; Tuberculosis; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Outcomes of treatment of tuberculosis patients with regimens including pretomanid have not yet been systematically reviewed.. To appraise existing evidence on efficacy and safety of pretomanid in tuberculosis.. Pubmed, clinicaltrials.gov. and Cochrane library.. Quantitative studies presenting original data on clinical efficacy or safety of pretomanid.. Patients with tuberculosis.. Treatment with pretomanid or pretomanid-containing regimens in minimum one study group.. Two authors independently extracted data and assessed risk of bias. Data on efficacy (early bactericidal activity, bactericidal activity, end-of-treatment outcomes and acquired resistance) and safety were summarized in tables. Mean differences in efficacy outcomes between regimens across studies were calculated.. Eight studies were included; four randomized controlled trials on 2-week early bactericidal activity in rifampicin-susceptible tuberculosis, three trials with randomized rifampicin-susceptible tuberculosis arms and a single rifampicin-resistant tuberculosis arm (two on 8-week bactericidal activity, one on end-of-treatment outcomes), one single-arm trial with end-of-treatment outcomes in highly resistant tuberculosis. Activity of pretomanid-moxifloxacin-pyrazinamide was superior to standard treatment on daily change in colony-forming units at days 0-2, 0-56 and 7-56 and time to culture conversion in rifampicin-susceptible tuberculosis (hazard ratio: 1.7; 95% CI 1.1-2.7), but not at end of treatment in one study. This study was stopped due to serious hepatotoxic adverse events, including three deaths, in 4% (95% CI 2-8) patients on pretomanid-moxifloxacin-pyrazinamide and none in controls. In patients with uncomplicated rifampicin-resistant tuberculosis on pretomanid-moxifloxacin-pyrazinamide treatment, 91% (95% CI 59-100) had favourable end-of-treatment outcomes. In patients with highly resistant tuberculosis, 90% (95% CI 83-95) on pretomanid-bedaquiline-linezolid had favourable outcomes six months after treatment, but linezolid-related toxicity was frequent. No acquired resistance to pretomanid was reported.. Evidence suggests an important role for pretomanid in rifampicin-resistant and highly resistant tuberculosis. Trials comparing pretomanid to existing core and companion drugs are needed to further define that role.

Topics: Antitubercular Agents; Humans; Linezolid; Moxifloxacin; Nitroimidazoles; Pyrazinamide; Randomized Controlled Trials as Topic; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Tuberculosis (TB) caused by Mycobacterium tuberculosis (M. tb) still remains the deadliest infectious disease worldwide with 1.5 million deaths in 2018, of which about 15% are attributed to resistant strains. Another significant example is Mycobacterium abscessus (M. abscessus), a nontuberculous mycobacteria (NTM) responsible for cutaneous and pulmonary infections, representing up to 95% of NTM infections in cystic fibrosis (CF) patients. M. abscessus is a new clinically relevant pathogen and is considered one of the most drug-resistant mycobacteria for which standardized chemotherapeutic regimens are still lacking. Together the emergence of M. tb and M. abscessus multi-drug resistant strains with ineffective and expensive therapeutics, have paved the way to the development of new classes of anti-mycobacterial agents offering additional therapeutic options. In this context, specific inhibitors of mycobacterial lipolytic enzymes represent novel and promising antibacterial molecules to address this challenging issue. The results highlighted here include a complete overview of the antibacterial activities, either in broth medium or inside infected macrophages, of two families of promising and potent anti-mycobacterial multi-target agents, i.e. oxadiazolone-core compounds (OX) and Cyclophostin & Cyclipostins analogs (CyC); the identification and biochemical validation of their effective targets (e.g., the antigen 85 complex and TesA playing key roles in mycolic acid metabolism) together with their respective crystal structures. To our knowledge, these are the first families of compounds able to target and impair replicating as well as intracellular bacteria. We are still impelled in deciphering their mode of action and finding new potential therapeutic targets against mycobacterial-related diseases.

Topics: Antitubercular Agents; Carboxylic Ester Hydrolases; Drug Design; Enzyme Inhibitors; Humans; Lactones; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Mycolic Acids; Organophosphorus Compounds; Orlistat; Tuberculosis; Tuberculosis, Multidrug-Resistant

Tuberculosis (TB) is one of the most contagious infectious diseases worldwide. Currently, drug-resistant Mycobacterium tuberculosis (Mtb) isolates are considered as one of the main challenges in the global TB control strategy. Rapid detection of resistant strains effectively reduces morbidity and mortality of world's population. Although both culture and conventional antibiotic susceptibility testing are time-consuming, recent studies have shown that high resolution melting (HRM) assay can be used to determine the types of antibiotic resistance. In the present meta-analysis, we evaluated the discriminative power of HRM in detecting all drug-resistance cases of TB.. A systematic search was performed using databases such as Cochrane Library, Scopus, PubMed, Web of Science, and Google Scholar. Related studies on the effect of HRM in the diagnosis of drug-resistant (DR) TB cases were retrieved by April 2021. We used Meta-Disc software to evaluate the pooled diagnostic sensitivity and specificity of HRM for the detection of each type of drug-resistant cases. Finally, diagnostic value of HRM was characterized by summary receiver operating characteristic (SROC) curve and the area under the curve (AUC) method.. Overall 47 studies (4,732 Mtb isolates) met our criteria and were included in the present meta-analysis. Sensitivity, specificity, and AUC of HRM were measured for antibiotics such as isoniazid (93%, 98%, 0.987), rifampin (94%, 97%, 0963), ethambutol (82%, 87%, 0.728), streptomycin (82%, 95%, 0.957), pyrazinamide (72%, 84%, 0.845), fluoroquinolones (86%, 99%, 0.997), MDR-TB (90%, 98%, 0.989), and pan-drug-resistant TB (89%, 95%, 0.973).. The HRM assay has high accuracy for the identification of drug-resistant TB, particularly firs-line anti-TB drugs. Therefore, this method is considered as an alternative option for the rapid diagnosis of DR-TB cases. However, due to heterogeneity of included studies, the results of HRM assays should be interpreted based on conventional drug susceptibility testing.

Topics: Antitubercular Agents; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

Drug-resistant tuberculosis and extrapulmonary tuberculosis are the world major public health issues. Although some primary studies have been reported on the burden of drug-resistant tuberculosis in extrapulmonary tuberculosis patients in Ethiopia, there is no systematic review and meta-analysis that attempt to summarize the available literature. Thus, we aimed to estimates the prevalence of drug-resistance in extrapulmonary tuberculosis patients and summarize the risk factors associated with the occurrence of extrapulmonary tuberculosis in Ethiopia.. We conducted a systematic review of the published primary studies on extrapulmonary drug-resistant tuberculosis in Ethiopia.. Eight observational studies were included in this review from different regions of Ethiopia. The overall pooled prevalence of rifampicin resistance was 6% (95% CI 0.03-0.10), while isoniazid resistance was 7% (95% CI 0.03-0.12). The pooled prevalence of multidrug-resistant tuberculosis was 4% (95% CI 0.01-0.07). Previous tuberculosis treatment history and male gender are frequently reported risk factors for developing drug-resistant tuberculosis in extrapulmonary tuberculosis patients.. The current review has identified a high proportion of resistance to rifampicin, isoniazid, and multidrug-resistant tuberculosis in patients with extrapulmonary tuberculosis in Ethiopia. Clinicians should request drug susceptibility testing for all patients with presumptive extrapulmonary tuberculosis to detect drug-resistance.

Topics: Ethiopia; Humans; Isoniazid; Prevalence; Rifampin; Risk Factors; Tuberculosis, Multidrug-Resistant

Approximately 1.41 million people die annually due to tuberculosis. One of the main problems in Tuberculosis eradication is the development of resistance to various antibiotics. However, current efforts to detect resistances face challenges such as limited equipment, budget, and time. This evidence-based review investigated loop-mediated isothermal amplification, an alternative molecular diagnostic tool with promising performance and applicability in developing countries, and its use combined with Au-Nanoprobe to detect antibiotic resistance in tuberculosis. The literature search was conducted through four databases (Proquest, EBSCOhost, Scopus, and Pubmed) for useful articles on loop-mediated isothermal amplification and Au-Nanoprobe in detecting tuberculosis and tuberculosis resistance. After filtering the result with inclusion and exclusion criteria, the search produced three papers that best answer the clinical question. Loop-mediated isothermal amplification amplifies a target sequence, and Au-Nanoprobe responds to the DNA specific to the target mutant, producing an observable color change. Loop-mediated isothermal amplification and Au-Nanoprobe showed 100% sensitivity and specificity in detecting rifampicin and isoniazid resistance. Another study investigated its viability to detect tuberculosis and found 98.2% sensitivity and 88.2% specificity. Combining loop-mediated isothermal amplification and Au-Nanoprobe had a shorter time to get results and should also be relatively cheaper because it does not need a high temperature to work and requires less equipment. In conclusion, loop-mediated isothermal amplification and Au-Nanoprobe can be used as an efficient and accurate method to detect isoniazid and rifampicin-resistant tuberculosis strains. The new technology is promising for developing countries due to their high disease burden but facing several healthcare barriers.

Topics: Antibiotics, Antitubercular; DNA, Bacterial; Humans; Isoniazid; Molecular Diagnostic Techniques; Nucleic Acid Amplification Techniques; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

Xpert MTB/RIF Ultra (Xpert Ultra) and Xpert MTB/RIF are World Health Organization (WHO)-recommended rapid nucleic acid amplification tests (NAATs) widely used for simultaneous detection of Mycobacterium tuberculosis complex and rifampicin resistance in sputum. To extend our previous review on extrapulmonary tuberculosis (Kohli 2018), we performed this update to inform updated WHO policy (WHO Consolidated Guidelines (Module 3) 2020).. To estimate diagnostic accuracy of Xpert Ultra and Xpert MTB/RIF for extrapulmonary tuberculosis and rifampicin resistance in adults with presumptive extrapulmonary tuberculosis.. Cochrane Infectious Diseases Group Specialized Register, MEDLINE, Embase, Science Citation Index, Web of Science, Latin American Caribbean Health Sciences Literature, Scopus, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform, the International Standard Randomized Controlled Trial Number Registry, and ProQuest, 2 August 2019 and 28 January 2020 (Xpert Ultra studies), without language restriction.. Cross-sectional and cohort studies using non-respiratory specimens. Forms of extrapulmonary tuberculosis: tuberculous meningitis and pleural, lymph node, bone or joint, genitourinary, peritoneal, pericardial, disseminated tuberculosis. Reference standards were culture and a study-defined composite reference standard (tuberculosis detection); phenotypic drug susceptibility testing and line probe assays (rifampicin resistance detection).. Two review authors independently extracted data and assessed risk of bias and applicability using QUADAS-2. For tuberculosis detection, we performed separate analyses by specimen type and reference standard using the bivariate model to estimate pooled sensitivity and specificity with 95% credible intervals (CrIs). We applied a latent class meta-analysis model to three forms of extrapulmonary tuberculosis. We assessed certainty of evidence using GRADE.. 69 studies: 67 evaluated Xpert MTB/RIF and 11 evaluated Xpert Ultra, of which nine evaluated both tests. Most studies were conducted in China, India, South Africa, and Uganda. Overall, risk of bias was low for patient selection, index test, and flow and timing domains, and low (49%) or unclear (43%) for the reference standard domain. Applicability for the patient selection domain was unclear for most studies because we were unsure of the clinical settings. Cerebrospinal fluid Xpert Ultra (6 studies) Xpert Ultra pooled sensitivity and specificity (95% CrI) against culture were 89.4% (79.1 to 95.6) (89 participants; low-certainty evidence) and 91.2% (83.2 to 95.7) (386 participants; moderate-certainty evidence). Of 1000 people where 100 have tuberculous meningitis, 168 would be Xpert Ultra-positive: of these, 79 (47%) would not have tuberculosis (false-positives) and 832 would be Xpert Ultra-negative: of these, 11 (1%) would have tuberculosis (false-negatives). Xpert MTB/RIF (30 studies) Xpert MTB/RIF pooled sensitivity and specificity against culture were 71.1% (62.8 to 79.1) (571 participants; moderate-certainty evidence) and 96.9% (95.4 to 98.0) (2824 participants; high-certainty evidence). Of 1000 people where 100 have tuberculous meningitis, 99 would be Xpert MTB/RIF-positive: of these, 28 (28%) would not have tuberculosis; and 901 would be Xpert MTB/RIF-negative: of these, 29 (3%) would have tuberculosis. Pleural fluid Xpert Ultra (4 studies) Xpert Ultra pooled sensitivity and specificity against culture were 75.0% (58.0 to 86.4) (158 participants; very low-certainty evidence) and 87.0% (63.1 to 97.9) (240 participants; very low-certainty evidence). Of 1000 people where 100 have pleural tuberculosis, 192 would be Xpert Ultra-positive: of these, 117 (61%) would not have tuberculosis; and 808 would be Xpert Ultra-negative: of these, 25 (3%) would have tuberculosis. Xpert MTB/RIF (25 studies) Xpert MTB/RIF pooled sensitivity and specificity against culture were 49.5% (39.8 to 59.9) (644 participants; low-certainty evidence) and 98.9% (97.6 to 99.7) (2421 participants; high-certainty evidence). Of 1000 people where 100 have pleural tuberculosis, 60 would be Xpert MTB/RIF-positive: of these, 10 (17%) would not have tuberculosis; and 940 would be Xpert MTB/RIF-negative: of these, 50 (5%) would have tuberculosis. Lymph node aspirate Xpert Ultra (1 study) Xpert Ultra sensitivity and specificity (95% confidence interval) against composite reference standard we. Xpert Ultra and Xpert MTB/RIF may be helpful in diagnosing extrapulmonary tuberculosis. Sensitivity varies across different extrapulmonary specimens: while for most specimens specificity is high, the tests rarely yield a positive result for people without tuberculosis. For tuberculous meningitis, Xpert Ultra had higher sensitivity and lower specificity than Xpert MTB/RIF against culture. Xpert Ultra and Xpert MTB/RIF had similar sensitivity and specificity for rifampicin resistance. Future research should acknowledge the concern associated with culture as a reference standard in paucibacillary specimens and consider ways to address this limitation.

Topics: Adult; Antibiotics, Antitubercular; Bias; Drug Resistance, Bacterial; False Negative Reactions; False Positive Reactions; Humans; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Reagent Kits, Diagnostic; Rifampin; Sensitivity and Specificity; Tuberculosis; Tuberculosis, Lymph Node; Tuberculosis, Meningeal; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pleural

Drug-resistant tuberculosis, especially those with resistance to rifampicin (RR-TB), has become one of the main obstacles to achieving the dream of eradicating tuberculosis. Furthermore, it is necessary to combine three or four different drugs in the attempt to cure TB, however, unfortunately, there are few available that can be considered genuinely effective. Fortunately, the notable worldwide increase in RR-TB in recent years has led to the investment of resources in the development of new drugs for TB, and other drugs investigated for other diseases have been successfully tested on TB. This has resulted in a clear change in the clinical management of these patients over the last 3-4 years, and it is now easier to design therapeutic regimens and achieve higher success rates. All these changes are updated in this review.

Topics: Antitubercular Agents; Extensively Drug-Resistant Tuberculosis; Humans; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

In 2011, South Africa implemented a policy to decentralize treatment for rifampin-resistant tuberculosis (TB) to reduce durations of hospitalization and enable local treatment. We assessed policy implementation in Western Cape Province, where services expanded from 6 specialized TB hospitals to 406 facilities, by analyzing National Health Laboratory Service data on TB during 2012-2015. We calculated the percentage of patients who visited a TB hospital <1 year after rifampin-resistant TB diagnosis, the median duration of their hospitalizations, and the total distance between facilities visited. We assessed temporal changes with linear regression and stratified results by location. Of 2,878 patients, 65% were from Cape Town. In Cape Town, 29% visited a TB hospital; elsewhere, 68% visited a TB hospital. We found that hospitalizations and travel distances were shorter in Cape Town than in the surrounding areas.

Topics: Humans; Rifampin; South Africa; Tuberculosis; Tuberculosis, Multidrug-Resistant

Tuberculosis (TB) remains a leading cause of infectious death worldwide, and poverty is a major driver. Clinically, TB presents as "latent" TB and active TB disease, and the treatment for each is different. TB drugs can display "early bactericidal activity (EBA)" and / or "sterilizing activity" (clearing persisters). Isoniazid is excellent at the former, and rifampin is excellent at the latter. Pyrazinamide and ethambutol complete the first-line regimen for drug-susceptible TB, each playing a specific role. Drug-resistant TB is an increasing concern, being met, in part, with repurposed drugs (including moxifloxacin, levofloxacin, linezolid, clofazimine, and beta-lactams) and new drugs (including bedaquiline, pretomanid, and delamanid). One challenge is to select drugs without overlapping adverse drug reaction profiles. QTc interval prolongation is one such concern, but to date, it has been manageable. Drug penetration into organism sanctuaries, such as the central nervous system, bone, and pulmonary TB cavities remain important challenges. The pharmacodynamics of most TB drugs can be described by the area under the curve (AUC) divided by the minimal inhibitory concentration (MIC). The hollow fiber infection model (HFIM) and various animal models (especially mouse and macaque) allow for sophisticated pharmacokinetic/pharmacodynamic experiments. These experiments may hasten the selection of the most potent, shortest possible regimens to treat even extremely drug resistant TB. These findings can be translated to humans by optimizing drug exposure in each patient, using therapeutic drug monitoring and dose individualization.

Topics: Animals; Antitubercular Agents; Drug Monitoring; Drug Therapy, Combination; Humans; Isoniazid; Levofloxacin; Rifampin; Treatment Outcome; Tuberculosis; Tuberculosis, Multidrug-Resistant

For tuberculosis to be eradicated, the transmission of Multi-Drug-Resistant and eXtensively Drug Resistant strains of Mycobacterium tuberculosis (MDR and XDR-TB) must be considerably reduced. Drug resistant strains were initially thought to have reduced fitness, and the majority of resistant strains may actually have compromised fitness because they are found in only one or a few patients. In contrast, some MDR/XDR-TB strains are highly transmitted and cause large outbreaks. Most antibiotics target essential bacterial functions and the mutations that confer resistance to anti-TB drugs can incur fitness costs manifested as slower growth and reduced viability. The fitness costs vary with different resistance mutations and the bacilli can also accumulate secondary mutations that compensate for the compromised functions and partially or fully restore lost fitness. The compensatory mutations (CM) are different for each antibiotic, as they mitigate the deleterious effects of the specific functions compromised by the resistance mutations. CM are generally more common in strains with resistance mutations incurring the greatest fitness costs, but for RIF resistance, CM are most frequent in strains with the mutation carrying the least fitness cost, Ser450Leu. Here, we review what is known about fitness costs, CM and mechanisms of resistance to the drugs that define a strain as MDR or XDR-TB. The relative fitness costs of the resistance mutations and the mitigating effects of CM largely explain why certain mutations are frequently found in highly transmitted clusters while others are less frequently, rarely or never found in clinical isolates. The CM illustrate how drug resistance affects bacteria and how bacteria evolve to overcome the effects of the antibiotics, and thus a paradigm for how mycobacteria can evolve in response to stress.

Topics: Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Extensively Drug-Resistant Tuberculosis; Genetic Fitness; Isoniazid; Mutation; Mycobacterium tuberculosis; Rifampin; Streptomycin; Tuberculosis, Multidrug-Resistant

Globally, the incidence and mortality of tuberculosis (TB) are declining; however, low detection of drug-resistant disease threatens to reverse current progress toward global TB control. Multiple rapid molecular diagnostic tests have recently been developed to detect genetic mutations in Mycobacterium tuberculosis (Mtb) known to confer drug resistance. However, their utility depends on the frequency and distribution of resistance-associated mutations in the pathogen population. This review aimed to assess the prevalence of gene mutations associated with rifampicin (RIF)- and isoniazid (INH)-resistant Mtb in Ethiopia.. We searched the literature in PubMed/MEDLINE, Web of Science, Scopus and Cochrane Library. Data analysis was conducted in Stata 11.. Totally, 909 (95.8%) of 949 INH-resistant Mtb isolates had detectable gene mutations: 95.8% in katG315 and 5.9% in the inhA promoter region. Meta-analysis resulted in an estimated pooled prevalence of katGMUT1(S315T1) of 89.2% (95% CI 81.94-96.43%) and a pooled prevalence of inhAMUT1(C15T) of 77.5% (95% CI 57.84-97.13%). Moreover, 769 (90.8%) of 847 RIF-resistant strains had detectable rpoB gene mutations. Meta-analysis resulted in a pooled prevalence of rpoBMUT3(S531L) of 74.2% (95% CI 66.39-82.00%).. RIF-resistant Mtb were widespread, particularly those harbouring rpoB(S531L) mutation. Similarly, INH-resistant Mtb with katG(S315T1) and inhA(C15T) mutations were common. Tracking S531L, S315T1 and C15T mutations among RIF- and INH-resistant isolates, respectively, would be diagnostically and epidemiologically valuable. Rapid diagnosis of RIF- and INH-resistant Mtb would expedite modification of TB treatment regimens, and proper timely infection control interventions could reduce the risk of development and transmission of multidrug-resistant TB.

Topics: Drug Resistance; Ethiopia; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Prevalence; Rifampin; Tuberculosis, Multidrug-Resistant

No abstract available.

Topics: Antitubercular Agents; Clinical Protocols; Humans; Rifampin; Tuberculosis, Multidrug-Resistant

Traditionally children have been treated for tuberculosis (TB) based on data extrapolated from adults. However, we know that children present unique challenges that deserve special focus. New data on optimal drug selection and dosing are emerging with the inclusion of children in clinical trials and ongoing research on age-related pharmacokinetics and pharmacodynamics. We discuss the changing treatment landscape for drug-susceptible and drug-resistant paediatric tuberculosis in both the most common (intrathoracic) and most severe (central nervous system) forms of disease, and address the current knowledge gaps for improving patient outcomes.

Topics: Antitubercular Agents; Child; Drug Therapy, Combination; Duration of Therapy; Ethambutol; Humans; Isoniazid; Pyrazinamide; Rifampin; Tuberculosis; Tuberculosis, Central Nervous System; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Tuberculosis and diabetes mellitus are both important global health problems now. Previous studies have drawn different conclusions about the impact of diabetes on drug resistance in patients with newly diagnosed tuberculosis.. We conducted a systematic search in four databases: PubMed, EMBSE, Cochrane Library, and Web of Science. The relative risk (RR) was applied to assess the association of diabetes with drug resistance and the STATA version 12.0 was used for data synthesis.. A total of 13 studies involving 33,747 patients were included in our study. The pooled results revealed that presence of diabetes was significantly associated with isoniazid resistance (RR =1.22, 95% CI: 1.04-1.43) in patients with newly diagnosed tuberculosis. However, no significant impact of diabetes on rifampicin resistance (RR =0.67, 95% CI: 0.41-1.11) or multi-drug resistance (MDR) (RR =1.28, 95% CI: 0.93-1.75) was observed. The results of subgroup analysis were similar to the pooled results. No significant publication bias for the results of MDR was found.. In patients with newly diagnosed tuberculosis, diabetes is associated with isoniazid resistance. However, there is no significant impact of diabetes on the rifampicin resistance or MDR. However, these findings still need to be verified in the future.

Topics: Adult; Aged; Aged, 80 and over; Antibiotics, Antitubercular; Antitubercular Agents; Comorbidity; Diabetes Complications; Drug Resistance; Female; Humans; Isoniazid; Male; Middle Aged; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

耐多药结核病（MDR-TB）和利福平耐药结核病（RR-TB）仍然是全球严重的公共卫生问题之一。化学治疗是MDR-TB和RR-TB最重要的治疗手段，但存在治疗周期长、临床疗效差、不良反应多及病死率高等问题，因此，新药研发、优化和改进化疗方案对于提高该病的治愈率和生存率尤为重要。除了已批准上市的新药如贝达喹啉、德拉马尼、利奈唑胺、PA-824外，还有针对MTB的约10余种新化合物正处于不同的临床试验阶段。该病的化疗方案包括长程方案和短程方案，许多国家和地区均开展了不同程度的研究。本文就MDR-TB和RR-TB的化疗进展综述如下。.

Topics: Antitubercular Agents; Drug Resistance, Microbial; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Tuberculosis is caused by the M. tuberculosis complex. Its slow growth delays the bacteriological diagnosis based on phenotypic tests. Molecular biology has significantly reduced this delay, notably thanks to the deployment of the Xpert® MTB/RIF test (Cepheid), which detects the M. tuberculosis complex and rifampicin resistance in 2hours. Other tests detecting isoniazid and second-line antituberculous drugs resistance have been developed. However, the performances of molecular tests are significantly reduced if the acid-fast bacilli microscopy screening is negative. It is therefore crucial to limit their indication to strong clinical suspicions. Resistance detection tests only explore certain characterized positions; however, not all drug-resistance mutations are known. Moreover, the performances vary for different antituberculous drugs. The advent of genomic sequencing is promising. Its integration into routine workflow still needs to be evaluated and the data analysis remains to be standardized. The rise of molecular biology techniques has revolutionized the diagnosis of tuberculosis and drug resistance. However, they remain screening tests; results still have to be confirmed by phenotypic reference methods.

Topics: Antitubercular Agents; Diagnostic Tests, Routine; Drug Resistance, Multiple, Bacterial; Humans; Microbial Sensitivity Tests; Molecular Diagnostic Techniques; Mycobacterium tuberculosis; Predictive Value of Tests; Rifampin; Sensitivity and Specificity; Tuberculosis; Tuberculosis, Multidrug-Resistant

This study aimed to explore the relationship between glycosylated hemoglobin (HbA1c) and the risk of anti-tuberculosis (TB) drug resistance for TB-type 2 diabetes mellitus (T2DM) patients.. From March 2014 to June 2019, medical records from multiple centers were searched. Logistic regression analyses were performed. A predictive model for multidrug-resistance (MDR) was developed and validated. Calibration and discrimination of the model were assessed.. Inconsistent results were found in the systemic review. A multicenter chart review with 657 records was thus conducted. The HbA1c <7% group and HbA1c ≥7% group had 390 and 267 patients, respectively. The HbA1c<7% group had a lower risk of developing rifampicin resistance, isoniazid resistance and MDR, with odd ratios (ORs) of 1.904 (p=0.001), 2.896 (p<0.001) and 3.228 (p<0.001), respectively. The between-group differences in the risk of anti-TB drug resistance were analyzed based on data from three provinces in China. After adding HbA1c grading, the predictive model for MDR (https://mengyuan.shinyapps.io/Shinyapp/) showed excellent capacity with an AUC of 75.4% in the training set (Sichuan and Gansu) and 73.9% in the internal validation set (Henan). The performances in calibration, prediction probabilities and net clinical benefit were significantly improved by HbA1c grading.. HbA1c grading was an independent risk factor for isoniazid resistance and MDR in TB-T2DM patients.

Topics: Adult; Aged; Antitubercular Agents; Diabetes Mellitus, Type 2; Drug Resistance, Bacterial; Drug Resistance, Multiple, Bacterial; Female; Glycated Hemoglobin; Humans; Isoniazid; Male; Middle Aged; Mycobacterium tuberculosis; Odds Ratio; Rifampin; Risk Factors; Tuberculosis; Tuberculosis, Multidrug-Resistant

Tuberculosis (TB) updates and guidelines have been published rapidly in last few years. The WHO and RNTCP have recommended suggestions that have changed the diagnostics and therapeutics paradigm in 2019. The rapid nature of these changes need to be appraised at the pulmonologist end. We conducted a google survey to study these gaps and subsequently review TB in 2019 focusing on the gaps in the survey. We narrate a short review covering the important diagnostic and therapeutic aspects in brief. We discuss the results of our google survey to address the knowledge gaps. Diagnosis, principles and rationale of therapy and treatment of drug sensitive and drug resistant tuberculosis including the shorter regimen and regrouping of drugs are important considerations of our review.

Topics: Antitubercular Agents; Ethambutol; Health Policy; Humans; India; Isoniazid; Molecular Diagnostic Techniques; Nucleic Acid Amplification Techniques; Polymerase Chain Reaction; Practice Guidelines as Topic; Pulmonologists; Pyrazinamide; Rifampin; Surveys and Questionnaires; Tuberculosis; Tuberculosis, Multidrug-Resistant; World Health Organization

The aim of this study was to analyse temporal changes in treatments for and outcomes of multidrug-resistant (MDR)/rifampin-resistant (RR)-tuberculosis (TB) in the context of national economic status.We analysed data collected by the Collaborative Group for the Meta-Analysis of Individual Patient Data in MDR-TB Treatment on MDR/RR-TB patients from 37 countries. The data were stratified by three national income levels (low-/lower-middle, upper-middle and high) and grouped by time of treatment initiation (2001-2003, 2004-2006, 2007-2009, 2010-2012 and 2013-2015). Temporal trends over the study period were analysed. The probability of treatment success in different income groups over time was calculated using generalised linear mixed models with random effects.In total, 9036 patients were included in the analysis. Over the study period, use of group A drugs (levofloxacin/moxifloxacin, bedaquiline and linezolid) recommended by the World Health Organization increased and treatment outcomes improved in all income groups. Between 2001-2003 and 2013-2015, treatment success rates increased from 60% to 78% in low-/lower-middle-income countries, from 40% to 67% in upper-middle-income countries, and from 73% to 81% in high-income countries. In earlier years, the probability of treatment success in upper-middle-income countries was lower than that in low-/lower-middle-income countries, but no difference was observed after 2010. However, high-income countries had persistently higher probability of treatment success compared to upper-middle income countries.Improved treatment outcomes and greater uptake of group A drugs were observed over time for patients with MDR/RR-TB at all income levels. However, treatment outcomes are still unsatisfactory, especially in upper-middle-income countries.

Topics: Antitubercular Agents; Humans; Linezolid; Moxifloxacin; Rifampin; Tuberculosis, Multidrug-Resistant

Drug-resistant tuberculosis burdens fragile health systems in sub-Saharan Africa (SSA), complicated by high prevalence of HIV. Several African countries reported large gaps between estimated incidence and diagnosed or treated cases. Our review aimed to identify barriers and facilitators influencing diagnosis and treatment for drug-resistant tuberculosis (DR-TB) in SSA, which is necessary to develop effective strategies to find the missing incident cases and improve quality of care.. Using an integrative design, we reviewed and narratively synthesised qualitative, quantitative and mixed-methods studies from nine electronic databases: Medline, Global Health, CINAHL, EMBASE, Scopus, Web of Science, International Journal of Tuberculosis and Lung Disease, PubMed and Google Scholar (January 2006 to June 2019).. Of 3181 original studies identified, 55 full texts were screened, and 29 retained. The studies included were from 6 countries, mostly South Africa. Barriers and facilitators to DR-TB care were identified at the health system and patient levels. Predominant health system barriers were laboratory operational issues, provider knowledge and attitudes and information management. Facilitators included GeneXpert MTB/RIF (Xpert) diagnosis and decentralisation of services. At the patient level, predominant barriers were patients being lost to follow-up or dying due to lengthy diagnostic and treatment delays, negative public sector care perceptions, family, work or school commitments and using private sector care. Some patient-level facilitators were HIV positivity and having more symptoms.. Case detection and treatment for DR -TB in SSA currently relies on individual patients presenting voluntarily to the hospital for care. Specific interventions targeting identified barriers may improve rates and timeliness of detection and treatment.

Topics: Humans; Mycobacterium tuberculosis; Rifampin; South Africa; Tuberculosis; Tuberculosis, Multidrug-Resistant

In sub-Saharan Africa (SSA), most prisons are overcrowded with poor ventilation and put prisoners disproportionally at risk of exposure to Mycobacterium tuberculosis (TB) and developing TB infection but are mostly missed due to poor access to healthcare. Active case-finding (ACF) of TB in prisons facilitates early diagnosis and treatment of inmates and prevent the spread. We explored literature and described evidence on TB ACF interventions and approaches for prisoners in SSA prisons.. Guided by the Arksey and O'Malley framework, we searched PubMed, Google Scholar, SCOPUS, Academic search complete, CINAHL and MEDLINE with full text via EBSCOhost for articles on prisoners and ACF from 2000 to May 2019 with no language restriction. Two investigators independently screened the articles at the abstract and full-text stages in parallel guided by the eligibility criteria as well as performed the methodological quality appraisal of the included studies using the latest mixed-method appraisal tool. We extracted all relevant data, organized them into themes and sub-themes, and presented a narrative summary of the results.. Of the 391 eligible articles found, 31 met the inclusion criteria. All 31 articles were published between 2006 and 2019 with the highest six (19.4%) in 2015. We found evidence in 11 countries. That is, Burkina Faso, Cameroon, Coˆte d'Ivoire, the Democratic Republic of the Congo, Ethiopia, Ghana, Malawi, Nigeria, South Africa, Uganda, and Zambia with most 41.9% (13/31) recorded in Ethiopia. These intervention studies were conducted in 134 prisons between 2001 and 2018 using either a single or combination of mass, facility-led, entry, peer educators for routine screening, and exit ACF approaches. The majority (74%) of the studies utilized only a mass screening approach. The most (68%) reported study outcome was smear-positive TB cases only (68%). We found no evidence in 16 SSA countries although they are classified among the three high-burden country lists for TB TB/HIV and Multidrug resistant-TB group.. Our review highlights a dearth of evidence on TB ACF interventions in most SSA countries prisons. Hence, there is the need to scaling-up ACF interventions in SSA prisons, particularly countries included in the three high-burden country lists for TB, TB/HIV, and MDR-TB.

Topics: Africa South of the Sahara; Antibiotics, Antitubercular; Drug Resistance, Multiple, Bacterial; Female; Humans; Male; Mass Screening; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Prevalence; Prisoners; Rifampin; Sputum; Tuberculin Test; Tuberculosis, Multidrug-Resistant

Every year, at least one million children become ill with tuberculosis and around 200,000 children die. Xpert MTB/RIF and Xpert Ultra are World Health Organization (WHO)-recommended rapid molecular tests that simultaneously detect tuberculosis and rifampicin resistance in adults and children with signs and symptoms of tuberculosis, at lower health system levels. To inform updated WHO guidelines on molecular assays, we performed a systematic review on the diagnostic accuracy of these tests in children presumed to have active tuberculosis.. Primary objectives • To determine the diagnostic accuracy of Xpert MTB/RIF and Xpert Ultra for (a) pulmonary tuberculosis in children presumed to have tuberculosis; (b) tuberculous meningitis in children presumed to have tuberculosis; (c) lymph node tuberculosis in children presumed to have tuberculosis; and (d) rifampicin resistance in children presumed to have tuberculosis - For tuberculosis detection, index tests were used as the initial test, replacing standard practice (i.e. smear microscopy or culture) - For detection of rifampicin resistance, index tests replaced culture-based drug susceptibility testing as the initial test Secondary objectives • To compare the accuracy of Xpert MTB/RIF and Xpert Ultra for each of the four target conditions • To investigate potential sources of heterogeneity in accuracy estimates - For tuberculosis detection, we considered age, disease severity, smear-test status, HIV status, clinical setting, specimen type, high tuberculosis burden, and high tuberculosis/HIV burden - For detection of rifampicin resistance, we considered multi-drug-resistant tuberculosis burden • To compare multiple Xpert MTB/RIF or Xpert Ultra results (repeated testing) with the initial Xpert MTB/RIF or Xpert Ultra result SEARCH METHODS: We searched the Cochrane Infectious Diseases Group Specialized Register, MEDLINE, Embase, Science Citation Index, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), Scopus, the WHO International Clinical Trials Registry Platform, ClinicalTrials.gov, and the International Standard Randomized Controlled Trials Number (ISRCTN) Registry up to 29 April 2019, without language restrictions.. Randomized trials, cross-sectional trials, and cohort studies evaluating Xpert MTB/RIF or Xpert Ultra in HIV-positive and HIV-negative children younger than 15 years. Reference standards comprised culture or a composite reference standard for tuberculosis and drug susceptibility testing or MTBDRplus (molecular assay for detection of Mycobacterium tuberculosis and drug resistance) for rifampicin resistance. We included studies evaluating sputum, gastric aspirate, stool, nasopharyngeal or bronchial lavage specimens (pulmonary tuberculosis), cerebrospinal fluid (tuberculous meningitis), fine needle aspirates, or surgical biopsy tissue (lymph node tuberculosis).. Two review authors independently extracted data and assessed study quality using the Quality Assessment of Studies of Diagnostic Accuracy - Revised (QUADAS-2). For each target condition, we used the bivariate model to estimate pooled sensitivity and specificity with 95% confidence intervals (CIs). We stratified all analyses by type of reference standard. We assessed certainty of evidence using the GRADE approach.. For pulmonary tuberculosis, 299 data sets (68,544 participants) were available for analysis; for tuberculous meningitis, 10 data sets (423 participants) were available; for lymph node tuberculosis, 10 data sets (318 participants) were available; and for rifampicin resistance, 14 data sets (326 participants) were available. Thirty-nine studies (80%) took place in countries with high tuberculosis burden. Risk of bias was low except for the reference standard domain, for which risk of bias was unclear because many studies collected only one specimen for culture. Detection of pulmonary tuberculosis For sputum specimens, Xpert MTB/RIF pooled sensitivity (95% CI) and specificity (95% CI) verified by culture were 64.6% (55.3% to 72.9%) (23 studies, 493 participants; moderate-certainty evidence) and 99.0% (98.1% to 99.5%) (23 studies, 6119 participants; moderate-certainty evidence). For other specimen types (nasopharyngeal aspirate, 4 studies; gastric aspirate, 14 studies; stool, 11 studies), Xpert MTB/RIF pooled sensitivity ranged between 45.7% and 73.0%, and pooled specificity ranged between 98.1% and 99.6%. For sputum specimens, Xpert Ultra pooled sensitivity (95% CI) and specificity (95% CI) verified by culture were 72.8% (64.7% to 79.6%) (3 studies, 136 participants; low-certainty evidence) and 97.5% (95.8% to 98.5%) (3 studies, 551 participants; high-certainty evidence). For nasopharyngeal specimens, Xpert Ultra sensitivity (95% CI) and specificity (95% CI) were 45.7% (28.9% to 63.3%) and 97.5% (93.7% to 99.3%) (1 study, 195 participants). For all specimen types, Xpert MTB/RIF and Xpert Ultra sensitivity were lower against a composite reference standard than against culture. Detection of tuberculous meningitis For cerebrospinal fluid, Xpert MTB/RIF pooled sensitivity and specificity, verified by culture, were 54.0% (95% CI 27.8% to 78.2%) (6 studies, 28 participants; very low-certainty evidence) and 93.8% (95% CI 84.5% to 97.6%) (6 studies, 213 participants; low-certainty evidence). Detection of lymph node tuberculosis For lymph node aspirates or biopsies, Xpert MTB/RIF pooled sensitivity and specificity, verified by culture, were 90.4% (95% CI 55.7% to 98.6%) (6 studies, 68 participants; very low-certainty evidence) and 89.8% (95% CI 71.5% to 96.8%) (6 studies, 142 participants; low-certainty evidence). Detection of rifampicin resistance Xpert MTB/RIF pooled sensitivity and specificity were 90.0% (67.6% to 97.5%) (6 studies, 20 participants; low-certainty. We found Xpert MTB/RIF sensitivity to vary by specimen type, with gastric aspirate specimens having the highest sensitivity followed by sputum and stool, and nasopharyngeal specimens the lowest; specificity in all specimens was > 98%. Compared with Xpert MTB/RIF, Xpert Ultra sensitivity in sputum was higher and specificity slightly lower. Xpert MTB/RIF was accurate for detection of rifampicin resistance. Xpert MTB/RIF was sensitive for diagnosing lymph node tuberculosis. For children with presumed tuberculous meningitis, treatment decisions should be based on the entirety of clinical information and treatment should not be withheld based solely on an Xpert MTB/RIF result. The small numbers of studies and participants, particularly for Xpert Ultra, limits our confidence in the precision of these estimates.

Topics: Adolescent; Antibiotics, Antitubercular; Bias; Child; Feces; Gastrointestinal Contents; Humans; Molecular Typing; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Lymph Node; Tuberculosis, Meningeal; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Systematic review of multidrug-resistant tuberculosis (MDR-TB) prevalence among rifampicin (RIF)-resistant tuberculosis (RR-TB) patients in 34 provinces of China was conducted to correlate RIF resistance with concurrent isoniazid (INH) resistance.. Database searches (PubMed, Embase, China National Knowledge Infrastructure, Chinese Scientific Journal, Wanfang), identified drug resistance surveillance studies conducted between January 1, 2000 and June 30, 2018. Of 1554 records, random-effects meta-analysis of 34 studies of adequate methodological quality yielded 108,366 TB cases for MDR-TB prevalence analysis of RR-TB cases.. MDR-TB prevalence among RR-TB cases varied from 57% (Xinjiang; 95% CI 47%, 67%) to 95% (Taiwan; 95% CI 92%, 98%), for a pooled national rate of 77% (95% CI 75%, 80%). Subgroup and meta-regression analyses revealed greater MDR-TB prevalence in previously treated versus new RR-TB cases (P < 0.001), with no significant differences of regional initial drug resistance rates or sampling methods. Regional MDR-TB prevalence among RR-TB cases was lowest (69%) in the Northeast Region (95% CI 65%, 73%) and highest (90%) in Hong Kong, Macao and Taiwan (95% CI 81%, 98%).. In China, ∼77% of RR-TB cases are MDR-TB. Thus, RIF resistance cannot effectively predict MDR-TB. Highly variable RR-TB prevalence across China warrants improved TB management.

Topics: Antitubercular Agents; China; Drug Resistance, Multiple, Bacterial; Geography; Humans; Isoniazid; Mycobacterium tuberculosis; Predictive Value of Tests; Prevalence; Rifampin; Tuberculosis, Multidrug-Resistant

Tuberculosis (TB) being the leading infectious killer in the domain wherein globally, almost 20% of all TB strains are resistant to at least 1 major TB drug and there's a growing incidence of multi-drug resistance tuberculosis (MDR-TB). Looking at the current scenario and challenges the existing strategies fall back in terms of treatment of TB. So, to overcome this new, stronger, improved TB drug pipeline and a new standard for the development of novel anti-TB drugs are required in order to make more drug-resistant and efficient drug which also lower the duration period of the treatment of the TB. This review article aims to highlight the recent developments in the anti-tuberculosis agents, those are currently in the clinical development stage.

Topics: Adamantane; Antitubercular Agents; Diarylquinolines; Drug Development; Drug Therapy, Combination; Duration of Therapy; Ethambutol; Ethylenediamines; Humans; Isoniazid; Macrolides; Medication Adherence; Nitroimidazoles; Oxazolidinones; Pyrazinamide; Rifampin; Tuberculosis, Multidrug-Resistant

The Abbott RealTime MTB (Abbott-RT) and Abbott RealTime MTB RIF/INH Resistance (Abbott-RIF/INH) assays have been introduced for the detection of tuberculosis (TB) and drug-resistant tuberculosis (DR-TB). We performed a systematic review and meta-analysis to assess the accuracy of Abbott-RT and Abbott-RIF/INH for the detection of TB and DR-TB.. The Ovid MEDLINE, EMBASE, Cochrane and Web of Science databases were searched to identify eligible articles for the systematic review. The pooled analyses were calculated with a bivariate model. Hierarchical summary receiver operating characteristic curves and the area under the curve (AUC) were used to summarize overall diagnostic performance. Deeks' test was performed to evaluate potential publication bias.. For the Abbott-RT assay, 9 studies including 3, 640 patients met the study criteria. The pooled sensitivity of Abbott-RT for detecting TB was 0.96 (95% CI: 0.88-0.99) and specificity was 0.97 (95% CI: 0.93-0.99). For DR-TB, four studies were included to evaluate the diagnosis accuracy of Abbott-RIF/INH. The pooled sensitivity was 0.88 (95% CI, 0.82-0.93) and specificity was 0.99 (95% CI, 0.96-0.99). No publication bias was found.. Both Abbott-RT and Abbott-RIF/INH assays have good sensitivity, specificity and accuracy for the diagnosis of TB and DR-TB.

Topics: Anti-Bacterial Agents; Diagnostic Techniques and Procedures; Drug Resistance, Multiple, Bacterial; Humans; Isoniazid; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Topics: Antibiotics, Antitubercular; Drug Resistance, Multiple, Bacterial; Humans; Iran; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Rapid molecular diagnostic methods help in the detection of TB and Rifampicin resistance. These methods detect TB early, are accurate and play a crucial role in reducing the burden of drug resistant tuberculosis. Areas covered: This review analyses rapid molecular diagnostic tools used in the diagnosis of MDR-TB in India, such as the Line Probe Assay and GeneXpert. We have discussed the burden of MDR-TB and the impact of recent diagnostic tools on case detection and treatment outcomes. This review also discusses the costs involved in establishing these new techniques in India. Expert commentary: Molecular methods have considerable advantages for the programmatic management of drug resistant TB. These include speed, standardization of testing, potentially high throughput and reduced laboratory biosafety requirements. There is a desperate need for India to adopt modern, rapid, molecular tools with point-of-care tests being currently evaluated. New molecular diagnostic tests appear to be cost effective and also help in detecting missing cases. There is enough evidence to support the scaling up of these new tools in India.

Topics: Antitubercular Agents; Cost-Benefit Analysis; Early Diagnosis; Humans; India; Molecular Diagnostic Techniques; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Isoniazid-resistant, rifampicin-susceptible (INH-R) tuberculosis is the most common form of drug resistance, and is associated with failure, relapse, and acquired rifampicin resistance if treated with first-line anti-tuberculosis drugs. The aim of the study was to compare success, mortality, and acquired rifampicin resistance in patients with INH-R pulmonary tuberculosis given different durations of rifampicin, ethambutol, and pyrazinamide (REZ); a fluoroquinolone plus 6 months or more of REZ; and streptomycin plus a core regimen of REZ.. Studies with regimens and outcomes known for individual patients with INH-R tuberculosis were eligible, irrespective of the number of patients if randomised trials, or with at least 20 participants if a cohort study. Studies were identified from two relevant systematic reviews, an updated search of one of the systematic reviews (for papers published between April 1, 2015, and Feb 10, 2016), and personal communications. Individual patient data were obtained from authors of eligible studies. The individual patient data meta-analysis was performed with propensity score matched logistic regression to estimate adjusted odds ratios (aOR) and risk differences of treatment success (cure or treatment completion), death during treatment, and acquired rifampicin resistance. Outcomes were measured across different treatment regimens to assess the effects of: different durations of REZ (≤6 months vs >6 months); addition of a fluoroquinolone to REZ (fluoroquinolone plus 6 months or more of REZ vs 6 months or more of REZ); and addition of streptomycin to REZ (streptomycin plus 6 months of rifampicin and ethambutol and 1-3 months of pyrazinamide vs 6 months or more of REZ). The overall quality of the evidence was assessed using GRADE methodology.. Individual patient data were requested for 57 cohort studies and 17 randomised trials including 8089 patients with INH-R tuberculosis. We received 33 datasets with 6424 patients, of which 3923 patients in 23 studies received regimens related to the study objectives. Compared with a daily regimen of 6 months of (H)REZ (REZ with or without isoniazid), extending the duration to 8-9 months had similar outcomes; as such, 6 months or more of (H)REZ was used for subsequent comparisons. Addition of a fluoroquinolone to 6 months or more of (H)REZ was associated with significantly greater treatment success (aOR 2·8, 95% CI 1·1-7·3), but no significant effect on mortality (aOR 0·7, 0·4-1·1) or acquired rifampicin resistance (aOR 0·1, 0·0-1·2). Compared with 6 months or more of (H)REZ, the standardised retreatment regimen (2 months of streptomycin, 3 months of pyrazinamide, and 8 months of isoniazid, rifampicin, and ethambutol) was associated with significantly worse treatment success (aOR 0·4, 0·2-0·7). The quality of the evidence was very low for all outcomes and treatment regimens assessed, owing to the observational nature of most of the data, the diverse settings, and the imprecision of estimates.. In patients with INH-R tuberculosis, compared with treatment with at least 6 months of daily REZ, addition of a fluoroquinolone was associated with better treatment success, whereas addition of streptomycin was associated with less treatment success; however, the quality of the evidence was very low. These results support the conduct of randomised trials to identify the optimum regimen for this important and common form of drug-resistant tuberculosis.. World Health Organization and Canadian Institutes of Health Research.

Topics: Antibiotics, Antitubercular; Cohort Studies; Drug Administration Schedule; Drug Therapy, Combination; Ethambutol; Fluoroquinolones; Humans; Observational Studies as Topic; Outcome Assessment, Health Care; Pyrazinamide; Randomized Controlled Trials as Topic; Review Literature as Topic; Rifampin; Streptomycin; Tuberculosis, Multidrug-Resistant

Use of the Xpert MTB/RIF assay has increased the number of people diagnosed with rifampicin-resistant tuberculosis (RR-TB), especially in South Africa where Xpert is now the initial diagnostic for individuals with TB symptoms. We hypothesized that a proportion of RR-TB patients determined by Xpert can be treated with a rifabutin-containing regimen.. Rifabutin susceptibility by rpoB mutation was assessed in 349 individuals from South Africa and 172 from Belgium. rpoB polymorphisms were identified by Sanger sequencing. Rifampicin and rifabutin susceptibility was assessed phenotypically. A systematic review was performed to comprehensively collate information on rifabutin susceptibility by rpoB polymorphism. Rifabutin susceptibility was assigned to rpoB polymorphisms based on their positive likelihood ratios and ORs.. One hundred and twelve rpoB polymorphisms (67.9% from literature) were identified from all 2045 RR-TB patients, of which 17 polymorphisms could be classified as susceptible/resistant to rifabutin. Eleven polymorphisms were associated with rifabutin susceptibility. The 516GTC mutation was the most common, representing 70% (South Africa) and 76% (Belgium) of all rifabutin-susceptible isolates. At a population level, the 11 polymorphisms associated with rifabutin susceptibility occurred in 33.2% and 16.6% of all South African and Belgian patients diagnosed with RR-TB, respectively.. Identification of the exact rpoB polymorphism leading to the diagnosis of RR-TB has the potential to allow inclusion of rifabutin in the treatment regimen of a substantial proportion of RR-TB patients. A randomized controlled trial evaluating the efficacy of a rifabutin-containing TB treatment regimen in these selected patients is needed to provide the evidence required for a change in policy.

Topics: Antibiotics, Antitubercular; Bacterial Proteins; Belgium; DNA-Directed RNA Polymerases; Humans; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Polymorphism, Genetic; Rifabutin; Rifampin; South Africa; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Biological Assay; China; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

Tuberculosis (TB), which has been a scourge of humanity for thousands of years, is a worldwide pandemic disease caused mainly by Mycobacterium tuberculosis (MTB). The emergence of drug-resistant TB (DR-TB), multidrug-resistant TB (MDR-TB), extensively drug-resistant TB (XDR-TB) and totally drug-resistant TB (TDR-TB) increase the challenges to eliminate TB worldwide. Isoniazid (INH), a critical frontline anti-TB drug, is one of the most effective drugs used to treatment of TB infection for more than 60 years. Unfortunately, bacterial strains resistant to INH are becoming common which mainly due to the long-term widely use even abuse. Therefore, there is an urgent need to develop novel anti-TB agents. Numerous efforts have been undertaken to develop new anti-TB agents, but no new drug has been introduced for more than 5 decades. It has been suggested that the incorporation of lipophilic moieties into the framework of INH can increase permeation of the drug into bacterial cells, thereby enhancing the anti-TB. Therefore, INH derivatives with greater lipophilicity are emerging as one of the most potential anti-TB agents. Indeed, the INH derivative LL-3858 is in initial stages of phase II clinical trial for the treatment of TB and may be approved to treat TB in the near future. This review aims to summarize the recent advances made towards the discovery anti-TB agents holding INH as a nucleus including INH hybrids and INH hydrazide-hydrazone derivatives.

Topics: Animals; Antitubercular Agents; Drug Discovery; Humans; Isoniazid; Mycobacterium tuberculosis; Tuberculosis; Tuberculosis, Multidrug-Resistant

Efforts to control the global burden of tuberculosis (TB) have been jeopardized by the rapid evolution of multi-drug resistant Mycobacterium tuberculosis (MTB), which is resistant to at least isoniazid and rifampicin. Previous studies have documented variable prevalences of multidrug-resistant tuberculosis (MDR-TB) and its risk factors in Ethiopia. Therefore, this meta-analysis is aimed, firstly, to determine the pooled prevalence of MDR-TB among newly diagnosed and previously treated TB cases, and secondly, to measure the association between MDR-TB and a history of previous anti-TB drugs treatment.. PubMed, Embase and Google Scholar databases were searched. Studies that reported a prevalence of MDR-TB among new and previously treated TB patients were selected. Studies or surveys conducted at national or sub-national level, with reported MDR-TB prevalence or sufficient data to calculate prevalence were considered for the analysis. Two authors searched and reviewed the studies for eligibility and extracted the data in pre-defined forms. Forest plots of all prevalence estimates were performed and summary estimates were also calculated using random effects models. Associations between previous TB treatment and MDR-MTB infection were examined through subgroup analyses stratified by new and previously treated patients.. We identified 16 suitable studies and found an overall prevalence of MDR-TB among newly diagnosed and previously treated TB patients to be 2% (95% CI 1% - 2%) and 15% (95% CI 12% - 17%), respectively. The observed difference was statistically significant (P < 0.001) and there was an odds ratio of 8.1 (95% CI 7.5-8.7) for previously treated TB patients to develop a MDR-MTB infection compared to newly diagnosed cases. For the past 10 years (2006 to 2014) the overall MDR-TB prevalence showed a stable time trend.. The burden of MDR-TB remains high in Ethiopian settings, especially in previously treated TB cases. Previous TB treatment was the most powerful predictor for MDR-MTB infection. Strict compliance with anti-TB regimens and improving case detection rate are the necessary steps to tackle the problem in Ethiopia.

Topics: Antitubercular Agents; Ethiopia; Humans; Isoniazid; Mycobacterium tuberculosis; Prevalence; Rifampin; Risk Factors; Tuberculosis, Multidrug-Resistant

Recent studies in addition to studies based on whole genome sequencing (WGS) of clinical isolates of Mycobacterium tuberculosis (MTB) from diverse geographical regions have provided useful insights into the mechanisms of drug resistance. Of importance, are some of the findings pertaining to mechanisms of resistance to two of the first-line anti-tuberculosis (TB) drugs, namely, rifampicin (RIF) and pyrazinamide (PZA). For example, the implication of mutations in rpoA and rpoC genes that act as compensatory mutations for those in the rpoB gene with respect to RIF resistance is noteworthy. Similarly, in the case of PZA resistance, the role of rpsA and panD genes has recently been noted. This highlights the evolving knowledge of resistance to these drugs. The present article provides a detailed account of the molecular mechanisms of resistance against two sterilizing first line anti-TB drugs (RIF and PZA) as well as an overview of sequence-based methods for detection of resistance to the drugs.

Topics: Animals; Antitubercular Agents; Bacteriological Techniques; Drug Resistance, Multiple, Bacterial; Genotype; Humans; Molecular Epidemiology; Mutation; Mycobacterium tuberculosis; Pyrazinamide; Rifampin; Tuberculosis, Multidrug-Resistant; Whole Genome Sequencing

Topics: Antitubercular Agents; Colorimetry; Humans; Isoniazid; Limit of Detection; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Nitrate Reductase; Rifampin; Sensitivity and Specificity; Streptomycin; Tuberculosis, Multidrug-Resistant

The advent of the Xpert® MTB/RIF technique was a revolution in the diagnosis of tuberculosis, especially in areas with high incidence and low resources. It allows the detection of Mycobacterium tuberculosis complex and simultaneously the most common resistance mutations to rifampicin in less than 2h. For respiratory samples the sensitivity is very high, but it decreases for extrapulmonary samples and children. Although it is faster and simpler than conventional methods, it presents some limitations and new and better techniques are needed to reduce the number of cases and deaths caused by tuberculosis. This review aims to assess the scientific evidence around the diagnostic performance of Xpert® MTB/RIF in different types of samples and populations, as well as analyse its strengths and limitations for TB diagnosis.

Topics: Bacterial Proteins; Comorbidity; DNA-Directed RNA Polymerases; DNA, Bacterial; Drug Resistance, Bacterial; Female; HIV Infections; Humans; Incidence; Male; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Rifampin; Sensitivity and Specificity; Tuberculosis; Tuberculosis, Multidrug-Resistant

To reduce transmission and improve patient outcomes, rapid diagnosis and treatment of rifampicin-resistant tuberculosis (RR-TB) is required.. To conduct a systematic review and meta-analysis assessing time to treatment for RR-TB and variability using diagnostic testing methods and treatment delivery approach.. Studies from 2000 to 2015 reporting time to second-line treatment initiation were selected from PubMed and published conference abstracts.. From 53 studies, 83 cohorts (13 034 patients) were included. Overall weighted mean time to treatment from specimen collection was 81 days (95%CI 70-91), and was shorter with ambulatory (57 days, 95%CI 40-74) than hospital-based treatment (86 days, 95%CI 71-102). Time to treatment was shorter with genotypic susceptibility testing (38 days, 95%CI 27-49) than phenotypic testing (108 days, 95%CI 98-117). The mean percentage of diagnosed patients initiating treatment was 76% (95%CI 70-83, range 25-100).. Time to second-line anti-tuberculosis treatment initiation is extremely variable across studies, and often unnecessarily long. Reduced delays are associated with genotypic testing and ambulatory treatment settings. Routine monitoring of the proportion of diagnosed patients initiating treatment and time to treatment are necessary to identify areas for intervention.

Topics: Ambulatory Care; Antitubercular Agents; Genotype; Hospitalization; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Time-to-Treatment; Tuberculosis, Multidrug-Resistant

Drug Resistant Tuberculosis (DRTB) is an emerging problem world-wide. In order to control the disease and decrease the number of cases overtime a prompt diagnosis followed by an appropriate treatment should be provided to patients. Phenotypic DST based on liquid automated culture has greatly reduced the time needed to generate reliable data but has the drawback to be expensive and prone to contamination in the absence of appropriate infrastructures. In the past 10 years molecular biology tools have been developed. Those tools target the main mutations responsible for DRTB and are now globally accessible in term of cost and infrastructures needed for the implementation. The dissemination of the Xpert MTB/rif has radically increased the capacity to perform the detection of rifampicin resistant TB cases. One of the main challenges for the large scale implementation of molecular based tests is the emergence of conflicting results between phenotypic and genotypic tests. This mines the confidence of clinicians in the molecular tests and delays the initiation of an appropriate treatment. A new technique is revolutionizing the genotypic approach to DST: the WGS by Next-Generation Sequencing technologies. This methodology promises to become the solution for a rapid access to universal DST, able indeed to overcome the limitations of the current phenotypic and genotypic assays. Today the use of the generated information is still challenging in decentralized facilities due to the lack of automation for sample processing and standardization in the analysis.The growing knowledge of the molecular mechanisms at the basis of drug resistance and the introduction of high-performing user-friendly tools at peripheral level should allow the very much needed accurate diagnosis of DRTB in the near future.

Topics: Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Evolution, Molecular; Genes, Bacterial; Humans; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Phenotype; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Whole Genome Sequencing

Treatment failure and resistance amplification are common among patients with rifampin-resistant tuberculosis (TB). Drug susceptibility testing (DST) for second-line drugs is recommended for these patients, but logistical difficulties have impeded widespread implementation of second-line DST in many settings. To provide a quantitative perspective on the decision to scale up second-line DST, we synthesize literature on the prevalence of second-line drug resistance, the expected clinical and epidemiologic benefits of using second-line DST to ensure that patients with rifampin-resistant TB receive effective regimens, and the costs of implementing (or not implementing) second-line DST for all individuals diagnosed with rifampin-resistant TB. We conclude that, in most settings, second-line DST could substantially improve treatment outcomes for patients with rifampin-resistant TB, reduce transmission of drug-resistant TB, prevent amplification of drug resistance, and be affordable or even cost-saving. Given the large investment made in each patient treated for rifampin-resistant TB, these payoffs would come at relatively small incremental cost. These anticipated benefits likely justify addressing the real challenges faced in implementing second-line DST in most high-burden settings.

Topics: Antitubercular Agents; Directly Observed Therapy; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Prevalence; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant

Only 25% of multidrug-resistant tuberculosis (MDR-TB) cases are currently diagnosed. Line probe assays (LPAs) enable rapid drug-susceptibility testing for rifampicin (RIF) and isoniazid (INH) resistance and Mycobacterium tuberculosis detection. Genotype MTBDRplusV1 was WHO-endorsed in 2008 but newer LPAs have since been developed.This systematic review evaluated three LPAs: Hain Genotype MTBDRplusV1, MTBDRplusV2 and Nipro NTM+MDRTB. Study quality was assessed with QUADAS-2. Bivariate random-effects meta-analyses were performed for direct and indirect testing. Results for RIF and INH resistance were compared to phenotypic and composite (incorporating sequencing) reference standards. M. tuberculosis detection results were compared to culture.74 unique studies were included. For RIF resistance (21 225 samples), pooled sensitivity and specificity (with 95% confidence intervals) were 96.7% (95.6-97.5%) and 98.8% (98.2-99.2%). For INH resistance (20 954 samples), pooled sensitivity and specificity were 90.2% (88.2-91.9%) and 99.2% (98.7-99.5%). Results were similar for direct and indirect testing and across LPAs. Using a composite reference standard, specificity increased marginally. For M. tuberculosis detection (3451 samples), pooled sensitivity was 94% (89.4-99.4%) for smear-positive specimens and 44% (20.2-71.7%) for smear-negative specimens.In patients with pulmonary TB, LPAs have high sensitivity and specificity for RIF resistance and high specificity and good sensitivity for INH resistance. This meta-analysis provides evidence for policy and practice.

Topics: Antitubercular Agents; DNA Probes; Drug Resistance, Multiple, Bacterial; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Resistance to anti-tuberculosis drugs threatens to undermine effective control of tuberculosis (TB). In areas with weak TB control and misuse of anti-tuberculosis drugs, hotspots of multidrug-resistant TB (MDR-TB) have appeared. The aim of this review is to determine the prevalence rate of any anti-tuberculosis drug resistance, monoresistance and MDR-TB in Ethiopia.. A systematic review of the literature on any resistance, monoresistance and MDR-TB was conducted.. Of the total 468 articles found using electronic search, 14 met the eligibility criteria and were included in the review. The prevalence rate of any drug resistance, polyresistance and MDR-TB was respectively 6.7-72.9%, 0-54% and 0-46%. A higher rate of streptomycin monoresistance (1.5-20.4%) was observed.. The prevalence and distribution of drug-resistant TB remains a serious public health problem in Ethiopia. Rapid, advanced diagnostic tools should be introduced, along with strong treatment and follow-up strategies.

Topics: Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Ethambutol; Ethiopia; Humans; Isoniazid; Prevalence; Public Health; Pyrazinamide; Rifampin; Streptomycin; Tuberculosis, Multidrug-Resistant

A systematic review investigating the role of Xpert MTB/RIF in the diagnosis of tuberculous pleural effusion (TPE) was conducted. The pooled sensitivities and specificities of Xpert MTB/RIF were 51.4% and 98.6%, respectively, with culture used as a reference standard and 22.7% and 99.8%, respectively, with a composite reference standard (CRS) used as the benchmark. Xpert MTB/RIF has low sensitivity but excellent specificity in the diagnosis of TPE.

Topics: Antitubercular Agents; Drug Resistance, Bacterial; Humans; Molecular Diagnostic Techniques; Mycobacterium tuberculosis; Pleural Effusion; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pleural

There is an urgent demand for rapid and accurate drug-susceptibility testing for the detection of multidrug-resistant tuberculosis. The GenoType MTBDRplus assay is a promising molecular kit designed for rapid identification of resistance to first-line anti-tuberculosis drugs, isoniazid and rifampicin. The aim of this meta-analysis was to evaluate the diagnostic accuracy of GenoType MTBDRplus in detecting drug resistance to isoniazid and rifampicin in comparison with the conventional drug susceptibility tests.. We searched PubMed, EMBASE, and Cochrane Library databases to identify studies according to predetermined criteria. A total of 40 studies were included in the meta-analysis. QUADAS-2 was used to assess the quality of included studies with RevMan 5.2. STATA 13.0 software was used to analyze the tests for sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and area under the summary receiver operating characteristic curves. Heterogeneity in accuracy measures was tested with Spearman correlation coefficient and Chi-square.. Patient selection bias was observed in most studies. The pooled sensitivity (95% confidence intervals were 0.91 (0.88-0.94) for isoniazid, 0.96 (0.95-0.97) for rifampicin, and 0.91(0.86-0.94) for multidrug-resistance. The pooled specificity (95% CI) was 0.99 (0.98-0.99) for isoniazid, 0.98 (0.97-0.99) for rifampicin and 0.99 (0.99-1.00) for multidrug-resistance, respectively. The area under the summary receiver operating characteristic curves ranged from 0.99 to 1.00.. This meta-analysis determined that GenoType MTBDRplus had good accuracy for rapid detection of drug resistance to isoniazid and/or rifampicin of M. tuberculosis. MTBDRplus method might be a good alternative to conventional drug susceptibility tests in clinical practice.

Topics: Antitubercular Agents; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; ROC Curve; Tuberculosis, Multidrug-Resistant

A tertiary care hospital in North India.. To determine the prevalence of different genotypes and examine their association with drug resistance among clinical isolates of Mycobacterium tuberculosis from the northern region of India.. We analysed 100 clinical isolates of M. tuberculosis using mycobacterial interspersed repetitive units genotyping and TbD1 analysis.. The analysis revealed that 34% of strains belonged to the Delhi/CAS (TbD1-) lineage, 32% had unknown patterns (27 TbD1-, 5 TbD1+), 18% were of Beijing genotype (TbD1-) and 11% were of EAI lineages (TbD1+). Twenty-one strains were multidrug-resistant tuberculosis (MDR-TB), 9 of which belonged to the Delhi/CAS lineage, 4 were of Beijing lineage, 6 were of unknown pattern and one was of EAI lineage. Our meta-analysis showed the overall proportion of CAS lineage to be 42.96% (95%CI 33-52); the CAS lineage had no association with MDR-TB (OR 0.89, 95%CI 0.66-1.20).. The study highlights the high proportion of CAS lineage strains and absence of association with MDR-TB. The distribution and identification of different genotypes of M. tuberculosis could help in better understanding the factors that influence disease transmission and drug resistance.

Topics: Adolescent; Adult; Aged; Antitubercular Agents; Bacterial Typing Techniques; DNA, Bacterial; Drug Resistance, Multiple, Bacterial; Female; Genetic Loci; Genotyping Techniques; Humans; India; Isoniazid; Male; Middle Aged; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant; Young Adult

Post-exposure prophylaxis (PEP) for leprosy is administered as one single dose of rifampicin (SDR) to the contacts of newly diagnosed leprosy patients. SDR reduces the risk of developing leprosy among contacts by around 60 % in the first 2-3 years after receiving SDR. In countries where SDR is currently being implemented under routine programme conditions in defined areas, questions were raised by health authorities and professional bodies about the possible risk of inducing rifampicin resistance among the M. tuberculosis strains circulating in these areas. This issue has not been addressed in scientific literature to date. To produce an authoritative consensus statement about the risk that SDR would induce rifampicin-resistant tuberculosis, a meeting was convened with tuberculosis (TB) and leprosy experts. The experts carefully reviewed and discussed the available evidence regarding the mechanisms and risk factors for the development of (multi) drug-resistance in M. tuberculosis with a view to the special situation of the use of SDR as PEP for leprosy. They concluded that SDR given to contacts of leprosy patients, in the absence of symptoms of active TB, poses a negligible risk of generating resistance in M. tuberculosis in individuals and at the population level. Thus, the benefits of SDR prophylaxis in reducing the risk of developing leprosy in contacts of new leprosy patients far outweigh the risks of generating drug resistance in M. tuberculosis.

Topics: Drug Resistance, Bacterial; Humans; Leprostatic Agents; Leprosy; Mycobacterium tuberculosis; Post-Exposure Prophylaxis; Rifampin; Risk; Tuberculosis, Multidrug-Resistant

The global roll-out of Xpert MTB/RIF (Cepheid Inc., Sunnyvale, CA, USA) has changed the diagnostic landscape of tuberculosis (TB). More than 16 million tests have been performed in 122 countries since 2011, and detection of multidrug-resistant TB has increased three- to eight-fold compared to conventional testing. The roll-out has galvanised stakeholders, from donors to civil society, and paved the way for universal drug susceptibility testing. It has attracted new product developers to TB, resulting in a robust molecular diagnostics pipeline. However, the roll-out has also highlighted gaps that have constrained scale-up and limited impact on patient outcomes. The roll-out has been hampered by high costs for under-funded programmes, unavailability of a complete solution package (notably comprehensive training, quality assurance, implementation plans, inadequate service and maintenance support) and lack of impact assessment. Insufficient focus has been afforded to effective linkage to care of diagnosed patients, and clinical impact has been blunted by weak health systems. In many countries the private sector plays a dominant role in TB control, yet this sector has limited access to subsidised pricing. In light of these lessons, we advocate for a comprehensive diagnostics implementation approach, including increased engagement of in-country stakeholders for product launch and roll-out, broader systems strengthening in preparation for new technologies, as well as quality impact data from programmatic settings.

Topics: Antibiotics, Antitubercular; Communicable Disease Control; Drug Resistance, Bacterial; Global Health; Health Care Costs; Health Policy; Humans; Mycobacterium tuberculosis; Point-of-Care Testing; Private Sector; Quality Assurance, Health Care; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Compared with smear microscopy, the Xpert MTB/RIF assay (Xpert), with superior accuracy and capacity to diagnose rifampicin resistance, has advanced TB diagnostic capability. However, recent trials of Xpert impact have not demonstrated reductions in patient morbidity and mortality. We conducted a narrative review of Xpert impact trials to summarize which patient-relevant outcomes Xpert has improved and explore reasons for no observed morbidity or mortality reductions. We searched PubMed, Google Scholar, Cochrane Library and Embase and identified eight trials meeting inclusion criteria: three individually randomized, three cluster-randomized, and two pre-post trials. In six trials Xpert increased diagnostic yield of bacteriologically-confirmed TB from sputa and in four trials Xpert shortened time to TB treatment. However, all-cause mortality was similar between arms in all six trials reporting this outcome, and the only trial to assess Xpert impact on morbidity reported no impact. Trial characteristics that might explain lack of observed impact on morbidity and mortality include: higher rates of empiric TB treatment in microscopy compared with Xpert arms, enrollment of study populations not comprised exclusively of populations most likely to benefit from Xpert, and health system weaknesses. So far as equipoise exists, future trials that address past limitations are needed to inform Xpert use in resource-limited settings.

Topics: Antitubercular Agents; Bacterial Typing Techniques; Drug Resistance, Bacterial; HIV Infections; Humans; Mycobacterium tuberculosis; Patient Selection; Polymerase Chain Reaction; Rifampin; Sputum; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Human immunodeficiency virus (HIV) epidemic has undoubtedly increased the incidence of tuberculosis (TB) globally, posing a formidable global health challenge affecting 1.2 million cases. Pulmonary TB assumes utmost significance in the programmatic perspective as it is readily transmissible as well as easily diagnosable. HIV complicates every aspect of pulmonary tuberculosis from diagnosis to treatment, demanding a different approach to effectively tackle both the diseases. In order to control these converging epidemics, it is important to diagnose early, initiate appropriate therapy for both infections, prevent transmission and administer preventive therapy. Liquid culture methods and nucleic acid amplification tests for TB confirmation have replaced conventional solid media, enabling quicker and simultaneous detection of mycobacterium and its drug sensitivity profile Unique problems posed by the syndemic include Acquired rifampicin resistance, drug-drug interactions, malabsorption of drugs and immune reconstitution inflammatory syndrome or paradoxical reaction that complicate dual and concomitant therapy. While the antiretroviral therapy armamentarium is constantly reinforced by discovery of newer and safer drugs every year, only a few drugs for anti tuberculosis treatment have successfully emerged. These include bedaquiline, delamanid and pretomanid which have entered phase III B trials and are also available through conditional access national programmes. The current guidelines by WHO to start Antiretroviral therapy irrespective of CD4+ cell count based on benefits cited by recent trials could go a long way in preventing various complications caused by the deadly duo. This review provides a consolidated gist of the advancements, concepts and updates that have emerged in the management of HIV-associated pulmonary TB for maximizing efficacy, offering latest solutions for tackling drug-drug interactions and remedial measures for immune reconstitution inflammatory syndrome.

Topics: Anti-Retroviral Agents; Antitubercular Agents; Coinfection; Drug Interactions; HIV Infections; Humans; Mycobacterium tuberculosis; Rifampin; Risk Factors; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Topics: Antitubercular Agents; Drug Administration Schedule; Drug Therapy, Combination; Forecasting; Genotype; Global Health; Humans; Isoniazid; Microbial Sensitivity Tests; Palliative Care; Phenotype; Prognosis; Public Health; Rifampin; Risk Factors; Tuberculosis, Multidrug-Resistant

Children were often the forgotten victims of the global tuberculosis (TB) epidemic, neglected by traditional TB services as well as maternal and child health initiatives. Luckily this is changing with a greater focus on children and the issues regarding their optimal management. A common misconception is that children with TB are always difficult to diagnose and treat. New diagnostic tools are urgently needed, but most children with TB in high-burden settings can be diagnosed with available approaches and treatment outcomes are generally excellent. Increased TB awareness, appropriate training of health care workers and inclusion in integrated management of childhood illness strategies will improve the access and quality of care that children receive. This review highlights what needs to be done to ensure that no child unnecessarily dies from TB and provides a brief overview of new advances in the field.

Topics: Antitubercular Agents; BCG Vaccine; Child; Global Health; Health Knowledge, Attitudes, Practice; Humans; Isoniazid; Mycobacterium tuberculosis; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Vaccination

Modern tuberculosis (TB) chemotherapy is widely viewed as a crowning triumph of anti-infectives research. However, only one new TB drug has entered clinical practice in the past 40 years while drug resistance threatens to further destabilize the pandemic. Here, we review a brief history of TB drug development, focusing on the evolution of mechanism(s)-of-action studies and key conceptual barriers to rational, mechanism-based drugs.

Topics: Antitubercular Agents; Diarylquinolines; Drug Design; Drug Resistance, Bacterial; Drug Therapy, Combination; Ethambutol; Evolution, Chemical; Female; Humans; Isoniazid; Male; Mycobacterium tuberculosis; Pyrazinamide; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Prevalence of multidrug resistant tuberculosis (MDR-TB), defined as in vitro resistance to both rifampicin and isoniazid with or without resistance to other TB drugs, in sub-Saharan Africa (SSA) is reportedly low compared to other regions. These estimates are based on data reported to the World Health Organization (WHO) on drug resistance surveys, which may suffer from a reporting bias. We set out to evaluate the variation in prevalence of drug resistant tuberculosis (DR-TB) and its determinants across SSA countries among new and previously treated TB patients.. The aim was to perform a systematic review and meta-analysis of DR-TB prevalence and associated risk factors in SSA. PubMed, EMBASE, Cochrane and bibliographies of DR-TB studies were searched. Surveys at national or sub-national level, with reported DR-TB prevalence (or sufficient data to calculate a prevalence) to isoniazid (INH), rifampicin (RMP), ethambutol (EMB), and streptomycin (SM) conducted in SSA excluding the Republic of South Africa, published between 2003 and 2013 with no language restriction were considered. Two authors searched and reviewed the studies for eligibility and extracted the data in pre-defined forms. Forest plots of all prevalence estimates by resistance outcome were performed. Summary estimates were calculated using random effects models, when appropriate. Associations between any DR-TB and MDR-TB with potential risk factors were examined through subgroup analyses stratified by new and previously treated patients.. A total of 726 studies were identified, of which 27 articles fulfilled the inclusion criteria. Studies reported drug susceptibility testing (DST) results for a total of 13,465 new and 1,776 previously treated TB patients. Pooled estimate of any DR-TB prevalence among the new cases was 12.6% (95% CI 10.6-15.0) while for MDR-TB this was 1.5% (95% CI 1.0-2.3). Among previously treated patients, these were 27.2% (95% CI 21.4-33.8) and 10.3% (95% CI 5.8-17.4%), respectively. DR-TB (any and MDR-TB) did not vary significantly with respect to study characteristics.. The reported prevalence of DR-TB in SSA is low compared to WHO estimates. MDR-TB in this region does not seem to be driven by the high HIV prevalence rates.

Topics: Africa South of the Sahara; Antitubercular Agents; Bacteriological Techniques; Ethambutol; Humans; Isoniazid; Prevalence; Rifampin; Risk Factors; Streptomycin; Tuberculosis, Multidrug-Resistant; World Health Organization

The continuing spread of drug-resistant tuberculosis (TB) is one of the most urgent and difficult challenges facing global TB control. Patients who are infected with strains resistant to isoniazid and rifampicin, called multidrug-resistant (MDR) TB, are practically incurable by standard first-line treatment. In 2012, there were approximately 450,000 new cases and 170,000 deaths because of MDR-TB. Extensively drug-resistant (XDR) TB refers to MDR-TB strains that are resistant to fluoroquinolones and second-line injectable drugs. The main causes of the spread of resistant TB are weak medical systems, amplification of resistance patterns through incorrect treatment, and transmission in communities and facilities. Although patients harboring MDR and XDR strains present a formidable challenge for treatment, cure is often possible with early identification of resistance and use of a properly designed regimen. Community-based programs can improve treatment outcomes by allowing patients to be treated in their homes and addressing socioeconomic barriers to adherence.

Topics: Antitubercular Agents; Child; Coinfection; Community Health Services; Drug Administration Schedule; Drug Design; Drug Therapy, Combination; Extensively Drug-Resistant Tuberculosis; Female; Fluoroquinolones; Global Health; HIV Infections; Humans; Isoniazid; Pregnancy; Pregnancy Complications, Infectious; Rifampin; Tuberculosis, Multidrug-Resistant

Drug-resistant tuberculosis (TB), especially multidrug-resistant (MDR, resistance to rifampicin and isoniazid) disease, is associated with a worse patient outcome. Drug resistance diagnosed using microbiological culture takes days to weeks, as TB bacteria grow slowly. Rapid molecular tests for drug resistance detection (1 day) are commercially available and may promote faster initiation of appropriate treatment.. To (1) conduct a systematic review of evidence regarding diagnostic accuracy of molecular genetic tests for drug resistance, (2) conduct a health-economic evaluation of screening and diagnostic strategies, including comparison of alternative models of service provision and assessment of the value of targeting rapid testing at high-risk subgroups, and (3) construct a transmission-dynamic mathematical model that translates the estimates of diagnostic accuracy into estimates of clinical impact.. A standardised search strategy identified relevant studies from EMBASE, PubMed, MEDLINE, Bioscience Information Service (BIOSIS), System for Information on Grey Literature in Europe Social Policy & Practice (SIGLE) and Web of Science, published between 1 January 2000 and 15 August 2013. Additional 'grey' sources were included. Quality was assessed using quality assessment of diagnostic accuracy studies version 2 (QUADAS-2). For each diagnostic strategy and population subgroup, a care pathway was constructed to specify which medical treatments and health services that individuals would receive from presentation to the point where they either did or did not complete TB treatment successfully. A total cost was estimated from a health service perspective for each care pathway, and the health impact was estimated in terms of the mean discounted quality-adjusted life-years (QALYs) lost as a result of disease and treatment. Costs and QALYs were both discounted at 3.5% per year. An integrated transmission-dynamic and economic model was used to evaluate the cost-effectiveness of introducing rapid molecular testing (in addition to culture and drug sensitivity testing). Probabilistic sensitivity analysis was performed to evaluate the impact on cost-effectiveness of diagnostic and treatment time delays, diagnosis and treatment costs, and associated QALYs.. A total of 8922 titles and abstracts were identified, with 557 papers being potentially eligible. Of these, 56 studies contained sufficient test information for analysis. All three commercial tests performed well when detecting drug resistance in clinical samples, although with evidence of heterogeneity between studies. Pooled sensitivity for GenoType® MTBDRplus (Hain Lifescience, Nehren, Germany) (isoniazid and rifampicin resistance), INNO-LiPA Rif.TB® (Fujirebio Europe, Ghent, Belgium) (rifampicin resistance) and Xpert® MTB/RIF (Cepheid Inc., Sunnyvale, CA, USA) (rifampicin resistance) was 83.4%, 94.6%, 95.4% and 96.8%, respectively; equivalent pooled specificity was 99.6%, 98.2%, 99.7% and 98.4%, respectively. Results of the transmission model suggest that all of the rapid assays considered here, if added to the current diagnostic pathway, would be cost-saving and achieve a reduction in expected QALY loss compared with current practice. GenoType MTBDRplus appeared to be the most cost-effective of the rapid tests in the South Asian population, although results were similar for GeneXpert. In all other scenarios GeneXpert appeared to be the most cost-effective strategy.. Rapid molecular tests for rifampicin and isoniazid resistance were sensitive and specific. They may also be cost-effective when added to culture drug susceptibility testing in the UK. There is global interest in point-of-care testing and further work is needed to review the performance of emerging tests and the wider health-economic impact of decentralised testing in clinics and primary care, as well as non-health-care settings, such as shelters and prisons.. This study is registered as PROSPERO CRD42011001537.. The National Institute for Health Research Health Technology Assessment programme.

Topics: Antitubercular Agents; Bacteriological Techniques; Cost-Benefit Analysis; Drug Resistance, Microbial; Humans; Isoniazid; Models, Econometric; Nucleic Acid Amplification Techniques; Patient Acceptance of Health Care; Quality-Adjusted Life Years; Rifampin; Sequence Analysis; State Medicine; Technology Assessment, Biomedical; Time Factors; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; United Kingdom

Incidence of pulmonary tuberculosis, a contagious infectious disease, decreases in France with 4934 reported cases in 2013. Tuberculosis remains a global health problem as smear is positive in only 50% cases and culture methods require time. In such a context, genotypic diagnostic tools such as Xpert® MTB/RIF gained interest. This rapid and simple-to-use nucleic acid amplification test allows a diagnosis in two hours and prevents further invasive investigations in pulmonary and mediastinal tuberculosis. Because of its low sensitivity, it cannot be used in pleural fluid. Indirect immunologic tests are of no use to diagnose active tuberculosis disease. Another current area of interest is the emergence of resistant tuberculosis. In France, approximately 100 cases of multidrug resistant tuberculosis and a few extensively drug resistant tuberculosis have been reported in 2014. Even though these forms of tuberculosis are imported, it is crucial to identify hazardous situations and to optimize care of these patients. Xpert® MTB/RIF is again of marked interest here as it detects rifampin resistance with a 95% sensitivity and a 98% specificity. Interpretation of genotypic tests such as Genotype® MTBDR or Xpert® MTB/RIF depends on known detected mutations, although they do not always have a clinical or phenotypic expression. In multidrug resistant tuberculosis, the new drug bedaquiline obtained approval for temporarily use in combination with other molecules when there is no other treatment option. Results of bedaquiline are encouraging but adverse events like QT prolongation or the development of new specific drug resistance should convince clinicians to use it with caution.

Topics: Antitubercular Agents; Bacterial Proteins; Bacterial Proton-Translocating ATPases; Diarylquinolines; DNA, Bacterial; France; Genotyping Techniques; Humans; Incidence; Interferon-gamma Release Tests; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Phenotype; Predictive Value of Tests; Rifampin; Sensitivity and Specificity; Sputum; Tuberculin Test; Tuberculosis; Tuberculosis, Multidrug-Resistant

To quantitatively estimate the prevalence of resistance of Mycobacterium tuberculosis (TB) to first line agents in Saudi Arabia.. The overall prevalence of M. tuberculosis resistance was calculated using meta-analysis.. We included 22 studies from Saudi Arabia that were published from 1979 to 2013.A high degree of heterogeneity among studies was observed. Based on random effect methodology, the prevalence (and 95% CI) of the resistance rates were: INH 10.13 (8.13-12.11), rifampicin 5.41 (4.21-6.61), ethambutol 1.29 (1.83-2.37) and streptomycin 6.5 (4.9-8.1), and multi-drug resistant was 6.7 (5.1-8.3).. The prevalence of resistance to anti-tuberculous agents was highest for INH followed by streptomycin and rifampicin. Multi-drug resistant tuberculosis remains at 6.7%. The data support the recommendations to use four anti-tuberculous agents as empiric therapy.

Topics: Antitubercular Agents; Humans; Isoniazid; Mycobacterium tuberculosis; Prevalence; Rifampin; Saudi Arabia; Streptomycin; Tuberculosis, Multidrug-Resistant

To supplement previous state-of-art reviews on anti-tuberculosis treatment and to pave the way forward with reference to the current status, we systematically reviewed published literature on clinical research on tuberculosis (TB) over the past decade in the treatment of drug-susceptible and multidrug-resistant TB (MDR-TB), with a focus on drugs, dosing factors and regimens. Our review was restricted to Phase II/III clinical trials, cohort and case-control studies, and systematic reviews of clinical studies. TB programmatic and patient behavioural factors, non-TB drugs, adjunctive surgery, new vaccines, immunotherapy, antiretroviral therapy and management of latent tuberculous infection are outside the scope of this review. An algorithm was used to systematically search PubMed for relevant articles published in English from 1 January 2005 to 31 December 2014. Articles without evaluated factors (drugs, dosing factors and regimens) or comparative analysis of specified anti-tuberculosis treatment outcomes were excluded. Of the 399 articles initially identified, 294 were excluded. The main findings of the remaining 105 articles are described under two categories: presumed drug-susceptible TB and MDR-TB. Fifty-nine articles included under drug-susceptible TB were divided into 12 subcategories: isoniazid, rifampicin, pyrazinamide, fluoroquinolones, fixed-dose combination drugs, dosing frequency, treatment phases, treatment duration, experimental regimens for pulmonary (surrogate markers vs. clinical outcomes) and extra-pulmonary TB. Forty-nine articles included under MDR-TB were divided into seven subcategories: fluoroquinolones, pyrazinamide, second-line injectable drugs, World Health Organization Group 4 and Group 5 drugs, MDR-TB regimens and novel drugs. Clinical research in the last decade and ongoing trials might furnish new paradigms for improving the treatment of this recalcitrant ancient disease.

Topics: Antitubercular Agents; Biomedical Research; Clinical Trials as Topic; Drug Therapy, Combination; Fluoroquinolones; Humans; Isoniazid; Pyrazinamide; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; World Health Organization

Despite enormous efforts have been made in the hunt for new drugs, tuberculosis (TB) still remains the first bacterial cause of mortality worldwide, causing an estimated 8.6 million new cases and 1.3 million deaths in 2012. Multi-drug resistant-TB strains no longer respond to first-line drugs and are inexorably spreading with an estimated 650,000 cases as well as extensively-drug resistant-TB strains, which are resistant to any fluoroquinolone and at least one of the second-line drugs, with 60,000 cases. Thus the discovery and development of new medicines is a major keystone for tuberculosis treatment and control. After decades of dormancy in the field of TB drug development, recent efforts from various groups have generated a promising TB drug pipeline. Several new therapeutic agents are concurrently studied in clinical trials together with much activity in the hittolead and lead optimization stages. In this article we will review the recent advances in TB drug discovery with a special focus on structure activity relationship studies of the most advanced compound classes.

Topics: Animals; Antitubercular Agents; Humans; Mycobacterium tuberculosis; Structure-Activity Relationship; Tuberculosis; Tuberculosis, Multidrug-Resistant

Tuberculosis (TB) has been a human disease for centuries. Its frequency is increased manyfold in patients with liver cirrhosis. The gold standard of TB management is a 6-mo course of isoniazid, rifampicin, pyrazinamide and ethambutol. Although good results are seen with this treatment in general, the management of patients with underlying cirrhosis is a challenge. The underlying depressed immune response results in alterations in many diagnostic tests. The tests used for latent TB have many flaws in this group of patients. Three of four first-line antitubercular drugs are hepatotoxic and baseline liver function is often disrupted in patients with underlying cirrhosis. Frequency of hepatotoxicity is increased in patients with liver cirrhosis, frequently leading to severe liver failure. There are no established guidelines for the treatment of TB in relation to the severity of liver disease. There is no consensus on the frequency of liver function tests required or the cut-off used to define hepatotoxicity. No specific treatment exists for prevention or treatment of hepatotoxicity, making monitoring even more important. A high risk of multidrug-resistant TB is another major worry due to prolonged and interrupted treatment.

Topics: Antitubercular Agents; Ethambutol; Humans; Immune System Diseases; Isoniazid; Latent Tuberculosis; Liver; Liver Cirrhosis; Liver Diseases; Liver Failure; Liver Function Tests; Liver Transplantation; Prevalence; Pyrazinamide; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant

After the introduction of isoniazid and rifampicin, the second one discovered in the Lepetit Research Laboratories (Milan, Italy), under the supervision of Professor Piero Sensi, tuberculosis (TB) was considered an illness of the past. Unfortunately, this infectious disease is still a global health fear, due to the multidrug-resistant Mycobacterium tuberculosis and extensively circulating drug-resistant strains, as well as the unrecognized TB transmission, especially in regions with high HIV incidence. In the last few years, new antitubercular molecules appeared on the horizon both in preclinical and clinical stage of evaluation. In this review, we focus on a few of them and on their mechanism of action. Two new promising drug targets, DprE1 and MmpL3, are also discussed.

Topics: Alcohol Oxidoreductases; Animals; Antitubercular Agents; Bacterial Proteins; Drug Discovery; Extensively Drug-Resistant Tuberculosis; Humans; Isoniazid; Mycobacterium tuberculosis; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Rapid progress has been made in the development of new diagnostic assays for tuberculosis in recent years. New technologies have been developed and assessed, and are now being implemented. The Xpert MTB/RIF assay, which enables simultaneous detection of Mycobacterium tuberculosis (MTB) and rifampicin (RIF) resistance, was endorsed by WHO in December, 2010. This assay was specifically recommended for use as the initial diagnostic test for suspected drug-resistant or HIV-associated pulmonary tuberculosis. By June, 2012, two-thirds of countries with a high tuberculosis burden and half of countries with a high multidrug-resistant tuberculosis burden had incorporated the assay into their national tuberculosis programme guidelines. Although the development of the Xpert MTB/RIF assay is undoubtedly a landmark event, clinical and programmatic effects and cost-effectiveness remain to be defined. We review the rapidly growing body of scientific literature and discuss the advantages and challenges of using the Xpert MTB/RIF assay in areas where tuberculosis is endemic. We also review other prospects within the developmental pipeline. A rapid, accurate point-of-care diagnostic test that is affordable and can be readily implemented is urgently needed. Investment in the tuberculosis diagnostics pipeline should remain a major priority for funders and researchers.

Topics: AIDS-Related Opportunistic Infections; Antibiotics, Antitubercular; Cost of Illness; Cost-Benefit Analysis; Drug Resistance, Bacterial; Global Health; Health Care Costs; Humans; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Point-of-Care Systems; Predictive Value of Tests; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Topics: Antitubercular Agents; Aza Compounds; Cross-Sectional Studies; Diagnosis, Differential; Diarylquinolines; Fluoroquinolones; Germany; Humans; Moxifloxacin; Nitroimidazoles; Oxazoles; Prognosis; Quinolines; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Rapid tests for rifampicin resistance may be useful for identifying isolates at high risk of drug resistance, including multidrug-resistant TB (MDR-TB). However, choice of diagnostic test and prevalence of rifampicin resistance may both impact a diagnostic strategy for identifying drug resistant-TB. We performed a systematic review to evaluate the performance of WHO-endorsed rapid tests for rifampicin resistance detection.. We searched MEDLINE, Embase and the Cochrane Library through January 1, 2012. For each rapid test, we determined pooled sensitivity and specificity estimates using a hierarchical random effects model. Predictive values of the tests were determined at different prevalence rates of rifampicin resistance and MDR-TB.. We identified 60 publications involving six different tests (INNO-LiPA Rif. TB assay, Genotype MTBDR assay, Genotype MTBDRplus assay, Colorimetric Redox Indicator (CRI) assay, Nitrate Reductase Assay (NRA) and MODS tests): for all tests, negative predictive values were high when rifampicin resistance prevalence was ≤ 30%. However, positive predictive values were considerably reduced for the INNO-LiPA Rif. TB assay, the MTBDRplus assay and MODS when rifampicin resistance prevalence was < 5%.. In many studies, it was unclear whether patient selection or index test performance could have introduced bias. In addition, we were unable to evaluate critical concentration thresholds for the colorimetric tests.. Rapid tests for rifampicin resistance alone cannot accurately predict rifampicin resistance or MDR-TB in areas with a low prevalence of rifampicin resistance. However, in areas with a high prevalence of rifampicin resistance and MDR-TB, these tests may be a valuable component of an MDR-TB management strategy.

Topics: Antitubercular Agents; Bias; Drug Resistance, Multiple, Bacterial; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Predictive Value of Tests; Reagent Kits, Diagnostic; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

In Sub-Saharan Africa, the fight against tuberculosis (TB) has encountered a great challenge because of the emergence of drug resistant TB strains and the high prevalence of HIV infection. The aim of this meta-analysis was to determine the association of drug-resistant TB with anti-TB drug treatment history and HIV co-infection.. After electronic based literature search in the databases of Medline, HINARI, EMBASE and the Cochrane library, article selection and data extraction were carried out. HIV co-infection and previous history of TB treatment were used as predictors for the occurrence of any anti-TB drug resistant or multiple drug resistant TB (MDR-TB). The risk ratios for each included study and for the pooled sample were computed using the random-effects model. Heterogeneity test, sensitivity analyses and funnel plots were also done.. The pooled analysis showed that the risk of developing drug-resistant TB to at least one anti-TB drug was about 3 times higher in individuals who had a previous history of anti-TB treatment than new TB cases. The risk of having MDR-TB in previously anti-TB treated TB cases was more than 5-fold higher than that of new TB cases. Resistance to Ethambutol and Rifampicin was more than fivefold higher among the previously treated with anti-TB drugs. However, HIV infection was not associated with drug-resistant TB.. There was a strong association of previous anti-TB treatment with MDR-TB. Primary treatment warrants special emphasis, and screening for anti-TB drugs sensitivity has to be strengthened.

Topics: Adolescent; Adult; Africa South of the Sahara; Aged; Aged, 80 and over; Antitubercular Agents; Child; Coinfection; Ethambutol; Female; HIV Infections; Humans; Male; Middle Aged; Prevalence; Rifampin; Tuberculosis, Multidrug-Resistant; Young Adult

To review the latest information about levels of anti-tuberculosis (TB) drug resistance in the European Region of the World Health Organization (WHO) and time-trends in multidrug-resistant TB (resistance to isoniazid and rifampicin; MDR-TB) over the past fifteen years. We analysed data on drug resistance among new and previously treated TB cases reported from 1997 to 2012. Data are collected in surveys of representative samples of TB patients or from surveillance systems based on diagnostic drug susceptibility testing. A total of 15.7% (95% confidence limits (CI): 9.5-21.9) of new and 45.3% (95%CI: 39.2-51.5) of previously treated TB cases are estimated to have MDR-TB in the Region. Extensively drug-resistant TB (MDR-TB and resistance to fluoroquinolones and second-line injectables; XDR-TB) had been reported by 38 of the 53 countries of the region (72%). The proportion of MDR-TB cases with XDR-TB is 11.4% (95%CI: 8.6-14.2). Between 1997 and 2012, population rates of MDR-TB declined in Estonia, Latvia and Germany and increased in the United Kingdom, Sweden and Tomsk Oblasts of the Russian Federation. Surveillance of drug resistance has been strengthened in the WHO European Region, which has the highest proportions of MDR-TB and XDR-TB ever reported globally. More complete data are needed particularly from the Russian Federation.

Topics: Antitubercular Agents; Europe; Extensively Drug-Resistant Tuberculosis; Humans; Isoniazid; Microbial Sensitivity Tests; Population Surveillance; Rifampin; Time Factors; Tuberculosis, Multidrug-Resistant; World Health Organization

Multidrug-resistant tuberculosis (MDR TB), defined by resistance to the 2 most effective first-line drugs, isoniazid and rifampin, is on the rise globally and is associated with significant morbidity and mortality. Despite the increasing availability of novel rapid diagnostic tools for Mycobacterium tuberculosis (Mtb) drug susceptibility testing, the clinical applicability of these methods is unsettled. In this study, the mechanisms of action and resistance of Mtb to isoniazid and rifampin, and the utility, advantages and limitations of the available Mtb drug susceptibility testing tools are reviewed, with particular emphasis on molecular methods with rapid turnaround including line probe assays, molecular beacon-based real-time polymerase chain reaction and pyrosequencing. The authors conclude that neither rapid molecular drug testing nor phenotypic methods are perfect in predicting Mtb drug susceptibility and therefore must be interpreted within the clinical context of each patient.

Topics: Animals; Antitubercular Agents; Humans; Isoniazid; Molecular Diagnostic Techniques; Mycobacterium tuberculosis; Rifampin; Sequence Analysis, DNA; Tuberculosis, Multidrug-Resistant

Xpert MTB/RIF (Cepheid) assay has been introduced for the diagnosis of tuberculosis (TB) and RIF-resistance. The meta-analysis was used to establish the overall accuracy of Xpert MTB/RIF assay for diagnosing TB and RIF-resistance.. Based on comprehensive searches of the Pubmed and Embase, we identified outcome data from all articles estimating diagnostic accuracy with Xpert MTB/RIF assay. A summary estimation for sensitivity, specificity, diagnostic odds ratios (DOR) and the area under the summary ROC curve (AUC) was calculated by using the bivariate random-effects approach.. The meta-analysis included 18 studies (10,224 suspected specimens). The summary estimate was 90.4% (95%CI 89.2%-91.4%) for sensitivity, 98.4% (95%CI 98.0%-98.7%) for specificity and 328.3/0.9822 for DOR/AUC in pulmonary tuberculosis (PTB). The sensitivity, specificity and DOR/AUC of detecting RIF-resistance were 94.1%, 97.0% and 177.8/0.9832, respectively. For extrapulmonary tuberculosis, the overall pooled sensitivity was 80.4% and specificity was 86.1%. The findings in subgroup analysis were as follows: the accuracy of Xpert MTB/RIF assay is higher in smear-positive specimens and the sensitivity of diagnosing PTB in adults was higher than that in children (90.8% versus 74.3%).. TB and RIF-resistance can be rapidly and effectively diagnosed with Xpert MTB/RIF assay.

Topics: Adult; Antitubercular Agents; Child; Child, Preschool; Drug Resistance, Bacterial; Humans; Molecular Diagnostic Techniques; Mycobacterium tuberculosis; Predictive Value of Tests; Rifampin; ROC Curve; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

Nine months of daily isoniazid is efficacious in treating latent M. tuberculosis infection, but completion rates are low, limiting treatment effectiveness. In 2011, three important studies were published involving novel regimens for the treatment of latent M. tuberculosis infection. At least 36 months of isoniazid was more effective than 6 months of isoniazid in one study, but not in another-both of which were conducted among tuberculin skin test positive HIV-infected adults living in high tuberculosis incidence settings. Three months of once-weekly isoniazid plus rifapentine or twice-weekly isoniazid plus rifampin (both given under direct observation) resulted in tuberculosis rates similar to those seen with 6 months of isoniazid among HIV-infected persons in high tuberculosis incidence settings. Three months of once-weekly, directly-observed isoniazid plus rifapentine was at least as effective as 9 months of daily isoniazid among predominantly HIV-uninfected persons living in low and medium tuberculosis incidence countries. The 3-month once-weekly isoniazid plus rifapentine regimen demonstrates promise for treatment of latent M. tuberculosis infection in HIV-infected persons.

Topics: AIDS-Related Opportunistic Infections; Anti-HIV Agents; Antitubercular Agents; Drug Administration Schedule; Drug Therapy, Combination; Female; Humans; Isoniazid; Latent Tuberculosis; Male; Rifampin; Time Factors; Treatment Outcome; Tuberculin Test; Tuberculosis, Multidrug-Resistant

Intermittent tuberculosis treatment regimens have been developed to facilitate treatment supervision. Their efficacy has been substantiated by clinical trials and tuberculosis control programmes, notwithstanding the lack of head-to-head comparison between daily and intermittent regimens. Recently, there has been opposing evidence from observational studies, pharmacokinetic-pharmacodynamic studies and animal models that intermittent treatment increases the risk of relapse, treatment failure or acquired rifamycin resistance, especially among HIV-infected patients. Systematic reviews have been conflicting. PubMed, Ovid MEDLINE and EMBASE were systematically searched for publications in English to evaluate the evidence about dosing schedules and treatment efficacy. Levels of evidence and grades of recommendation were assigned largely according to clinical evidence with reference to the Scottish Intercollegiate Guidelines Network guideline development handbook. A total of 32 articles were included after excluding 331 ineligible articles, 42 non-analytical studies, 22 narrative reviews or expert opinions and 44 articles embedded in systematic reviews. These included 9 systematic reviews, 8 controlled studies, 9 pharmacokinetic-pharmacodynamic studies, 5 mouse studies and 1 article about guinea pig experiments. Findings suggest high levels of evidence for using daily dosing schedules, especially during the initial phase in the presence of cavitation, isoniazid resistance and advanced HIV co-infection, to reduce the risk of treatment failure, recurrence and acquired drug resistance including acquired rifamycin resistance. This review justifies the use of daily schedules in standard tuberculosis treatment regimens (particularly in the initial phase), corroborates prevailing understanding of pharmacokinetics-pharmacodynamics and mycobacterial persisters, and supports exploration of rifapentine-containing regimens in higher dosages and frequency.

Topics: AIDS-Related Opportunistic Infections; Animals; Antitubercular Agents; Child; Disease Models, Animal; Drug Administration Schedule; Humans; Isoniazid; Rifampin; Treatment Outcome; Tuberculosis; Tuberculosis, Multidrug-Resistant

Drug-resistant tuberculosis has become a global problem and a major public health concern. While mechanisms of resistance are fairly well characterized for most agents, particularly the first line agents, our knowledge of drug resistance is by no means exhaustive, and strains continue to emerge that carry novel resistance-related mutations. The purpose of this review is to summarize our current understanding of the genetic basis of drug resistance in Mycobacterium tuberculosis, highlighting emerging areas of research. The development of rapid detection methods has been a major breakthrough in the fight against drug-resistant tuberculosis. Rapid detection methods are available for both rifampin- and isoniazid-resistant tuberculosis, but have yet to be developed for other first line agents. Rapid detection methods will become increasingly important as multi-drug resistant strains of M. tuberculosis become more prevalent, even for detecting tuberculosis that is resistant to second line agents.

Topics: Aminoglycosides; Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Ethionamide; Genes, Bacterial; Isoniazid; Molecular Diagnostic Techniques; Mutation; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Tuberculosis (TB) remains a global emergency and is responsible for 1.7 million deaths annually. Widespread global misuse of isoniazid and rifampicin over three decades has resulted in emergence of the ominous spread of multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB) globally. These difficult to treat resistant forms of TB are increasingly seen in Asia, Eastern Europe, South America and sub-Saharan Africa, disrupting TB and HIV control programmes. We review the latest available global epidemiological and clinical evidence on drug-resistant TB in HIV-infected and uninfected populations, with focus on Africa where data are scanty because of poor diagnostic and reporting facilities. The difficult management and infection control problems posed by drug-resistant TB in HIV-infected patients are discussed. Given the increasing current global trends in MDR-TB, aggressive preventive and management strategies are urgently required to avoid disruption of global TB control efforts. The data suggest that existing interventions, public health systems and TB and HIV programmes must be strengthened significantly. Political and funder commitment is essential to curb the spread of drug-resistant TB.

Topics: Africa South of the Sahara; Antitubercular Agents; Asia; Europe, Eastern; Extensively Drug-Resistant Tuberculosis; HIV Infections; Humans; Isoniazid; Rifampin; South America; Tuberculosis, Multidrug-Resistant

To update a previously reported meta-analysis of evidence regarding the diagnostic accuracy and performance characteristics of commercial and non-commercial phage-based assays for the detection of rifampicin (RMP) resistant tuberculosis (TB). DESIGN AND OUTCOMES: We conducted a systematic review and meta-analysis of test accuracy using bivariate random effects regression and hierarchical summary receiver operating characteristics (HSROC) analysis. Tests included the commercial FASTPlaque assays, luciferase reporter phage (LRP) assays, and in-house phage amplification tests. Sensitivity and specificity for RMP resistance were the main outcomes.. By updating previous literature searches, a total of 31 studies (with 3085 specimens) were included in this meta-analysis. Evaluations of commercial phage amplification assays yielded more variable estimates of sensitivity (range 81-100%) and specificity (range 73-100%) compared to evaluations of in-house amplification assays (sensitivity range 88-100%, specificity range 84-100%). LRP evaluations yielded the most consistent estimates of diagnostic accuracy, with seven of eight studies reporting 100% sensitivity and four of eight reporting 100% specificity. Estimates of accuracy failed to capture a major failing of the commercial assay, i.e., the rate of contaminated and indeterminate results. These ranged from 3% to 36% in studies looking at direct detection of RMP resistance from patient specimens (mean 20%).. Phage-based assays will require further development to maximise interpretable results and reduce technical failures. Once technical issues are resolved, impact on patient-important outcomes and cost-effectiveness need to be determined to inform policy for widespread use.

Topics: Antibiotics, Antitubercular; Drug Resistance, Bacterial; Humans; Mycobacteriophages; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

About a third of the world's population has latent tuberculosis. In 2004, over 14 million people had active tuberculosis. Approximately 1.7 million people died from the infection. Over 80% of new cases diagnosed in 2004 were in people in Africa, South-East Asia, and Western Pacific regions.. We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of interventions to prevent tuberculosis in people without HIV infection at high risk of developing tuberculosis? What are the effects of interventions to prevent tuberculosis in people without HIV infection at high risk of developing multidrug-resistant tuberculosis? What are the effects of different drug regimens in people with newly diagnosed pulmonary tuberculosis without HIV infection? What are the effects of different drug regimens in people with multidrug-resistant tuberculosis without HIV infection? What are the effects of low-level laser therapy in people with tuberculosis without HIV infection? Which interventions improve adherence to treatment in people with tuberculosis without HIV infection? We searched: Medline, Embase, The Cochrane Library, and other important databases up to July 2008 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).. We found 31 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.. In this systematic review we present information relating to the effectiveness and safety of the following interventions: adding pyrazinamide in chemotherapy regimens lasting up to 6 months; adding rifampicin to isoniazid regimens; benefits of different regimens; chemotherapy for less than 6 months; daily chemotherapy; direct observation treatment; intermittent chemotherapy for 6 months or longer; isoniazid; low-level laser therapy for pulmonary tuberculosis; regimens containing quinolones; rifampicin plus isoniazid; substituting rifampicin with ethambutol in the continuous phase; and support mechanisms for directly observed treatment.

Topics: Antitubercular Agents; HIV Infections; Humans; Isoniazid; Latent Tuberculosis; Low-Level Light Therapy; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

One of the challenges facing the tuberculosis (TB) control programmes in resource-limited settings is lack of rapid techniques for detection of drug resistant TB, particularly multi drug resistant tuberculosis (MDR TB). Results obtained with the conventional indirect susceptibility testing methods come too late to influence a timely decision on patient management. More rapid tests directly applied on sputum samples are needed. This study compared the sensitivity, specificity and time to results of four direct drug susceptibility testing tests with the conventional indirect testing for detection of resistance to rifampicin and isoniazid in M. tuberculosis. The four direct tests included two in-house phenotypic assays - Nitrate Reductase Assay (NRA) and Microscopic Observation Drug Susceptibility (MODS), and two commercially available tests - Genotype MTBDR and Genotype MTBDRplus (Hain Life Sciences, Nehren, Germany).. A literature review and meta-analysis of study reports was performed. The Meta-Disc software was used to analyse the reports and tests for sensitivity, specificity, and area under the summary receiver operating characteristic (sROC) curves. Heterogeneity in accuracy estimates was tested with the Spearman correlation coefficient and Chi-square.. Eighteen direct DST reports were analysed: NRA - 4, MODS- 6, Genotype MTBDR - 3 and Genotype MTBDRplus - 5. The pooled sensitivity and specificity for detection of resistance to rifampicin were 99% and 100% with NRA, 96% and 96% with MODS, 99% and 98% with Genotype MTBDR, and 99% and 99% with the new Genotype MTBDRplus, respectively. For isoniazid it was 94% and 100% for NRA, 92% and 96% for MODS, 71% and 100% for Genotype MTBDR, and 96% and 100% with the Genotype MTBDRplus, respectively. The area under the summary receiver operating characteristic (sROC) curves was in ranges of 0.98 to 1.00 for all the four tests. Molecular tests were completed in 1 - 2 days and also the phenotypic assays were much more rapid than conventional testing.. Direct testing of rifampicin and isoniazid resistance in M. tuberculosis was found to be highly sensitive and specific, and allows prompt detection of MDR TB.

Topics: Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; ROC Curve; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

The World Health Organization estimates that up to 50 million persons worldwide may be infected with drug resistant strains of TB. The fatality rate of MDR-TB is 20-80%. Drug resistant tuberculosis cases are on the rise in Pakistan. The reasons for this menace are multiple including improper prescription, compliance and over the counter sale of anti-TB drugs. The treatment cost of drug-resistant TB is high, both to the individual patient and society. This article is written to create awareness about the available second line drugs and those in the pipeline. Considering the fact that resistant tuberculosis is difficult to manage, it is suggested that these drugs should only be used after consultation with a physician experienced in the treatment of drug resistant TB. The most frequent mistake made by treating physicians is addition of one drug in the failing regimen. At present, 27 potential anti-TB drugs are at various stages of development. The aim is that by 2010 at least one of these molecules completes the journey and should come in the market.

Topics: Antitubercular Agents; Fluoroquinolones; Humans; Rifabutin; Rifampin; Treatment Failure; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

The current 6-month tuberculosis (TB) therapy is suboptimal with significant side effects and a poor patient compliance problem that frequently selects drug-resistant organisms. The increasing drug-resistant TB problem highlights the need to develop new and more effective drugs. Significant progress has been made recently with several new drug candidates currently in clinical trials. Improved understanding of persister biology and development of persister drugs are likely to be important for developing a more effective therapy.

Topics: Adamantane; AIDS-Related Opportunistic Infections; Animals; Anti-Bacterial Agents; Antitubercular Agents; Drug Administration Schedule; Drug Resistance, Bacterial; Drug Therapy, Combination; Drugs, Investigational; Ethylenediamines; Extensively Drug-Resistant Tuberculosis; Fluoroquinolones; Humans; Isoniazid; Mycobacterium tuberculosis; Nitroimidazoles; Oxazoles; Pyrazinamide; Rifampin; Treatment Refusal; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

In the last decade, multidrug-resistant tuberculosis (MDR-TB, defined as resistance to at least isoniazid and rifampicin) has become an epidemiological issue of first priority at the global level. Case management needs to be simplified and standardised, as in many countries MDR-TB cases cannot receive individualised attention from specialist physicians. However, before any decision can be made on standardisation, a careful analysis must first be made of the evidence and controversies behind the various published recommendations. Unfortunately, the controversies outweigh the evidence. The difficulties lie not only in the absence of controlled trials to validate specific recommendations, but also in the very different and even contradictory results found in the literature. It is therefore essential to analyse these discrepancies before developing rational, uniform recommendations. The analysis should encompass the most essential and controversial issues regarding the management of MDR-TB patients: 1) confirmation of diagnosis in a suspected MDR-TB patient, and determination of the value of drug susceptibility testing; 2) the number of anti-tuberculosis drugs required to treat MDR-TB; 3) the most rational use of effective drugs against tuberculosis; 4) the advisable length of parenteral drug administration or of the initial phase of treatment; 5) the contribution of surgery to the management of MDR-TB patients; and 6) the optimal regimen for treating MDR-TB: standardised vs. individualised regimens. The evidence and controversies regarding each of the above questions are analysed with the aim of facilitating decision making in the treatment of these complex patients.

Topics: Antibiotics, Antitubercular; Case Management; Clinical Trials as Topic; Drug Administration Routes; Humans; Isoniazid; Microbial Sensitivity Tests; Rifampin; Time Factors; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

The two principal characteristics of tuberculosis treatment are its length (several months) and the need to use several antibiotics simultaneously (multiple drug therapy). Multiple drug therapy is intended to prevent the selection of resistant mutants at the beginning of treatment, when the bacilli population is largest. The length of treatment is due to dormant bacilli, which are much more difficult for antibiotics to kill than actively multiplying bacilli are. Rifampin and pyrazinamide are the most potent drugs against these dormant bacilli. The so-called sterilizing activity of rifampin has reduced the duration of treatment from 18 to 9 months, and the contribution of pyrazinamide reduced this time still further, to 6 months. When one of these drugs cannot be used because of resistance or toxicity, duration of treatment increases to the earlier levels. In the extreme case of multidrug-resistant tuberculosis where neither isoniazid nor rifampin can be used, and sometimes even not pyrazinamide, treatment is recommended for 18 to 24 months. New antituberculosis drugs under development allow us to envision further reduction in the duration of treatment of both drug-resistant and drug-sensitive tuberculosis.

Topics: Animals; Antibiotics, Antitubercular; Antitubercular Agents; Disease Models, Animal; Drug Resistance, Bacterial; Drug Resistance, Multiple, Bacterial; Drug Therapy, Combination; Humans; Isoniazid; Mice; Mutation; Mycobacterium tuberculosis; Pyrazinamide; Recurrence; Rifampin; Time Factors; Tuberculosis; Tuberculosis, Multidrug-Resistant

Multidrug-resistant tuberculosis (MDR-TB) is an increasing global problem, with most cases arising from a mixture of physician error and patient non-compliance during treatment of susceptible TB. The extent and burden of MDR-TB varies significantly from country to country and region to region. As with TB itself, the overwhelming burden of MDR-TB is in high-burden resource-poor countries. The diagnosis depends on confirming the drug susceptibility pattern of isolated organisms, which is often only possible in resource-rich settings. There should be a strong suspicion of drug resistance, including MDR-TB, in persons with a history of prior treatment or in treatment failure cases. Treatment in developed countries is expensive and involves an individualized regimen based on drug susceptibility data and use of reserve drugs. In resource-poor settings a WHO retreatment regimen may be used, but increasingly the move is to a directly observed treatment based 'DOTS-plus' regimen in a supported national TB programme. However, even where such treatment is given, the outcome for patients is significantly worse than that for fully susceptible TB and has a much higher cost.

Topics: Antibiotics, Antitubercular; Antitubercular Agents; Developed Countries; Developing Countries; Humans; Isoniazid; Patient Compliance; Rifampin; Risk Factors; Treatment Failure; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

To summarize, using meta-analysis, the accuracy of bacteriophage-based assays for the detection of rifampicin resistance in Mycobacterium tuberculosis.. By searching multiple databases and sources we identified a total of 21 studies eligible for meta-analysis. Of these, 14 studies used phage amplification assays (including eight studies on the commercial FASTPlaque-TB kits), and seven used luciferase reporter phage (LRP) assays. Sensitivity, specificity, and agreement between phage assay and reference standard (e.g. agar proportion method or BACTEC 460) results were the main outcomes of interest.. When performed on culture isolates (N=19 studies), phage assays appear to have relatively high sensitivity and specificity. Eleven of 19 (58%) studies reported sensitivity and specificity estimates > or =95%, and 13 of 19 (68%) studies reported > or =95% agreement with reference standard results. Specificity estimates were slightly lower and more variable than sensitivity; 5 of 19 (26%) studies reported specificity <90%. Only two studies performed phage assays directly on sputum specimens; although one study reported sensitivity and specificity of 100 and 99%, respectively, another reported sensitivity of 86% and specificity of 73%.. Current evidence is largely restricted to the use of phage assays for the detection of rifampicin resistance in culture isolates. When used on culture isolates, these assays appear to have high sensitivity, but variable and slightly lower specificity. In contrast, evidence is lacking on the accuracy of these assays when they are directly applied to sputum specimens. If phage-based assays can be directly used on clinical specimens and if they are shown to have high accuracy, they have the potential to improve the diagnosis of MDR-TB. However, before phage assays can be successfully used in routine practice, several concerns have to be addressed, including unexplained false positives in some studies, potential for contamination and indeterminate results.

Topics: Antibiotics, Antitubercular; Culture Media; Drug Resistance, Bacterial; Humans; Microbial Sensitivity Tests; Mycobacteriophages; Mycobacterium tuberculosis; Reagent Kits, Diagnostic; Rifampin; Sensitivity and Specificity; Time Factors; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Mycobacteria responsible for tuberculosis (M. tuberculosis, M. bovis, M. africanum) are susceptible to a very small number of antibiotics. As soon as these drugs were used in humans all gave rise to the selection of resistant mycobacteria. Study of the mechanisms of acquired resistance, with the help of the genetics of mycobacteria, led to a more accurate understanding of the mode of action of antituberculous drugs. The antibiotics isoniazid, pyrazinamide, ethionamide and ethambutol are mycobacteria-specific because they inhibit the synthesis of mycolic acids, which are specific constituants of the bacterial wall. Mutations responsible for resistance to these drugs affect genes coding for activator enzymes (katg for isoniazid, pncA for pyrazinamide) or genes coding for their target (inhA for isoniazid/ethionamide, embB for ethambutol). With rifamycins, aminosides and quinolones, mechanisms of action and resistance are the same for mycobacteria as for non-mycobacterial organisms. No plasmid or resistance transposon has been described in M. tuberculosis. Currently a test for the quick detection of resistance to rifampicin is widely available but in the future DNA chips may allow the simultaneous detection of multiple resistances. Monitoring of antituberculous drugs shows that in France the prevalence of multiresistance ( resistance to both isoniazid and rifampicin) is 0.5%, primary resistance (before treatment) is 9%, and secondary resistance (after treatment) is 16%.

Topics: Antitubercular Agents; Drug Resistance, Bacterial; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Chemotherapy for tuberculosis is indicated in case of disease as well as in latent tuberculosis infection. Standard medication for drug-susceptible tuberculosis consists of isoniazid and rifampicin for six months with additional pyrazinamide and ethambutol for the first two months. Prolonged treatment is necessary in cases of cavernous pulmonary tuberculosis with lack of negative cultures by two months of therapy, in tuberculosis of the central nervous system and in some cases of superficial lymph node disease. Especially in multiple-drug resistant tuberculosis prolonged treatment with three or more drugs, that have been proven to be effective by susceptability testing, is mandatory. Attention must be payed to reliable delivery of chemotherapy as well as to side effects of antituberculosis medications. The classical treatment for latent tuberculosis infection is isoniazid. Multidrug short-course therapy, which has been shown to be equally effective, enhances patients' compliance, but toxicity is increased.

Topics: Animals; Antitubercular Agents; Drug Administration Schedule; Drug Combinations; Drug Therapy, Combination; Humans; Isoniazid; Practice Patterns, Physicians'; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Progress to understanding the basis of resistance to antituberculous drugs has allowed molecular tests for detection of drug-resistant tuberculosis to be developed. Drug-resistant tuberculosis poses a threat to tuberculosis control programs. It is necessary thus to know drug susceptibilities of individual patient's strain to provide the appropriate drug combinations. Molecular studies on the mechanism of action of antituberculous drugs have elucidated the genetic basis of drug resistance in M. tuberculosis. The mechanisms of drug resistance in tuberculosis are a result of chromosomal mutations in different genes of the bacteria. Upon drug exposure there is a selective pressure for such resistant mutants. Multidrug-resistant tuberculosis is a health problem of increasing significance for the whole global community. This paper reviews the molecular mechanisms associated with drug-resistance as well the new perspectives for detecting resistant isolates.

Topics: Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Ethambutol; Humans; Isoniazid; Mycobacterium tuberculosis; Pyrazinamide; Rifampin; Streptomycin; Tuberculosis, Multidrug-Resistant

Few data address the outcomes of patients who have multidrug-resistant tuberculosis (MDR-TB), defined as resistance to at least isoniazid and rifampin, and who receive a standard World Health Organization (WHO) recommended retreatment regimen after relapse or failure with initial treatment. In this case series, we examined treatment outcomes of a convenience sample of 42 relapse or failure patients who had documented MDR-TB and who had received a standard WHO retreatment regimen (2SHRZE/1HRZE/5H3R3E3). One patient died of tuberculosis in the last month of treatment; the remaining 41 patients completed retreatment. Of the 42, 14 (33%) were sputum smear-negative on completion of therapy. The proportion of patients cured of MDR-TB with the WHO retreatment regimen was similar to historic outcomes when no chemotherapy for TB was given.

Topics: Adolescent; Adult; Antitubercular Agents; Clinical Protocols; Female; Humans; Isoniazid; Male; Middle Aged; Recurrence; Retreatment; Rifampin; Treatment Failure; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Vietnam; World Health Organization

Topics: Antitubercular Agents; Government Programs; Humans; International Cooperation; Isoniazid; National Health Programs; Practice Guidelines as Topic; Rifampin; Tuberculosis, Multidrug-Resistant; World Health Organization

The highest burden of human immunodeficiency virus (HIV) related tuberculosis (TB) is in sub-Saharan Africa. HIV complicates several areas of TB control, one of which involves treatment and treatment outcome. Large patient numbers cause congestion on TB wards, there is increased morbidity, an increased risk of adverse drug reactions, an increased case fatality, and an increased recurrence of TB after treatment completion. TB Control Programmes have responded to these problems by taking actions such as abolishing thioacetazone and decentralising the initial phase of treatment to peripheral health centres and the community. Despite this response, there are three major on-going concerns which need to be addressed by research studies. There is a need to reduce case fatality rates focusing on 1) stronger treatment regimens, 2) adequacy of rifampicin levels when intermittent treatment regimens are used, and 3) adjunctive treatments. There is a need to reduce recurrent rates of TB by 1) determining the relative role of re-infection and reactivation as a cause of recurrence, 2) assessing the importance of duration and type of anti-TB treatment for the first episode of TB, and 3) determining the role of secondary isoniazid preventive therapy. There is a need to evaluate how best to decentralise treatment from the perspective of the health service and the patient. Research studies should be relevant to the needs and resources of TB control programmes, and should include pharmacokinetic studies, controlled clinical trials and operational research, including economic analysis and social science evaluation.

Topics: Africa South of the Sahara; AIDS-Related Opportunistic Infections; Antitubercular Agents; Drug Administration Schedule; Drug Resistance, Bacterial; Drug Therapy, Combination; Government Programs; Humans; Isoniazid; Recurrence; Rifampin; Risk Factors; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Despite continued control efforts, tuberculosis remains a leading cause of illness and death worldwide, with more cases today than at any previous time in history. Not only is there a global increase in the disease itself, there is a worrying rise in the number of cases resistant to the two principal antituberculosis drugs, isoniazid and rifampicin--so called multidrug resistance.

Topics: Antitubercular Agents; Drug Resistance, Bacterial; Global Health; Humans; Isoniazid; Rifampin; Tuberculosis, Multidrug-Resistant

Drug resistant tuberculosis has been recognized since chemotherapy first became available. However, drug resistance has increased in many countries, and recently strains resistant to both rifampicin and isoniazid (multidrug resistant tuberculosis) have emerged. This review discusses the epidemiology of multidrug resistant tuberculosis (MDRTB), and the control of MDRTB in healthcare facilities. Relevant papers for this review were identified by a systematic literature search on Medline. MDRTB is already established world-wide, and although the overall problem of resistance remains low in the UK, it is of significant clinical importance due to its high case-fatality, higher transmission risk, and complex treatment. The key elements of MDRTB control are prompt recognition, confirmation and treatment of cases, and the institution of strict infection control procedures to reduce the airborne spread of infection from infectious patients to others. This review emphasizes the importance of a multidisciplinary approach to management, with liaison between tuberculosis physicians, the microbiology department, infection control team, consultant in communicable disease, and occupational health.

Topics: Antibiotics, Antitubercular; Health Personnel; Humans; Isoniazid; Methicillin Resistance; Occupational Exposure; Rifampin; Staphylococcal Infections; Staphylococcus aureus; Tuberculosis, Multidrug-Resistant

Control of tuberculosis caused by multidrug-resistant (MDR) Mycobacterium (M.) tuberculosis has become one of the major problems throughout the world. Understanding of the molecular mechanisms of resistance may help in the development of novel methods for the rapid and precise detection of drug-resistant M. tuberculosis. Eight agents have been recommended to treat tuberculosis. Isoniazid (INH), rifampicin (RFP), pyrazinamide (PZA), streptomycin(SM), and ethambutol (EB) are used as the first line agents, and the others are the second line agents. MDR M. tuberculosis strains are resistant both to INH and RFP which have the most effective bactericidal activity to M. tuberculosis. Nearly 95% of RFP resistant strains possess a mutation on the rpoB gene encoding a DNA-dependent RNA polymerase. INH particularly shows an inhibition of the cell wall synthesis of M. tuberculosis and approximately 90% of INH resistant strains have a mutation on the inhA, katG, and ahpG gene encoding enzymes related to a mycolic acid synthesis of cell wall. PZA resistant strains have a mutation on the pncA gene encoding a pyrazinamidase which degradates pyrazinamide to a bactericidal substance, pyrazinoic acid. SM resistant strains have a mutation on the rrs and rpsL gene encoding a 16S rRNA and a S12 ribosomal subunit protein, respectively. EB resistant strains have a mutation on the embB gene encoding a arabinosyl transferase which catalyzes cell wall synthesis. Resistant mechanisms of second-line agents have also been identified. Recently, rapid detection methods for RFP and INH resistant mutations have been developed on the basis of these studies.

Topics: Antitubercular Agents; Drug Resistance, Multiple; Ethambutol; Humans; Isoniazid; Mutation; Mycobacterium tuberculosis; Pyrazinamide; Rifampin; Streptomycin; Tuberculosis, Multidrug-Resistant

Topics: AIDS-Related Opportunistic Infections; Anti-HIV Agents; Antitubercular Agents; Disease Susceptibility; HIV Infections; Humans; Polymorphism, Restriction Fragment Length; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Topics: Antibiotics, Antitubercular; Drug Therapy, Combination; Humans; Mycobacterium avium-intracellulare Infection; Rifabutin; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

The discovery of streptomycin in 1944 had given rise to great flowering of chemotherapy for tuberculosis. The times which triple treatment of SM.PAS.INH after the temporal time of SM.PAS had been standard regimens on initial treatment had continued for more than twenty years. The shortening of duration for chemotherapy had become possible by the introduction of RFP, and the duration had reduced to one fourth compared with that of the regimens till then by the addition of PZA for two months at the beginning of treatment on the initial treatment cases. In this paper, historical aspects of early and present-day chemotherapy of tuberculosis and the reports of main studies have been summarized, and pharmacokinetics of INH, action of antituberculous drugs in short-course chemotherapy, MDR-TB and biological response modifiers for treatment of tuberculosis, etc. has been reviewed. It is urgently awaited that more new drugs without cross resistance to previous drugs will be developed for the more shortening of the duration and the improvement of the treatment for MDR-TB.

Topics: Aminosalicylic Acid; Antitubercular Agents; Controlled Clinical Trials as Topic; Drug Delivery Systems; Drug Therapy, Combination; Forecasting; Humans; Immunologic Factors; Isoniazid; Rifampin; Streptomycin; Tuberculosis, Multidrug-Resistant

Multiple drug resistance in mycobacteria compromises the use of antibiotics. Although the genetic and biochemical bases of antibiotic resistance in mycobacteria are largely understood, a number of questions remain to be addressed. This chapter discusses the potential roles of hypermutability and compensatory mutations in establishing stable resistant phenotypes in the pathogenic mycobacteria.

Topics: Amino Acid Sequence; DNA-Directed RNA Polymerases; Drug Resistance, Microbial; Drug Resistance, Multiple; Molecular Sequence Data; Mutation; Mycobacterium; Phenotype; Plant Proteins; Rifampin; Tuberculosis, Multidrug-Resistant

Knowledge of the molecular genetic basis of resistance to antituberculous agents has advanced rapidly since we reviewed this topic 3 years ago. Virtually all isolates resistant to rifampin and related rifamycins have a mutation that alters the sequence of a 27-amino-acid region of the beta subunit of ribonucleic acid (RNA) polymerase. Resistance to isoniazid (INH) is more complex. Many resistant organisms have mutations in the katG gene encoding catalase-peroxidase that result in altered enzyme structure. These structural changes apparently result in decreased conversion of INH to a biologically active form. Some INH-resistant organisms also have mutations in the inhA locus or a recently characterized gene (kasA) encoding a beta-ketoacyl-acyl carrier protein synthase. Streptomycin resistance is due mainly to mutations in the 16S rRNA gene or the rpsL gene encoding ribosomal protein S12. Resistance to pyrazinamide in the great majority of organisms is caused by mutations in the gene (pncA) encoding pyrazinamidase that result in diminished enzyme activity. Ethambutol resistance in approximately 60% of organisms is due to amino acid replacements at position 306 of an arabinosyltransferase encoded by the embB gene. Amino acid changes in the A subunit of deoxyribonucleic acid gyrase cause fluoroquinolone resistance in most organisms. Kanamycin resistance is due to nucleotide substitutions in the rrs gene encoding 16S rRNA. Multidrug resistant strains arise by sequential accumulation of resistance mutations for individual drugs. Limited evidence exists indicating that some drug resistant strains with mutations that severely alter catalase-peroxidase activity are less virulent in animal models. A diverse array of strategies is available to assist in rapid detection of drug resistance-associated gene mutations. Although remarkable advances have been made, much remains to be learned about the molecular genetic basis of drug resistance in Mycobacterium tuberculosis. It is reasonable to believe that development of new therapeutics based on knowledge obtained from the study of the molecular mechanisms of resistance will occur.

Topics: Anti-Bacterial Agents; Anti-Infective Agents; Antibiotics, Antitubercular; Antitubercular Agents; Cycloserine; Drug Resistance, Multiple; Ethambutol; Ethionamide; Fluoroquinolones; Genes, Bacterial; Isoniazid; Mutation; Mycobacterium tuberculosis; Polymorphism, Genetic; Pyrazinamide; Rifampin; Streptomycin; Tuberculosis, Multidrug-Resistant; Virulence

Topics: Antitubercular Agents; Drug Resistance, Multiple; Genes, MDR; Humans; Isoniazid; Mutation; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Tuberculosis is once more a subject of world wide preoccupation; since 1985 a disturbing recrudescence of this disease has been noted in numerous countries related to population growth and the worsening of poverty in those countries without natural resources, and disadvantaged groups living on the margins of society in rich countries, along with the occurrence of an epidemic of HIV (VIH). In numerous developed countries where tuberculosis no longer represents a public health problem, the care services have little by little been closed or re-orientated and the principles of treatment of tuberculosis have been forgotten. The direct consequence of this has often been inadequate treatment and its corollary: the emergence of strains multiresistant to Isoniazid and Rifampicin. If the current epidemiological tendencies are confirmed and no supplementary action is taken, the WHO (OMS) has estimated that during the ten years between 1990 and the millennium there will be 88 million new cases of tuberculosis and 30 million people will die of tuberculosis. However the tendencies can be reversed and tuberculosis could still be eliminated. The struggle against tuberculosis is a world wide emergency and the hope of controlling the situation before an increase in multiresistant strains which would render the trend irreversible, rests on a general application of correct and coherent national programmes. Such a programme as the UICTMR model had already been carried out as has the proof of their efficacy.

Topics: AIDS-Related Opportunistic Infections; Antitubercular Agents; Developed Countries; Developing Countries; Global Health; Health Promotion; HIV Infections; Humans; Incidence; Isoniazid; Population Growth; Poverty; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; World Health Organization

Changing incidence and nature of mycobacterial infections subsequent to the historical regression of tuberculosis and the acquired human immunodeficiency syndrome (AIDS) epidemic, as well as the development of new technical tools for molecular biology, have profoundly modified the methods used for the bacteriological diagnosis of mycobacteria infections. Although microscopic search for acid-fast bacilli, culture and antibiotic resistance tests on Löwenstein-Jensen medium remain the reference methods, more rapid and sophisticated methods are now available. Culture on radiolabeled media using the Bactec system has shortened the delay for positive culture and interpretable antibiotic sensitivity tests. Molecular techniques allow: 1) rapid identification of the most frequently isolated mycobacteria strains, including the most frequent laboratory contaminant M. gordonae, with genome probes; 2) genome typing of M. tuberculosis strains to trace interhuman transmission, detect recurrence or exogenous reinfection or demonstrate laboratory contamination; 3) rapid detection of rifampicin resistance; and 4) direct detection of M. tuberculosis and M. avium in pathological specimens. The role of mycobacteria in the environment causing opportunistic infections, atypical mycobacteria or non-tuberculosis mycobacteria (NTM), particularly the aviaire complex, has grown considerably. Isolation and identification relies on methods used to detect bacilli as well as blood cultures and analysis of fecal matter. NTM are naturally resistant to most of the antituberculosis antibiotics but are sometimes sensitive to aminoglycosides, fluoroquinolones or new macrolides.

Topics: AIDS-Related Opportunistic Infections; Aminoglycosides; Anti-Bacterial Agents; Anti-Infective Agents; Antitubercular Agents; Bacteriological Techniques; Culture Media; Drug Resistance, Microbial; Fluoroquinolones; Genome, Bacterial; Humans; Incidence; Macrolides; Microbial Sensitivity Tests; Molecular Biology; Mycobacterium avium; Mycobacterium avium Complex; Mycobacterium avium-intracellulare Infection; Mycobacterium Infections, Nontuberculous; Mycobacterium tuberculosis; Nontuberculous Mycobacteria; Radiopharmaceuticals; Recurrence; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Treatment of tuberculosis has three major goals: healing the patient, preventing selection of resistant strains and control transmission of tuberculosis. A 6 month regimen consisting of isoniazid, rifampin with addition of pyrazinamide for 2 months is the preferred treatment for pulmonary and extra-pulmonary tuberculosis. If resistance to isoniazid is suspected, ethambutol should be added until drug susceptibility studies become available. This treatment is effective in both HIV infected and uniinfected persons. Treatment failure is mostly related to lack of patient adherence to the drug regimen and to multidrug-resistant tuberculosis. The treatment of multidrug-resistant tuberculosis requires second line drugs which are less effective and poorly tolerated. Prevention of resistant tuberculosis needs adequate treatment of each case of tuberculosis and improving of the patient compliance.

Topics: Aged; AIDS-Related Opportunistic Infections; Antitubercular Agents; Child; Clinical Protocols; Drug Combinations; Ethambutol; Follow-Up Studies; HIV Seronegativity; Humans; Isoniazid; Patient Compliance; Patient Education as Topic; Pyrazinamide; Rifampin; Treatment Failure; Tuberculosis; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

This article reviews recent studies conducted outside the United States assessing the efficacy and safety of rifabutin in the treatment of tuberculosis (TB) in HIV-infected patients, in patients with newly diagnosed TB, and in patients with multidrug-resistant TB. A 6-month pilot study of 50 Ugandan patients with TB associated with HIV infection showed that rifabutin and rifampin were similarly effective with regard to conversion of sputum-smear findings (sputum conversion) and in bringing about clinical and radiologic improvement. Compared with rifampin, rifabutin showed potential for reducing the time to sputum conversion for these patients. Multicenter studies in five countries compared two rifabutin dosages (150 mg/d and 300 mg/d) with rifampin as part of a combination regimen for treatment of newly diagnosed TB in 935 patients. Rifabutin compared favorably with rifampin in sputum conversion; administration of 150 mg/d of rifabutin yielded good results and the fewest adverse effects. The use of rifabutin by 270 patients in five countries who had multidrug-resistant TB (approximately 90% of isolates tested were resistant to rifampin and isoniazid) was assessed in another study. For the majority of these patients, signs and symptoms diminished; one-third had bacteriologic conversions.

Topics: AIDS-Related Opportunistic Infections; Antibiotics, Antitubercular; Clinical Trials as Topic; Humans; Pilot Projects; Rifabutin; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Topics: Antitubercular Agents; Developing Countries; Humans; Isoniazid; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

During the last decade, there has been a marked increase in the number of gravity of tuberculosis cases both in developing countries and in industrialized nations. This is, in part, due to the acquired immune deficiency syndrome (AIDS) pandemic, but global economic depression, increased homelessness and declining control programmes have also contributed. One of the more insidious consequences of this resurgence has been the recent emergence and nosocomial transmission of multidrug-resistant strains of Mycobacterium tuberculosis, thus raising the possibility that untreatable forms of the disease may become widespread. Somewhat surprisingly, given the difficulties of working with this slow-growing pathogen, remarkable progress has been made in a relatively short time, in understanding the molecular epidemiology, the genetic basis, and the biochemical mechanisms of drug resistance. Furthermore, a number of promising molecular tools are now available to help counter tuberculosis and to further understanding.

Topics: AIDS-Related Opportunistic Infections; Amino Acid Sequence; Antitubercular Agents; Cross Infection; Developing Countries; Drug Resistance, Multiple; Humans; Microbial Sensitivity Tests; Molecular Sequence Data; Mycobacterium tuberculosis; Polymerase Chain Reaction; Rifampin; Risk Factors; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Tuberculosis (TB) is the single largest killer among infectious diseases. The recent resurgence of TB together with outbreaks of multidrug resistant tuberculosis has focused attention on understanding the mechanisms of such drug resistance. Because of the relative neglect of TB research in the past and late arrival of mycobacterial genetic tools, the molecular mechanisms of drug resistance in TB remained largely unknown until very recently. In this paper we review recent progress on the mechanisms of resistance to three major anti-TB drugs; isoniazid, rifampicin and streptomycin. While the resistance mechanisms for rifampicin and streptomycin are similar to those found in other bacteria, isoniazid susceptibility and resistance is unique to Mycobacterium tuberculosis. So far, mutations in two chromosomal loci, katG and inhA have been found to be involved in isoniazid resistance in TB. Identification and characterization of mutations responsible for resistance opens up new possibilities for rapid detection of drug resistant strains. Molecular understanding of drug resistance and drug action in M. tuberculosis may eventually lead to rational design of new anti-TB drugs.

Topics: Antitubercular Agents; Catalase; Drug Resistance, Microbial; Genes, Bacterial; Humans; Isoniazid; Mycobacterium tuberculosis; Point Mutation; Polymerase Chain Reaction; Rifampin; Streptomycin; Tuberculosis, Multidrug-Resistant

There is a suggestion that drug resistance rates decreased in developing countries over the period 1962-85, while recent data suggest that resistance may be increasing. The initial decrease in resistance appears to be associated with well-functioning National Tuberculosis Control Programmes (NTP), while the recently observed increase may be due either to understaffed, resource-poor programmes or to the effect of the HIV epidemic, or to both. It is possible that the HIV epidemic may overwhelm the NTP, resulting in decreased programme efficiency and ultimately increased drug resistance. Resistance surveillance appears to be a good measure of programme efficiency. For research purposes, primary drug resistance surveys should be done on a sample of relevant patients which includes and distinguishes between HIV-positive and HIV-negative patients. At this time, there is not enough information to warrant a recommendation regarding HIV testing of TB patients for surveillance purposes. In order for resistance surveys to be relevant from the public health perspective, one must know the proportion of patients presenting for treatment having previously received treatment. The meaningful denominator for drug resistance surveys from the programme evaluation perspective should be the number of patients presenting for treatment. For initial drug resistance surveys the measurement should be the number of people never having received prior TB treatment with resistant bacilli, divided by the number of new patients presenting for treatment. For acquired resistance, one should look at all patients who begin treatment with susceptible bacilli who become resistant 6 months later.

Topics: Antitubercular Agents; Culture Media; Drug Resistance, Microbial; Humans; In Vitro Techniques; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant; World Health Organization

The STREAM stage 2 trial assessed two bedaquiline-containing regimens for rifampicin-resistant tuberculosis: a 9-month all-oral regimen and a 6-month regimen containing an injectable drug for the first 2 months. We did a within-trial economic evaluation of these regimens.. STREAM stage 2 was an international, phase 3, non-inferiority randomised trial in which participants with rifampicin-resistant tuberculosis were randomly assigned (1:2:2:2) to the 2011 WHO regimen (terminated early), a 9-month injectable-containing regimen (control regimen), a 9-month all-oral regimen with bedaquiline (oral regimen), or a 6-month regimen with bedaquiline and an injectable for the first 2 months (6-month regimen). We prospectively collected direct and indirect costs and health-related quality of life data from trial participants until week 76 of follow-up. Cost-effectiveness of the oral and 6-month regimens versus control was estimated in four countries (oral regimen) and two countries (6-month regimen), using health-related quality of life for cost-utility analysis and trial efficacy for cost-effectiveness analysis. This trial is registered with ISRCTN, ISRCTN18148631.. 300 participants were included in the economic analyses (Ethiopia, 61; India, 142; Moldova, 51; Uganda, 46). In the cost-utility analysis, the oral regimen was not cost-effective in Ethiopia, India, Moldova, and Uganda from either a provider or societal perspective. In Moldova, the oral regimen was dominant from a societal perspective. In the cost-effectiveness analysis, the oral regimen was likely to be cost-effective from a provider perspective at willingness-to-pay thresholds per additional favourable outcome of more than US$4500 in Ethiopia, $1900 in India, $3950 in Moldova, and $7900 in Uganda, and from a societal perspective at thresholds of more than $15 900 in Ethiopia, $3150 in India, and $4350 in Uganda, while in Moldova the oral regimen was dominant. In Ethiopia and India, the 6-month regimen would cost tuberculosis programmes and participants less than the control regimen and was highly likely to be cost-effective in both cost-utility analysis and cost-effectiveness analysis. Reducing the bedaquiline price from $1·81 to $1·00 per tablet made the oral regimen cost-effective in the provider-perspective cost-utility analysis in India and Moldova and dominate over the control regimen in the provider-perspective cost-effectiveness analysis in India.. At current costs, the oral bedaquiline-containing regimen for rifampicin-resistant tuberculosis is unlikely to be cost-effective in many low-income and middle-income countries. The 6-month regimen represents a cost-effective alternative if injectable use for 2 months is acceptable.. USAID and Janssen Research & Development.

Topics: Antitubercular Agents; Cost-Benefit Analysis; Humans; Quality of Life; Rifampin; Tuberculosis, Multidrug-Resistant

Tuberculosis is usually treated with a 6-month rifampin-based regimen. Whether a strategy involving shorter initial treatment may lead to similar outcomes is unclear.. In this adaptive, open-label, noninferiority trial, we randomly assigned participants with rifampin-susceptible pulmonary tuberculosis to undergo either standard treatment (rifampin and isoniazid for 24 weeks with pyrazinamide and ethambutol for the first 8 weeks) or a strategy involving initial treatment with an 8-week regimen, extended treatment for persistent clinical disease, monitoring after treatment, and retreatment for relapse. There were four strategy groups with different initial regimens; noninferiority was assessed in the two strategy groups with complete enrollment, which had initial regimens of high-dose rifampin-linezolid and bedaquiline-linezolid (each with isoniazid, pyrazinamide, and ethambutol). The primary outcome was a composite of death, ongoing treatment, or active disease at week 96. The noninferiority margin was 12 percentage points.. Of the 674 participants in the intention-to-treat population, 4 (0.6%) withdrew consent or were lost to follow-up. A primary-outcome event occurred in 7 of the 181 participants (3.9%) in the standard-treatment group, as compared with 21 of the 184 participants (11.4%) in the strategy group with an initial rifampin-linezolid regimen (adjusted difference, 7.4 percentage points; 97.5% confidence interval [CI], 1.7 to 13.2; noninferiority not met) and 11 of the 189 participants (5.8%) in the strategy group with an initial bedaquiline-linezolid regimen (adjusted difference, 0.8 percentage points; 97.5% CI, -3.4 to 5.1; noninferiority met). The mean total duration of treatment was 180 days in the standard-treatment group, 106 days in the rifampin-linezolid strategy group, and 85 days in the bedaquiline-linezolid strategy group. The incidences of grade 3 or 4 adverse events and serious adverse events were similar in the three groups.. A strategy involving initial treatment with an 8-week bedaquiline-linezolid regimen was noninferior to standard treatment for tuberculosis with respect to clinical outcomes. The strategy was associated with a shorter total duration of treatment and with no evident safety concerns. (Funded by the Singapore National Medical Research Council and others; TRUNCATE-TB ClinicalTrials.gov number, NCT03474198.).

Topics: Antitubercular Agents; Diarylquinolines; Drug Administration Schedule; Drug Therapy, Combination; Ethambutol; Humans; Isoniazid; Linezolid; Pyrazinamide; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

To develop the 'Stronger Towns Index': a deprivation index that took into account characteristics of areas encompassing towns that may be eligible for redevelopment funding and explore how this index was associated with self-rated health and migration within England between 2001 and 2011.. There were areas in the lowest deciles of Town Strength who did not receive funding. After multiple adjustment, LS members living in areas with higher deciles were significantly more likely (7% to 38%) to report good health than those in the lowest decile in 2001. Remaining in the same decile between 2001 and 2011 was associated with 7% lower odds of good self-rated health in 2011.. It is important to consider health in towns when allocating funding. Areas in the Midlands may have missed out on funding which might help mitigate poor health.. Ferritin levels <30µg/L were associated with unexplained infertility and might be screened in the future. Further studies with a focus on iron deficiency and iron treatment on women with unexplained infertility are warranted.. This EGM provides a valuable resource for researchers, policy-makers and the public to access the available evidence on the determinants of various COVID-19 health-related behaviours. The map can also be used to help guide research commissioning, by evidence synthesis teams and evidence intermediaries to inform policy during the ongoing pandemic and potential future outbreaks of COVID-19 or other respiratory infections. Evidence included in the map will be explored further through a series of systematic reviews examining the strength of the associations between malleable determinants and the uptake and maintenance of individual protective behaviours.. Patients with polymicrobial bloodstream infections are typically critically ill and harbor multidrug-resistant bacteria. Thus, to minimize mortality rate in critically ill patients, changes in infectious flora should be monitored, antibiotics selected reasonably, and invasive procedures reduced.. Altogether, these findings clearly revealed the great potential of the in vitro biological activity of linseed extract as a safe source for combatting multidrug-resistant. In this work, the capture of carbon dioxide using a dense hollow fiber membrane was studied experimentally and theoretically. The factors affecting the flux and recovery of carbon dioxide were studied using a lab-scale system. Experiments were conducted using a mixture of methane and carbon dioxide to simulate natural gas. The effect of changing the CO. Persistent gender and racial disparities in high-impact medical and critical care journals underscore the need to revise policies and strategies to encourage greater diversity in critical care research.. Thirty evaluable patients were enrolled. Median age was 60.5 years. Median follow-up for all patients was 17 months. Ten patients (33%) experienced grade ≥ 3 treatment-related adverse events, the most common being neutropenia and diarrhea; 50% required ≥ 1 dose reduction. The disease control rate was 90% (progressive disease: 10%, partial response: 23%, stable disease: 67%). There was zero treatment-related mortality. Twenty-two patients (73%, 90% CI 57-86; p = 0.008) completed all chemotherapy and surgery. Two patients (9%) who successfully underwent resection had minor postoperative complications. Median length of hospital stay was 4 days. Median RFS was 7.1 months. Median OS for the entire cohort was 24 months and was not reached in patients who underwent surgical resection.. Neoadjuvant treatment with gemcitabine, cisplatin, and nab-paclitaxel is feasible and safe prior to resection of intrahepatic cholangiocarcinoma and does not adversely impact perioperative outcomes.

Topics: Acetogenins; Acute Disease; Acute Kidney Injury; Administration, Intravenous; Aged; Albumins; Alcoholism; Aldehyde Dehydrogenase; Aldehyde Dehydrogenase, Mitochondrial; alpha-Glucosidases; Anemia; Animals; Anthozoa; Anti-Bacterial Agents; Anti-Infective Agents; Antibodies, Bacterial; Antigens, Bacterial; Antihypertensive Agents; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Antioxidants; Apoptosis; Ascites; Asthma; Bacteria; beta-Lactamases; Bile Duct Neoplasms; Bile Ducts, Intrahepatic; Binding Sites; Biological Availability; Biomass; Borderline Personality Disorder; Brain; Brucella abortus; Brucella melitensis; Brucellosis; Calcium; Carbapenems; Case-Control Studies; Caseins; Cattle; CD8-Positive T-Lymphocytes; Ceftaroline; Cell Line; Cell Line, Tumor; Cell Physiological Phenomena; Cell Proliferation; Cephalosporins; Chemotherapy, Adjuvant; China; Chitin; Chlorella; Chlorophyll; Chlorophyll A; Chlorophyta; Cholangiocarcinoma; Cisplatin; Conotoxins; Contrast Media; Conus Snail; Cross-Sectional Studies; Cytokines; Decapodiformes; Deoxycytidine; Diagnostic and Statistical Manual of Mental Disorders; Dietary Fiber; Diterpenes; DNA Methylation; Dogs; Double-Blind Method; Drug Design; Drug Resistance, Bacterial; Drug Resistance, Multiple, Bacterial; Drug Screening Assays, Antitumor; Eicosapentaenoic Acid; Enzyme-Linked Immunosorbent Assay; Epidermis; Escherichia coli; Escherichia coli Infections; Extraintestinal Pathogenic Escherichia coli; Fatty Acids; Fatty Acids, Unsaturated; Fatty Acids, Volatile; Feasibility Studies; Feces; Female; Ferritins; Fluorodeoxyglucose F18; Gastrectomy; Gastrointestinal Microbiome; Gemcitabine; Glomerular Filtration Rate; Glucose; Glycerol; Granulocyte-Macrophage Colony-Stimulating Factor; HeLa Cells; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; Hypoxia-Inducible Factor-Proline Dioxygenases; Immunoassay; Immunoglobulin G; India; Infant, Newborn; Infertility; Inflammation; Intensive Care Units; Iron; Iron Deficiencies; Kidney; Lacticaseibacillus rhamnosus; Laurencia; Leukocytes; Lipids; Liver Cirrhosis; Long Interspersed Nucleotide Elements; Longitudinal Studies; Male; Mesenchymal Stem Cells; Methicillin-Resistant Staphylococcus aureus; Mice; Microalgae; Microbial Sensitivity Tests; Microscopy; Middle Aged; Minerals; Molecular Conformation; Molecular Docking Simulation; Molecular Structure; Mycobacterium tuberculosis; Myeloid Cells; Myeloid-Derived Suppressor Cells; Neoadjuvant Therapy; Neoplasm Recurrence, Local; Nephropidae; Nicotinic Antagonists; Nitrogen; Obesity; Oxaliplatin; Paclitaxel; Panax; Pancreatic Neoplasms; Pancreatitis; Personality; Personality Disorders; Personality Inventory; Photobioreactors; Plant Extracts; Plasmalogens; Plasmids; Polymorphism, Genetic; Polynesia; Positron Emission Tomography Computed Tomography; Positron-Emission Tomography; Prebiotics; Predictive Value of Tests; Prognosis; Prolyl-Hydroxylase Inhibitors; Rabbits; Radiopharmaceuticals; Rats; Rats, Wistar; Receptors, Nicotinic; Recombinant Proteins; Retrospective Studies; Rifampin; Risk Factors; RNA, Ribosomal, 16S; Salinity; Seaweed; Sensitivity and Specificity; Sepsis; Sesquiterpenes; Severity of Illness Index; Shock, Septic; Silicones; Single Photon Emission Computed Tomography Computed Tomography; Skin; Snails; Solubility; Solvents; Sputum; Staphylococcal Infections; Stomach Neoplasms; Stramenopiles; Structure-Activity Relationship; Technetium Tc 99m Exametazime; Technology; Terpenes; Tuberculosis; Tuberculosis, Multidrug-Resistant; Urinary Catheters; Urinary Tract Infections; Vascular Endothelial Growth Factor A; Virulence Factors; Water; Wound Healing

To describe the effect of adaptations to a person-centred care with short oral regimens on retention in care for rifampicin-resistant TB (RR-TB) in Kandahar province, Afghanistan.. The study included people with RR-TB registered in the programme between 01 October 2016 and 18 April 2021. From 19 November 2019, the programme implemented a trial investigating the safety and effectiveness of short oral RR-TB regimens. During the trial, person-centred care was adapted. We included the data from people living with RR-TB treated in the period before and after the care model was adapted and applied Kaplan-Meier statistics to compare rates of retention in care.. Of 236 patients registered in the RR-TB programme, 146 (61.9%) were registered before and 90 (38.1%) after the model of care was adapted. Before adaptations enhancing person-centred care, pre-treatment attrition was 23.3% (n = 34/146), whilst under the adapted care model it was 5.6% (n = 5/90). Attrition on treatment was 22.3% (n = 25/112) before adaptations, whilst during the study period none of the participants were lost-to-follow-up on treatment and 3.3% died (n = 3/90).. As person-centred care delivery and treatment regimens were adapted to better fit-specific contextual challenges and the needs of the target population, retention in care improved amongst people with RR-TB in Kandahar, Afghanistan.

Topics: Adolescent; Adult; Afghanistan; Antitubercular Agents; Female; Humans; Male; Patient-Centered Care; Retention in Care; Rifampin; Tuberculosis, Multidrug-Resistant; Young Adult

Rapid molecular methods such as the line probe assay (LPA) and Xpert® MTB/RIF assay (Xpert) have been recommended by the World Health Organization for drug-resistant tuberculosis (DR-TB) diagnosis. We conducted an interventional trial in DR-TB reference centers in Brazil to evaluate the impact of the use of LPA and Xpert.. Patients with DR-TB were eligible if their drug susceptibility testing results were available to the treating physician at the time of consultation. The standard reference MGITTM 960 was compared with Xpert (arm 1) and LPA (arm 2). Effectiveness was considered as the start of the appropriate TB regimen that matched drug susceptibility testing (DST) and the proportions of culture conversion and favorable treatment outcomes after 6 months.. A higher rate of empirical treatment was observed with MGIT alone than with the Xpert assay (97.0% vs. 45.0%) and LPA (98.2% vs. 67.5%). Patients started appropriate TB treatment more quickly than those in the MGIT group (median 15.0 vs. 40.5 days; p<0.01) in arm 1. Compared to the MGIT group, culture conversion after 6 months was higher for Xpert in arm 1 (90.9% vs. 79.3%, p=0.39) and LPA in arm 2 (80.0% vs. 83.0%, p=0.81).. In the Xpert arm, there was a significant reduction in days to the start of appropriate anti-TB treatment and a trend towards greater culture conversion in the sixth month.

Topics: Antibiotics, Antitubercular; Brazil; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

Globally rifampicin-resistant tuberculosis disease affects around 460,000 people each year. Currently recommended regimens are 9-24 months duration, have poor efficacy and carry significant toxicity. A shorter, less toxic and more efficacious regimen would improve outcomes for people with rifampicin-resistant tuberculosis.. TB-PRACTECAL is an open-label, randomised, controlled, phase II/III non-inferiority trial evaluating the safety and efficacy of 24-week regimens containing bedaquiline and pretomanid to treat rifampicin-resistant tuberculosis. Conducted in Uzbekistan, South Africa and Belarus, patients aged 15 and above with rifampicin-resistant pulmonary tuberculosis and requiring a new course of therapy were eligible for inclusion irrespective of HIV status. In the first stage, equivalent to a phase IIB trial, patients were randomly assigned one of four regimens, stratified by site. Investigational regimens include oral bedaquiline, pretomanid and linezolid. Additionally, two of the regimens also included moxifloxacin (arm 1) and clofazimine (arm 2) respectively. Treatment was administered under direct observation for 24 weeks in investigational arms and 36 to 96 weeks in the standard of care arm. The second stage of the study was equivalent to a phase III trial, investigating the safety and efficacy of the most promising regimen/s. The primary outcome was the percentage of unfavourable outcomes at 72 weeks post-randomisation. This was a composite of early treatment discontinuation, treatment failure, recurrence, lost-to-follow-up and death. The study is being conducted in accordance with ICH-GCP and full ethical approval was obtained from Médecins sans Frontières ethical review board, London School of Hygiene and Tropical Medicine ethical review board as well as ERBs and regulatory authorities at each site.. TB-PRACTECAL is an ambitious trial using adaptive design to accelerate regimen assessment and bring novel treatments that are effective and safe to patients quicker. The trial took a patient-centred approach, adapting to best practice guidelines throughout recruitment. The implementation faced significant challenges from the COVID-19 pandemic. The trial was terminated early for efficacy on the advice of the DSMB and will report on data collected up to the end of recruitment and, additionally, the planned final analysis at 72 weeks after the end of recruitment.. Clinicaltrials.gov NCT02589782. Registered on 28 October 2015.

Topics: Adolescent; Adult; Antibiotics, Antitubercular; Antitubercular Agents; Diarylquinolines; Humans; Linezolid; Pandemics; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Young Adult

The bedaquiline-pretomanid-linezolid regimen has been reported to have 90% efficacy against highly drug-resistant tuberculosis, but the incidence of adverse events with 1200 mg of linezolid daily has been high. The appropriate dose of linezolid and duration of treatment with this agent to minimize toxic effects while maintaining efficacy against highly drug-resistant tuberculosis are unclear.. We enrolled participants with extensively drug-resistant (XDR) tuberculosis (i.e., resistant to rifampin, a fluoroquinolone, and an aminoglycoside), pre-XDR tuberculosis (i.e., resistant to rifampin and to either a fluoroquinolone or an aminoglycoside), or rifampin-resistant tuberculosis that was not responsive to treatment or for which a second-line regimen had been discontinued because of side effects. We randomly assigned the participants to receive bedaquiline for 26 weeks (200 mg daily for 8 weeks, then 100 mg daily for 18 weeks), pretomanid (200 mg daily for 26 weeks), and daily linezolid at a dose of 1200 mg for 26 weeks or 9 weeks or 600 mg for 26 weeks or 9 weeks. The primary end point in the modified intention-to-treat population was the incidence of an unfavorable outcome, defined as treatment failure or disease relapse (clinical or bacteriologic) at 26 weeks after completion of treatment. Safety was also evaluated.. A total of 181 participants were enrolled, 88% of whom had XDR or pre-XDR tuberculosis. Among participants who received bedaquiline-pretomanid-linezolid with linezolid at a dose of 1200 mg for 26 weeks or 9 weeks or 600 mg for 26 weeks or 9 weeks, 93%, 89%, 91%, and 84%, respectively, had a favorable outcome; peripheral neuropathy occurred in 38%, 24%, 24%, and 13%, respectively; myelosuppression occurred in 22%, 15%, 2%, and 7%, respectively; and the linezolid dose was modified (i.e., interrupted, reduced, or discontinued) in 51%, 30%, 13%, and 13%, respectively. Optic neuropathy developed in 4 participants (9%) who had received linezolid at a dose of 1200 mg for 26 weeks; all the cases resolved. Six of the seven unfavorable microbiologic outcomes through 78 weeks of follow-up occurred in participants assigned to the 9-week linezolid groups.. A total of 84 to 93% of the participants across all four bedaquiline-pretomanid-linezolid treatment groups had a favorable outcome. The overall risk-benefit ratio favored the group that received the three-drug regimen with linezolid at a dose of 600 mg for 26 weeks, with a lower incidence of adverse events reported and fewer linezolid dose modifications. (Funded by the TB Alliance and others; ZeNix ClinicalTrials.gov number, NCT03086486.).

Topics: Aminoglycosides; Antitubercular Agents; Diarylquinolines; Fluoroquinolones; Humans; Linezolid; Nitroimidazoles; Rifampin; Risk Assessment; Treatment Outcome; Tuberculosis; Tuberculosis, Multidrug-Resistant

Rifampicin-resistant tuberculosis (RR-TB) remains an important global health problem. Ideally, the complete drug-resistance profile guides individualized treatment for all RR-TB patients, but this is only practised in high-income countries. Implementation of whole genome sequencing (WGS) technologies into routine care in low and middle-income countries has not become a reality due to the expected implementation challenges, including translating WGS results into individualized treatment regimen composition.. This trial is a pragmatic, single-blinded, randomized controlled medical device trial of a WGS-guided automated treatment recommendation strategy for individualized treatment of RR-TB. Subjects are 18 years or older and diagnosed with pulmonary RR-TB in four of the five health districts of the Free State province in South Africa. Participants are randomized in a 1:1 ratio to either the intervention (a WGS-guided automated treatment recommendation strategy for individualized treatment of RR-TB) or control (RR-TB treatment according to the national South African guidelines). The primary effectiveness outcome is the bacteriological response to treatment measured as the rate of change in time to liquid culture positivity during the first 6 months of treatment. Secondary effectiveness outcomes include cure rate, relapse rate (recurrence of RR-TB disease) and TB free survival rate in the first 12 months following RR-TB treatment completion. Additional secondary outcomes of interest include safety, the feasibility of province-wide implementation of the strategy into routine care, and health economic assessment from a patient and health systems perspective.. This trial will provide important real-life evidence regarding the feasibility, safety, cost, and effectiveness of a WGS-guided automated treatment recommendation strategy for individualized treatment of RR-TB. Given the pragmatic nature, the trial will assist policymakers in the decision-making regarding the integration of next-generation sequencing technologies into routine RR-TB care in high TB burden settings.. ClinicalTrials.gov NCT05017324. Registered on August 23, 2021.

Topics: Algorithms; Antitubercular Agents; Clinical Trials, Phase IV as Topic; Humans; Mycobacterium; Neoplasm Recurrence, Local; Pragmatic Clinical Trials as Topic; Randomized Controlled Trials as Topic; Rifampin; Tuberculosis, Multidrug-Resistant

The STREAM stage 1 trial showed that a 9-month regimen for the treatment of rifampicin-resistant tuberculosis was non-inferior to the 20-month 2011 WHO-recommended regimen. In STREAM stage 2, we aimed to compare two bedaquiline-containing regimens with the 9-month STREAM stage 1 regimen.. We did a randomised, phase 3, non-inferiority trial in 13 hospital clinics in seven countries, in individuals aged 15 years or older with rifampicin-resistant tuberculosis without fluoroquinolone or aminoglycoside resistance. Participants were randomly assigned 1:2:2:2 to the 2011 WHO regimen (terminated early), a 9-month control regimen, a 9-month oral regimen with bedaquiline (primary comparison), or a 6-month regimen with bedaquiline and 8 weeks of second-line injectable. Randomisations were stratified by site, HIV status, and CD4 count. Participants and clinicians were aware of treatment-group assignments, but laboratory staff were masked. The primary outcome was favourable status (negative cultures for Mycobacterium tuberculosis without a preceding unfavourable outcome) at 76 weeks; any death, bacteriological failure or recurrence, and major treatment change were considered unfavourable outcomes. All comparisons used groups of participants randomly assigned concurrently. For non-inferiority to be shown, the upper boundary of the 95% CI should be less than 10% in both modified intention-to-treat (mITT) and per-protocol analyses, with prespecified tests for superiority done if non-inferiority was shown. This trial is registered with ISRCTN, ISRCTN18148631.. Between March 28, 2016, and Jan 28, 2020, 1436 participants were screened and 588 were randomly assigned. Of 517 participants in the mITT population, 133 (71%) of 187 on the control regimen and 162 (83%) of 196 on the oral regimen had a favourable outcome: a difference of 11·0% (95% CI 2·9-19·0), adjusted for HIV status and randomisation protocol (p<0·0001 for non-inferiority). By 76 weeks, 108 (53%) of 202 participants on the control regimen and 106 (50%) of 211 allocated to the oral regimen had an adverse event of grade 3 or 4; five (2%) participants on the control regimen and seven (3%) on the oral regimen had died. Hearing loss (Brock grade 3 or 4) was more frequent in participants on the control regimen than in those on the oral regimen (18 [9%] vs four [2%], p=0·0015). Of 134 participants in the mITT population who were allocated to the 6-month regimen, 122 (91%) had a favourable outcome compared with 87 (69%) of 127 participants randomly assigned concurrently to the control regimen (adjusted difference 22·2%, 95% CI 13·1-31·2); six (4%) of 143 participants on the 6-month regimen had grade 3 or 4 hearing loss.. Both bedaquiline-containing regimens, a 9-month oral regimen and a 6-month regimen with 8 weeks of second-line injectable, had superior efficacy compared with a 9-month injectable-containing regimen, with fewer cases of hearing loss.. USAID and Janssen Research & Development.

Topics: CD4 Lymphocyte Count; Drug Therapy, Combination; HIV Infections; Humans; Rifampin; Tuberculosis, Multidrug-Resistant

Rifampicin-resistant tuberculosis (RR-TB) treatment requires combination treatment, which frequently causes serious adverse events and globally results in not much more than 60% treatment success. In Niger, a high cure rate was obtained with a RR-TB treatment strategy based on a second-line injectable drug (SLID)-containing Short Treatment Regimen (STR), with linezolid replacing the SLID in patients with ototoxicity. Given the availability of novel anti-tuberculosis drugs, WHO recommends all-oral RR-TB treatment. Considering the high level of success with the Niger treatment strategy, it would only be justified to replace it in case robust evidence shows that the WHO all-oral bedaquiline/linezolid (BDQ/LZD)-containing STR (experimental arm) performs better than the Niger RR-TB treatment strategy, (control arm) in terms of safety, effectiveness and adherence.. A pragmatic randomised clinical trial (RCT) using stratified block randomisation, conducted between April 2021 and March 2024, prospectively enrols participants diagnosed with RR-TB in one of the four RR-TB units of the nation. Depending of the month in which patients are diagnosed with RR-TB, patients with FQ-susceptible RR-TB are enrolled in either the experimental arm or control arm.. To increase the feasibility of conducting a RCT, embedded in routine activities of all Niger's RR-TB Units, we used a creative trial design. We randomised by monthly blocks, whereby the regimen used changes every month, using the month of RR-TB diagnosis as stratifying variable. This approach was deemed feasible for Niger's national tuberculosis programme, as it simplifies the work of the clinicians running the RR-TB units. Our creative design may serve as an example for other national programs. Findings will inform national and international RR-TB treatment guidelines, and will also strengthen the evidence-base on how to develop robust RR-TB treatment regimens.. Pan African Clinical Trial Register PACTR202203645724919 . Registered on 15 March 2022.

Topics: Antitubercular Agents; Humans; Linezolid; Niger; Randomized Controlled Trials as Topic; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

In patients with rifampin-resistant tuberculosis, all-oral treatment regimens that are more effective, shorter, and have a more acceptable side-effect profile than current regimens are needed.. We conducted an open-label, phase 2-3, multicenter, randomized, controlled, noninferiority trial to evaluate the efficacy and safety of three 24-week, all-oral regimens for the treatment of rifampin-resistant tuberculosis. Patients in Belarus, South Africa, and Uzbekistan who were 15 years of age or older and had rifampin-resistant pulmonary tuberculosis were enrolled. In stage 2 of the trial, a 24-week regimen of bedaquiline, pretomanid, linezolid, and moxifloxacin (BPaLM) was compared with a 9-to-20-month standard-care regimen. The primary outcome was an unfavorable status (a composite of death, treatment failure, treatment discontinuation, loss to follow-up, or recurrence of tuberculosis) at 72 weeks after randomization. The noninferiority margin was 12 percentage points.. Recruitment was terminated early. Of 301 patients in stage 2 of the trial, 145, 128, and 90 patients were evaluable in the intention-to-treat, modified intention-to-treat, and per-protocol populations, respectively. In the modified intention-to-treat analysis, 11% of the patients in the BPaLM group and 48% of those in the standard-care group had a primary-outcome event (risk difference, -37 percentage points; 96.6% confidence interval [CI], -53 to -22). In the per-protocol analysis, 4% of the patients in the BPaLM group and 12% of those in the standard-care group had a primary-outcome event (risk difference, -9 percentage points; 96.6% CI, -22 to 4). In the as-treated population, the incidence of adverse events of grade 3 or higher or serious adverse events was lower in the BPaLM group than in the standard-care group (19% vs. 59%).. In patients with rifampin-resistant pulmonary tuberculosis, a 24-week, all-oral regimen was noninferior to the accepted standard-care treatment, and it had a better safety profile. (Funded by Médecins sans Frontières; TB-PRACTECAL ClinicalTrials.gov number, NCT02589782.).

Topics: Administration, Oral; Adolescent; Adult; Antitubercular Agents; Drug Therapy, Combination; Humans; Linezolid; Moxifloxacin; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

Treatment of multidrug- and rifampin-resistant tuberculosis (MDR/RR-TB) is expensive, labour-intensive, and associated with substantial adverse events and poor outcomes. While most MDR/RR-TB patients do not receive treatment, many who do are treated for 18 months or more. A shorter all-oral regimen is currently recommended for only a sub-set of MDR/RR-TB. Its use is only conditionally recommended because of very low-quality evidence underpinning the recommendation. Novel combinations of newer and repurposed drugs bring hope in the fight against MDR/RR-TB, but their use has not been optimized in all-oral, shorter regimens. This has greatly limited their impact on the burden of disease. There is, therefore, dire need for high-quality evidence on the performance of new, shortened, injectable-sparing regimens for MDR-TB which can be adapted to individual patients and different settings.. endTB is a phase III, pragmatic, multi-country, adaptive, randomized, controlled, parallel, open-label clinical trial evaluating the efficacy and safety of shorter treatment regimens containing new drugs for patients with fluoroquinolone-susceptible, rifampin-resistant tuberculosis. Study participants are randomized to either the control arm, based on the current standard of care for MDR/RR-TB, or to one of five 39-week multi-drug regimens containing newly approved and repurposed drugs. Study participation in all arms lasts at least 73 and up to 104 weeks post-randomization. Randomization is response-adapted using interim Bayesian analysis of efficacy endpoints. The primary objective is to assess whether the efficacy of experimental regimens at 73 weeks is non-inferior to that of the control. A sample size of 750 patients across 6 arms affords at least 80% power to detect the non-inferiority of at least 1 (and up to 3) experimental regimens, with a one-sided alpha of 0.025 and a non-inferiority margin of 12%, against the control in both modified intention-to-treat and per protocol populations.. The lack of a safe and effective regimen that can be used in all patients is a major obstacle to delivering appropriate treatment to all patients with active MDR/RR-TB. Identifying multiple shorter, safe, and effective regimens has the potential to greatly reduce the burden of this deadly disease worldwide.. ClinicalTrials.gov Identifier NCT02754765. Registered on 28 April 2016; the record was last updated for study protocol version 3.3, on 27 August 2019.

Topics: Antitubercular Agents; Bayes Theorem; Humans; Pharmaceutical Preparations; Randomized Controlled Trials as Topic; Rifampin; Tuberculosis, Multidrug-Resistant

Bedaquiline and delamanid are the first drugs of new classes registered for tuberculosis treatment in 40 years. Each can prolong the QTc interval, with maximum effects occurring weeks after drug initiation. The cardiac safety and microbiological activity of these drugs when co-administered are not well-established. Our aim was to characterise the effects of bedaquiline, delamanid, or both on the QTc interval, longitudinally over 6 months of multidrug treatment, among patients with multidrug-resistant or rifampicin-resistant tuberculosis taking multidrug background therapy.. ACTG A5343 is a phase 2, open-label, randomised, controlled trial in which adults with multidrug-resistant or rifampicin-resistant tuberculosis receiving multidrug background treatment were randomly assigned 1:1:1 by centrally, computer-generated randomisation, by means of permuted blocks to receive bedaquiline, delamanid, or both for 24 weeks. Participants were enrolled at TASK in Cape Town and the South African Tuberculosis Vaccine Initiative in Worcester, both in South Africa, and Hospital Maria Auxiliadora in Peru. Individuals with QTc greater than 450 ms were excluded. HIV-positive participants received dolutegravir-based antiretroviral therapy. Clofazimine was disallowed, and levofloxacin replaced moxifloxacin. ECG in triplicate and sputum cultures were done fortnightly. The primary endpoint was mean QTcF change from baseline (averaged over weeks 8-24); cumulative culture conversation at week 8-24 was an exploratory endpoint. Analyses included all participants who initiated study tuberculosis treatment (modified intention-to-treat population). This trial is registered with ClinicalTrials.gov, NCT02583048 and is ongoing.. Between Aug 26, 2016 and July 13, 2018, of 174 screened, 84 participants (28 in each treatment group, and 31 in total with HIV) were enrolled. Two participants did not initiate study treatment (one in the delamanid group withdrew consent and one in the bedaquiline plus delamanid group) did not meet the eligibility criterion). Mean change in QTc from baseline was 12·3 ms (95% CI 7·8-16·7; bedaquiline), 8·6 ms (4·0-13·1; delamanid), and 20·7 ms (16·1-25·3) (bedaquiline plus delamanid). There were no grade 3 or 4 adverse QTc prolongation events and no deaths during study treatment. Cumulative culture conversion by week 8 was 21 (88%) of 24 (95% CI 71-97; bedaquiline), 20 (83%) of 24 (65-95; delamanid), and 19 (95%) of 20 (79-100; bedaquiline plus delamanid) and was 92% (77-99) for bedaquiline, 91% (76-99), for delamanid, and 95% (79-100) for bedaquiline plus delamanid at 24 weeks.. Combining bedaquiline and delamanid has a modest, no more than additive, effect on the QTc interval, and initial microbiology data are encouraging. This study provides supportive evidence for use of these agents together in patients with multidrug-resistant or rifampicin-resistant tuberculosis with normal baseline QTc values.. Division of AIDS, National Institutes of Health.

Topics: Adult; Antitubercular Agents; Diarylquinolines; Drug Therapy, Combination; Electrocardiography; Female; Humans; Male; Nitroimidazoles; Oxazoles; Peru; Rifampin; South Africa; Treatment Outcome; Tuberculosis, Multidrug-Resistant

Tuberculosis patients "resistant to isoniazid and susceptible to rifampicin (Hr-TB)" remain neglected, despite a high burden and poor outcomes. The World Health Organization (WHO) recommends a 6 month regimen consisting of levofloxacin, rifampicin, ethambutol, and pyrazinamide (LRZE) to treat Hr-TB. In contrast, Uzbekistan uses a 9 month regimen (LRZE plus a second-line injectable in the first 3 months). We aimed to assess the treatment outcomes of this novel regimen among Hr-TB patients treated in two regions of Uzbekistan (Fergana and Bukhara) in 2017-2018. We conducted a cohort study involving secondary analysis of routine surveillance data. Of 132 Hr-TB patients, 105 (80%) were successfully treated. Death was the predominant unsuccessful outcome (13, 10%) followed by "treatment failure" (10, 8%) and "lost to follow-up" (4, 2%). High treatment success is an indicator of the potential effectiveness of the novel regimen and adds to the limited global evidence on this issue. However, the sample size was small and there was no comparison group. Since the study was conducted in two regions of Uzbekistan only, the findings have limited generalizability. We recommend future research using an adequate sample size and an appropriate study design (randomized controlled trial or prospective cohort with a control group receiving the WHO-recommended regimen).

Topics: Antitubercular Agents; Cohort Studies; Humans; Isoniazid; Prospective Studies; Rifampin; Treatment Outcome; Tuberculosis; Tuberculosis, Multidrug-Resistant; Uzbekistan

To investigate the factors associated with rifampicin-resistant tuberculosis among drug resistant tuberculosis patients and to determine the correlation of rifampicin-resistant TB with MDR-TB in a high MDR-TB burden province of china.. A retrospective longitudinal analysis on four surveys of anti-TB drug resistance done in 1998, 2003, 2008, and 2013 in Zhejiang province, China. 4289 sputum-smear microscopy positive suspected tuberculosis patients were eligible at 30 investigation points, chosen by stratified random sampling at survey sites from all over the province. Culturing samples in L-J medium and the drug-susceptibility testing for the 4 first-line anti-TB drugs were performed to all patients. Multivariate logistic regression was carried out to determine the factors associated with the rifampicin-resistance in the study population.. Overall, there were 3832 patients with positive mycobacterial cultures, and 2813 of the isolates (73.4%) were susceptible to all 4 first-line drugs. Analysis of rifampin monoresistant (RMR) TB indicated the prevalence was 1.1% in new cases and 3.4% in previously treated cases. Among the 359 rifampicin resistant TB (RR-TB) cases, 279 (77.7%) were also resistant to isoniazid, indicating MDR-TB. From 1998 to 2013, the proportion of MDR-TB among rifampicin-resistant TB cases varied between 80.0% and 87.5% (P for trend: 0.768) among previously treated cases and varied from 68.6% to 79.5% (P for trend: 0.403) among new cases. Among previously treated patients, those who received treatment for less than 6 months were less likely to have drug resistant TB (OR: 0.40, 95% CI: 0.16-0.97) or MDR-TB (OR: 0.24, 95% CI: 0.07-0.81). Patients who received anti-TB treatment in a general hospital were less likely to develop MDR-TB than those treated in a TB clinic (OR: 0.08, 95% CI: 0.01-0.72).. This study highlights a high proportion of RMR-TB among new RR-TB cases in Zhejiang, China. The management of treatment with rapid and accurate diagnosis of MDR-TB other than only relying on RIF susceptibility testing is crucial for improving adherence and outcomes in patients with drug-resistant TB.

Topics: Adolescent; Adult; China; Female; Humans; Longitudinal Studies; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Prevalence; Retrospective Studies; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

A December 2019 WHO rapid communication recommended the use of 9-month all-oral regimens for treating multidrug-resistant tuberculosis (MDR-TB). Besides the clinical benefits, they are thought to be less costly than the injectable-containing regimens, for both the patient and the health system. STREAM is the first randomised controlled trial with an economical evaluation to compare all-oral and injectable-containing 9-11-month MDR-TB treatment regimens.. Health system costs of delivering a 9-month injectable-containing regimen and a 9-month all-oral bedaquiline-containing regimen will be collected in Ethiopia, India, Moldova and Uganda, using 'bottom-up' and 'top-down' costing approaches. Patient costs will be collected using questionnaires that have been developed based on the STOP-TB questionnaire. The primary objective of the study is to estimate the cost utility of the two regimens, from a health system perspective. Secondary objectives include estimating the cost utility from a societal perspective as well as evaluating the cost-effectiveness of the regimens, using both health system and societal perspectives. The effect measure for the cost-utility analysis will be the quality-adjusted life years (QALY), while the effect measure for the cost-effectiveness analysis will be the efficacy outcome from the clinical trial.. The study has been evaluated and approved by the Ethics Advisory Group of the. ISRCTN18148631.

Topics: Antitubercular Agents; Cost-Benefit Analysis; Diarylquinolines; Ethiopia; Humans; India; Moldova; Myocardial Infarction; Rifampin; Tuberculosis, Multidrug-Resistant; Uganda

India has the highest burden of Tuberculosis (TB) and multidrug-resistant TB (MDR-TB) worldwide. Innovative technology is the need of the hour to identify these cases that remain either undiagnosed or inadequately diagnosed due to the unavailability of appropriate tools at primary healthcare settings. We developed and evaluated 3 kits, namely 'TB Detect' (containing BioFM-Filter device), 'TB Concentration and Transport' (containing Trans-Filter device) and 'TB DNA Extraction' kits. These kits enable bio-safe equipment-free concentration of sputum on filters and improved fluorescence microscopy at primary healthcare centres, ambient temperature transport of dried inactivated sputum filters to central laboratories and molecular detection of drug resistance by PCR and DNA sequencing (Mol-DST). In a 2-site evaluation (n = 1190 sputum specimens) on presumptive TB patients, BioFM-Filter smear exhibited a significant increase in positivity of 7% and 4% over ZN smear and LED-FM smear (p<0.05), respectively and an increment in smear grade status (1+ or 2+ to 3+) of 16% over ZN smear and 20% over LED-FM smear. The sensitivity of Mol-DST in presumptive MDR-TB and XDR-TB cases (n = 148) was 90% for Rifampicin (95% confidence interval [CI], 78-96%), 84% for Isoniazid (95% CI, 72-92%), 83% for Fluoroquinolones (95% CI, 66-93%) and 75% for Aminoglycosides (95% CI, 35-97%), using phenotypic DST as the reference standard. Test specificity was 88-93% and concordance was ~89-92% (κ value 0.8-0.9). The patient-friendly kits described here address several of the existing challenges and are designed to provide 'Universal Access' to rapid TB diagnosis, including drug-resistant disease. Their utility was demonstrated by application to sputum at 2 sites in India. Our findings pave the way for larger studies in different point-of-care settings, including high-density urban areas and remote geographical locations.

Topics: Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Fluoroquinolones; Humans; India; Isoniazid; Microscopy, Fluorescence; Mycobacterium tuberculosis; Reagent Kits, Diagnostic; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant

Drug-resistant tuberculosis (DR-TB) remains a major global health problem. Early treatment of TB is critical; in the absence of rapid- susceptibility testing, the empiric selection of drugs should be guided by clinical data. This study aimed to determine the clinical predictors of DR-TB. From September 2010 to August 2017, sociodemographic and clinical characteristics were collected from 144 patients with tuberculosis at the Hospital Civil de Guadalajara, Mexico. Isolates were subjected to drug-susceptibility testing. Clinical predictors of DR-TB were determined using univariate and multivariate analysis. Any drug, isoniazid, and rifampin resistance rates were 47.7, 23.0, and 11.6%, respectively. The visualization of cavities and nodules through either chest radiography or computed tomography were independent predictors of DR-TB. In conclusion, early detection of DR-TB in this population could be based on multiple cavities being observed using chest imaging. This study's results can be applied to future patients with TB in our community to optimize the DR-TB diagnostic process.

Topics: Adult; Antitubercular Agents; Female; Humans; Isoniazid; Male; Mexico; Middle Aged; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

To measure the association between phenotypic drug resistance and the risk of tuberculosis infection and disease among household contacts of patients with pulmonary tuberculosis.. 106 district health centers in Lima, Peru between September 2009 and September 2012.. Prospective cohort study.. 10 160 household contacts of 3339 index patients with tuberculosis were classified on the basis of the drug resistance profile of the patient: 6189 were exposed to drug susceptible strains of. Tuberculosis infection (positive tuberculin skin test) and the incidence of active disease (diagnosed by positive sputum smear or chest radiograph) after 12 months of follow-up.. Household contacts exposed to patients with multidrug resistant tuberculosis had an 8% (95% confidence interval 4% to 13%) higher risk of infection by the end of follow-up compared with household contacts of patients with drug sensitive tuberculosis. The relative hazard of incident tuberculosis disease did not differ among household contacts exposed to multidrug resistant tuberculosis and those exposed to drug sensitive tuberculosis (adjusted hazard ratio 1.28, 95% confidence interval 0.9 to 1.83).. Household contacts of patients with multidrug resistant tuberculosis were at higher risk of tuberculosis infection than contacts exposed to drug sensitive tuberculosis. The risk of developing tuberculosis disease did not differ among contacts in both groups. The evidence invites guideline producers to take action by targeting drug resistant and drug sensitive tuberculosis, such as early detection and effective treatment of infection and disease.. ClinicalTrials.gov NCT00676754.

Topics: Adolescent; Adult; Aged; Antitubercular Agents; Child; Child, Preschool; Contact Tracing; Disease Progression; Female; Follow-Up Studies; Humans; Incidence; Infant; Infant, Newborn; Isoniazid; Kaplan-Meier Estimate; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Peru; Prospective Studies; Rifampin; Sputum; Tuberculin Test; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

New anti-tuberculosis regimens that are shorter, simpler, and less toxic than those that are currently available are needed as part of the global effort to address the tuberculosis epidemic. We aimed to investigate the bactericidal activity and safety profile of combinations of bedaquiline, pretomanid, moxifloxacin, and pyrazinamide in the first 8 weeks of treatment of pulmonary tuberculosis.. In this multicentre, open-label, partially randomised, phase 2b trial, we prospectively recruited patients with drug-susceptible or rifampicin-resistant pulmonary tuberculosis from seven sites in South Africa, two in Tanzania, and one in Uganda. Patients aged 18 years or older with sputum smear grade 1+ or higher were eligible for enrolment, and a molecular assay (GeneXpert or MTBDRplus) was used to confirm the diagnosis of tuberculosis and to distinguish between drug-susceptible and rifampicin-resistant tuberculosis. Patients who were HIV positive with a baseline CD4 cell count of less than 100 cells per uL were excluded. Patients with drug-susceptible tuberculosis were randomly assigned (1:1:1) using numbered treatment packs with sequential allocation by the pharmacist to receive 56 days of treatment with standard tuberculosis therapy (oral isoniazid, rifampicin, pyrazinamide, and ethambutol; HRZE), or pretomanid (oral 200 mg daily) and pyrazinamide (oral 1500 mg daily) with either oral bedaquiline 400 mg daily on days 1-14 then 200 mg three times per week (B. Between Oct 24, 2014, and Dec 15, 2015, we enrolled 180 patients with drug-susceptible tuberculosis (59 were randomly assigned to B. B. TB Alliance, UK Department for International Development, Bill & Melinda Gates Foundation, US Agency for International Development, Directorate General for International Cooperation of the Netherlands, Irish Aid, Australia Department of Foreign Affairs and Trade, and the Federal Ministry for Education and Research of Germany.

Topics: Antitubercular Agents; Diarylquinolines; Drug Administration Schedule; Drug Therapy, Combination; Humans; Moxifloxacin; Nitroimidazoles; Pyrazinamide; Rifampin; South Africa; Sputum; Tanzania; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Uganda

Linezolid improves the treatment outcomes of multidrug-resistant tuberculosis substantially. We investigated whether use of linezolid instead of ethambutol increases the proportion of sputum culture conversion at 8 weeks of treatment in patients with pulmonary tuberculosis.. We did a phase 2, multicentre, randomised, open-label trial for patients with pulmonary tuberculosis at the three affiliated hospitals to Seoul National University and National Medical Center (Seoul-Seongnam, South Korea). Patients, aged 20-80 years, with a positive sputum for pulmonary tuberculosis, but without resistance to rifampicin, and current treatment administered for 7 days or fewer, were randomly assigned at a 1:1:1 ratio into three groups. The control group received ethambutol (2 months) with isoniazid, rifampicin, and pyrazinamide. The second group used linezolid (600 mg/day) for 2 weeks and the third group for 4 weeks instead of ethambutol for 2 months. We used a minimisation method to randomise, and stratified according to institution, cavitation on chest radiographs, and diabetes. The primary endpoint was the proportion of patients with negative culture conversion of sputum in liquid media after 8 weeks of treatment. The results of this trial were analysed primarily in the modified intention-to-treat population. The trial is registered with ClinicalTrials.gov, number NCT01994460.. Between Feb 19, 2014, and Jan 13, 2017, a total of 429 patients were enrolled and 428 were randomly assigned into either the control group (142 patients), the linezolid 2 weeks group (143 patients), or the linezolid 4 weeks group (143 patients). Among them, 401 were eligible for primary efficacy analyses. In the modified intention-to-treat analyses, negative cultures in liquid media at 8 weeks of treatment were observed in 103 (76·9%) of 134 control patients, 111 (82·2%) of 135 in the linezolid 2 weeks group, and 100 (75·8%) of 132 in the linezolid 4 weeks groups. The difference from the control group was 5.4% (95% CI -4·3 to 15·0, p=0·28) for the linezolid 2 weeks group and -1·1% (-11·3 to 9·1, p=0·83) for the linezolid 4 weeks group. Numbers of patients who experienced at least one adverse event were similar across the groups (86 [62·8%] of 137 in control, 79 [57·2%] of 138 in the linezolid 2 weeks group, and 75 [62·0%] of 121 in the linezolid 4 weeks group). Resistance to linezolid was not identified in any patient.. Higher rates of culture conversion at 8 weeks of treatment with short-term use of linezolid were not observed. However, safety analyses and the resistance profile suggested the potential role of linezolid in shortening of treatment for drug-susceptible tuberculosis.. Ministry of Health and Welfare, South Korea.

Topics: Adult; Aged; Aged, 80 and over; Antitubercular Agents; Drug Substitution; Drug Therapy, Combination; Ethambutol; Female; Humans; Isoniazid; Linezolid; Male; Middle Aged; Prospective Studies; Pyrazinamide; Rifampin; Sputum; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

Delamanid is one of two recently approved drugs for the treatment of multidrug-resistant tuberculosis. We aimed to evaluate the safety and efficacy of delamanid in the first 6 months of treatment.. This randomised, double-blind, placebo-controlled, phase 3 trial was done at 17 sites in seven countries (Estonia, Latvia, Lithuania, Moldova, Peru, the Philippines, and South Africa). We enrolled eligible adults (>18 years) with pulmonary multidrug-resistant tuberculosis to receive, in combination with an optimised background regimen developed according to WHO and national guidelines, either oral delamanid (100 mg twice daily) for 2 months followed by 200 mg once daily for 4 months or placebo (same regimen). Patients were centrally randomised (2:1) and stratified by risk category for delayed sputum culture conversion. Primary outcomes were the time to sputum culture conversion over 6 months and the difference in the distribution of time to sputum culture conversion over 6 months between the two groups, as assessed in the modified intention-to-treat population. The trial is registered at ClinicalTrials.gov, number NCT01424670.. Between Sept 2, 2011, and Nov 27, 2013, we screened 714 patients, of whom 511 were randomly assigned (341 to delamanid plus optimised background regimen [delamanid group] and 170 to placebo plus optimised background regimen [placebo group]) and formed the safety analysis population. 327 patients were culture-positive for multidrug-resistant tuberculosis at baseline and comprised the efficacy analysis population (226 in the delamanid group and 101 in the placebo group). Median time to sputum culture conversion did not differ between the two groups (p=0·0562; modified Peto-Peto), with 51 days (IQR 29-98) in the delamanid group and 57 days (43-85) in the placebo group; the hazard ratio was 1·17 (95% CI 0·91-1·51, p=0·2157). 501 (98·0%) of 511 patients had at least one treatment-emergent adverse event. 136 (26·6%) of 511 patients had at least one serious treatment-emergent adverse event; the incidence was similar between treatment groups (89 [26·1%] of 341 patients for delamanid and 47 [27·6%] of 170 for placebo). Deaths related to treatment-emergent adverse events were similar between groups (15 [4·4%] of 341 for delamanid and six [3·5%] of 170 for placebo). No deaths were considered to be related to delamanid.. The reduction in median time to sputum culture conversion over 6 months was not significant in the primary analysis. Delamanid was well tolerated with a highly characterised safety profile. Further evaluation of delamanid is needed to determine its role in a rapidly evolving standard of care.. Otsuka Pharmaceutical.

Topics: Antitubercular Agents; Double-Blind Method; Drug Administration Schedule; Drug Monitoring; Drug Therapy, Combination; Female; Humans; Isoniazid; Male; Middle Aged; Nitroimidazoles; Oxazoles; Rifampin; Sputum; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Cohort studies in Bangladesh showed promising cure rates among patients with multidrug-resistant tuberculosis who received existing drugs in regimens shorter than that recommended by the World Health Organization (WHO) in 2011.. We conducted a phase 3 noninferiority trial in participants with rifampin-resistant tuberculosis that was susceptible to fluoroquinolones and aminoglycosides. Participants were randomly assigned, in a 2:1 ratio, to receive a short regimen (9 to 11 months) that included high-dose moxifloxacin or a long regimen (20 months) that followed the 2011 WHO guidelines. The primary efficacy outcome was a favorable status at 132 weeks, defined by cultures negative for. Of 424 participants who underwent randomization, 383 were included in the modified intention-to-treat population. Favorable status was reported in 79.8% of participants in the long-regimen group and in 78.8% of those in the short-regimen group - a difference, with adjustment for human immunodeficiency virus status, of 1.0 percentage point (95% confidence interval [CI], -7.5 to 9.5) (P = 0.02 for noninferiority). The results with respect to noninferiority were consistent among the 321 participants in the per-protocol population (adjusted difference, -0.7 percentage points; 95% CI, -10.5 to 9.1). An adverse event of grade 3 or higher occurred in 45.4% of participants in the long-regimen group and in 48.2% in the short-regimen group. Prolongation of either the QT interval or the corrected QT interval (calculated with Fridericia's formula) to 500 msec occurred in 11.0% of participants in the short-regimen group, as compared with 6.4% in the long-regimen group (P = 0.14); because of the greater incidence in the short-regimen group, participants were closely monitored and some received medication adjustments. Death occurred in 8.5% of participants in the short-regimen group and in 6.4% in the long-regimen group, and acquired resistance to fluoroquinolones or aminoglycosides occurred in 3.3% and 2.3%, respectively.. In persons with rifampin-resistant tuberculosis that was susceptible to fluoroquinolones and aminoglycosides, a short regimen was noninferior to a long regimen with respect to the primary efficacy outcome and was similar to the long regimen in terms of safety. (Funded by the U.S. Agency for International Development and others; Current Controlled Trials number, ISRCTN78372190; ClinicalTrials.gov number, NCT02409290.).

Topics: Adult; AIDS-Related Opportunistic Infections; Antitubercular Agents; Drug Administration Schedule; Drug Therapy, Combination; Female; Humans; Intention to Treat Analysis; Kaplan-Meier Estimate; Male; Medication Adherence; Middle Aged; Moxifloxacin; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

We determined the high-resolution allele and haplotype frequencies at the human leucocyte antigen (HLA)A, B and DRB1 loci in the Han population of Hubei province, the TB endemic area of Central China, with pulmonary tuberculosis (PTB), and established the relationship between HLA-A, B and DRB1 alleles as well as haplotypes and susceptibility to multidrug-resistant and rifampicin-resistant tuberculosis (MDR/RR-TB). Blood samples were drawn from 174 patients with MDR/RR-TB and 838 patients with drug-susceptible PTB in ethnic Han population from Hubei province (central China). Four-digit allele genotyping of HLA- A, B and DRB1 loci was performed using polymerase chain reaction with sequence-specific oligonucleotide probes (PCR- SSOP). The allele and haplotype frequencies of HLA-A, B and DRB1 were determined and compared between patients with MDR/RR-TB and patients with drug-susceptible PTB. Statistical analysis of the generated data indicated no departure from expectation of Hardy-Weinberg equilibrium (HWE) at all loci of the control group. Multivariate analysis identified allele DRB1*08:01 (p < .0001; OR = 174.5, 95% CI 15.3-1987.2) as independent predictor of MDR/RR-TB, except for old age (p < .0001; OR = 10. 9, 95% CI 7.6-15.8), previous treatment history (p < .0001; OR = 11.0, 95% CI 7.2-16.7) and poor compliance to treatment (p < .0001; OR = 12.9, 95% CI 8.4-20.0). While in the subgroup of new TB cases, DRB1*08:01 (p < .0001; OR = 80.3, 95% CI 7.0-917.1) and older age (p < .0001; OR = 3.9, 95% CI 2.4-6.4) were independent susceptibility factors for primary MDR/RR-TB. Our results suggest that a combination of clinical and host genetic information about tuberculosis patients may contribute to prediction and early detection of MDR/RR-TB.

Topics: Adolescent; Adult; Aged; Alleles; Asian People; China; Female; Genetic Loci; Genetic Predisposition to Disease; HLA Antigens; Humans; Male; Middle Aged; Polymorphism, Genetic; Rifampin; Tuberculosis, Multidrug-Resistant

The benefit of daily over thrice-weekly antituberculosis therapy among HIV-positive patients with pulmonary tuberculosis (TB) who are receiving antiretroviral therapy remains unproven.. To compare the efficacy and safety of daily, part-daily, and intermittent antituberculosis therapy regimens in the treatment of HIV-associated pulmonary TB.. This open-label, randomized clinical trial was conducted by the National Institute for Research in Tuberculosis, south India. Adults infected with HIV with newly diagnosed, culture-positive, pulmonary TB were enrolled between September 14, 2009, and January 18, 2016.. Patients were randomized to daily, part-daily, and intermittent antituberculosis therapy regimens, stratified by baseline CD4 lymphocyte count and sputum smear grade. Antiretroviral therapy was initiated as per national guidelines. Clinical and sputum microbiological examinations of patients were performed monthly until 18 months after randomization. Adverse events were recorded using standard criteria.. The primary outcome was favorable response, defined as treatment completion with all available sputum cultures negative for Mycobacterium tuberculosis during the last 2 months of treatment. Unfavorable responses included treatment failures, dropouts, deaths, and toxic effects among regimens.. Of 331 patients (251 [76%] male; mean [SD] age, 39 [9] years; mean [SD] HIV viral load, 4.9 [1.2] log10 copies/mL; and median [interquartile range] CD4 lymphocyte count, 138 [69-248] cells/μL), favorable responses were experienced by 91% (89 of 98), 80% (77 of 96), and 77% (75 of 98) in the daily, part-daily, and intermittent regimens, respectively. With the difference in outcome between daily and intermittent regimens crossing the O'Brien-Fleming group sequential boundaries and acquired rifampicin resistance emergence (n = 4) confined to the intermittent group, the data safety monitoring committee halted the study. A total of 18 patients died and 18 patients dropped out during the treatment period in the 3 regimens. Six, 4, and 6 patients in the daily, part-daily, and intermittent regimens, respectively, had TB recurrence.. Among HIV-positive patients with pulmonary TB receiving antiretroviral therapy, a daily anti-TB regimen proved superior to a thrice-weekly regimen in terms of efficacy and emergence of rifampicin resistance.. clinicaltrials.gov Identifier: NCT00933790.

Topics: Adult; Anti-HIV Agents; Antitubercular Agents; CD4 Lymphocyte Count; Directly Observed Therapy; Drug Administration Schedule; Ethambutol; Female; HIV Infections; Humans; Immune Reconstitution Inflammatory Syndrome; Isoniazid; Male; Middle Aged; Patient Dropouts; Proportional Hazards Models; Rifampin; Streptomycin; Treatment Failure; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Viral Load

Resistance to isoniazid is the most common form of drug-resistance in tuberculosis. However only a tiny proportion of TB patients in the world have access to isoniazid drug susceptibility testing-the widely implemented Xpert MTB/RIF technology only tests for resistance to rifampicin. Patients with isoniazid mono resistance that is not identified at baseline are treated with a standard regimen that effectively results in rifampicin mono-therapy during the latter four months of the six month treatment course, exposing remaining viable organisms to a single agent and greatly increasing the risk of development of multi drug-resistant TB. Unusually, Peru has pioneered universal pre-treatment drug susceptibility testing with methods that identify isoniazid resistance and has thus identified a large number of individuals requiring tailored therapy. Since 2010, treatment in Peru for isoniazid-resistant tuberculosis without multidrug-resistant tuberculosis (Hr-TB) has been with a standardized nine-month regimen of levofloxacin, rifampicin, ethambutol and pyrazinamide. The objectives of this study were to evaluate the outcomes of treatment for patients with Hr-TB initiating treatment with this regimen between January 2012 and December 2014 and to determine factors affecting these outcomes.. Retrospective cross-sectional study; case data were obtained from the national registry of drug-resistant tuberculosis. Patients diagnosed with isoniazid resistant TB without resistance to rifampicin, pyrazinamide, ethambutol and quinolones as determined by either a rapid drug susceptibility testing (DST) (nitrate reductase test, MODS, Genotype MTBDRplus) or by the proportion method were included.. A total of 947 cases were evaluated (a further 403 without treatment end date were excluded), with treatment success in 77.2% (731 cases), loss to follow-up in 19.7% (186 cases), treatment failure in 1.2% (12 cases), and death in 1.9% (18 cases). Unfavorable outcomes were associated in multivariate analysis with male gender (OR 0.50, 95% CI 0.34-0.72, p<0.05), lack of rapid DST (OR 0.67, 95% CI 0.50-0.91, p = 0.01), additional use of an injectable second-line anti-tuberculous drug (OR 0.46, 95% CI 0.31-0.70, p<0.05), and treatment initiation in 2014 (OR 0.77, 95% CI 0.62-0.94, p = 0.01).. The treatment regimen implemented in Peru for isoniazid resistant TB is effective for TB cure and is not improved by addition of an injectable second-line agent. Access to rapid DST and treatment adherence need to be strengthened to increase favorable results.

Topics: Adolescent; Adult; Child; Child, Preschool; Cross-Sectional Studies; Drug Therapy, Combination; Ethambutol; Female; Humans; Infant; Infant, Newborn; Isoniazid; Levofloxacin; Male; Middle Aged; Peru; Pyrazinamide; Retrospective Studies; Rifampin; Sex Factors; Time Factors; Tuberculosis, Multidrug-Resistant

We conducted a single-center retrospective cohort study to evaluate whether the HbA1c level on admission could predict the in-hospital treatment outcome of smear-positive non-multi-drug-resistant HIV-negative culture-proven pulmonary tuberculosis inpatients. Our standard regimens under the direct observation were HRZE or HRE for the first two months followed by combination therapy with isoniazid and rifampicin. Our cohort consisted of consecutive 239 patients consisted of 147 men and 92 women with a median age of 73 years. The HbA1c level of patients whose HbA1c was above 7.0% on admission showed clear declining trends after admission. HbA1c on admission had no Spearman's rank correlation with time to discharge alive (r = 0.17) and time to becoming non-infective (r = 0.17). By Kaplan-Meier curves and a log-rank trend test, HbA1c quartile subgroups showed no association with times to discharge alive (p = 0.431), becoming non-infective (p = 0.113), and in-hospital death (p = 0.427). Based on multi-variate Cox analysis, HbA1c on admission had no significant impact on time to discharge alive (hazard ratio = 1.03, 95% CI 0.89-1.20, p = 0.659), becoming non-infective (hazard ratio = 0.93, 95% CI 0.80-1.06, p = 0.277), and in-hospital death (hazard ratio = 0.68, 0.43-1.07, p = 0.097). In conclusion, the HbA1c level on admission did not seem to affect in-hospital tuberculosis treatment outcomes in Japanese cohort.

Topics: Adult; Aged; Aged, 80 and over; Female; Glycated Hemoglobin; HIV; Humans; Isoniazid; Male; Middle Aged; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Point-of-care (POC) diagnostics have the potential to reduce pretreatment loss to follow-up and delays to initiation of appropriate tuberculosis (TB) treatment.. To evaluate the effect of a POC diagnostic strategy on initiation of appropriate TB treatment.. We conducted a cluster-randomized trial of adults with cough who were HIV positive and/or at high risk of drug-resistant TB. Two-week time blocks were randomized to two strategies: (1) Xpert MTB/RIF test (Cepheid, Sunnyvale, CA) performed at a district hospital laboratory or (2) POC Xpert MTB/RIF test performed at a primary health care clinic. All participants provided two sputum specimens: one for the Xpert test and the other for culture as a reference standard. The primary outcome was the proportion of participants with culture-positive pulmonary tuberculosis (PTB) initiated on appropriate TB treatment within 30 days.. Between August 22, 2011, and March 1, 2013, 36 two-week blocks were randomized, and 1,297 individuals were enrolled (646 in the laboratory arm, 651 in the POC arm), 159 (12.4%) of whom had culture-positive PTB. The proportions of participants with culture-positive PTB initiated on appropriate TB treatment within 30 days were 76.5% in the laboratory arm and 79.5% in the POC arm (odds ratio, 1.13; 95% confidence interval, 0.51-2.53; P = 0.76; risk difference, 3.1%; 95% confidence interval, -16.2 to 10.1). The median time to initiation of appropriate treatment was 7 days (laboratory) versus 1 day (POC).. POC positioning of the Xpert test led to more rapid initiation of appropriate TB treatment. Achieving one-stop diagnosis and treatment for all people with TB will require simpler, more sensitive diagnostics and broader strengthening of health systems. Clinical trial registered with www.isrctn.com (ISRCTN 18642314) and www.sanctr.gov.za (DOH-27-0711-3568).

Topics: Adult; Antibiotics, Antitubercular; Female; Humans; Male; Middle Aged; Point-of-Care Systems; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Topics: Antitubercular Agents; Bacterial Load; Bacterial Proteins; Colony Count, Microbial; DNA-Directed RNA Polymerases; Drug Resistance, Bacterial; Gene Expression; Humans; Models, Statistical; Mutation Rate; Mycobacterium tuberculosis; Rifampin; Tissue Distribution; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

In 2012, as a pilot for Botswana's national Xpert MTB/RIF (Xpert) rollout plans, intensified tuberculosis (TB) case finding (ICF) activities were strengthened at 22 HIV treatment clinics prior to phased activation of 13 Xpert instruments. Together, the strengthened ICF intervention and Xpert activation are referred to as the "Xpert package".. The evaluation, called the Xpert Package Rollout Evaluation using a Stepped-wedge design (XPRES), has two key objectives: (1) to compare sensitivity of microscopy-based and Xpert-based pulmonary TB diagnostic algorithms in diagnosing sputum culture-positive TB; and (2) to evaluate impact of the "Xpert package" on all-cause, 6-month, adult antiretroviral therapy (ART) mortality. A pragmatic, stepped-wedge cluster-randomized trial design was chosen. The design involves enrollment of three cohorts: (1) cohort R, a retrospective cohort of all study clinic ART enrollees in the 24 months before study initiation (July 31, 2012); (2) cohort A, a prospective cohort of all consenting patients presenting to study clinics after study initiation, who received the ICF intervention and the microscopy-based TB diagnostic algorithm; and (3) cohort B, a prospective cohort of all consenting patients presenting to study clinics after Xpert activation, who received the ICF intervention and the Xpert-based TB diagnostic algorithm. TB diagnostic sensitivity will be compared between TB culture-positive enrollees in cohorts A and B. All-cause, 6-month ART-mortality will be compared between cohorts R and B. With anticipated cohort R, A, and B sample sizes of about 10,131, 1,878, and 4,258, respectively, the study is estimated to have >80 % power to detect differences in pre-versus post-Xpert TB diagnostic sensitivity if pre-Xpert sensitivity is ≤52.5 % and post-Xpert sensitivity ≥82.5 %, and >80 % power to detect a 40 % reduction in all-cause, 6-month, ART mortality between cohorts R and B if cohort R mortality is ≥13/100 person-years.. Only one small previous trial (N = 424) among ART enrolees in Zimbabwe evaluated, in a secondary analysis, Xpert impact on all-cause 6-month ART mortality. No mortality impact was observed. This Botswana trial, with its larger sample size and powered specifically to detect differences in all-cause 6-month ART mortality, remains well-positioned to contribute understanding of Xpert impact.. Retrospectively registered at ClinicalTrials.gov: NCT02538952 .

Topics: Adult; Ambulatory Care Facilities; Anti-HIV Agents; Botswana; Humans; Microscopy; Mycobacterium tuberculosis; Prospective Studies; Radiography, Thoracic; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

New antituberculosis regimens are urgently needed to shorten tuberculosis treatment. Following on from favourable assessment in a 2 week study, we investigated a novel regimen for efficacy and safety in drug-susceptible and multidrug-resistant (MDR) tuberculosis during the first 8 weeks of treatment.. We did this phase 2b study of bactericidal activity--defined as the decrease in colony forming units (CFUs) of Mycobacterium tuberculosis in the sputum of patients with microscopy smear-positive pulmonary tuberculosis-at eight sites in South Africa and Tanzania. We enrolled treatment-naive patients with drug-susceptible, pulmonary tuberculosis, who were randomly assigned by computer-generated sequences to receive either 8 weeks of moxifloxacin, 100 mg pretomanid (formerly known as PA-824), and pyrazinamide (MPa100Z regimen); moxifloxacin, 200 mg pretomanid, and pyrazinamide (MPa200Z regimen); or the current standard care for drug-susceptible pulmonary tuberculosis, isoniazid, rifampicin, PZA, and ethambutol (HRZE regimen). A group of patients with MDR tuberculosis received MPa200Z (DRMPa200Z group). The primary outcome was bactericidal activity measured by the mean daily rate of reduction in M tuberculosis CFUs per mL overnight sputum collected once a week, with joint Bayesian non-linear mixed-effects regression modelling. We also assessed safety and tolerability by monitoring adverse events. This study is registered with ClinicalTrials.gov, number NCT01498419.. Between March 24, 2012, and July 26, 2013 we enrolled 207 patients and randomly assigned them to treatment groups; we assigned 60 patients to the MPa100Z regimen, 62 to the MPa200Z regimen, and 59 to the HRZE regimen. We non-randomly assigned 26 patients with drug-resistant tuberculosis to the DRMPa200Z regimen. In patients with drug-susceptible tuberculosis, the bactericidal activity of MPa200Z (n=54) on days 0-56 (0·155, 95% Bayesian credibility interval 0·133-0·178) was significantly greater than for HRZE (n=54, 0·112, 0·093-0·131). DRMPa200Z (n=9) had bactericidal activity of 0·117 (0·070-0·174). The bactericidal activity on days 7-14 was strongly associated with bactericidal activity on days 7-56. Frequencies of adverse events were similar to standard treatment in all groups. The most common adverse event was hyperuricaemia in 59 (29%) patients (17 [28%] patients in MPa100Z group, 17 [27%] patients in MPa200Z group, 17 [29%] patients. in HRZE group, and 8 [31%] patients in DRMPa200Z group). Other common adverse events were nausea in (14 [23%] patients in MPa100Z group, 8 [13%] patients in MPa200Z group, 7 [12%] patients in HRZE group, and 8 [31%] patients in DRMPa200Z group) and vomiting (7 [12%] patients in MPa100Z group, 7 [11%] patients in MPa200Z group, 7 [12%] patients in HRZE group, and 4 [15%] patients in DRMPa200Z group). No on-treatment electrocardiogram occurrences of corrected QT interval more than 500 ms (an indicator of potential of ventricular tachyarrhythmia) were reported. No phenotypic resistance developed to any of the drugs in the regimen.. The combination of moxifloxacin, pretomanid, and pyrazinamide, was safe, well tolerated, and showed superior bactericidal activity in drug-susceptible tuberculosis during 8 weeks of treatment. Results were consistent between drug-susceptible and MDR tuberculosis. This new regimen is ready to enter phase 3 trials in patients with drug-susceptible tuberculosis and MDR-tuberculosis, with the goal of shortening and simplifying treatment.. Global Alliance for TB Drug Development.

Topics: Adolescent; Adult; Antitubercular Agents; Colony Count, Microbial; Drug Therapy, Combination; Ethambutol; Female; Fluoroquinolones; Humans; Isoniazid; Male; Moxifloxacin; Nitroimidazoles; Pyrazinamide; Rifampin; South Africa; Sputum; Tanzania; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

In South Africa, sputum smear microscopy has been replaced with Xpert MTB/RIF as the initial diagnostic test for tuberculosis. In a pragmatic parallel cluster-randomised trial, we evaluated the effect on patient and programme outcomes.. We randomly allocated 20 laboratories (clusters) in medium-burden districts of South Africa to either an Xpert (immediate Xpert) or microscopy (Xpert deferred) group (1:1), stratified by province. At two primary care clinics per laboratory, a systematic sample of adults giving sputum for tuberculosis investigation was assessed for eligibility. The primary outcome was mortality at 6 months from enrolment. Masking of participants' group allocation was not possible because of the pragmatic trial design. The trial is registered with the ISRCTN registry (ISRCTN68905568) and the South African Clinical Trial Register (DOH-27-1011-3849).. Between June and November, 2012, 4972 people were screened, and 4656 (93·6%) enrolled (median age 36 years; 2891 [62%] female; 2212 [62%] reported being HIV-positive). There was no difference between the Xpert and microscopy groups with respect to mortality at 6 months (91/2324 [3·9%] vs 116/2332 [5·0%], respectively; adjusted risk ratio [aRR] 1·10, 95% CI 0·75-1·62]).. Xpert did not reduce mortality at 6 months compared with sputum microscopy. Improving outcomes in drug-sensitive tuberculosis programmes might require not only better diagnostic tests but also better linkage to care.. Bill & Melinda Gates Foundation.

Topics: Adult; Analysis of Variance; Antitubercular Agents; Comorbidity; Drug Resistance, Bacterial; Endpoint Determination; Female; HIV Infections; Humans; Male; Middle Aged; Molecular Diagnostic Techniques; Mortality; Outcome and Process Assessment, Health Care; Rifampin; South Africa; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Study C was an open-label, non-inferiority, randomised controlled trial of fixed-dose combination (FDC) or separate drugs given during the intensive phase of treatment to 1585 patients with smear-positive pulmonary tuberculosis conducted at 11 sites in Africa, Asia and Latin America. Thirty months post-randomisation, the failure/relapse rates in the per protocol population were 7.4% of 591 patients on FDCs and 6.5% of 587 patients on separate drugs; the site-adjusted difference was 0.3% (90%CI -1.8 to 2.3). In the modified intention-to-treat analysis, the corresponding results were respectively 17.9% of 683 and 16.1% of 671; the site-adjusted difference was 2.0% (90%CI -1.2 to 5.2).

Topics: Africa; Antitubercular Agents; Asia; Dose-Response Relationship, Drug; Drug Combinations; Ethambutol; Female; Follow-Up Studies; Humans; Isoniazid; Latin America; Male; Pyrazinamide; Recurrence; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Xpert MTB/RIF is approved for use in tuberculosis (TB) and rifampicin-resistance diagnosis. However, data are limited on the impact of Xpert under routine conditions in settings with high TB burden.. A pragmatic prospective cluster-randomised trial of Xpert for all individuals with presumptive (symptomatic) TB compared to the routine diagnostic algorithm of sputum microscopy and limited use of culture was conducted in a large TB/HIV primary care clinic. The primary outcome was the proportion of bacteriologically confirmed TB cases not initiating TB treatment by 3 mo after presentation. Secondary outcomes included time to TB treatment and mortality. Unblinded randomisation occurred on a weekly basis. Xpert and smear microscopy were performed on site. Analysis was both by intention to treat (ITT) and per protocol. Between 7 September 2010 and 28 October 2011, 1,985 participants were assigned to the Xpert (n = 982) and routine (n = 1,003) diagnostic algorithms (ITT analysis); 882 received Xpert and 1,063 routine (per protocol analysis). 13% (32/257) of individuals with bacteriologically confirmed TB (smear, culture, or Xpert) did not initiate treatment by 3 mo after presentation in the Xpert arm, compared to 25% (41/167) in the routine arm (ITT analysis, risk ratio 0.51, 95% CI 0.33-0.77, p = 0.0052). The yield of bacteriologically confirmed TB cases among patients with presumptive TB was 17% (167/1,003) with routine diagnosis and 26% (257/982) with Xpert diagnosis (ITT analysis, risk ratio 1.57, 95% CI 1.32-1.87, p<0.001). This difference in diagnosis rates resulted in a higher rate of treatment initiation in the Xpert arm: 23% (229/1,003) and 28% (277/982) in the routine and Xpert arms, respectively (ITT analysis, risk ratio 1.24, 95% CI 1.06-1.44, p = 0.013). Time to treatment initiation was improved overall (ITT analysis, hazard ratio 0.76, 95% CI 0.63-0.92, p = 0.005) and among HIV-infected participants (ITT analysis, hazard ratio 0.67, 95% CI 0.53-0.85, p = 0.001). There was no difference in 6-mo mortality with Xpert versus routine diagnosis. Study limitations included incorrect intervention allocation for a high proportion of participants and that the study was conducted in a single clinic.. These data suggest that in this routine primary care setting, use of Xpert to diagnose TB increased the number of individuals with bacteriologically confirmed TB who were treated by 3 mo and reduced time to treatment initiation, particularly among HIV-infected participants.. Pan African Clinical Trials Registry PACTR201010000255244. Please see later in the article for the Editors' Summary.

Topics: Adolescent; Adult; Aged; Ambulatory Care Facilities; Antibiotics, Antitubercular; Drug Resistance, Bacterial; Female; HIV Infections; Humans; Male; Middle Aged; Mycobacterium tuberculosis; Prevalence; Primary Health Care; Prospective Studies; Real-Time Polymerase Chain Reaction; Rifampin; South Africa; Time-to-Treatment; Tuberculosis; Tuberculosis, Multidrug-Resistant; Young Adult

Abundant evidence on Xpert MTB/RIF accuracy for diagnosing tuberculosis (TB) and rifampicin resistance has been produced, yet there are few data on the population benefit of its programmatic use. We assessed whether the implementation of Xpert MTB/RIF in routine conditions would (1) increase the notification rate of laboratory-confirmed pulmonary TB to the national notification system and (2) reduce the time to TB treatment initiation (primary endpoints).. We conducted a stepped-wedge cluster-randomized trial from 4 February to 4 October 2012 in 14 primary care laboratories in two Brazilian cities. Diagnostic specimens were included for 11,705 baseline (smear microscopy) and 12,522 intervention (Xpert MTB/RIF) patients presumed to have TB. Single-sputum-sample Xpert MTB/RIF replaced two-sputum-sample smear microscopy for routine diagnosis of pulmonary TB. In total, 1,137 (9.7%) tests in the baseline arm and 1,777 (14.2%) in the intervention arm were positive (p<0.001), resulting in an increased bacteriologically confirmed notification rate of 59% (95% CI = 31%, 88%). However, the overall notification rate did not increase (15%, 95% CI =  -6%, 37%), and we observed no change in the notification rate for those without a test result (-3%, 95% CI = -37%, 30%). Median time to treatment decreased from 11.4 d (interquartile range [IQR] = 8.5-14.5) to 8.1 d (IQR = 5.4-9.3) (p = 0.04), although not among confirmed cases (median 7.5 [IQR = 4.9-10.0] versus 7.3 [IQR = 3.4-9.0], p = 0.51). Prevalence of rifampicin resistance detected by Xpert was 3.3% (95% CI = 2.4%, 4.3%) among new patients and 7.4% (95% CI = 4.3%, 11.7%) among retreatment patients, with a 98% (95% CI = 87%, 99%) positive predictive value compared to phenotypic drug susceptibility testing. Missing data in the information systems may have biased our primary endpoints. However, sensitivity analyses assessing the effects of missing data did not affect our results.. Replacing smear microscopy with Xpert MTB/RIF in Brazil increased confirmation of pulmonary TB. An additional benefit was the accurate detection of rifampicin resistance. However, no increase on overall notification rates was observed, possibly because of high rates of empirical TB treatment.. ClinicalTrials.gov NCT01363765. Please see later in the article for the Editors' Summary.

Topics: Adolescent; Adult; Antibiotics, Antitubercular; Brazil; Female; Humans; Male; Middle Aged; Molecular Diagnostic Techniques; Polymerase Chain Reaction; Rifampin; Sensitivity and Specificity; Tuberculosis; Tuberculosis, Multidrug-Resistant; Young Adult

HIV-associated tuberculous meningitis (TBM) has high mortality. Aside from the devastating impact of multidrug resistance (MDR) on survival, little is understood about the influence of other bacterial factors on outcome. This study examined the influence of Mycobacterium tuberculosis drug resistance, bacterial lineage, and host vaccination status on outcome in patients with HIV-associated TBM. Mycobacterium tuberculosis isolates from the cerebrospinal fluid of 186 patients enrolled in two studies of HIV-associated TBM in Ho Chi Minh City, Vietnam, were tested for resistance to first-line antituberculosis drugs. Lineage genotyping was available for 122 patients. The influence of antituberculosis drug resistance and M. tuberculosis lineage on 9-month mortality was analyzed using Kaplan-Meier survival analysis and Cox multiple regression models. Isoniazid (INH) resistance without rifampin resistance was associated with increased mortality (adjusted hazard ratio [HR], 1.78, 95% confidence interval [CI], 1.18 to 2.66; P = 0.005), and multidrug resistance was uniformly fatal (n = 8/8; adjusted HR, 5.21, 95% CI, 2.38 to 11.42; P < 0.0001). The hazard ratio for INH-resistant cases was greatest during the continuation phase of treatment (after 3 months; HR, 5.05 [95% CI, 2.23 to 11.44]; P = 0.0001). Among drug-susceptible cases, patients infected with the "modern" Beijing lineage strains had lower mortality than patients infected with the "ancient" Indo-Oceanic lineage (HR, 0.29 [95% CI, 0.14 to 0.61]; P = 0.001). Isoniazid resistance, multidrug resistance, and M. tuberculosis lineage are important determinants of mortality in patients with HIV-associated TBM. Interventions which target these factors may help reduce the unacceptably high mortality in patients with TBM.

Topics: Adult; Antitubercular Agents; Female; Genotype; HIV Infections; Humans; Isoniazid; Male; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Meningeal; Tuberculosis, Multidrug-Resistant; Young Adult

Damien Foundation tuberculosis (TB) control projects in Bangladesh.. To assess the effectiveness of extending the intensive phase (P1) of treatment by 1 month for patients who are smear-positive after 2 months of a 6-month regimen containing rifampicin (RMP) throughout.. Prospective operational study randomising P1 extension for new smear-positive cases with any number of acid-fast bacilli in the 2-month smear (2M+). Smear-defined failures and relapses underwent culture and drug susceptibility testing in addition to DNA sequencing of the rpoB gene before and after treatment.. Of 16,708 patients evaluated, 12,967 were smear-negative at 2 months (2M-); 1871 and 1870 2M+ were randomised to no extension or extension. Respectively 0.3% (95%CI 0.2-0.4), 1.2% (95%CI 0.7-1.8) and 2.0% (95%CI 1.4-2.8) smear- and culture-positive failures, and 1.2% (95%CI 1.0-1.4), 2.6% (95%CI 1.9-3.4) and 0.9% (95%CI 0.5-1.4) relapses were detected. Extension significantly reversed the relative risk (RR) of relapse of 2M+ vs. 2M- patients from 2.2 (95%CI 1.6-3.0) to 0.7 (95%CI 0.4-1.2). The RR for failure remained high, at 7.3 (95%CI 4.7-11.5) with and 4.2 (95%CI 2.5-7.2) without extension. More multi-drug resistance was found after extension, but acquired RMP resistance was similar in all arms. The fair sensitivity of the 2-month smear for failure or relapse (40%) was offset by a very low positive predictive value (3%).. Extension of P1 is very inefficient with this 6-month regimen. Operational research should define appropriate algorithms allowing an earlier switch to the next higher regimen for those in need, using follow-up smears for screening.

Topics: Antitubercular Agents; Bangladesh; Drug Administration Schedule; Humans; Microbial Sensitivity Tests; Predictive Value of Tests; Prospective Studies; Rifampin; Secondary Prevention; Sensitivity and Specificity; Sequence Analysis, DNA; Sputum; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Treatment of latent tuberculosis in patients infected with the human immunodeficiency virus (HIV) is efficacious, but few patients around the world receive such treatment. We evaluated three new regimens for latent tuberculosis that may be more potent and durable than standard isoniazid treatment.. We randomly assigned South African adults with HIV infection and a positive tuberculin skin test who were not taking antiretroviral therapy to receive rifapentine (900 mg) plus isoniazid (900 mg) weekly for 12 weeks, rifampin (600 mg) plus isoniazid (900 mg) twice weekly for 12 weeks, isoniazid (300 mg) daily for up to 6 years (continuous isoniazid), or isoniazid (300 mg) daily for 6 months (control group). The primary end point was tuberculosis-free survival.. The 1148 patients had a median age of 30 years and a median CD4 cell count of 484 per cubic millimeter. Incidence rates of active tuberculosis or death were 3.1 per 100 person-years in the rifapentine-isoniazid group, 2.9 per 100 person-years in the rifampin-isoniazid group, and 2.7 per 100 person-years in the continuous-isoniazid group, as compared with 3.6 per 100 person-years in the control group (P>0.05 for all comparisons). Serious adverse reactions were more common in the continuous-isoniazid group (18.4 per 100 person-years) than in the other treatment groups (8.7 to 15.4 per 100 person-years). Two of 58 isolates of Mycobacterium tuberculosis (3.4%) were found to have multidrug resistance.. On the basis of the expected rates of tuberculosis in this population of HIV-infected adults, all secondary prophylactic regimens were effective. Neither a 3-month course of intermittent rifapentine or rifampin with isoniazid nor continuous isoniazid was superior to 6 months of isoniazid. (Funded by the National Institute of Allergy and Infectious Diseases and others; ClinicalTrials.gov number, NCT00057122.).

Topics: Adult; AIDS-Related Opportunistic Infections; Anti-Retroviral Agents; Antitubercular Agents; Cause of Death; Drug Administration Schedule; Drug Resistance, Bacterial; Drug Therapy, Combination; Female; Follow-Up Studies; HIV Infections; Humans; Isoniazid; Kaplan-Meier Estimate; Male; Mycobacterium tuberculosis; Patient Compliance; Proportional Hazards Models; Rifampin; Risk; Tuberculosis; Tuberculosis, Multidrug-Resistant

The World Health Organization has endorsed the Xpert MTB/RIF assay for investigation of patients suspected of having tuberculosis (TB). However, its utility for routine TB screening and detection of rifampicin resistance among HIV-infected patients with advanced immunodeficiency enrolling in antiretroviral therapy (ART) services is unknown.. Consecutive adult HIV-infected patients with no current TB diagnosis enrolling in an ART clinic in a South African township were recruited regardless of symptoms. They were clinically characterised and invited to provide two sputum samples at a single visit. The accuracy of the Xpert MTB/RIF assay for diagnosing TB and drug resistance was assessed in comparison with other tests, including fluorescence smear microscopy and automated liquid culture (gold standard) and drug susceptibility testing. Of 515 patients enrolled, 468 patients (median CD4 cell count, 171 cells/µl; interquartile range, 102-236) produced at least one sputum sample, yielding complete sets of results from 839 samples. Mycobacterium tuberculosis was cultured from 81 patients (TB prevalence, 17.3%). The overall sensitivity of the Xpert MTB/RIF assay for culture-positive TB was 73.3% (specificity, 99.2%) compared to 28.0% (specificity, 100%) using smear microscopy. All smear-positive, culture-positive disease was detected by Xpert MTB/RIF from a single sample (sensitivity, 100%), whereas the sensitivity for smear-negative, culture-positive TB was 43.4% from one sputum sample and 62.3% from two samples. Xpert correctly identified rifampicin resistance in all four cases of multidrug-resistant TB but incorrectly identified resistance in three other patients whose disease was confirmed to be drug sensitive by gene sequencing (specificity, 94.1%; positive predictive value, 57%).. In this population of individuals at high risk of TB, intensive screening using the Xpert MTB/RIF assay increased case detection by 45% compared with smear microscopy, strongly supporting replacement of microscopy for this indication. However, despite the ability of the assay to rapidly detect rifampicin-resistant disease, the specificity for drug-resistant TB was sub-optimal.

Topics: Adult; Algorithms; Antiretroviral Therapy, Highly Active; Diagnostic Techniques and Procedures; Drug Resistance, Bacterial; Female; HIV Infections; Humans; Male; Mass Screening; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Prevalence; Prospective Studies; Rifampin; Risk Factors; South Africa; Time Factors; Tuberculosis, Multidrug-Resistant

Global control of tuberculosis is hampered by slow, insensitive diagnostic methods, particularly for the detection of drug-resistant forms and in patients with human immunodeficiency virus infection. Early detection is essential to reduce the death rate and interrupt transmission, but the complexity and infrastructure needs of sensitive methods limit their accessibility and effect.. We assessed the performance of Xpert MTB/RIF, an automated molecular test for Mycobacterium tuberculosis (MTB) and resistance to rifampin (RIF), with fully integrated sample processing in 1730 patients with suspected drug-sensitive or multidrug-resistant pulmonary tuberculosis. Eligible patients in Peru, Azerbaijan, South Africa, and India provided three sputum specimens each. Two specimens were processed with N-acetyl-L-cysteine and sodium hydroxide before microscopy, solid and liquid culture, and the MTB/RIF test, and one specimen was used for direct testing with microscopy and the MTB/RIF test.. Among culture-positive patients, a single, direct MTB/RIF test identified 551 of 561 patients with smear-positive tuberculosis (98.2%) and 124 of 171 with smear-negative tuberculosis (72.5%). The test was specific in 604 of 609 patients without tuberculosis (99.2%). Among patients with smear-negative, culture-positive tuberculosis, the addition of a second MTB/RIF test increased sensitivity by 12.6 percentage points and a third by 5.1 percentage points, to a total of 90.2%. As compared with phenotypic drug-susceptibility testing, MTB/RIF testing correctly identified 200 of 205 patients (97.6%) with rifampin-resistant bacteria and 504 of 514 (98.1%) with rifampin-sensitive bacteria. Sequencing resolved all but two cases in favor of the MTB/RIF assay.. The MTB/RIF test provided sensitive detection of tuberculosis and rifampin resistance directly from untreated sputum in less than 2 hours with minimal hands-on time. (Funded by the Foundation for Innovative New Diagnostics.)

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antitubercular Agents; Bacterial Proteins; DNA-Directed RNA Polymerases; Drug Resistance, Bacterial; Female; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Polymerase Chain Reaction; Prospective Studies; Reference Standards; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis; Tuberculosis, Multidrug-Resistant; Young Adult

To evaluate the efficacy and safety of short-term treatment including fluoroquinolones anti-tuberculosis drugs for rifampicin resistant pulmonary tuberculosis (TB) in those areas carrying out the 'TB control project'.. TB cases involved in this study were from TB drug resistance surveillance in Heilongjiang province, Zhejiang province and Shenzhen city from 2004 to 2006. TB cases with rifampicin resistant were randomly divided into the treatment group (including fluoroquinolones anti-tuberculosis drugs group) and the control group (re-treatment regimen group). The treatment group was treated with 3RFT AM Ofx Pto PAS-INH/5RFT Ofx Pto PAS-INH while the control group was treated with 3 H3R3Z3E3S3/5 H3R3E3. Efficacy of short-term treatment was analyzed by per-protocol analysis (PP analysis) and intention-to-treat analysis (ITT analysis) while drug adverse reactions was also observed.. (1) 154 patients with rifampicin resistant pulmonary tuberculosis were recruited among them, 25 (16.2%) were only resistant to rifampicin, 114 (74.0%) to MDR-TB and 15 (9.8%) to others (resistant R+S, resistant R+E and resistant R+E+S). 114 TB cases completed the full course of treatment,with 71 in the treatment group and 43 in the control group. (2) Sputum negative conversion rate of the treatment group and the control group were 78.9% and 65.1% (chi2CMH = 4.558, P = 0.011) respectively, by per-protocol analysis. Sputum negative conversion rate of the treatment group and the control group were 65.9% and 40.6% (chi2CMH = 0.272, P = 0.001) respectively, by intention-to-treat analysis. The sputum negative conversion rate of the treatment group was higher than in the control group when treating rifampicin resistant pulmonary tuberculosis and MDR-TB patients. (3) Three patients withdrew in each of the two groups because of adverse effects to the drugs. Rates of adverse reaction to drugs appeared to be 23.9% (17/71) and 18.6% (8/43) in the treatment and in the control groups, with no statistically significant difference between the two groups.. The efficacy of treatment including fluoroquinolones anti-tuberculosis drugs group seemed better than the re-treatment regimen group in treating patients with rifampicin resistant pulmonary tuberculosis and those MDR-TB patients.

Topics: Adult; Aged; Antitubercular Agents; China; Drug Resistance, Multiple, Bacterial; Drug Therapy, Combination; Female; Fluoroquinolones; Humans; Male; Middle Aged; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

To search for an ideal therapeutic regimen for multidrug resistant tuberculosis conforming to the situation of China.. One hundred and fifty-four patients with rifampin-resistant tuberculosis, 114 multi-drug resistant (MDR-TB) and 40 resistant to other drugs, in Heilongjiang, Zhejiang, and Shenzhen, 107 males and 47 females, aged 39 (19-77), were randomly divided into 2 groups: 85 patients in the group of drug-resistant regimen, 3RFT AM Ofx Pto PAS-INH/5RFT Ofx Pto PAS-INH regimen, including rifapentine (RFT), amikacin (Am), ofloxacin (Ofx), protionamide (Pto), para-aminosalicylic acid-isoniazid (PAS-INH) for 3 months and then RFT, Ofx, Pto, and PAS-INH for 5 months, and 69 in the retreatment regimen group undergoing 3 H3R3Z3E3S3/5 H3R3E3, including isoniazid (H), rifampin (R), pyrazinamide (Z), ethambutol (E), and streptomycin (S) for 3 months and then H, R, and E for 5 months. Sputum smear was checked and the sputum smear conversion rate was calculated as an effective treatment indicator 3, 6, and 8 months later.. One hundred and fourteen of the 154 patients were treated for a good 8 months. The sputum smear conversion rate 8 months after treatment of the drug-resistant regimen group was 65.9% (56/85), significantly higher than that of the retreatment regimen group [40.6% (28/69), chi2 = 9.834, P = 0.002]. Eighty-five of the 114 MDR-TB patients had been treated for a good 8 months with a sputum smear conversion rate of 61.8% (42/68), significantly higher than that of the retreatment regimen group [39.1% (18/46), chi2 = 5.638, P = 0.018]. Sputum smear conversion at the end of the 8th month was related to age, course of disease, therapeutic regimen, and the type of drug-resistance (all P < 0.05). The side-effect rate of the drug-resistant regimen group was 23.9% (17/71), higher than that of the retreatment regimen group [18.6% (8/43)], but not significantly (chi2 = 0.446, P = 0.504).. The drug-resistant regimen recommended above is more effective than the retreatment regimen and should be considered in the areas where the WHO guideline fails to be followed or drug sensitivity test (DST) cannot be conducted and adjusted according to the results of DST and treatment.

Topics: Adult; Aged; Antitubercular Agents; China; Drug Resistance, Bacterial; Drug Therapy, Combination; Female; Humans; Male; Middle Aged; Rifampin; Tuberculosis, Multidrug-Resistant

Patients with multidrug-resistant (MDR) tuberculosis (TB) are at high risk of treatment failure. It is anticipated that early identification of MDR-TB and appropriate treatment will improve patient outcome and disease control. We evaluated the rapid detection of rifampicin resistance in previously treated TB patients, directly from acidfast bacilli (AFB)-positive sputum using a phage-based test, FASTPlaque-Response (Biotec Laboratories Ltd, Ipswich, UK). The ability of rifampicin resistance to predict MDR-TB was also determined.. A prospective study was done comparing performance of the rapid phage test with conventional culture and drug susceptibility testing (DST) in AFB-positive TB patients.. Five primary health clinics and one TB referral centre in the Port Elizabeth Metropolitan area, Eastern Cape.. Sensitivity, specificity and overall accuracy of the phage test were determined compared with gold standard culture and DST. Discrepant results were resolved by molecular detection of mutations conferring rifampicin resistance. The proportion of rifampicin-resistant strains that were MDR was also determined.. Previously treated patients were at a high risk of MDRTB (35.7%). Sensitivity, specificity and overall accuracy of FASTPlaque-Response for rifampicin resistance determination were 95.4% (95% confidence interval (CI): 91.0 - 99.8%), 97.2% (95% CI: 94.5 - 99.9%) and 96.5% (95% CI: 94.1 - 98.9%) respectively compared with conventional DST (unresolved), calculated for specimens that had both FASTPlaque-Response and conventional DST results available. FASTPlaque-Response results were available in 2 days instead of 28 - 85 days with conventional DST. However, only 70.6% of FASTPlaque-Response results were interpretable compared with 86.3% of conventional DST results. The majority (95.5%) of rifampicinresistant strains were MDR-TB.. Rapid detection of rifampicin resistance using FASTPlaque-Response could contribute to improved management of patients at risk of MDR-TB, such as previously treated patients. However, improvement in control of specimen-related contamination is needed to ensure that a higher proportion of FASTPlaque-Response results are interpretable. Where indicated, early modification of therapy could improve patient prognosis and reduce disease transmission.

Topics: Antibiotics, Antitubercular; Bacteriophage Typing; Drug Resistance, Bacterial; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Predictive Value of Tests; Retreatment; Rifampin; South Africa; Sputum; Tuberculosis, Multidrug-Resistant

To evaluate the curative effect and safety of a long course regimen containing Chinese-made rifabutin as compared to the regimen containing rifapentine in the treatment of multi-drug resistant pulmonary tuberculosis.. During 18 month treatment, 130 patients with multi-drug resistant pulmonary tuberculosis were divided into a treatment group (rifabutin, pasiniazide, levofloxacin, ethambutol, ethionamide, amikacin for 3 months, rifabutin, pasiniazide, levofloxacin, ethambutol, ethionamide for 6 months, rifabutin, pasiniazide, levofloxacin, ethambutol for 9 months), and a control group (rifapentine, pasiniazide, levofloxacin, ethambutol, ethionamide, amikacin for 3 months, rifabutin, pasiniazide, levofloxacin, ethambutol, ethionamide for 6 months, rifabutin, pasiniazide, levofloxacin, ethambutol for 9 months) with proportion 1:1 random, and parallel compared method.. After intensive phase, the sputum negative conversion rates (smear negative, culture negative) of the treatment group and the control group were 41.54% (27/65) and 35.94% (23/65), chi(2) = 2.42, P > 0.05, respectively. The remarkable effective rates in chest X-ray of the two groups were all 10.77% (7/65), chi(2) = 0.01, P > 0.05, and the effective rates were 67.69% (44/65) and 56.92% (37/65), chi(2) = 1.44, P > 0.05, respectively. At the end of the treatment, the sputum negative conversion rate (smear negative, culture negative) of the treatment group was 75.0% (48/65), and of the control group was 65.08% (41/65), chi(2) = 1.88, P > 0.05. The remarkable effective rates in chest X-ray of the two groups were 46.15% (30/65) and 44.62% (29/65), chi(2) = 0.02, P > 0.05, and the effective rates were 76.92% (50/65) and 73.85% (48/65), chi(2) = 0.19, P > 0.05, respectively. The cavity closure rates were 23.64% (13/55) and 33.33% (17/51), chi(2) = 0.00, P > 0.05, respectively.. Regimens containing rifabutin or rifapentine. are very effective in sputum negative conversion rate, lesion absorption and cavity closing for the treatment of multi-drug resistant pulmonary tuberculosis, with good safety and tolerance.

Topics: Adult; Antitubercular Agents; Drug Therapy, Combination; Female; Humans; Male; Middle Aged; Rifabutin; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

The incidence of tuberculosis has been increasing substantially on a worldwide basis over the past decade, but no tuberculosis-specific drugs have been discovered in 40 years. We identified a diarylquinoline, R207910, that potently inhibits both drug-sensitive and drug-resistant Mycobacterium tuberculosis in vitro (minimum inhibitory concentration 0.06 mug/ml). In mice, R207910 exceeded the bactericidal activities of isoniazid and rifampin by at least 1 log unit. Substitution of drugs included in the World Health Organization's first-line tuberculosis treatment regimen (rifampin, isoniazid, and pyrazinamide) with R207910 accelerated bactericidal activity, leading to complete culture conversion after 2 months of treatment in some combinations. A single dose of R207910 inhibited mycobacterial growth for 1 week. Plasma levels associated with efficacy in mice were well tolerated in healthy human volunteers. Mutants selected in vitro suggest that the drug targets the proton pump of adenosine triphosphate (ATP) synthase.

Topics: Amino Acid Sequence; Animals; Antitubercular Agents; Bacterial Proton-Translocating ATPases; Diarylquinolines; Dose-Response Relationship, Drug; Drug Evaluation, Preclinical; Drug Resistance, Bacterial; Drug Therapy, Combination; Enzyme Inhibitors; Humans; Male; Mice; Microbial Sensitivity Tests; Molecular Sequence Data; Mycobacterium smegmatis; Mycobacterium tuberculosis; Point Mutation; Protein Subunits; Quinolines; Tuberculosis; Tuberculosis, Multidrug-Resistant

Forty-nine adolescents with active pulmonary tuberculosis were followed up to assess the biological chip test for the detection of rifampicin resistance in Mycobacterium tuberculosis (MBT). Rifampicin resistance (rpo B gene mutation) was detected in 22 (44.9%) patients. Disseminated processes were detected in a larger proportion of the patients with rifampicin resistance than in those with MBT susceptibility (63.6 and 40.7%, respectively (p < 0.05). Comparison of the data on MBT resistance and susceptibility, which had been obtained by bacteriological studies (nutrient medium cultuvations) and the biological chip test, revealed their agreement in 50% of the cases. A response could be showed after 2-3 months in the former case and after 2-3 days in the latter case. With the biological chip test, the resistance of MBT to rifampicin was additionally established in 38.7% of the patients with negative cultivation tests on admission and during therapy. Follow-ups have demonstrated that MBT resistance to rifampicin preserves longer with the biological microchip test than that with nutrient medium cultivation.

Topics: Adolescent; Antitubercular Agents; Drug Resistance, Bacterial; Humans; Lab-On-A-Chip Devices; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Several therapeutic regimens for drug-resistant tuberculosis have been suggested, most of them with a total duration of 18-24 months.. To report our experience using a shorter regimen.. Fifty patients with drug-resistant pulmonary tuberculosis were managed by withdrawing all anti-tuberculosis drugs until the results of a drug sensitivity test were obtained (approximately 3 months), and then a 12-month self-administered regimen with four to six anti-tuberculosis drugs at full daily doses was initiated, based primarily on the sensitivity test and secondarily on the history of previous treatment.. In 31 patients treatment was completed as planned, in six it was irregular and 13 definitively abandoned it. In the best scenario, 90.3% (28/31) of patients with full treatment were cured; this outcome was similar for both multidrug-resistant (MDR, n = 18, 88.9%) and non-MDR (n = 13, 92.3%) patients. Six months later, the relapse rate was 4.8%, and after a 5-year follow-up 14 out of 18 cured patients who were located remained asymptomatic (77.8%). If the worst scenario was applied, a 62.0% cure rate (31/50) was obtained.. A 12-month regimen with a minimum of four anti-tuberculosis agents at full dose, essentially selected on drug sensitivity testing, could be an alternative option for the treatment of drug-resistant pulmonary tuberculosis.

Topics: Adolescent; Adult; Antibiotics, Antitubercular; Antitubercular Agents; Drug Administration Schedule; Ethambutol; Female; Follow-Up Studies; Humans; Isoniazid; Male; Middle Aged; Outcome Assessment, Health Care; Prospective Studies; Pyrazinamide; Rifampin; Streptomycin; Time Factors; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

To study the degree of adhesion, efficacy, and tolerance of therapeutic guidelines advocated by the National Consensus on tuberculosis.. A prospective study of a cohort of 84 patients receiving a diagnosis of tuberculosis in a Basic General Health Area between 1-3-1993 and 28-2-1994 treated with the regimen recommended by the National Council. The patients were evaluated clinically and microbiologically during the treatment and during twelve months follow-up.. Fifty-two patients (61.9%) were male and 32 (38.1%) female, aged 29.9 +/- 19.7 years (r = 1-84 years). Seventy-four (88.1%) were index cases and 10 (11.4%) household contacts. Eight patients (9.5%) were also infected with HIV, 71 (84.5%) presented pulmonary tuberculosis and 13 (15.5%) extrapulmonary forms. Therapeutic compliance was correct in 80 cases (95.2%) and incorrect in 4 (4.8%). It was well-tolerated in 73 patients (91.2%), there was slight toxicity in five (6.3%) and severe in two (2.5%). Seventy-four patients (88.1%) were cured, there was one therapeutic failure (1.2%) and five relapses (6%). Overall mortality was 4.8% and attributable mortality 1.2%.. Our results seem to confirm a high degree of adhesion, good tolerance and acceptable therapeutic efficacy of the scheme proposed by the National Council.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Anti-Bacterial Agents; Antitubercular Agents; Child; Child, Preschool; Drug Therapy, Combination; Female; HIV Infections; Humans; Infant; Isoniazid; Male; Middle Aged; Patient Compliance; Prospective Studies; Pyrazinamide; Recurrence; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

The aim of this study was to know the demographic profile of the new cases of tuberculosis (TB) and evaluate the current status of resistance to antituberculous drugs in Madrid, Spain.. A transversal study was carried out in 8 hospitals (6 general hospitals) during 6 months. The clinical data of patients over 14 years old who presented a positive culture for Mycobacterium tuberculosis were collected in a protocolized method; the study on sensitivity to 5 drugs was independently and centrally performed (proportions method).. 467 patients (339 from general hospitals), were included. In respect to the latter patients, 71% were under the age of 45 years and 36% presented coinfection with the human immunodeficiency virus (HIV). A sensitivity study was performed in 419 strains. Forty strains showed resistance to one or more of the antituberculous drugs; 13 were from the same center (CIC) in which a nosocomial outbreak of multiresistent TB had been detected among HIV infected patients. Resistence to more than one drug was observed in 29 cases (6.9%) and to rifampicine (RIF) and isoniacide (INH) in 24 patients (5.7%). On excluding the patients from the CIC these values were 16 (4.1%) and 13 (3.3%), respectively. Ninety-two percent of the strains with resistence to RIF + INH were from HIV positive patients. The rate of primary resistence to iNH in the patients with TB without HIV infection was 2.7%. This rate was 9.3% in those with HIV infection, and was 5.7% on excluding CIC cases. In patients with HIV infection most of the strains with primary resistence to INH also presented primary resistance to RIF.. More than one third of the patients with TB diagnosed in the general hospitals in Madrid, presented coinfection with HIV. In this population, the initial treatment for TB should probably begin with 4 drugs while awaiting the obliged sensitivity study.

Topics: Adolescent; Adult; Antibiotics, Antitubercular; Antitubercular Agents; Drug Resistance, Multiple; Ethambutol; Female; HIV Infections; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Rifampin; Spain; Streptomycin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

There is growing concern, even among developed countries, about the increasing incidence of multidrug-resistant tuberculosis (MDR-TB). Results are reported from a study investigating ofloxacin used in the treatment of 57 patients with MDR-TB. Patients received ofloxacin 400 mg/day as well as three other sensitive anti-TB drugs based on susceptibility tests. Treatment duration was 9 months. Preliminary results of 35 evaluable patients show 55% of MDR-TB cases converted to smear and culture negative within 3 months of therapy. Ofloxacin in combination with other sensitive anti-TB medication shows promise in the treatment of MDR-TB and further studies are recommended.

Topics: Adult; Drug Resistance, Multiple; Drug Therapy, Combination; Female; Humans; Indonesia; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Nausea; Ofloxacin; Prospective Studies; Pyrazinamide; Rifampin; Tuberculosis, Multidrug-Resistant

We studied 266 patients with drug-resistant pulmonary tuberculosis at national sanatoria in Japan. The patients included 218 men (mean age, 58 years) and 48 women (mean age, 62 years). The levels of isoniazid and rifampicin resistance were determined at 1 mcg/mL and 50 mcg/mL, respectively. The results were as follows. (1) Most patients with drug-resistant pulmonary tuberculosis were middle-aged or past middle-aged. (2) There were many cases of drug-resistant pulmonary tuberculosis in previously treated tuberculosis patients with active disease and several cases in previously untreated pulmonary tuberculosis patients. However, in some previously untreated patients active tuberculosis was convert relatively easily to inactive tuberculosis. (3) Concerning life style, bachelors who drank heavily were more likely to develop drug-resistant pulmonary tuberculosis. (4) Most cases of drug-resistant pulmonary tuberculosis had at least one cavity on chest radiographs. (5) Several patients with drug-resistant tuberculosis left the hospital against the advice of their attending doctors; therefore, it was difficult to treat their illnesses. (6) In more than half the cases in which Mycobacterium tuberculosis was resistant to isoniazid and rifampicin, tolerance to streptomycin and ethanbutol was also seen. (7) When patients with drug-resistant pulmonary tuberculosis continued to have tuberculous bacilli in their sputum after 3 months of chemotherapy, there was a tendency for them to expectorate tuberculous bacilli in their sputum. For these drug-resistant tuberculosis patients, we must pay attention not only to the medical aspects but also to the social aspects of their disease.

Topics: Adult; Aged; Aged, 80 and over; Antitubercular Agents; Female; Humans; Isoniazid; Life Style; Male; Middle Aged; Prognosis; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Outcomes of retreatment for rifampicin-resistant tuberculosis (RR-TB) are rarely reported. We report 'definitive outcomes' after a cascade approach to RR-TB treatment. After a bacteriologically adverse outcome for the 9-months fluoroquinolone-based Short Treatment Regimen (STR), patients were retreated with a bedaquiline-based regimen (BDQ-regimen).. A Retrospective cohort study of RR-TB patients treated with the STR during 2012-2019 and retreated with a BDQ-regimen in case of failure or relapse was conducted. Definitive relapse-free cure took into account BDQ-regimen outcomes.. Of 367 patients treated with the STR, 20 (5.4%) experienced failure or relapse. Out of these 20 patients, 14 started a BDQ-regimen, of whom none experienced failure or relapse. Definitive end of treatment outcomes of STR after revising with third-line BDQ-regimen outcomes, 84.7% (311/367) were cured relapse-free, 10.6% (39/367) died during treatment and 3.0% (11/367) were lost to follow-up during treatment with either the STR or BDQ-regimen. Six patients (1.6%; 6/367) with STR failure/relapse died before starting a BDQ-regimen. No patient had definitive treatment failure or relapse and remained without treatment.. If fluoroquinolone resistance is excluded or rare, it is beneficial to use fluoroquinolone as the core drug for a first RR-TB treatment regimen and to safeguard bedaquiline for those in need of retreatment.

Topics: Antitubercular Agents; Fluoroquinolones; Humans; Niger; Retrospective Studies; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant

Since the roll-out of the Xpert MTB/RIF assay, continuous surveillance can provide an estimate of rifampicin-resistant TB (RR-TB) prevalence, provided high drug susceptibility testing (DST) coverage is achieved. We use national data from Rwanda to describe rifampicin DST coverage, estimate the prevalence of RR-TB and assess its predictors.. Routinely collected DST data were entered into an electronic TB case-based surveillance system. DST coverage was calculated among all bacteriologically confirmed pulmonary TB patients notified from 1 July 2019 to 30 June 2020 in Rwanda. The prevalence of RR-TB was estimated among those with DST results. Univariable and multivariable analysis was performed to explore predictors for RR TB.. Among 4066 patients with bacteriologically confirmed pulmonary TB, rifampicin DST coverage was 95.6% (4066/4251). RR-TB was diagnosed in 73 patients. The prevalence of RR-TB was 1.4% (53/3659; 95% CI 1.09 to 1.89%) and 4.9% (20/406; 95% CI 3.03 to 7.51%) in new and previously treated TB cases, respectively. Predictors of RR-TB were: (1) living in Kigali City (adjusted OR [aOR] 1.65, 95% CI 1.03 to 2.65); (2) previous TB treatment (aOR 3.64, 95% CI 2.14 to 6.19); and (3) close contact with a known RR-TB patient (aOR 11.37, 95% CI 4.19 to 30.82).. High rifampicin DST coverage for routine reporting allowed Rwanda to estimate the RR-TB prevalence among new and previously treated patients.

Topics: Antibiotics, Antitubercular; Cross-Sectional Studies; Drug Resistance, Bacterial; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Rwanda; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Rifampin-resistant and/or multidrug-resistant tuberculosis (RR/MDR-TB) treatment requires multiple drugs, and outcomes remain suboptimal. Some drugs are associated with improved outcome. It is unknown whether particular pharmacokinetic-pharmacodynamic relationships predict outcome.. Adults with pulmonary RR/MDR-TB in Tanzania, Bangladesh, and the Russian Federation receiving local regimens were enrolled from June 2016 to July 2018. Serum was collected after 2, 4, and 8 weeks for each drug's area under the concentration-time curve over 24 hours (AUC0-24). Quantitative susceptibility of the M. tuberculosis isolate was measured by minimum inhibitory concentrations (MICs). Individual drug AUC0-24/MIC targets were assessed by adjusted odds ratios (ORs) for favorable treatment outcome, and hazard ratios (HRs) for time to sputum culture conversion. K-means clustering algorithm separated the cohort of the most common multidrug regimen into 4 clusters by AUC0-24/MIC exposures.. Among 290 patients, 62 (21%) experienced treatment failure, including 30 deaths. Moxifloxacin AUC0-24/MIC target of 58 was associated with favorable treatment outcome (OR, 3.75; 95% confidence interval, 1.21-11.56; P = .022); levofloxacin AUC0-24/MIC of 118.3, clofazimine AUC0-24/MIC of 50.5, and pyrazinamide AUC0-24 of 379 mg × h/L were associated with faster culture conversion (HR >1.0, P < .05). Other individual drug exposures were not predictive. Clustering by AUC0-24/MIC revealed that those with the lowest multidrug exposures had the slowest culture conversion.. Amidst multidrug regimens for RR/MDR-TB, serum pharmacokinetics and M. tuberculosis MICs were variable, yet defined parameters to certain drugs-fluoroquinolones, pyrazinamide, clofazimine-were predictive and should be optimized to improve clinical outcome.. NCT03559582.

Topics: Adult; Antitubercular Agents; Clofazimine; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Prospective Studies; Pyrazinamide; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Rapid tuberculosis (TB) drug susceptibility testing (DST) is crucial. Genotype MTBDRsl is a widely deployed World Health Organization (WHO)-endorsed assay. Programmatic performance data, including non-actionable results from smear-negative sputum, are scarce.. Sputa from Xpert MTB/RIF individuals (n = 951) were routinely-tested using Genotype MTBDRplus and MTBDRsl (both version 2). Phenotypic DST was the second-line drug reference standard. Discrepant results underwent Sanger sequencing.. 89% (849 of 951) of individuals were culture-positive (56%, 476 of 849 smear-negative). MTBDRplus had at least 1 nonactionable result (control and/or TB-detection bands absent or invalid, precluding resistance reporting) in 19% (92 of 476) of smear-negatives; for MTBDRsl, 40% (171 of 427) were nonactionable (28%, 120 of 427 false-negative TB; 17%, 51 of 427 indeterminate). In smear-negatives, MTBDRsl sensitivity for fluoroquinolones was 84% (95% confidence interval, 67%-93), 81% (54%-95%) for second-line injectable drugs, and 57% (28%-82%) for both. Specificities were 93% (89%-98%), 88% (81%-93%), and 97% (91%-99%), respectively. Twenty-three percent (172 of 746) of Xpert rifampicin-resistant specimens were MTBDRplus isoniazid-susceptible. Days-to-second-line-susceptibility reporting with the programmatic advent of MTBDRsl improved (6 [5-7] vs 37 [35-46]; P < .001).. MTBDRsl did not generate a result in 4 of 10 smear-negatives, resulting in substantial missed resistance. However, if MTBDRsl generates an actionable result, that is accurate in ruling-in resistance. Isoniazid DST remains crucial. This study provides real-world, direct, second-line susceptibility testing performance data on non-actionable results (that, if unaccounted for, cause an overestimation of test utility), accuracy, and care cascade impact.

Topics: Antitubercular Agents; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis; Tuberculosis, Multidrug-Resistant

The control of drug-resistant tuberculosis (TB) is a major challenge. The frequency and mutation characteristics indicate the efficiency of molecular tests for the rapid detection of TB drug resistance. This study examined the existence of katG and inhA mutations for isoniazid (INH) resistance and rpoB mutations for rifampicin (RFP) resistance. In total, 178 drug-resistant Mycobacterium tuberculosis (MTB) isolates were analyzed. Mutations in katG encoding and inhA regulatory regions were detected in 136/168 (81.0%) and 29/168 (17.3%), respectively, with the most prominent mutation of Ser315Thr substitution in katG in 126/168 (75.0%), and -15 C to T substitution in the regulatory region of the inhA (26/168; 15.5%). Two distinct katG mutations (Tyr337Cys, 1003InsG) were identified. Of 125 RFP-resistant isolates, 118 (94.4%) carried mutations affecting the 81-bp RFP resistance-determining region, with the most commonly affected codons 450, 445, and 435 identified in 74 (59.2%), 26 (20.8%), and 12 (9.6%) isolates, respectively. Genetic mutations were highly associated with phenotypic INH and RFP resistance, and the majority shared similarities with those reported in previous studies in Thailand and other Asian countries. These data are useful for guiding the use and improvement of molecular tests for TB drug resistance.

Topics: Antitubercular Agents; Bacterial Proteins; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifampin; Thailand; Tuberculosis, Multidrug-Resistant

Four moderate-complexity automated nucleic acid amplification tests for the diagnosis of tuberculosis are reported as having laboratory analytical and clinical performance similar to that of the Cepheid Xpert MTB/RIF assay. These assays are the Abbott RealTime MTB and RealTime MTB RIF/INH Resistance, Becton Dickinson MAX MDR-TB, the Hain Lifescience/Bruker FluoroType MTBDR, and the Roche cobas MTB and MTB RIF/INH assays. The study compared feasibility, ease of use, and operational characteristics of these assays/platforms. Manufacturer input was obtained for technical characteristics. Laboratory operators were requested to complete a questionnaire on the assays' ease of use. A time-in-motion analysis was also undertaken for each platform. For ease-of-use and operational requirements, the BD MAX MDR-TB assay achieved the highest scores (86% and 90%) based on information provided by the user and manufacturer, respectively, followed by the cobas MTB and MTB-RIF/INH assay (68% and 86%), the FluoroType MTBDR assay (67% and 80%), and the Abbott RT-MTB and RT MTB RIF/INH assays (64% and 76%). The time-in-motion analysis revealed that for 94 specimens, the RealTime MTB assay required the longest processing time, followed by the cobas MTB assay and the FluoroType MTBDR assay. The BD MAX MDR-TB assay required 4.6 hours for 22 specimens. These diagnostic assays exhibited different strengths and weaknesses that should be taken into account, in addition to affordability, when considering placement of a new platform.

Topics: Feasibility Studies; Humans; Isoniazid; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Rifampin; Sensitivity and Specificity; Tuberculosis; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; World Health Organization

Linezolid (LZD) is an effective drug in treating multidrug-resistant tuberculosis and extensively drug-resistant tuberculosis. This study aimed to evaluate the safety of LZD in the treatment of patients with rifampicin resistant tuberculosis. This was a multicenter retrospective study. A total of 184 patients of the rifampicin resistant tuberculosis patients treated with LZD from Jan 2018 to Apr 2020 in three hospitals were involved, and their clinical symptoms were recorded and analyzed. Meanwhile, the types and incidence of adverse effects associated with LZD were evaluated. It showed that peripheral neuritis (51, 27.7%) and hemochromatosis (42, 22.8%) were the most common adverse effects observed among these patients. The median time of symptoms after LZD treatment was 45.5 and 120.0 days, respectively. Furthermore, female patients had a significantly higher risk for leukopenia (P = 0.002) and hemochromatosis (P = 0.033) when compared with male patients. History of underlying disease was the risk factor for thrombocytopenia (P = 0.022). Patients with long duration of medication (RR = 1.004, 95%CI: 1.002-1.006, P < 0.001) and daily dosage ≥600mg (RR = 3.059, 95%CI: 1.238-7.558, P = 0.015) were at higher risk of hemochromatosis. Age was the risk factor for rash (P = 0.008) and nausea and vomiting (P = 0.018). In addition, LZD administration time was the risk factor for optic neuritis (P < 0.001) and peripheral neuritis (P < 0.001). LZD can cause adverse symptoms in patients with rifampicin resistant tuberculosis. Gender, history of underlying disease, LZD use time, LZD dosage, and age are the risk factors in the LZD treatment of these patients. During medication, bone marrow suppression and neuropathy should be closely monitored. This study could potentially provide useful information for the clinical practice.

Topics: Antitubercular Agents; Drug-Related Side Effects and Adverse Reactions; Female; Hemochromatosis; Humans; Linezolid; Male; Neuritis; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant

World Health Organization recommends a 7-drug 9-11-month rifampicin-resistant tuberculosis (RR-TB) short treatment regimen (STR). To reduce the pill burden, we assessed the safety and effectiveness of a 5-drug 9-11-month modified STR (mSTR).. Prospective cohort study of an all-oral mSTR (comprising bedaquiline, levofloxacin, linezolid [LZD], clofazimine, and/or pyrazinamide) for patients with RR-TB without confirmed fluoroquinolone resistance, enrolled in Vietnam between 2020-2021.. A total of 108 patients were enrolled in this study. Overall, 63 of 74 (85%) achieved culture conversion at 2 months. Of 106 evaluated, 95 (90%) were successfully treated, six (6%) were lost-to-follow-up, one (1%) died, and four (4%) had treatment failure, including three with permanent regimen change owing to adverse events (AE) and one with culture reversion. Of 108, 32 (30%) patients encountered at least one AE. Of 45 AEs recorded, 13 (29%) were serious (hospitalization, life threatening, or death). The median time to AE was 3 months (IQR: 2-5). A total of 26 AEs led to regimen adaptation: either dose reduction (N = 1), drug temporary interruption (N = 19), or drug permanent discontinuation (N = 6, 4 attributed to LZD).. The high treatment success of 5-drug mSTR might replace the 7-drug regimen in routine care. AEs were frequent, but manageable in most patients. Active AEs monitoring is essential, particularly when using LZD throughout.

Topics: Antitubercular Agents; Diarylquinolines; Humans; Linezolid; Prospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant; Vietnam

To investigate the time to treatment initiation (TTI) for multidrug-resistant/rifampicin-resistant tuberculosis (MDR/RR-TB) patients after diagnosis in Indonesia and biological, psychological and social factors associated with the time interval.. This study was conducted in Persahabatan Hospital, Jakarta using a mixed-methods approach. Registry data and medical records of MDR/RR-TB patients were collected and matched (hospital dataset), and linked with psychosocial assessment results (linked dataset). Descriptive analysis was conducted to understand patient characteristics and the distribution of TTI after RR-TB diagnosis by GeneXpert. Generalised linear regression was used to analyse factors associated with delay duration, and logistic regression to explore factors associated with the delay longer than the median duration for both datasets (basic vs. extended model). In-depth interviews were conducted with patients and healthcare workers to understand the procedure of treatment initiation and how different factors led to delay.. The hospital dataset included 275 patient-matched cases, and 188 were further linked with psychosocial assessment results. The median time interval was 24 days [interquartile range (IQR) 23.5] and 26 days (IQR 21.25), respectively. Regression analysis showed that in the extended model, comorbidities (exp [coefficient]= 1.93), unemployment (exp [coefficient] = 1.80) and poor knowledge of MDR/RR-TB (exp (coefficient) = 1.67) seemed to have the strongest effects on prolonging the time interval (p < 0.05). Unsuccessful TB treatment history was the only factor that significantly increased the risk of delay longer than the median duration (p < 0.05) in the basic model, while none of the factors were significant in the extended model. The qualitative study identified provider-side factors (centralised service provision and insufficient human resources) and patient-side factors (physical weakness, psychological stress and financial concern) associated with treatment delay.. MDR/RR-TB patients in Persahabatan Hospital, Jakarta, Indonesia waited around 25 days for treatment initiation after RR-TB diagnosis. Health system solutions are needed to address challenges facing both MDR/RR-TB patients and healthcare providers to reduce delay in treatment initiation.

Topics: Antitubercular Agents; Humans; Indonesia; Mycobacterium tuberculosis; Outcome Assessment, Health Care; Rifampin; Time-to-Treatment; Tuberculosis, Multidrug-Resistant

The alarming increase in multidrug resistance, which includes Bedaquiline and Delamanid, stumbles success in Tuberculosis treatment outcome. Mycobacterium tuberculosis gains resistance to rifampicin, which is one of the less toxic and potent anti-TB drugs, through genetic mutations predominantly besides efflux pump mediated drug resistance. In recent decades, scientific interventions are being carried out to overcome this hurdle using novel approaches to save this drug by combining it with other drugs/molecules or by use of high dose rifampicin. This study reports five small molecules namely Ellagic acid, Methyl Stearate, Myoinositol, Rutin, and Shikimic acid that exhibit synergistic inhibitory activity with rifampicin against resistant TB isolates. In-silico examinations revealed possible blocking of Rv1819c-an ABC transporter efflux pump that was known to confer resistance in M. tuberculosis to rifampicin. The synergistic anti-TB activity was assessed using a drug combination checkerboard assay. Efflux pump inhibition activity of ellagic acid, myoinositol, and methyl stearate was observed through ethidium bromide accumulation assay in the drug-resistant M. tuberculosis clinical strains and recombinant Mycobacterium smegmatis expressing Rv1819c in coherence with the significant reduction in the minimum inhibitory concentration of rifampicin. Cytotoxicity of the active efflux inhibitors was tested using in silico and ex vivo methods. Myoinositol and methyl stearate were completely non-toxic to the hematological and epithelial cells of different organs under ex vivo conditions. Based on these findings, these molecules can be considered for adjunct TB therapy; however, their impact on other drugs of anti-TB regimen needs to be tested.

Topics: Antitubercular Agents; Ellagic Acid; Humans; Inositol; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Stearates; Tuberculosis, Multidrug-Resistant

Topics: Antibiotics, Antitubercular; Antitubercular Agents; Cost-Benefit Analysis; Drug Resistance, Bacterial; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

A simple, rapid and low-cost diagnostic test, which can detect both the drug-sensitive and the drug-resistant tuberculosis (TB) cases is the need of the hour. Here, we developed a Cas9/gRNA-assisted quantitative Real-Time PCR (qRT-PCR) (CARP) assay to detect single nucleotide mutations causing drug resistance in the TB pathogen, Mycobacterium tuberculosis (Mtb). Guide RNAs (gRNAs) were designed against S531 and H526 positions in the rifampicin (RIF)-resistance-determining region (RRDR) of the Mtb rpoB gene that exhibit frequent mutations in the RR clinical isolates of Mtb. Conditions were optimised for in vitro Cas9 cleavage such that single nucleotide changes at these positions can be recognised by Cas9/gRNA complex with high sensitivity and 100% specificity. Further estimation of Cas9/gRNA-based cleavage of target DNA by qRT-PCR led to rapid detection of drug-resistant sequences. The newly designed CARP assay holds a great deal of promise in the diagnosis and prognosis of patients suffering from TB, in a cost-effective manner.

Topics: Animals; Bacterial Proteins; Carps; CRISPR-Cas Systems; DNA-Directed RNA Polymerases; Drug Resistance, Bacterial; Humans; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Point Mutation; Real-Time Polymerase Chain Reaction; Rifampin; Tuberculosis, Multidrug-Resistant

Resistance to isoniazid (INH) and rifampicin (RIF) first-line drugs in Mycobacterium tuberculosis (Mtb), together called multi-drug resistance, threatens tuberculosis control. Resistance mutations in katG (for INH) and rpoB (RIF) genes often come with fitness costs. To overcome these costs, Mtb compensatory mutations have arisen in rpoC/rpoA (RIF) and ahpC (INH) loci. By leveraging the presence of known compensatory mutations, we aimed to detect novel resistance mutations occurring in INH and RIF target genes. Across ~ 32 k Mtb isolates with whole genome sequencing (WGS) data, there were 6262 (35.7%) with INH and 5435 (30.7%) with RIF phenotypic resistance. Known mutations in katG and rpoB explained ~ 99% of resistance. However, 188 (0.6%) isolates had ahpC compensatory mutations with no known resistance mutations in katG, leading to the identification of 31 putative resistance mutations in katG, each observed in at least 3 isolates. These putative katG mutations can co-occur with other INH variants (e.g., katG-Ser315Thr, fabG1 mutations). For RIF, there were no isolates with rpoC/rpoA compensatory mutations and unknown resistance mutations. Overall, using WGS data we identified putative resistance markers for INH that could be used for genotypic drug-resistance profiling. Establishing the complete repertoire of Mtb resistance mutations will assist the clinical management of tuberculosis.

Topics: Antitubercular Agents; Bacterial Proteins; Genomics; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR) is a frequently used typing method for identifying the Beijing genotype of Mycobacterium tuberculosis (Mtb), which is easily transformed into rifampicin (RIF) resistance. The RIF resistance of Mtb is considered to be highly related with the mutation of rpoB gene. Therefore, this study aimed to analyze the relationship between the repetitive number of MIRU loci and the mutation of rpoB gene.. An open-source whole-genome sequencing data of Mtb was used to detect the mutation of rpoB gene and the repetitive number of MIRU loci by bioinformatics methods. Cochran-Armitage analysis was performed to analyze the trend of the rpoB gene mutation rate and the repetitive number of MIRU loci.. Among 357 rifampicin-resistant tuberculosis (RR-TB), 304 strains with mutated rpoB genes were detected, and 6 of 67 rifampicin susceptible strains were detected mutations. The rpoB gene mutational rate showed an upward trend with the increase of MIRU10, MIRU39, QUB4156 and MIRU16 repetitive number, but only the repetitive number of MIRU10, MRIU39 and QUB4156 were risk factors for rpoB gene mutation. The Hunter-Gaston discriminatory index (HGDI) of MIRU10 (0.65) and QUB4156 (0.62) was high in the overall sample, while MIRU39 (0.39) and MIRU16 (0.43) showed a moderate discriminatory Power.. The mutation rate of rpoB gene increases with the addition of repetitive numbers of MIRU10, QUB4156 and MIRU39 loci.

Topics: Bacterial Proteins; Bacterial Typing Techniques; DNA-Directed DNA Polymerase; Genotype; Humans; Minisatellite Repeats; Mutation Rate; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Establishing simple, rapid, and highly sensitive molecular assays is crucial for timely diagnosis and effective treatment of drug-resistant tuberculosis. However, current genotypic drug susceptibility testing (DST) still encounters enormous challenges including lower sensitivity than phenotypic DST and insufficient accuracy. Herein, a simple, low-cost, multiplex real-time polymerase chain reaction-based assay is established to achieve highly sensitive detection of low-abundant mutants through competitive wild-type blocking (COWTB). Analytical performance of the COWTB assay can achieve 1% or even 0.1% mutants under background of 10 000 wild-type genomes/test. Furthermore, clinical practice feasibility is evaluated to identify resistance to rifampicin (RIF), isoniazid (INH), and streptomycin (SM) on 92 actual clinical samples, its sensitivity is 93.8% for RIF and 100% for INH and SM, and specificity is 100% each for RIF, INH, and SM when using DNA sequencing as the reference standard. In comparison, the sensitivity of reverse dot blotting assay commonly used in clinics is 93.8%, 90.0%, and 84.6%, and the specificity is 96.1%, 98.6%, and 100% for RIF, INH, and SM, respectively. Importantly, the COWTB assay can also be applicable for other drug-resistant mutations and pave a promising detection strategy to fill the gap between phenotypic and genotypic DST for detecting low-abundant drug-resistant M. tuberculosis.

Topics: Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Humans; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Streptomycin; Tuberculosis, Multidrug-Resistant

The cure rate of multidrug-resistant and rifampicin-resistant pulmonary tuberculosis in the world is about 60%, and timely surgical intervention can increase the cure rate to more than 85%. The treatment of multidrug-resistant and rifampicin-resistant pulmonary tuberculosis requires multidisciplinary involvement of tuberculosis department, thoracic surgery department, imaging department, laboratory department and other disciplines to significantly reduce its morbidity and mortality. Although the World Health Organization has defined the role and status of surgery in the treatment of multidrug-resistant and rifampicin-resistant pulmonary tuberculosis, there are significant differences in the cognition and diagnosis and treatment methods of domestic clinicians on multidrug-resistant and rifampicin-resistant pulmonary tuberculosis. Therefore, it is urgent to develop expert consensus on surgical treatment of multidrug-resistant and rifampicin-resistant pulmonary tuberculosis for clinicians to learn from in clinical diagnosis and treatment practice. The Chinese Society for Tuberculosis,Chinese Medical Association organized experts in tuberculosis thoracic surgery to write the first draft of consensus based on the expert suggestion on surgical diagnosis and treatment of multidrug-resistant pulmonary tuberculosis written by the European Office of the World Health Organization in 2014 and the 2019 version of China's multidrug-resistant and rifampicin-resistant pulmonary tuberculosis expert consensus, and combined with China's national situation. This consensus systematically elaborated seven aspects, including surgical indications, contraindications to surgery, conditions and timing of surgery, surgical methods and indications of various surgical procedures, preoperative and postoperative chemotherapy, treatment of surgical complications, and perioperative management of patients with multidrug-resistant and rifampin-resistant pulmonary tuberculosis. After discussion and voting by experts, six recommendations were formed, aiming to provide reference for clinicians in the treatment of multidrug-resistant and rifampin-resistant pulmonary tuberculosis and further improve the standardized diagnosis and treatment level of multidrug-resistant and rifampin-resistant pulmonary tuberculosis in China.. 耐多药和利福平耐药肺结核（MDR/RR-PTB）治愈率在60%左右，外科的及时干预可将治愈率提高至85%以上。MDR/RR-PTB的治疗需要结核科、胸外科、影像科、检验科等多学科共同参与，才能明显降低其病死率。世界卫生组织虽已经明确外科手术在MDR/RR-PTB治疗中的作用和地位，但是国内临床医生对其认知和诊疗方法存在较大差异，因此亟须制定MDR/RR-PTB外科治疗专家共识，供临床医师在临床诊治实践中借鉴。中华医学会结核病学分会组织结核胸外科相关专家，基于2014年世界卫生组织欧洲工作处撰写的《耐多药肺结核外科诊疗专家建议》及《中国耐多药和利福平耐药结核病治疗专家共识（2019年版）》，结合我国国情共同撰写了本共识。本共识对MDR/RR-PTB的手术适应证、外科手术禁忌证、手术的条件和时机、手术方式及各种术式适应证、术前术后化疗、手术并发症的处理、患者围手术期管理等7个方面进行了系统的阐述，经专家讨论和投票，共形成6条推荐意见，旨在为临床医生治疗MDR/RR-PTB提供参考，进一步提高我国MDR/RR-PTB规范化诊疗水平。.

Topics: Antitubercular Agents; China; Consensus; Humans; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

The treatment outcomes of patients with multidrug/rifampin-resistant (MDR/RR) tuberculosis (TB) are important indicators that reflect the current status of TB management and identify the key challenges encountered by TB control programs in a country.. We retrospectively evaluated the treatment outcomes as well as predictors of unfavorable outcomes in patients with MDR/RR-TB notified from 2011 to 2017, using an integrated TB database.. A total of 7,226 patients with MDR/RR-TB were included. The treatment success rate had significantly increased from 63.9% in 2011 to 75.1% in 2017 (. The treatment outcomes of patients with MDR/RR-TB has gradually improved but increasing deaths during treatment is an emerging challenge for MDR-TB control in Korea. Targeted and comprehensive care is needed for vulnerable patients such as the elderly, patients with comorbidities, and those with low household incomes.

Topics: Aged; Antitubercular Agents; Humans; Male; Mycobacterium tuberculosis; Republic of Korea; Retrospective Studies; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant

Tuberculosis (TB), caused by the bacterium Mycobacterium tuberculosis is one of the top thirteen causes of death worldwide. The major challenge to control TB is the emergence of drug-resistant tuberculosis (DR-TB); specifically, multi-drug resistant TB which are resistant to the most potent drugs; rifampin and isoniazid. Owing to the inconsistencies of the current diagnostic methods, a single test cannot identify the whole spectrum of DR-TB associated mutations. Recently, host blood transcriptomics has gained attention as a promising technique that develops disease-specific RNA signatures/biomarkers. However, studies on host transcriptomics infected with DR-TB is limited. Herein, we intended to identify genes/pathways that are differentially expressed in multi-drug/rifampin resistant TB (MDR/RR-TB) in contrast to drug susceptible TB.. We conducted blood RNA sequencing of 10 pulmonary TB patients (4; drug susceptible and 6; DR-TB) and 55 genes that were differentially expressed in MDR/RR-TB from drug-susceptible/mono-resistant TB were identified. CD300LD, MYL9, VAMP5, CARD17, CLEC2B, GBP6, BATF2, ETV7, IFI27 and FCGR1CP were found to be upregulated in MDR/RR-TB in all comparisons, among which CLEC2B and CD300LD were not previously linked to TB. In comparison pathway analysis, interferon alpha/gamma response was upregulated while Wnt/beta catenin signaling, lysosome, microtubule nucleation and notch signaling were downregulated.. Up/down-regulation of immunity related genes/pathways speculate the collective effect of hosts' attempt to fight against continuously multiplying DR-TB bacteria and the bacterial factors to fight against the host defense. The identified genes/pathways could act as MDR/RR-TB biomarkers, hence, further research on their clinical use should be encouraged.

Topics: Antitubercular Agents; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Pilot Projects; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Hematogenous disseminated tuberculosis predisposes to concurrent tuberculous meningitis (TBM), the most devastating and disabling form of tuberculosis. However, children often have atypical clinical symptoms, difficulty in specimen collection, low specimen content, and an increasing incidence of drug-resistant tuberculosis. Thus, the accurate diagnosis and timely treatment of childhood tuberculosis face monumental challenges.. The 14-year-old female presented to the hospital with intermittent fever, headache, and blurred vision. Her cerebrospinal fluid (CSF) showed a lymphocytic pleocytosis, an elevated protein level, and a decreased chloride level. And her CSF tested positive for TB-RNA. Xpert MTB/RIF detected Mycobacterium tuberculosis in her CSF, but the rifampin resistance test was unknown. Subsequently, her CSF culture was positive for Mycobacterium tuberculosis. The drug sensitivity test (DST) revealed resistance to isoniazid, rifampin, and fluoroquinolones. A computed tomography (CT) of the chest showed diffuse miliary nodules in both lungs. Intracranial enhanced magnetic resonance imaging (MRI) showed "multiple intensified images of the brain parenchyma, cisterns, and part of the meninges." The final diagnosis is miliary pulmonary tuberculosis and pre-extensive drug-resistant TBM. After 19 months of an oral, individualized antituberculosis treatment, she recovered with no significant neurological sequelae.. For patients with miliary pulmonary tuberculosis, especially children, even if there are no typical clinical symptoms, it is necessary to know whether there is TBM and other conditions. Always look for the relevant aetiological basis to clarify whether it is drug-resistant tuberculosis. Only a rapid and accurate diagnosis and timely and effective treatment can improve the prognosis and reduce mortality and disability rates.

Topics: Adolescent; Child; Female; Humans; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis, Meningeal; Tuberculosis, Miliary; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

While the goal of universal drug susceptibility testing has been a key component of the WHO End TB Strategy, in practice, this remains inaccessible to many. Rapid molecular tests for tuberculosis (TB) and antituberculosis drug resistance could significantly improve access to testing. In this study, we evaluated the accuracy of the Akonni Biosystems XDR-TB (extensively drug-resistant TB) TruArray and lateral-flow-cell (XDR-LFC) assay (Akonni Biosystems, Inc., Frederick, MD, USA), a novel assay that detects mutations in seven genes associated with resistance to antituberculosis drugs:

Topics: Amikacin; Antitubercular Agents; Bacterial Proteins; Capreomycin; Drug Resistance, Multiple, Bacterial; Extensively Drug-Resistant Tuberculosis; Fluoroquinolones; Humans; Isoniazid; Kanamycin; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Prospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant

Drug-resistant tuberculosis (DR-TB) posed challenges to global TB control. Whole-genome sequencing (WGS) is recommended for predicting drug resistance to guide DR-TB treatment and management. Nevertheless, data are lacking in Taiwan. Phenotypic drug susceptibility testing (DST) of 12 anti-TB drugs was performed for 200 Mycobacterium tuberculosis isolates. WGS was performed using the Illumina platform. Drug resistance profiles and lineages were predicted in silico using the Total Genotyping Solution for TB (TGS-TB). Using the phenotypic DST results as a reference, WGS-based prediction demonstrated high concordance rates of isoniazid (95.0%), rifampicin (RIF) (98.0%), pyrazinamide (98.5%) and fluoroquinolones (FQs) (99.5%) and 96.0% to 99.5% for second-line injectable drugs (SLIDs); whereas, lower concordance rates of ethambutol (87.5%), streptomycin (88.0%) and ethionamide (84.0%). Furthermore, minimum inhibitory concentrations confirmed that RIF rpoB S450L, FQs gyrA D94G and SLIDs rrs a1401g conferred high resistance levels. Besides, we identified lineage-associated mutations in lineage 1 (rpoB H445Y and fabG1 c-15t) and predominant lineage 2 (rpoB S450L and rpsL K43R). The WGS-based prediction of drug resistance is highly concordant with phenotypic DST results and can provide comprehensive genetic information to guide DR-TB precision therapies in Taiwan.

Topics: Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Humans; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifampin; Taiwan; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Genomics; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Sputum; Tuberculosis; Tuberculosis, Multidrug-Resistant

Emerging

Topics: Antitubercular Agents; Bacterial Proteins; DNA-Directed RNA Polymerases; Drug Resistance, Bacterial; Humans; Mutation; Mycobacterium tuberculosis; Rifampin; RNA; Tuberculosis, Multidrug-Resistant

To describe long-term treatment outcomes in patients with multi-drug-resistant/rifampicin-resistant tuberculosis (MDR/RR-TB) and validate established outcome definitions for MDR/RR-TB treatment.. Among patients with MDR/RR-TB admitted to a German MDR/RR-TB referral centre from 1 September 2002 to 29 February 2020, we compared long-term treatment outcomes derived from individual patient follow-up with treatment outcomes defined by WHO-2013, WHO-2021 and the Tuberculosis Network European Trials Group-2016.. In a total of 163 patients (mean age, 35 years; standard deviation, 13 years; 14/163 [8.6%] living with HIV; 109/163 [66.9%] men, 149/163 [91.4%] migrating to Germany within 5 years), the treatment of culture-confirmed MDR/RR-TB was initiated. Additional drug resistance to a fluoroquinolone or a second-line injectable agent was present in 15 of the 163 (9.2%) Mycobacterium tuberculosis strains; resistance against both the drug classes was present in 29 of the 163 (17.8%) strains. The median duration of MDR/RR-TB treatment was 20 months (interquartile range, 19.3-21.6 months), with a medium of five active drugs included. The median follow-up time was 4 years (47.7 months; interquartile range, 21.7-65.8 months). Among the 163 patients, cure was achieved in 25 (15.3%), 82 (50.3%) and 95 (58.3%) patients according to the outcome definitions of WHO-2013, WHO-2021, and the Tuberculosis Network European Trials Group-2016, respectively. The lost to follow-up rate was 17 of 163 (10.4%). Death was more likely in patients living with HIV (hazard ratio, 4.28; 95% confidence interval, 1.26-12.86) and older patients (hazard ratio, 1.08; 95% confidence interval, 1.05-1.12; increment of 1 year). Overall, 101/163 (62.0%) patients experienced long-term, relapse-free cure; of those, 101/122 (82.8%) patients with a known status (not lost to-follow-up or transferred out) at follow-up.. Under optimal management conditions leveraging individualized treatment regimens, long-term, relapse-free cure from MDR/RR-TB is substantially higher than cure rates defined by current treatment outcome definitions.

Topics: Adult; Antitubercular Agents; Female; HIV Infections; Humans; Male; Mycobacterium tuberculosis; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant

Topics: Algorithms; Humans; Rifampin; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Humans; Rifampin; Tuberculosis, Multidrug-Resistant

Tuberculosis (TB) prophylactic therapy for latent infection, which can reduce the risk for the development of active TB, is an important measure in TB control. China recommends prophylactic therapy for latent tuberculosis infection (LTBI) in some key populations to reduce the risk for TB. Contacts of patients with multi-drug and rifampicin-resistant TB (MDR/RR-TB) are at high risk for the infection with drug-resistant pathogen, however, no unified prophylactic therapy regimen has been recommended for LTBI due to exposure to MDR/RR-TB patients. This paper summarizes the current MDR/RR-TB prophylactic therapy regimen and its protection effect based on the results of the retrieval of literature, guidelines, expert consensus and technical specifications to provide reference for the prevention and control of LTBI.. 对结核潜伏感染者开展预防性治疗可减少感染人群发生结核病的机会，是控制结核病的一项重要措施。我国推荐对部分重点人群的结核潜伏感染者开展预防性治疗，从而减少结核病发病的风险。耐多药/利福平耐药结核病患者接触者感染耐药病原体的风险高，但是目前对于接触耐多药/利福平耐药结核病患者的感染者还没有推荐的预防性治疗方案，本文检索文献、指南、专家共识和技术规范，对目前耐多药/利福平耐药结核病患者接触者预防性治疗方案和保护效果进行综述，为结核潜伏感染防控提供参考依据。.

Topics: Antitubercular Agents; China; Humans; Latent Tuberculosis; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

The present study used immunohistochemistry (IHC) to detect antigen Ag85B in tissue sections and aimed to evaluate its validity in histopathologic diagnosis of tuberculosis (TB).. In total, 204 patients with confirmed TB and 40 other diseases were included in the present study. Ziehl-Neelsen (Z-N) stains, IHC (anti-Ag85B), and quantitative fluorescence polymerase chain reaction were used to detect acid-fast bacilli, Mycobacterium tuberculosis (MTB) antigen, and MTB DNA.. Immunohistochemistry was significantly more sensitive than Z-N stains (93.1% vs 67.2%; P < .001). The sensitivity of Z-N stains significantly correlated with anti-TB treatment history. The sensitivity of Z-N stains was lower in rifampicin (RIF)-resistant TB compared with RIF-sensitive TB (52.8% vs 69.0%; P = .091) and those without treatment history (52.8% vs 84.0%; P = .015). However, IHC was not significantly affected by treatment history (P = .410). Moreover, expression patterns of Ag85B were dependent on treatment history and commonly showed weak scattered spots in RIF-susceptible TB. Conversely, strong brown rods were often found in those with RIF-resistant TB.. Immunohistochemistry is a simple, sensitive technique for the diagnosis of TB, especially for those patients with treatment history. The expression pattern of Ag85B is a potential marker for evaluating anti-TB treatment response.

Topics: Antitubercular Agents; Coloring Agents; Humans; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Rapid diagnosis of tuberculosis and drug resistance in extrapulmonary specimens can be challenging. The BD MAX™ multidrug resistant (MDR)-TB assay (BD MAX™) has demonstrated high sensitivity and specificity for the detection of the Mycobacterium tuberculosis complex (MTBC) as well as resistance to INH and Rifampin (RIF) in pulmonary specimens but has not been rigorously assessed in extrapulmonary samples. We evaluated the diagnostic accuracy of the BD MAX™ assay for the detection of MTBC and drug resistance in extrapulmonary specimens spiked with MTBC from the Johns Hopkins strain collection. A total of 1083 tests were performed across multiple sample types, with an overall percent agreement of 94.8% (795/839) for detection of MTBC and 99% (379/383) and 96.4% (323/335) for determination of INH and RIF resistance-conferring mutations, respectively. The BD MAX™ assay provides same day detection of MTBC and drug-resistance results and could be a beneficial diagnostic test in extrapulmonary sample types.

Topics: Antitubercular Agents; Feasibility Studies; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

Multidrug-resistant tuberculosis (MDR-TB) is among the most frequent causes of death due to antimicrobial resistance. Although only 3% of global TB cases are MDR, geographical hotspots with up to 40% of MDR-TB have been observed in countries of the former Soviet Union. While the quality of TB control and patient-related factors are known contributors to such hotspots, the role of the pathogen remains unclear. Here we show that in the country of Georgia, a known hotspot of MDR-TB, MDR Mycobacterium tuberculosis strains of lineage 4 (L4) transmit less than their drug-susceptible counterparts, whereas most MDR strains of L2 suffer no such defect. Our findings further indicate that the high transmission fitness of these L2 strains results from epistatic interactions between the rifampicin resistance-conferring mutation RpoB S450L, compensatory mutations in the RNA polymerase, and other pre-existing genetic features of L2/Beijing clones that circulate in Georgia. We conclude that the transmission fitness of MDR M. tuberculosis strains is heterogeneous, but can be as high as drug-susceptible forms, and that such highly drug-resistant and transmissible strains contribute to the emergence and maintenance of hotspots of MDR-TB. As these strains successfully overcome the metabolic burden of drug resistance, and given the ongoing rollout of new treatment regimens against MDR-TB, proper surveillance should be implemented to prevent these strains from acquiring resistance to the additional drugs.

Topics: Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Humans; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Humans; Isoniazid; Mycobacterium tuberculosis; Rifampin; Smoking; Treatment Outcome; Tuberculosis, Multidrug-Resistant

Tuberculosis (TB) is caused by Mycobacterium tuberculosis, still one of the most common life-threatening infectious diseases worldwide. Although drug resistance in M.tuberculosis is mainly due to spontaneous chromosomal mutations in genes encoding drug target or drug activating enzymes, the resistance cannot be explained only by these mutations. Low permeability of the cell wall, drug inactivating enzymes and especially efflux pumps (EPs) are other mechanisms of drug resistance in mycobacteria. Efflux pump inhibitors (EPIs) binding to M.tuberculosis EPs were shown to inhibit efflux of anti-TB drugs, to enhance M.tuberculosis killing, to reduce drug resistance and to produce synergistic effects with first line anti-TB drugs. In this study, we aimed to determine the minimum inhibitory concentration (MIC) of first-line anti-TB drugs in the presence of verapamil (VER) and the expression of 21 putative EP genes belonged to the ATP-binding cassette (ABC), major facilitator superfamily (MFS) and resistance-nodulation-division (RND) families which might have caused the resistance in nine M.tuberculosis complex clinical isolates resistant to all of the first line anti-TB drugs. MIC values of the isolates were determined in 96-well U-bottom plates by the resazurin microtiter test (REMA) method based on the color change principle. According to the determined MIC values of each isolate, freshly grown cultures in Middlebrook 7H9 broth were exposed to first-line anti-TB drugs and MIC of first-line anti-TB drugs in the presence of VER (½ MIC) at 37°C for 48 hours for RNA extraction. The non-drug exposed cultures were used as control. Total RNA was extracted using the RNeasy Mini Kit (Qiagen GmbH, Hilden, Germany) and then treated with DNase I (Thermo Fischer Scientific Inc., Waltham, MA). Complementary DNA (cDNA) from the extracted RNAs was synthesized with the "First strand cDNA synthesis kit" (Thermo Fischer Scientific Inc., Waltham, MA) using oligo primers. The expression levels of efflux pump genes by quantitative realtime polymerase chain reaction (qRt-PCR) were performed using the QuantiTect SYBR Green Rt-PCR Kit (Qiagen, Germany). The housekeeping sigma factor gene sigA (Rv2703) was used as internal control in qRt‑PCR assays. Relative quantification of the clinical isolates was determined by the 2-∆∆Ct method by comparing the expression levels of efflux genes in cultures exposed to primary anti-TB drugs and VER with those of non-drug exposed cultures. MIC values

Topics: Antitubercular Agents; Bacterial Proteins; DNA, Complementary; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant; Verapamil

The Xpert MTB/RIF (Xpert) assay has been widely used to diagnose suspected active tuberculosis (TB) and rifampicin-resistant TB cases. Despite its excellent performance record, false-positive Xpert rifampicin (RIF) resistance results are obtained for specimens with extremely low bacterial loads.. We aimed to study the feasibility of repeat Xpert testing as a strategy for reducing the odds of obtaining false-positive results when testing paucibacillary TB patients.. We enrolled previously tested TB patients with very low initial bacterial loads from May 2016 to February 2022 for Xpert retesting. A total of 251 TB patients were retested using the Xpert assay.. RIF resistance was noted in 65 (25.9 %) patients when tested by Xpert at initial diagnosis. Only 107 (42.6 %) of 251 patients tested positive for MTB when retested via Xpert. The majority (98.6 %) of RIF-susceptible cases were still susceptible to RIF when retested. Initial Xpert testing yielded 35 positive results for MTB in the RIF-resistant group, of whom 25 (71.4 %) still exhibited RIF resistance when retested. All culture-positive MTB isolates in the RIF-susceptible group were also RIF-susceptible by phenotypic DST. In the RIF-resistant group, 10 of 14 culture-positive MTB isolates exhibited RIF resistance, of which 4 isolates were deemed RIF-susceptible by phenotypic DST. The proportion of double mutations within the MTB rpoB RRDR sequence, as detected by hybridization of Xpert D and E probes, was significantly higher in the RIF-susceptible group than in the RIF-susceptible group.. Our results demonstrated that initial RIF-susceptible results were more accurate than RIF-resistant results. Additionally, patients with double mutations that delayed probe D/E hybridization were more likely to have false-positive Xpert results. Our findings emphasize that repeat Xpert MTB/RIF testing is necessary for TB patients with extremely low bacterial loads who are at high risk for RIF-resistant TB.

Topics: Antibiotics, Antitubercular; Bacterial Load; China; Drug Resistance, Bacterial; Humans; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

Isoniazid (INH) resistant Mycobacterium tuberculosis (Hr-TB) is the most common type of drug resistant TB, and is defined as M tuberculosis complex (MTBC) strains resistant to INH but susceptible to rifampicin (RIF). Resistance to INH precedes RIF resistance in almost all multidrug resistant TB (MDR-TB) cases, across all MTBC lineages and in all settings. Therefore, early detection of Hr-TB is critical to ensure rapid initiation of appropriate treatment, and to prevent progression to MDR-TB. We assessed the performance of the GenoType MTBDRplus VER 2.0 line probe assay (LPA) in detecting isoniazid resistance among MTBC clinical isolates.. A retrospective study was conducted among M. tuberculosis complex (MTBC) clinical isolates obtained from the third-round Ethiopian national drug resistance survey (DRS) conducted between August 2017 and December 2019. The sensitivity, specificity, positive predictive value, and negative predictive value of the GenoType MTBDRplus VER 2.0 LPA in detecting INH resistance were assessed and compared to phenotypic drug susceptibility testing (DST) using the Mycobacteria Growth Indicator Tube (MGIT) system. Fisher's exact test was performed to compare the performance of LPA between Hr-TB and MDR-TB isolates.. A total of 137 MTBC isolates were included, of those 62 were Hr-TB, 35 were MDR-TB and 40 were INH susceptible. The sensitivity of the GenoType MTBDRplus VER 2.0 for detecting INH resistance was 77.4% (95% CI: 65.5-86.2) among Hr-TB isolates and 94.3% (95% CI: 80.4-99.4) among MDR-TB isolates (P = 0.04). The specificity of the GenoType MTBDRplus VER 2.0 for detecting INH resistance was 100% (95% CI: 89.6-100). The katG 315 mutation was observed in 71% (n = 44) of Hr-TB phenotypes and 94.3% (n = 33) of MDR-TB phenotypes. Mutation at position-15 of the inhA promoter region alone was detected in four (6.5%) Hr-TB isolates, and concomitantly with katG 315 mutation in one (2.9%) MDR-TB isolate.. GenoType MTBDRplus VER 2.0 LPA demonstrated improved performance in detecting INH resistance among MDR-TB cases compared to Hr-TB cases. The katG315 mutation is the most common INH resistance conferring gene among Hr-TB and MDR-TB isolates. Additional INH resistance conferring mutations should be evaluated to improve the sensitivity of the GenoType MTBDRplus VER 2.0 for the detection of INH resistance among Hr-TB cases.

Topics: Antitubercular Agents; Ethiopia; Genotype; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant

There are scarce data on the incidence and resistance pattern of rifampicin-resistant Mycobacterium tuberculosis among kidney transplant recipients.. This is a retrospective, single- center study of kidney transplantrecipients suspected of M. tuberculosis infection. The GeneXpert assay we used detected mutations in the rpoB gene that confer rifampicin resistance using 5 overlapping probes (A, B, C, D, and E). The probes can detect mutations in the codons 507 to 511 (probe A), 511 to 518 (probe B), 518 to 523 (probe C), 523 to 529 (probe D), and 529 to 533 (probe E).We also detailed the treatment protocol and outcomes of kidney transplantrecipients infected with rifampicin-resistant M. tuberculosis.. In total, 2700 samples were processed during the period from October 2018 to February 2022 with successful results in 2640 samples (97.04%). One hundred and ninety (7.19%) samples were positive for M.tuberculosis, and rifampicin resistance was detected in 12 (0.45%) cases (11 pulmonary, 1 genitourinary). The most common rpoB mutation was located in the region of probe E (75.0%), followed by probe A (16.6%) and in 1 combination probe DE (8.33%). The rpoB mutations were not observed in probe B and probe C. Six patients received bedaquiline-based treatmentfor a short course of 11 months, whereas the other 6 patients required a long course of 18 to 20 months. Three patients died, 2 were lost to follow-up, and 7 were cured. During treatment, 4 patients experienced acute rejection, and 1 graft loss was reported.. We report for the first time the incidence and pattern of rifampicin resistance among kidney transplant recipients with tuberculosis infection. Further investigations are required for exploring the molecular and clinical phenotypes.

Topics: Drug Resistance, Bacterial; Humans; Kidney; Kidney Transplantation; Molecular Epidemiology; Mutation; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Drug Resistance, Bacterial; Humans; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Pyrazinamide; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Multidrug resistant (MDR) and extensively drug-resistant (XDR) tuberculosis (TB) are major public health threats that are significant causes of physical sequelae and financial consequences for infected people. Treatment for MDR- and XDR-TB are more toxic and take longer duration than for drug-susceptible-TB. As a result, the long-term sequelae are thought to be more common among patients with MDR- and XDR-TB than drug-susceptible-TB, but this is yet to be quantified. Hence, the aim of this systematic review and meta-analysis is to quantify the global burden and types of long-term physical sequelae and financial burden associated with both MDR- and XDR-TB.. We will search CINHAL, MEDLINE, Embase, Scopus, and Web of science for studies that report physical and financial sequelae associated with rifampicin-resistant (RR), MDR- and XDR-TB or their treatments. The search will be conducted without time, language, and place restrictions. A random-effects meta-analysis will be conducted to estimate the pooled prevalence of each physical sequela. Heterogeneity will be measured using the Higgins I2 statistics. We will assess publication bias visually using the funnel plot and statistically using Egger's test. Adjustments for publication basis will be made using Tweedie's and Duval Trim and Fill analysis.. Since the study is based on published evidence, ethics approval is not required. The findings of the systematic review will be presented at various conferences and will be published in a peer-reviewed journal.. The protocol is published in the PROSPERO with registration number CRD42021250909.

Topics: Antitubercular Agents; Extensively Drug-Resistant Tuberculosis; Financial Stress; Humans; Meta-Analysis as Topic; Rifampin; Risk Factors; Systematic Reviews as Topic; Tuberculosis, Multidrug-Resistant

To determine the effects of second-line anti-tuberculosis (TB) drugs on the composition and functions of intestinal microbiota in patients with rifampicin-resistant TB (RR-TB).. In this cross-sectional study, stool samples and relevant clinical information were collected from patients with RR-TB admitted to the Drug-resistant Specialty Department at Hunan Chest Hospital (Hunan Institute For Tuberculosis Control). The composition and functions of intestinal microbiota were analyzed using metagenomic sequencing and bioinformatics methods.. Altered structural composition of the intestinal microbiota was found when patients from the control, intensive phase treatment, and continuation phase treatment groups were compared (P<0.05). Second-line anti-TB treatment resulted in a decrease in the relative abundance of species, such as. Second-line anti-TB drug treatment caused changes in the structural composition of the intestinal microbiota in patients with RR-TB. In particular, this treatment induced a significant increase in the relative abundance of 11 conditionally pathogenic species, including

Topics: Antitubercular Agents; Cross-Sectional Studies; Gastrointestinal Microbiome; Humans; Mycobacterium tuberculosis; Rifampin; Tryptophan; Tuberculosis; Tuberculosis, Multidrug-Resistant

The development of tuberculosis and inflammatory status are closely related. The aim of this study was to investigate the prognostic value of inflammatory biomarkers in patients with rifampicin/multidrug-resistant tuberculosis (RR/MDR-TB).. This study recruited 504 patients with RR/MDR-TB from Wuhan Jinyintan Hospital. A total of 348 RR/MDR patients from January 2017 to December 2019 were defined as training set, the rest of patients as validation set. The patients were divided into three-risk degrees according to the levels of inflammatory biomarkers (median, 85th percentile). Kaplan-Meier curve and log-rank test were used to assess survival differences among the groups. Cox proportion risk regression was used to identify risk factors for RR/MDR-TB mortality.. In training set, cox proportion risk regression analysis showed that high age (≥60 years) [OR (95%CI):1.053(1.03188-1.077)], smoking [OR (95%CI):2.206(1.191-4.085)], and bronchiectasia [OR (95%CI):2.867(1.548-5.311)] were prognostic factors for RR/MDR-TB patients. In addition, lower survival rates were observed in high CAR group [OR (95%CI):1.464(1.275-1.681)], high CPR group[OR (95%CI):1.268(1.101-1.459)], high CLR group[OR (95%CI):1.004(1.002-1.005)], high NLR group[OR (95%CI):1.103(1.069-1.139)], high PLR group[OR (95%CI):1.003(1.002-1.004)], and high MLR group[OR (95%CI):3.471(2.188-5.508)].Furthermore, AUCs of age, smoking, bronchiectasia, CAR, CPR, CLR, NLR, PLR, and MLR for predicting mortality in RR/MDR-TB patients were 0.697(95%CI:0.618-0.775), 0.603(95%CI:0.512-0.695), 0.629(95%CI:0.538-0.721), 0.748(95%CI:0.675-0.821, P<0.05), 0.754(95%CI:0.683-0.824, P<0.05), 0.759(95%CI:0.689-0.828, P<0.05), 0.789(95%CI:0.731-0.846, P<0.05), 0.740(95%CI:0.669-0.812, P<0.05), and 0.752(95%CI:0.685-0.819, P<0.05), respectively. Importantly, the AUC of predicting mortality of combination of six inflammatory biomarkers [0.823 (95%CI:0.769-0.876)] is higher than any single inflammatory biomarkers. Additionally, the similar results are also obtained in the validation set.. Inflammatory biomarkers could predict the survival status of RR/MDR-TB patients. Therefore, more attention should be paid to the level of inflammatory biomarkers in clinical practice.

Topics: Antitubercular Agents; Biomarkers; Humans; Middle Aged; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Survival Analysis; Tuberculosis, Multidrug-Resistant

To address gaps in health services for multidrug- or rifampicin-resistant tuberculosis (MDR/RR-TB), a treatment cascade model was used to evaluate patient retention and attrition at each successive step required to achieve a successful treatment outcome.. From 2015-2018, a four-step treatment cascade model was established in patients with confirmed MDR/RR-TB in southeast China. Step 1: diagnosis of MDR/RR-TB, step 2: Initiation of treatment, step 3: still under treatment at 6 month and step 4: cure or completion of MDR/RR-TB treatment, with each successive step including a gap that shows attrition of patients between steps. The retention and attrition of each step were graphed. Multi-variate logistic regression was carried out to further identify potential factors associated with the attrition.. In the treatment cascade consisting of 1752 MDR/RR-TB patients, the overall patient attrition rate was 55.8% (978/1752), with 28.0% (491/1752), 19.9% (251/1261), and 23.4% (236/1010) of patients attrition in the first, second, and third gap. Factors associated with MDR/RR-TB patients not initiating treatment included age ≥60 years (OR:2.875), and time for diagnosis ≥30 days (OR: 2.653). Patients who were diagnosed with MDR/RR-TB through rapid molecular test (OR: 0.517) and non-migrant residents of Zhejiang Province (OR: 0.273) both exhibited a lower likelihood of attrition during the treatment initiation phase. Meanwhile, old age (OR: 2.190) and non-resident migrants to the province were factors associated with not completing ≥ 6 months of treatment. Old age (OR: 3.883), retreatment (OR: 1.440), and time to diagnosis ≥30 days (OR: 1.626) were factors contributing to poor treatment outcomes.. Several programmatic gaps were identified in the MDR/RR-TB treatment cascade. Future policies should provide more comprehensive support for vulnerable populations to improve the care quality at each step.

Topics: Antitubercular Agents; China; Humans; Infant; Middle Aged; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant

Toxin-antitoxin systems (TAs) are highly conserved in Mycobacterium tuberculosis (Mtb). The TAs role in maintaining and disseminating drug resistance in bacterial populations has been indicated. So, we aimed to analyze the expression level of mazEF-related genes in drugsusceptible and multidrug-resistant (MDR) Mtb isolates under isoniazid (INH) and rifampin (RIF) stress.. We obtained 23 Mtb isolates, including 18 MDR and 5 susceptible isolates, from the Ahvaz Regional TB Laboratory collection. The expression levels of mazF3, mazF6, and mazF9 toxin genes, and mazE3, mazE6, and mazE9 antitoxin genes in MDR and susceptible isolates were evaluated by quantitative real-time PCR (qRT-PCR) after exposure to RIF and INH.. The mazF3, F6, and F9 toxin genes were overexpressed in at least two MDR isolates in the presence of RIF and INH, in contrast to mazE antitoxin genes. More MDR isolates were induced to overexpress mazF genes by RIF than INH (72.2% vs. 50%). Compared to the H37Rv strain and susceptible isolates, the expression levels of mazF3,6 by RIF and mazF3,6,9 by INH were significantly upregulated in MDR isolates (p<0.05), but no remarkable difference was detected in the expression level of mazF9 genes by INH between these groups. In susceptible isolates, the expression levels of mazE3,6 by RIF and mazE3,6,9 by INH were induced and enhanced significantly compared to MDR isolates, but there was no difference between MDR and H37Rv strain.. Based on the results, we propose that mazF expression under RIF/INH stress may be associated with drug resistance in Mtb in addition to mutations, and the mazE antitoxins may be related to enhanced susceptibility of Mtb to INH and RIF. Further experiments are needed to investigate the exact mechanism underlying the TA system's role in drug resistance.

Topics: Antitoxins; Antitubercular Agents; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Tuberculosis infection (TBI) and TB disease (TBD) incidence remains poorly described following household contact (HHC) rifampin-/multidrug-resistant TB exposure. We sought to characterize TBI and TBD incidence at 1 year in HHCs and to evaluate TB preventive treatment (TPT) use in high-risk groups.. We previously conducted a cross-sectional study of HHCs with rifampin-/multidrug-resistant TB in 8 high-burden countries and reassessed TBI (interferon-gamma release assay, HHCs aged ≥5 years) and TBD (HHCs all ages) at 1 year. Incidence was estimated across age and risk groups (<5 years; ≥5 years, diagnosed with human immunodeficiency virus [HIV]; ≥5 years, not diagnosed with HIV/unknown, baseline TBI-positive) by logistic or log-binomial regression fitted using generalized estimating equations.. Of 1016 HHCs, 850 (83.7%) from 247 households were assessed (median, 51.4 weeks). Among 242 HHCs, 52 tested interferon-gamma release assay-positive, yielding a 1-year 21.6% (95% confidence interval [CI], 16.7-27.4) TBI cumulative incidence. Sixteen of 742 HHCs developed confirmed (n = 5), probable (n = 3), or possible (n = 8) TBD, yielding a 2.3% (95% CI, 1.4-3.8) 1-year cumulative incidence (1.1%; 95% CI, .5-2.2 for confirmed/probable TBD). TBD relative risk was 11.5-fold (95% CI, 1.7-78.7), 10.4-fold (95% CI, 2.4-45.6), and 2.9-fold (95% CI, .5-17.8) higher in age <5 years, diagnosed with HIV, and baseline TBI high-risk groups, respectively, vs the not high-risk group (P = .0015). By 1 year, 4% (21 of 553) of high-risk HHCs had received TPT.. TBI and TBD incidence continued through 1 year in rifampin-/multidrug-resistant TB HHCs. Low TPT coverage emphasizes the need for evidence-based prevention and scale-up, particularly among high-risk groups.

Topics: Cross-Sectional Studies; HIV Infections; Humans; Incidence; Latent Tuberculosis; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Topics: Antibiotics, Antitubercular; Antitubercular Agents; Child; Drug Resistance, Bacterial; Humans; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Rifampin-resistant tuberculosis is a leading cause of morbidity worldwide; only one-third of persons start treatment, and outcomes are often inadequate. Several trials demonstrate 90% efficacy using an all-oral, 6-month regimen of bedaquiline, pretomanid, and linezolid (BPaL), but significant toxicity occurred using 1200-mg linezolid. After US Food and Drug Administration approval in 2019, some US clinicians rapidly implemented BPaL using an initial 600-mg linezolid dose adjusted by serum drug concentrations and clinical monitoring.. Data from US patients treated with BPaL between 14 October 2019 and 30 April 2022 were compiled and analyzed by the BPaL Implementation Group (BIG), including baseline examination and laboratory, electrocardiographic, and clinical monitoring throughout treatment and follow-up. Linezolid dosing and clinical management was provider driven, and most patients had linezolid adjusted by therapeutic drug monitoring.. Of 70 patients starting BPaL, 2 changed to rifampin-based therapy, 68 (97.1%) completed BPaL, and 2 of the 68 (2.9%) experienced relapse after completion. Using an initial 600-mg linezolid dose daily adjusted by therapeutic drug monitoring and careful clinical and laboratory monitoring for adverse effects, supportive care, and expert consultation throughout BPaL treatment, 3 patients (4.4%) with hematologic toxicity and 4 (5.9%) with neurotoxicity required a change in linezolid dose or frequency. The median BPaL duration was 6 months.. BPaL has transformed treatment for rifampin-resistant or intolerant tuberculosis. In this cohort, effective treatment required less than half the duration recommended in 2019 US guidelines for drug-resistant tuberculosis. Use of individualized linezolid dosing and monitoring likely enhanced safety and treatment completion. The BIG cohort demonstrates that early implementation of new tuberculosis treatments in the United States is feasible.

Topics: Antitubercular Agents; Diarylquinolines; Humans; Linezolid; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant; United States

The Xpert MTB/XDR assay met the critical need for etiologic diagnosis of tuberculosis and rifampin resistance in previous studies. However, its benefits in tailoring the treatment regimen and improving the outcome for patients with rifampin-resistant tuberculosis (RR-TB) require further investigation. In this study, the Xpert MTB/XDR assay was used to determine the resistance profile of second-line drugs for RR-TB patients in two registered multicenter clinical trials, TB-TRUST (NCT03867136) and TB-TRUST-plus (NCT04717908), with the aim of testing the efficacy of all-oral shorter regimens in RR-TB patients in China. Patients would receive the fluoroquinolone-based all-oral shorter regimen, the injectable-containing regimen, or the bedaquiline-based regimen depending on fluoroquinolone susceptibility by using Xpert MTB/XDR. Among the 497 patients performed with Xpert MTB/XDR, 128 (25.8%) had infections resistant to fluoroquinolones and/or second-line injectable drugs (SLIDs). A total of 371 participants were recruited for the trials, and whole-genome sequencing (WGS) was performed on all corresponding culture-positive baseline strains. Taking the WGS results as the standard, the accuracy of the Xpert MTB/XDR assay in terms of resistance detection was 95.2% to 99.0% for all drugs. A total of 33 cases had inconsistent results, 9 of which were due to resistance heterogeneity. Most of the patients (241/281, 85.8%) had sputum culture conversion at 2 months. In conclusion, the Xpert MTB/XDR assay has the potential to serve as a quick reflex test in patients with RR-TB, as detected via Xpert MTB/RIF, to provide a reliable drug susceptibility profile of the infecting Mycobacterium tuberculosis strain and to initiate optimized treatment promptly.

Topics: Antibiotics, Antitubercular; Drug Resistance, Bacterial; Fluoroquinolones; Humans; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis; Tuberculosis, Multidrug-Resistant

Experimental data show that drug-resistance-conferring mutations are often associated with a decrease in the replicative fitness of bacteria in vitro, and that this fitness cost can be mitigated by compensatory mutations; however, the role of compensatory evolution in clinical settings is less clear. We assessed whether compensatory evolution was associated with increased transmission of rifampicin-resistant tuberculosis in Khayelitsha, Cape Town, South Africa.. We did a genomic epidemiological study by analysing available M tuberculosis isolates and their associated clinical data from individuals routinely diagnosed with rifampicin-resistant tuberculosis in primary care and hospitals in Khayelitsha, Cape Town, South Africa. Isolates were collected as part of a previous study. All individuals diagnosed with rifampicin-resistant tuberculosis and with linked biobanked specimens were included in this study. We applied whole-genome sequencing, Bayesian reconstruction of transmission trees, and phylogenetic multivariable regression analysis to identify individual and bacterial factors associated with the transmission of rifampicin-resistant M tuberculosis strains.. Between Jan 1, 2008, and Dec 31, 2017, 2161 individuals were diagnosed with multidrug-resistant or rifampicin-resistant tuberculosis in Khayelitsha, Cape Town, South Africa. Whole-genome sequences were available for 1168 (54%) unique individual M tuberculosis isolates. Compensatory evolution was associated with smear-positive pulmonary disease (adjusted odds ratio 1·49, 95% CI 1·08-2·06) and a higher number of drug-resistance-conferring mutations (incidence rate ratio 1·38, 95% CI 1·28-1·48). Compensatory evolution was also associated with increased transmission of rifampicin-resistant disease between individuals (adjusted odds ratio 1·55; 95% CI 1·13-2·12), independent of other patient and bacterial factors.. Our findings suggest that compensatory evolution enhances the in vivo fitness of drug-resistant M tuberculosis genotypes, both within and between patients, and that the in vitro replicative fitness of rifampicin-resistant M tuberculosis measured in the laboratory correlates with the bacterial fitness measured in clinical settings. These results emphasise the importance of enhancing surveillance and monitoring efforts to prevent the emergence of highly transmissible clones capable of rapidly accumulating new drug resistance mutations. This concern becomes especially crucial at present, because treatment regimens incorporating novel drugs are being implemented.. Funding for this study was provided by a Swiss and South Africa joint research award (grant numbers 310030_188888, CRSII5_177163, and IZLSZ3_170834), the European Research Council (grant number 883582), and a Wellcome Trust fellowship (to HC; reference number 099818/Z/12/Z). ZS-D was funded through a PhD scholarship from the South African National Research Foundation and RMW was funded through the South African Medical Research Council.

Topics: Bayes Theorem; Genomics; Humans; Mycobacterium tuberculosis; Phylogeny; Rifampin; South Africa; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Stenotrophomonas maltophilia; Tuberculosis; Tuberculosis, Multidrug-Resistant

Rifampicin-resistant tuberculosis (RR-TB) involves treatment with many drugs that can prolong the QT interval; this risk may increase when multiple QT-prolonging drugs are used together. We assessed QT interval prolongation in children with RR-TB receiving one or more QT-prolonging drugs. Data were obtained from two prospective observational studies in Cape Town, South Africa. Electrocardiograms were performed before and after drug administration of clofazimine (CFZ), levofloxacin (LFX), moxifloxacin (MFX), bedaquiline (BDQ), and delamanid. The change in Fridericia-corrected QT (QTcF) was modeled. Drug and other covariate effects were quantified. A total of 88 children with a median (2.5th-to-97.5th range) age of 3.9 (0.5 to 15.7) years were included, of whom 55 (62.5%) were under 5 years of age. A QTcF interval of >450 ms was observed in 7 patient-visits: regimens were CFZ+MFX (

Topics: Adolescent; Antitubercular Agents; Child; Child, Preschool; Clofazimine; Electrocardiography; Humans; Levofloxacin; Rifampin; South Africa; Tuberculosis, Multidrug-Resistant

The purpose of this study was to determine the diagnostic efficacy of Xpert MTB/RIF assay for rapid diagnosis of Tuberculosis (TB) and detection of rifampicin (RIF) resistance in patients suspected of having EPTB, assessing it against traditional culture and drug susceptibility test (DST) by proportional method, and the ability to predict multidrug resistance TB by Xpert MTB/RIF assay. In this study, the Xpert MTB/RIF assay was applied to 1,614 extrapulmonary specimens. Compared with TB culture and Composite Reference Standard (CRS), the Xpert MTB/RIF assay had a high sensitivity and specificity for detection of EPTB. Depending on the culture method or CRS as the standard, sensitivity of the Xpert MTB/RIF assay for detection of MTB in pleural effusion, cerebrospinal fluid, thoracic drainage fluid and throat swabs specimens were lower than that of other specimens. According to the experimental results, we have reason to believe that Xpert MTB/RIF assay is a rapid and simple technique with high sensitivity and specificity for diagnosing EPTB and detecting drug resistance in variety of specimens. Xpert MTB/RIF assay combined with DST maybe identify more cases of multi-drug resistant tuberculosis (MDR-TB).

Topics: Antibiotics, Antitubercular; Drug Resistance, Bacterial; Humans; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis; Tuberculosis, Extrapulmonary; Tuberculosis, Multidrug-Resistant

To investigate the performance of GeneXpert MTB/RIF Ultra to accurately detect rifampicin resistance for less common rpoB mutations that potentially confer phenotypic resistance, we tested 28 such Mycobacterium tuberculosis cultures with Xpert Ultra.. They represented 22 different (combinations of) rpoB mutations. Of 28 isolates tested, one was reported by Xpert Ultra as "No rifampicin resistance detected", 8 yielded a "Rifampicin indeterminate" result, and 19 were identified as rifampicin resistant. Overall, our results corroborate previous observations on the "Indeterminate" results for mutations at codon 432, while we add Lys446Gln as additional "Indeterminate" result and Pro439Leu as a false rifampicin-susceptible result. Furthermore, we document other uncommon point mutations and indels across the rpoB gene that are mostly correctly identified as rifampicin resistant by Xpert ultra (V3). Taken together, "Indeterminate" results in Xpert Ultra may indicate underlying rpoB mutations within the rifampicin-resistance determining region and thus increase the post-test probability of rifampicin resistance, albeit to an unknown extent.

Topics: Antibiotics, Antitubercular; Drug Resistance, Bacterial; Humans; Mutation; Mycobacterium tuberculosis; Point Mutation; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

Tuberculosis causes serious mortality and morbidity worldwide each year. A lot of effort and money is spent for the diagnosis and treatment of tuberculosis all over the world. The importance that countries give to health policies and public health is inversely proportional to the incidence of tuberculosis and multidrug resistant tuberculosis. The aim of our study was to evaluate the resistance profiles of Mycobacterium tuberculosis complex strains which were isolated from sputum samples, collected by World Health Organisation from patients living in the northern region of Syria, where health services were disrupted due to the civil war. According to the protocol signed between the World Health Organization and our hospital; sputum samples taken from tuberculosis patients living in Afrin, Azez and Idlib regions or suspected of being resistant to anti-tuberculosis drugs were studied in our hospital. The cultivation process was performed in our laboratory using Löwenstein Jensen media and MGIT-960 system. The susceptibility tests for primary anti-tuberculosis drugs were performed using MGIT-960 system for M.tuberculosis complex isolates. The isolates identified as MDR/RD-TB (multi-drug-resistant-rifampicin-resistant tuberculosis) were sent to National Tuberculosis Reference Laboratory of Public Health Institution of Türkiye for susceptibility testing to first and second line drugs. Mutation and wild-type determination were studied by "Line Probe Assay (LPA)" method to investigate the susceptibility of the isolates to isoniazid, rifampicin, fluoroquinolone and aminoglycoside/cyclic peptide. The results obtained from the patients were collected and evaluated retrospectively from the records. Growth was observed in 18 samples out of 171 sputum samples from 67 patients; 13 isolates were detected as MDR-TB while one isolate was detected as mono RR-TB. The rate of mono RR-TB was 1.5% and the rate of MDR-TB was 19.4%. MUT3 causing rifampicin resistance was detected in 17.9% of the patients, katG/MUT1 causing isoniazid resistance in 17.9% and WT loss causing aminoglycoside/cyclic peptide resistance were detected in 19.4% of the patients. Neither fluoroquinolone resistance nor a mutation leading to fluoroquinolone resistance was detected in the study. When the sputum samples taken from the patients living in Northern Syria were examined, the frequency of MDR-TB was found to be quite high. MDR-TB, which is an important public health problem, was found at high rates du

Topics: Aminoglycosides; Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Fluoroquinolones; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Syria; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Diarylquinolines; HIV Infections; HIV Seropositivity; Humans; Linezolid; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant; World Health Organization

The patient had received five courses of anti-tuberculosis treatment for recurrent tuberculosis. The drug sensitivity test results of the first three courses showed drug-sensitive pulmonary tuberculosis, and the fourth diagnosis was rifampin-resistant tuberculosis (RR-TB), complicated by chronic obstructive pulmonary disease, type Ⅱ respiratory failure, pulmonary heart disease, and heart failure (grade Ⅲ). The patient stopped taking the anti-tuberculosis drugs on his own in the eighth month of receiving the resistant treatment. After admission, the symptoms improved temporarily after receiving oxygen therapy, anti-infection, and anti-tuberculosis treatment. Because of hemoptysis, the patient underwent arterial embolization by catheterization, but a large amount of hemoptysis occurred shortly thereafter. Emergency left total lung resection and gauze packing for hemostasis were performed. After surgery, the patient's vital signs were maintained with mechanical ventilation and vasopressors. Forty-eight hours after surgery, the gauze was removed, and the patient underwent tracheotomy, enteral nutrition, and anti-tuberculosis treatment. After discharge, the patient underwent rehabilitative exercise and anti-resistant tuberculosis therapy. The patient's condition remained stable for more than six months of follow-up.. 本例患者因肺结核经历5次抗结核治疗，前3次药物敏感试验均显示为非耐药肺结核，第4次诊断为利福平耐药结核病（rifampin-resistant tuberculosis，RR-TB），合并慢性阻塞性肺疾病、Ⅱ型呼吸衰竭、肺源性心脏病及心功能不全（Ⅲ级），按照耐药结核病治疗方案8个月后患者自行停药。此次因咳喘、胸闷入院，经吸氧、抗感染、抗结核治疗后症状缓解，因咯血行经导管动脉栓塞术治疗，术后再发大咯血，急诊行胸膜外左全肺切除+胸腔纱布填塞止血术，术后呼吸机、血管活性药物维持生命体征，48 h后拔出纱布并气管切开、鼻饲营养、抗结核等治疗，出院后康复锻炼、口服耐药方案治疗，随访半年余病情平稳。.

Topics: Antitubercular Agents; Hemoptysis; Humans; Lung; Rifampin; Thoracic Diseases; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

GeneXpert MTB/RIF (Mycobacterium tuberculosis/rifampicin) assay is a method for detecting rifampicin resistance (RR-MTB) in suspected samples in less than 2 hours with high sensitivity and specificity yield. This study aimed to use the GeneXpert MTB/RIF assay to determine the frequency of RR-MTB and to study the possible influencing correlates associated with positive results.. This is a retrospective cross-sectional study of patients who visited TB clinic in 5 years (2016-2021). According to the data sheet of the patients, all the collected specimens were divided into 2 parts one for diagnosis by Ziehl-Neelsen stain and the other part for GeneXpert analysis. GeneXpert was also used to look for evidence of RR.. Out of the 2605 total samples screened, 718 (27.6%) tested positive for MTB on GeneXpert assay; of them 633 (88.4%) were sensitive to Rifampicin, 83 (11.6%) were resistant to Rifampicin and 2 cases were undetermined. Factors contributing to RR-MTB were: smoker/ex-smoker, with 2.5 times more risk (p = 0.013.0, p = 0.001); recurrence cases had a 4-fold increased risk (p < 0.001); patients with very low M. tuberculosis detected on the GeneXpert MTB/RIF test were 8 times more likely to have RR-TB (P = 0.004).. This study disclosed a high-rate MTB in Egyptian probable TB cases. Smoking, recurrence and cases with a very low M. tuberculosis burden noticed on the GeneXpert MTB/RIF test had augmented risk of RR-TB.

Topics: Cross-Sectional Studies; Egypt; Humans; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Sensitivity and Specificity; Tuberculosis; Tuberculosis, Multidrug-Resistant

In recent years, nucleic-acid amplification tests (NAATs), which are highly specific and sensitive, have helped to transform the TB diagnostic landscape. According to the WHO 2021 Guidelines on Diagnostics, the NAATs used in TB diagnosis at the point of care (POC) include Xpert MTB/RIF a cartridge-based test manufactured by Cepheid, and Truenat a chip-based test manufactured by Molbio. Other POC tests that are expected to be implemented in near future include Xpert Omni and Xpert MTB/XDR. The use of line probe assay is involved at the level of reference labs for the detection of MTB and its resistance to first-line (Isoniazid and Rifampicin) and second-line (fluoroquinolones and second-line injectables) drugs. When the currently available NAATs detect mutations for drug resistance at a particular region of MTB sequence, the Whole genome sequencing (WGS) platform demonstrates the exceptional potential for reliable and comprehensive resistance prediction for MTB isolates, by multiple gene regions or whole genome sequence analysis allowing for accurate clinical decisions.

Topics: Antibiotics, Antitubercular; Drug Resistance, Bacterial; Humans; Isoniazid; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis; Tuberculosis, Multidrug-Resistant

This study aimed to determinate characteristics of drug resistance

Topics: Drug Resistance; Humans; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Tuberculosis, Extrapulmonary; Tuberculosis, Multidrug-Resistant; Whole Genome Sequencing

Meropenem in combination with β-lactamase inhibitors (BLIs) and other drugs was tested to identify alternative treatment regimens for multidrug-resistant tuberculosis (MDR-TB).. The following were performed: (1) MIC experiments; (2) static time-kill studies (STKs) with different BLIs; and (3) a hollow fibre model system of TB (HFS-TB) studies with meropenem-vaborbactam combined with human equivalent daily doses of 20 mg/kg or 35 mg/kg rifampin, or moxifloxacin 400 mg, or linezolid 600 mg vs. bedaquiline-pretonamid-linezolid (BPaL) for MDR-TB. The studies were performed using Mycobacterium tuberculosis (M. tuberculosis) H37Rv and an MDR-TB clinical strain (named M. tuberculosis 16D) that underwent whole genome sequencing. Exponential decline models were used to calculate the kill rate constant (K) of different HFS-TB regimens.. Adding meropenem-vaborbactam could potentially restore the efficacy of isoniazid and rifampin against MDR-TB. The meropenem-vaborbactam-moxifloxacin backbone regimen has implications for creating a new effective MDR-TB regimen.

Topics: Antitubercular Agents; beta-Lactamase Inhibitors; Humans; Isoniazid; Linezolid; Meropenem; Moxifloxacin; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Mycobacterium tuberculosis complex has an impact on public health and is responsible for over one million deaths per year. Substantial numbers of people infected with M. tuberculosis can develop tuberculosis lymphadenitis; however, there is a limited study in Adama, Ethiopia. The aim of this study was to determine the magnitude of Tuberculosis lymphadenitis, its predictors, and rifampicin-resistance gene-positive M. tuberculosis. A total of 291 patients with enlarged lymph nodes were recruited from May 2022 to August 30 at Adama Comprehensive Specialized Hospital Medical College (ACSHMC). GeneXpert, Ziehl-Neelsen staining, and cytology were used for the diagnosis of TB lymphadenitis from the Fine Needle Aspirate (FNA) specimen. Rifampicin-resistant gene was detected using GeneXpert. For data entry and analysis, Epi Data version 3.0 and SPSS version 25 were used respectively. A binary logistic regression model was used to identify predictors of TB lymphadenitis. A p < 0.05 with a 95% confidence interval (CI) was taken as a cut point to determine the significant association between dependent and independent variables. The prevalence of TB lymphadenitis using GeneXpert, Ziehl-Neelsen staining, and cytology were 138 (47.4%) (95% CI 41.70-53.10), 100 (34.4%) (95% CI 28.94-39.85), and 123 (42.3%) (95% CI 36.63-47.00) respectively. Nine (3.1%) participants were infected with rifampicin-resistant gene-positive M. tuberculosis. Out of the total M. tuberculosis detected by GeneXpert (n = 138), 9 (6.5%) were positive for rifampicin resistance-gene. Participants with a chronic cough had 2 times odds of developing TB lymphadenitis (AOR: 2.001, 95% CI 1.142-3.508). Close to half of patients with enlarged lymph nodes were positive for M. tuberculosis by the GeneXpert method in the study area. Chronic cough was significantly associated with TB lymphadenitis. Rifampicin-resistant gene-positive M. tuberculosis was relatively prevalent among patients with enlarged lymph node in the study area.

Topics: Cough; Cross-Sectional Studies; Ethiopia; Humans; Lymphadenitis; Mycobacterium tuberculosis; Rifampin; Risk Factors; Tuberculosis, Lymph Node; Tuberculosis, Multidrug-Resistant

Topics: Humans; Mycobacterium tuberculosis; Point-of-Care Testing; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant

The spread of multidrug-resistant tuberculosis (MDR-TB) is a growing problem in many countries worldwide. Resistance to one of the primary first-line drugs, rifampicin, is caused by mutations in the

Topics: Bacterial Proteins; Bangladesh; Humans; Mutation; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Multidrug-resistant tuberculosis (MDR-TB) remains a major public health problem in many high tuberculosis (TB) burden countries. Phenotypic drug susceptibility testing (DST) take several weeks or months to result, but line probe assays and Xpert/Rif Ultra assay detect a limited number of resistance conferring gene mutations. Whole genome sequencing (WGS) is an advanced molecular testing method which theoretically can predict the resistance of M. tuberculosis (Mtb) isolates to all anti-TB agents through a single analysis.. Here, we aimed to identify the level of concordance between the phenotypic and WGS-based genotypic drug susceptibility (DS) patterns of MDR-TB isolates. Overall, data for 12 anti-TB medications were analyzed.. In total, 63 MDR-TB Mtb isolates were included in the analysis, representing 27.4% of the total number of MDR-TB cases in Latvia in 2012-2014. Among them, five different sublineages were detected, and 2.2.1 (Beijing group) and 4.3.3 (Latin American-Mediterranean group) were the most abundant. There were 100% agreement between phenotypic and genotypic DS pattern for isoniazid, rifampicin, and linezolid. High concordance rate (> 90%) between phenotypic and genotypic DST results was detected for ofloxacin (93.7%), pyrazinamide (93.7%) and streptomycin (95.4%). Phenotypic and genotypic DS patterns were poorly correlated for ethionamide (agreement 56.4%), ethambutol (85.7%), amikacin (82.5%), capreomycin (81.0%), kanamycin (85.4%), and moxifloxacin (77.8%). For capreomycin, resistance conferring mutations were not identified in several phenotypically resistant isolates, and, in contrary, for ethionamide, ethambutol, amikacin, kanamycin, and moxifloxacin the resistance-related mutations were identified in several phenotypically sensitive isolates.. WGS is a valuable tool for rapid genotypic DST for all anti-TB agents. For isoniazid and rifampicin phenotypic DST potentially can be replaced by genotypic DST based on 100% agreement between the tests. However, discrepant results for other anti-TB agents limit their prescription based solely on WGS data. For clinical decision, at the current level of knowledge, there is a need for combination of genotypic DST with modern, validated phenotypic DST methodologies for those medications which did not showed 100% agreement between the methods.

Topics: Amikacin; Antitubercular Agents; Capreomycin; Drug Resistance, Multiple, Bacterial; Ethambutol; Ethionamide; Humans; Isoniazid; Kanamycin; Latvia; Microbial Sensitivity Tests; Moxifloxacin; Mycobacterium tuberculosis; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant; Whole Genome Sequencing

In 2020, almost half a million individuals developed rifampicin-resistant tuberculosis (RR-TB). We estimated the global burden of RR-TB over the lifetime of affected individuals. We synthesized data on incidence, case detection, and treatment outcomes in 192 countries (99.99% of global tuberculosis). Using a mathematical model, we projected disability-adjusted life years (DALYs) over the lifetime for individuals developing tuberculosis in 2020 stratified by country, age, sex, HIV, and rifampicin resistance. Here we show that incident RR-TB in 2020 was responsible for an estimated 6.9 (95% uncertainty interval: 5.5, 8.5) million DALYs, 44% (31, 54) of which accrued among TB survivors. We estimated an average of 17 (14, 21) DALYs per person developing RR-TB, 34% (12, 56) greater than for rifampicin-susceptible tuberculosis. RR-TB burden per 100,000 was highest in former Soviet Union countries and southern African countries. While RR-TB causes substantial short-term morbidity and mortality, nearly half of the overall disease burden of RR-TB accrues among tuberculosis survivors. The substantial long-term health impacts among those surviving RR-TB disease suggest the need for improved post-treatment care and further justify increased health expenditures to prevent RR-TB transmission.

Topics: Antitubercular Agents; Global Burden of Disease; Humans; Models, Theoretical; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Bacterial Proteins; Drug Resistance, Multiple, Bacterial; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

GeneXpert MTB/RIF, a tool widely used for diagnosing tuberculosis, has limitations for detecting rifampin resistance in certain variants. We report transmission of a pre-extensively drug-resistant variant in Botswana that went undetected by GeneXpert. The public health impact of misdiagnosis emphasizes the need for comprehensive molecular testing to identify resistance and guide treatment.

Topics: Antibiotics, Antitubercular; Botswana; Drug Resistance, Bacterial; Humans; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis; Tuberculosis, Multidrug-Resistant

Tuberculosis stands as a prominent cause of mortality in developing countries. The treatment of tuberculosis involves a complex procedure requiring the administration of a panel of at least four antimicrobial drugs for the duration of six months. The occurrence of treatment failure after the completion of a standard treatment course presents a serious medical problem. The purpose of this study was to evaluate antimicrobial drug resistant features of Mycobacterium tuberculosis associated with treatment failure. Additionally, it aimed to evaluate the effectiveness of second line drugs such as amikacin, linezolid, moxifloxacin, and the efflux pump inhibitor verapamil against M. tuberculosis isolates associated with treatment failure. We monitored 1200 tuberculosis patients who visited TB centres in Lahore and found that 64 of them were not cured after six months of treatment. Among the M. tuberculosis isolates recovered from the sputum of these 64 patients, 46 (71.9%) isolates were simultaneously resistant to rifampicin and isoniazid (MDR), and 30 (46.9%) isolates were resistant to pyrazinamide, Resistance to amikacin was detected in 17 (26,5%) isolates whereas resistance to moxifloxacin and linezolid was detected in 1 (1.5%) and 2 (3.1%) isolates respectively. Among MDR isolates, the additional resistance to pyrazinamide, amikacin, and linezolid was detected in 15(23.4%), 4(2.6%) and 1(1.56%) isolates respectively. One isolate simultaneously resistant to rifampicin, isoniazid, amikacin, pyrazinamide, and linezolid was also identified. In our investigations, the most frequently mutated amino acid in the treatment failure group was Serine 315 in katG. Three novel mutations were detected at codons 99, 149 and 154 in pncA which were associated with pyrazinamide resistance. The effect of verapamil on the minimum inhibitory concentration of isoniazid and rifampicin was observed in drug susceptible isolates but not in drug resistant isolates. Rifampicin and isoniazid enhanced the transcription of the efflux pump gene rv1258 in drug susceptible isolates collected from the treatment failure patients. Our findings emphasize a high prevalence of MDR isolates linked primarily to drug exposure. Moreover, the use of amikacin as a second line drug may not be the most suitable choice in such cases.

Topics: Amikacin; Antitubercular Agents; Humans; Isoniazid; Linezolid; Microbial Sensitivity Tests; Moxifloxacin; Mutation; Mycobacterium tuberculosis; Pyrazinamide; Rifampin; Tuberculosis, Multidrug-Resistant; Verapamil

Topics: Antitubercular Agents; Drug Resistance, Bacterial; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

There were no data about prevention and control status of RR-TB in a poor area with high burden of TB in China. In order to develop evidence-based RR-TB response strategies and improve enrollment of RR-TB patients in Yunnan province, China, this study was aimed at analyzing the changing trends in the detection and enrollment of RR-TB patients and examining the factors that may have implication on enrollment in treatment.. Data, which includes demographics, screening and testing, and treatment enrollment, was collected from the TB Management Information System. Retrospective data analysis and factors analysis were applied. Descriptive statistics, Chi-square test, Rank sum test and logistic regression analysis were used.. From 2016 and 2018, the province had been challenged by low levels of screening, detection and enrollment of RR-TB. During the period between 2019 and 2020, a comprehensive model of RR-TB prevention and control was established in Yunnan, characterized by a robust patient-centered approach for RR-TB care and multiple, targeted interventions through the cascade of care from detection to treatment. In 2020, 93.8% of the bacteriologically positive TB patients were screened for RR-TB, which had been significantly increased by 146.9% from 38.0% in 2016. The interval from initial consultation at RR-TB facility to diagnosis (inter-quartile range) was reduced from 29.5 (1-118) days in 2016 to 0 (0-7) days in 2020. Despite the increasing rates of enrollment of RR-TB patients over the years, non-enrollment of those detected was still high (32.3%) in 2020. The main reasons for non-enrollment identified were refusal of treatment due to financial difficulties, loss to follow-up or death before starting treatment. Multivariate analysis showed that the elderly patients aged 65 or above (OR = 2.7, CI: 1.997-3.614), new patients (OR = 0.7, CI: 0.607-0.867), conventional DST used for confirmatory diagnosis of RR-TB (OR = 1.9, CI: 1.620-2.344) and diagnosis of RR-TB being conducted by the RR-TB care facilities at the prefecture and municipal level (OR = 4.4, CI: 3.608-5.250) have implications on RR-TB non-enrollment.. As a comprehensive RR-TB model was implemented in Yunnan with scaled up use of molecular test for rapid detection of RR-TB, initial screening of RR-TB were decentralized to the county- and district-level to strengthen rapid, early detection of RR-TB, achieving a higher coverage of screening in the end. However, there remains a major gap in enrollment of RR-TB. The main barriers include: limited knowledge and awareness of RR-TB and financial burdens among patients, delayed diagnosis, loss to follow-up, difficulties in self care and travel for elderly patients, and limited capacity of clinical management at the lower-level RR-TB care facilities. The situation of the RR-TB epidemic in Yunnan could be improved and contained as soon as possible by continuous strengthening of the comprehensive, patient-centered model with targeted interventions coordinated through multi-sectoral engagement to improve enrollment of RR-TB patients.

Topics: Aged; China; Early Diagnosis; Humans; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant

Treatment for multidrug-resistant/rifampicin-resistant tuberculosis (MDR/RR-TB) is increasingly transitioning from hospital-centred to community-based care. A national policy for decentralised programmatic MDR/RR-TB care was adopted in South Africa in 2011. We explored variations in the implementation of care models in response to this change in policy, and the implications of these variations for people affected by MDR/RR-TB.. A mixed methods study was done of patient movements between healthcare facilities, reconstructed from laboratory records. Facility visits and staff interviews were used to determine reasons for movements.. People identified with MDR/RR-TB from 13 high-burden districts within South Africa.. Geospatial movement patterns were used to identify organisational models. Reasons for patient movement and implications of different organisational models for people affected by MDR/RR-TB and the health system were determined.. Among 191 participants, six dominant geospatial movement patterns were identified, which varied in average hospital stay (0-281 days), average patient distance travelled (12-198 km) and number of health facilities involved in care (1-5 facilities). More centralised models were associated with longer delays to treatment initiation and lengthy hospitalisation. Decentralised models facilitated family-centred care and were associated with reduced time to treatment and hospitalisation duration. Responsiveness to the needs of people affected by MDR/RR-TB and health system constraints was achieved through implementation of flexible models, or the implementation of multiple models in a district.. Understanding how models for organising care have evolved may assist policy implementers to tailor implementation to promote particular patterns of care organisation or encourage flexibility, based on patient needs and local health system resources. Our approach can contribute towards the development of a health systems typology for understanding how policy-driven models of service delivery are implemented in the context of variable resources.

Topics: Antitubercular Agents; Hospitalization; Humans; Rifampin; South Africa; Tuberculosis, Multidrug-Resistant

GeneXpert MTB/RIF (Xpert) assay was applied widely to detect Mycobacterium tuberculosis (MTB) and rifampicin resistance.. Retrospectively investigated the association among treatment histories, phenotypic drug susceptibility testing (pDST) results, and clinical outcomes of patients infected with probe A absent mutation isolate confirmed by Xpert.. 63 patients with only probe A absent mutation and 40 with additional pDST results were analyzed. 24 (60.0%) patients had molecular-phenotypic discordant rifampicin (RIF) susceptibility testing results, including 12 (12/13, 92.3%) new tuberculosis (TB) patients and 12 (12/27, 44.4%) retreated ones. 28 (28/39, 71.8%) retreated patients received first-line treatment regime within two years with failed outcomes. New patients had better treatment outcomes than retreated ones (successful: 83.3% VS. 53.8%; P value = 0.02). The clinical results of RIF-susceptible TB confirmed by pDST were not better than RIF-resistant TB (successful: 62.5% VS. 50.0%; P value = 0.43). INH-resistant TB and INH-susceptible TB had similar treatment outcomes too (successful: 61.5% VS. 50.0%; P value = 0.48). 11 (11/12, 91.7%) new patients treated with the short treatment regimen (STR) had successful outcomes.. More than half of mono probe A absent isolates had RIF molecular-phenotypic discordance results, especially in new patients. Probe A mutations were significantly associated with unsuccessful clinical outcomes, whether the pDST results were RIF susceptible or not. STR was the best choice for new patients.. retrospectively registered in Wuhan Jinyintan Hospital (No. 2021-KY-16).

Topics: Humans; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis; Tuberculosis, Multidrug-Resistant

Multidrug-resistant tuberculosis (MDR-TB) requires treatment with fluoroquinolone (FLQ) drugs, however, the excessive use of FLQ has led to the rise of extensively drug-resistant TB. In 2019, ~ 20% of total MDR-TB cases were estimated to be resistant to FLQ drugs. In the present study, we developed and evaluated the utility of high-resolution melt curve analysis (HRM) for the rapid detection of FLQ-resistant Mycobacterium tuberculosis for the first time directly from sputum samples. A reference plasmid library was generated for the most frequently observed mutations of gyrA gene and was used to discriminate between mutant and wild-type samples in the FLQ-HRM assay. The developed assay was evaluated on n = 25 MDR M. tuberculosis clinical isolates followed by validation on archived sputum DNA (n = 88) using DNA sequencing as a gold standard. The FLQ-HRM assay showed a 100% sensitivity [95% Confidence Interval (CI): 71.5 to 100] and specificity (95% CI: 39.7 to 100) in smear-positive category, and a sensitivity of 88.9% (95% CI: 77.3 to 95.8) with 84.2% (95% CI: 60.4 to 96.6) specificity in smear-negative category. The assay showed a high level of concordance of ~ 90% (κ = 0.74) with DNA sequencing, however, we were limited by the absence of phenotypic drug susceptibility testing data. In conclusion, HRM is a rapid, cost-effective (INR 150/USD 1.83) and closed-tube method for direct detection of FLQ resistance in sputum samples including direct smear-negative samples.

Topics: Antitubercular Agents; Fluoroquinolones; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant

As an anti-tuberculosis target, DprE1 contains two flexible loops (Loop I and Loop II) which have never been exploited for developing DprE1 inhibitors. Here Leu317 in Loop II was discovered as a new functional site to combat drug-resistance in Mycobacterium strains. Based on TCA1, LZDT1 was designed to optimize the hydrophobic interaction with Leu317. A subsequent biochemical and cellular assay displayed increased potency of LZDT1 in inhibiting DprE1 and killing drug-sensitive/-resistant Mycobacterium strains. The improved activity of LZDT1 and its analogue LZDT2 against multidrug resistant tuberculosis was particularly highlighted. For LZDT1, its enhanced interaction with Leu317 also impaired the drug-insensitivity of DprE1 caused by Cys387 mutation. A new nonbenzothiazole lead (LZDT10) with reduced Cys387-dependence was further produced by optimizing interactions with Leu317, improvement directions for LZDT10 were discussed as well. Our research underscores the value of potential functional sites in disordered loops, and affords a feasible way to develop these functional sites into opportunities for drug-resistance management.

Topics: Alcohol Oxidoreductases; Antitubercular Agents; Bacterial Proteins; Dose-Response Relationship, Drug; Humans; Microbial Sensitivity Tests; Molecular Structure; Mycobacterium tuberculosis; Structure-Activity Relationship; Tuberculosis, Multidrug-Resistant

A series of thiophene-benzenesulfonamide derivatives was designed and synthesized by exploring the structure-activity relationship of lead compounds 2,3-disubstituted thiophenes 25a and 297F as antituberculosis agents, which displayed potent antimycobacterial activity against drug-susceptible and clinically isolated drug-resistant tuberculosis. In particular, compound 17b, which had improved activity (minimum inhibitory concentration of 0.023 μg/mL) compared with the lead compounds, displayed good intracellular antimycobacterial activity in macrophages with a reduction of 1.29 log

Topics: Animals; Antitubercular Agents; Benzenesulfonamides; Mice; Microbial Sensitivity Tests; Molecular Docking Simulation; Mycobacterium tuberculosis; Structure-Activity Relationship; Sulfonamides; Thiophenes; Tuberculosis, Multidrug-Resistant

Ever increasing drug resistance has become an impeding threat that continues to hamper effective tackling of otherwise treatable tuberculosis (TB). Such dismal situation necessitates identification and exploration of multitarget acting newer chemotypes with bactericidal efficacy as a priority, that could efficiently hinder uncontrolled spread of TB. In this context, herein we present design, synthesis and bio-evaluation of chalcone tethered bezoxazole-2-amines as promising anti-TB chemotypes. Preliminary screening of 24 compounds revealed initial hits 3,4,5-trimethoxyphenyl and 5-nitrofuran-2-yl derivative exhibiting selective inhibition of Mycobacterium tuberculosis (Mtb) H37Rv. Further, structural optimization of hit compounds generated 12 analogues, amongst which 5-nitrofuran-2-yl derivatives displayed potent inhibition of not only drug-susceptible (DS) Mtb but also clinical isolates of drug-resistant (DR) Mtb strains equipotently. Moreover, cell viability test against Vero cells found these compounds with favourable selectivity. Time kill analysis led to the identification of the lead compound (E)-1-(4-((5-chlorobenzo[d]oxazol-2-yl)amino)phenyl)-3-(5-nitrofuran-2-yl)prop-2-en-1-one, that demonstrated bactericidal killing of Mtb bacilli. Together with acceptable microsomal stability, the lead compound of the series manifested all desirable traits of a promising antitubercular agent.

Topics: Amines; Animals; Antitubercular Agents; Benzoxazoles; Chlorocebus aethiops; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Nitrofurans; Tuberculosis; Tuberculosis, Multidrug-Resistant; Vero Cells

Multidrug resistant tuberculosis (MDR-TB) remains a major human health challenge. Bedaquiline was approved in 2012 by the US FDA, and listed by WHO as a treatment for multidrug-resistant tuberculosis (MDR-TB) in 2018. However, the side effects of bedaquiline including the risk of unexplained mortality, QTc prolongation and hepatotoxicity limit its wide clinical use. Based on bedaquiline, we describe herein discovery and development of a novel diarylpyridine series, which led to identification of WX-081 (sudapyridine, 21l). It displayed excellent anti-mycobacterial activity against M. tuberculosis H37Rv in vitro and in vivo and low cytotoxicity; additionally WX-081 had excellent pharmacokinetic parameters in animals, better lung exposure and lower QTc prolongation potential compared to bedaquiline. WX-081 is currently under clinical phase II development (NCT04608955).

Topics: Animals; Antitubercular Agents; Long QT Syndrome; Mycobacterium tuberculosis; Tuberculosis, Multidrug-Resistant

Multidrug-resistant pulmonary tuberculosis (MDR-TB) is a major health problem worldwide. The treatment for MDR-TB requires medications for a long duration (up to 20-24 months) with second-line drugs resulting in unfavorable outcomes. Nitroimidazoles are promising antimycobacterial agents known to inhibit both aerobic and anaerobic mycobacterial activity. Delamanid and pretomanid are two nitroimidazoles approved by the regulatory agencies for MDR-TB treatment. However, both agents possess unsatisfactory absorption and QTc prolongation. In our search for a safer nitroimidazole, we discovered JBD0131 (2). It exhibited excellent anti-mycobacterial activity against M. tuberculosis H37Rv in vitro and in vivo, improved PK and absorption, reduced QT prolongation potential of delamanid. JBD0131 is currently in clinical development in China for pulmonary tuberculosis (CTR20202308).

Topics: Antitubercular Agents; Humans; Mycobacterium tuberculosis; Nitroimidazoles; Oxazoles; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Topics: Antitubercular Agents; Diarylquinolines; Fluoroquinolones; Humans; Rifampin; Tuberculosis, Multidrug-Resistant

Topics: Antibiotics, Antitubercular; Humans; Rifampin; Tuberculosis, Multidrug-Resistant

The WHO End TB Strategy requires drug susceptibility testing and treatment of all people with tuberculosis, but second-line diagnostic testing with line-probe assays needs to be done in experienced laboratories with advanced infrastructure. Fewer than half of people with drug-resistant tuberculosis receive appropriate treatment. We assessed the diagnostic accuracy of the rapid Xpert MTB/XDR automated molecular assay (Cepheid, Sunnyvale, CA, USA) to overcome these limitations.. We did a prospective study involving individuals presenting with pulmonary tuberculosis symptoms and at least one risk factor for drug resistance in four sites in India (New Delhi and Mumbai), Moldova, and South Africa between July 31, 2019, and March 21, 2020. The Xpert MTB/XDR assay was used as a reflex test to detect resistance to isoniazid, fluoroquinolones, ethionamide, amikacin, kanamycin, and capreomycin in adults with positive results for Mycobacterium tuberculosis complex on Xpert MTB/RIF or Ultra (Cepheid). Diagnostic performance was assessed against a composite reference standard of phenotypic drug-susceptibility testing and whole-genome sequencing. This study is registered with ClinicalTrials.gov, number NCT03728725.. Of 710 participants, 611 (86%) had results from both Xpert MTB/XDR and the reference standard for any drug and were included in analysis. Sensitivity for Xpert MTB/XDR detection of resistance was 94% (460 of 488, 95% CI 92-96) for isoniazid, 94% (222 of 235, 90-96%) for fluoroquinolones, 54% (178 of 328, 50-61) for ethionamide, 73% (60 of 82, 62-81) for amikacin, 86% (181 of 210, 81-91) for kanamycin, and 61% (53 of 87, 49-70) for capreomycin. Specificity was 98-100% for all drugs. Performance was equivalent to that of line-probe assays. The non-determinate rate of Xpert MTB/XDR (ie, invalid M tuberculosis complex detection) was 2·96%.. The Xpert MTB/XDR assay showed high diagnostic accuracy and met WHO's minimum target product profile criteria for a next-generation drug susceptibility test. The assay has the potential to diagnose drug-resistant tuberculosis rapidly and accurately and enable optimum treatment.. German Federal Ministry of Education and Research through KfW, Dutch Ministry of Foreign Affairs, and Australian Department of Foreign Affairs and Trade.

Topics: Adult; Amikacin; Australia; Capreomycin; Cross-Sectional Studies; Drug Resistance, Bacterial; Ethionamide; Fluoroquinolones; Humans; Isoniazid; Kanamycin; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Prospective Studies; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis; Tuberculosis, Multidrug-Resistant

In all cases, the WGS-based procedure was able to identify correctly the MTB species. Compared to MGIT drug susceptibility testing (DST), the sensitivity and specificity of genetic prediction of resistance to first-line antibiotics were respectively 100 and 99% (rifampicin, RIF), 90.5 and 100% (isoniazid, INH), 100 and 98% (ethambutol, EMB) and 61.1 and 100% (pyrazinamide, PZA). The negative predictive value was above 95% for these four first-line drugs. A positive predictive value of 100% was calculated for INH and PZA, 80% for RIF and 45% for EMB.. Our study confirms the effectiveness of WGS for the rapid detection of

Topics: Antitubercular Agents; Belgium; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Sensitivity and Specificity; Tuberculosis; Tuberculosis, Multidrug-Resistant; Whole Genome Sequencing

Bedaquiline improves outcomes of patients with rifampicin-resistant and multidrug-resistant (MDR) tuberculosis; however, emerging resistance threatens this success. We did a cross-sectional and longitudinal analysis evaluating the epidemiology, genetic basis, and treatment outcomes associated with bedaquiline resistance, using data from South Africa (2015-19).. Patients with drug-resistant tuberculosis starting bedaquiline-based treatment had surveillance samples submitted at baseline, month 2, and month 6, along with demographic information. Culture-positive baseline and post-baseline isolates had phenotypic resistance determined. Eligible patients were aged 12 years or older with a positive culture sample at baseline or, if the sample was invalid or negative, a sample within 30 days of the baseline sample submitted for bedaquiline drug susceptibility testing. For the longitudinal study, the first surveillance sample had to be phenotypically susceptible to bedaquiline for inclusion. Whole-genome sequencing was done on bedaquiline-resistant isolates and a subset of bedaquiline-susceptible isolates. The National Institute for Communicable Diseases tuberculosis reference laboratory, and national tuberculosis surveillance databases were matched to the Electronic Drug-Resistant Tuberculosis Register. We assessed baseline resistance prevalence, mutations, transmission, cumulative resistance incidence, and odds ratios (ORs) associating risk factors for resistance with patient outcomes.. Between Jan 1, 2015, and July 31, 2019, 8041 patients had surveillance samples submitted, of whom 2023 were included in the cross-sectional analysis and 695 in the longitudinal analysis. Baseline bedaquiline resistance prevalence was 3·8% (76 of 2023 patients; 95% CI 2·9-4·6), and it was associated with previous exposure to bedaquiline or clofazimine (OR 7·1, 95% CI 2·3-21·9) and with rifampicin-resistant or MDR tuberculosis with additional resistance to either fluoroquinolones or injectable drugs (pre-extensively-drug resistant [XDR] tuberculosis: 4·2, 1·7-10·5) or to both (XDR tuberculosis: 4·8, 2·0-11·7). Rv0678 mutations were the sole genetic basis of phenotypic resistance. Baseline resistance could be attributed to previous bedaquiline or clofazimine exposure in four (5·3%) of 76 patients and to primary transmission in six (7·9%). Odds of successful treatment outcomes were lower in patients with baseline bedaquiline resistance (0·5, 0·3-1). Resistance during treatment developed in 16 (2·3%) of 695 patients, at a median of 90 days (IQR 62-195), with 12 of these 16 having pre-XDR or XDR.. Bedaquiline resistance was associated with poorer treatment outcomes. Rapid assessment of bedaquiline resistance, especially when patients were previously exposed to bedaquiline or clofazimine, should be prioritised at baseline or if patients remain culture-positive after 2 months of treatment. Preventing resistance by use of novel combination therapies, current treatment optimisation, and patient support is essential.. National Institute for Communicable Diseases of South Africa.

Topics: Antitubercular Agents; Clofazimine; Cross-Sectional Studies; Diarylquinolines; Humans; Longitudinal Studies; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

There is limited research assessing the utility of the Xpert Mycobacterium tuberculosis/rifampin (MTB/RIF) assay for the analysis of bronchoalveolar lavage fluid (BALF) in Chinese patients with suspected pulmonary tuberculosis (PTB). Thus, our objective was to determine the diagnostic accuracy of the Xpert MTB/RIF assay and evaluate its utility for the determination of rifampicin resistance.. We retrospectively analyzed BALF from 214 patients with suspected PTB between January 2018 and March 2019. Using mycobacterial culture or final clinical diagnosis as the reference standard, the diagnostic accuracy of the smear microscopy (SM), tuberculosis bacillus DNA (TB-DNA), Xpert MTB/RIF assay, and the determination of rifampicin resistance based on the Xpert MTB/RIF assay were compared.. As compared to mycobacterial culture, the sensitivity of the Xpert MTB/RIF assay, SM, and TB-DNA were 85.5% (74.2%-93.1%), 38.7% (26.6%-51.9%), and 67.7% (54.7%-79.1%), respectively. As compared to the final diagnosis, the specificity of the Xpert MTB/RIF assay, SM, and TB-DNA were 100.0% (95.9%-100.0%), 94.3% (87.1%-98.1%), and 98.9% (93.8%-100.0%), respectively. The sensitivity and specificity of the rifampicin resistance detection using the Xpert MTB/RIF assay were 100% and 98.0%, respectively, with liquid culture as the reference.. This study demonstrates that the analysis of BALF with the Xpert MTB/RIF assay provides a rapid and accurate tool for the early diagnosis of PTB. The accuracy of diagnosis was superior compared with the SM and TB-DNA. Moreover, Xpert is a quick and accurate method for the diagnosis of rifampicin-resistant tuberculosis and can also provide more effective guidance for the treatment of PTB or multidrug-resistant tuberculosis (MDR-TB).

Topics: Adult; Antibiotics, Antitubercular; Bronchoalveolar Lavage Fluid; Drug Resistance, Multiple, Bacterial; Female; Humans; Male; Middle Aged; Molecular Typing; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Multidrug-resistant tuberculosis (isoniazid/rifampin[RIF]-resistant TB) ravages developing countries. Fitness is critical in clinical outcomes. Previous studies on RIF-resistant TB (RR-TB) showed competitive fitness gains and losses, with rpoB-S450L as the most isolated/fit mutation. This study measured virulence/resistance genes, phthiocerol dimycocerosate (PDIM) levels and their relationship with rpoB S450L ATCC25618 RR-TB strain fitness. After obtaining 10 different RR-TB GenoType MTBDRplus 2.0-genotyped isolates (with nontyped, S441, H445 and S450 positions), only one S450L isolate (R9, rpoB-S450L ATCC 25618, RR 1 μg/mL) was observed, with H445Y being the most common. A competitive fitness in vitro assay with wild-type (wt) ATCC 25618: R9 1:1 in 50 mL Middlebrook 7H9/OADC was performed, and generation time (G) in vitro and relative fitness were obtained. mRNA and PDIM were extracted on log and stationary phases. Fitness decreased in rpoB S450L and H445Y strains, with heterogeneous fitness cues in three biological replicas of rpoB-S450L: one high and two low fitness replicas. S450L strain had significant pknG increase. Compared with S450L, wt-rpoB showed increased polyketide synthase ppsA expression and high PDIM peak measured by HPLC-MS in log phase compared to S450L. This contrasts with previously increased PDIM in other RR-TB isolates.

Topics: Antitubercular Agents; Bacterial Proteins; Humans; Lipids; Mycobacterium tuberculosis; Protein Serine-Threonine Kinases; Rifampin; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Emigrants and Immigrants; Extensively Drug-Resistant Tuberculosis; Humans; Isoniazid; Mycobacterium tuberculosis; Refugees; Rifampin; Tuberculosis, Multidrug-Resistant; United States

This study was planned to estimate the proportion of confirmed multi-drug resistance pulmonary tuberculosis (TB) cases out of the presumptive cases referred to DTC (District Tuberculosis Center) Jodhpur for diagnosis; to identify clinical and socio-demographic risk factors associated with the multidrug-resistant pulmonary TB and to assess the spatial distribution to find out clustering and pattern in the distribution of pulmonary TB with the help of Geographic Information System (GIS). In the Jodhpur district, 150 confirmed pulmonary multi-drug resistant tuberculosis (MDR-TB) cases, diagnosed by probe-based molecular drug susceptibility testing method and categorized as MDR in DTC's register (District Tuberculosis Center), were taken. Simultaneously, 300 control of confirmed non-MDR or drug-sensitive pulmonary TB patients were taken. Statistical analysis was done with logistic regression. In addition, for spatial analysis, secondary data from 2013-17 was analyzed using Global Moran's I and Getis and Ordi (Gi*) statistics. In 2012-18, a total of 12563 CBNAAT (Cartridge-based nucleic acid amplification test) were performed. 2898 (23%) showed M. TB positive but rifampicin sensitive, and 590 (4.7%) showed rifampicin resistant. Independent risk factors for MDR TB were ≤60 years age (AOR 3.0, CI 1.3-7.1); male gender (AOR 3.4, CI 1.8-6.7); overcrowding (AOR 1.6, CI 1.0-2.7); using chulha (smoke appliance) for cooking (AOR 2.5, CI 1.2-4.9), past TB treatment (AOR 5.7, CI 2.9-11.3) and past contact with MDR patient (AOR 10.7, CI 3.7-31.2). All four urban TUs (Tuberculosis Units) had the highest proportion of drug-resistant pulmonary TB. There was no statistically significant clustering, and the pattern of cases was primarily random. Most of the hotspots generated were present near the administrative boundaries of TUs, and the new ones mostly appeared in the area near the previous hotspots. A random pattern seen in cluster analysis supports the universal drug testing policy of India. Hotspot analysis helps cross administrative border initiatives with targeted active case finding and proper follow-up.

Topics: Humans; India; Male; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Risk Factors; Smoke; Spatial Analysis; Tuberculosis; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Antimicrobial resistance develops following the accrual of mutations in the bacterial genome, and may variably impact organism fitness and hence, transmission risk. Classical representation of tuberculosis (TB) dynamics using a single or two strain (DS/MDR-TB) model typically does not capture elements of this important aspect of TB epidemiology. To understand and estimate the likelihood of resistance spreading in high drug-resistant TB incidence settings, we used epidemiological data to develop a mathematical model of Mycobacterium tuberculosis (Mtb) transmission.. A four-strain (drug-susceptible (DS), isoniazid mono-resistant (INH-R), rifampicin mono-resistant (RIF-R) and multidrug-resistant (MDR)) compartmental deterministic Mtb transmission model was developed to explore the progression from DS- to MDR-TB in The Philippines and Viet Nam. The models were calibrated using data from national tuberculosis prevalence (NTP) surveys and drug resistance surveys (DRS). An adaptive Metropolis algorithm was used to estimate the risks of drug resistance amplification among unsuccessfully treated individuals.. The estimated proportion of INH-R amplification among failing treatments was 0.84 (95% CI 0.79-0.89) for The Philippines and 0.77 (95% CI 0.71-0.84) for Viet Nam. The proportion of RIF-R amplification among failing treatments was 0.05 (95% CI 0.04-0.07) for The Philippines and 0.011 (95% CI 0.010-0.012) for Viet Nam.. The risk of resistance amplification due to treatment failure for INH was dramatically higher than RIF. We observed RIF-R strains were more likely to be transmitted than acquired through amplification, while both mechanisms of acquisition were important contributors in the case of INH-R. These findings highlight the complexity of drug resistance dynamics in high-incidence settings, and emphasize the importance of prioritizing testing algorithms which allow for early detection of INH-R.

Topics: Antitubercular Agents; Drug Resistance; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Multi drug or rifampicin resistant tuberculosis (MDR/RR-TB) is a major burden to TB prevention and eradication globally. Since 2016, WHO guidelines have included options for treating MDR/RR-TB with a standard regimen of 9 to 11 months duration (the 'shorter regimen') rather than an individual regimen of at least 20 months. This regimen has been introduced in Indonesia since September 2017. Therefore, we aimed to determine the success rate and factors associated with the treatment outcome of shorter injectable based regimen in West Java province, Indonesia.. This was a retrospective cohort study of MDR/RR-TB patients aged over 18 years old who received the shorter injectable based regimen between September 2017 and December 2020. We defined successful outcomes as the combined proportion of patients who were cured or had complete treatment. While, unsuccessful outcomes were defined as the combined proportion of patients who died from any causes, failure, and loss to follow-up (LTFU).. A total of 315 patients were included in this study. The success rate was 64.5%. Multivariate analysis showed male gender (aRR = 1.18, 95% CI 1.04 to 1.34) increased the chance of successful outcome, while malnutrition (aRR = 0.78, 95% CI 0.68 to 0.89), history of previous TB treatment (aRR = 0.80%CI 0.68 to 0.94), and time of culture conversion >2 months (aRR = 0.72 (95% CI 0.59 to 0.87) decreased the chance of successful outcome.. History of previous TB treatment, time of culture conversion >2 months, and malnutrition were independent factors that decrease the chance for success rate, while male gender increase the likelihood for success rate of patients treated by the shorter injectable based regimen.

Topics: Female; Humans; Indonesia; Injections; Male; Middle Aged; Multivariate Analysis; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant

The aim: To study the structure of adverse drug reactions and the effectiveness of treatment among patients with drug-resistant tuberculosis who follow the modified short-term and individualized treatment regimens.. Materials and methods: The analysis of 138 inpatient medical records, outpatient health cards and electronic database of the patient register was conducted. Resistant strains of MTB were microbiologically verified in all the patients. All the patients underwent clinical-laboratory, instrumental microbiological, genetic-molecular (GeneXpert MTB / RIF) methods of examination, both for diagnosis and monitoring of the effectiveness of treatment. In order to prevent complications and control adverse reactions, all the patients were briefly screened for peripheral neuropathy, basic audiometry, the QTc interval was determined, visual acuity and color perception were checked.. Results: At individualized treatment regimen of tuberculosis, adverse reactions were 3.5 times more common than in patients with modified short-term therapy, in 65 (68.4%) cases and in 8 (18.6%) cases, respectively. Accordingly, the effectiveness of treatment differed in both groups. Prevailing in long-term treatment were: treatment interruption treatment gap, treatment failure, continued treatment. In patients receiving short-term regimens, the cured rate was almost twice as common as in the second group.. Conclusions: Timely detection cases of resistant tuberculosis and using linear probe analysis (LPA) - GenoType MTBDRplus for diagnosis of fluoroquinolone resistance, will allow the use of modified short-term treatment regimens for tuberculosis. Which in turn will reduce the number of side effects and improve the outcome of treatment.

Topics: Humans; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis; Tuberculosis, Multidrug-Resistant

Strengthening second-line drug-resistant tuberculosis (TB) detection is a priority. GenoType MTBDRplus VER 2.0 performance is reduced with non-recommended ramp rate usage (temperature change speed between PCR cycles); however, ramp rate's effect on GenoType MTBDRsl VER 2.0 (MTBDRsl) performance, is unknown. Fifty-two Xpert MTB/RIF Ultra-positive rifampicin-resistant smear-negative sputa and a Mycobacterium tuberculosis dilution series were tested at a manufacturer-recommended (2.2°C/second) or suboptimal (4.0°C/second) ramp rate. M. tuberculosis-complex-DNA positivity, indeterminates, fluoroquinolone- and second-line injectable-resistance accuracy, banding differences, and, separately, inter-reader variability were assessed. Five (39%) of 13 re-surveyed laboratories did not use the manufacturer-recommended ramp rate. On sputum, 2.2°C/second improved indeterminates versus 4.0°C/second (0 of 52 versus 7 of 51; P = 0.006), incorrect drug-class diagnostic calls (0 of 104 versus 6 of 102; P = 0.013), and incorrect banding calls (0 of 1300 versus 54 of 1275; P < 0.001). Similarly, 2.2°C/second improved valid results [(52 of 52 versus 41 of 51; +21% (P = 0.001)] and banding call inter-reader variability [34 of 1300 (3%) versus 52 of 1300 (4%); P = 0.030]. At the suboptimal ramp rate, false-resistance and false-susceptible calls resulted from wild-type band absence rather than mutant band appearance, resulting in misclassification of moxifloxacin resistance level from high-to-low. Suboptimal ramp rate contributes to poor MTBDRsl performance. Laboratories must ensure that the manufacturer-recommended ramp rate is used.

Topics: Antitubercular Agents; Genotype; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant

Treatment of multidrug-resistant or rifampicin-resistant tuberculosis (MDR/RR-TB), although improved in recent years with shorter, more tolerable regimens, remains largely standardized and based on limited drug susceptibility testing (DST). More individualized treatment with expanded DST access is likely to improve patient outcomes. To assess the potential of TB drug resistance prediction based on whole-genome sequencing (WGS) to provide more effective treatment regimens, we applied current South African treatment recommendations to a retrospective cohort of MDR/RR-TB patients from Khayelitsha, Cape Town. Routine DST and clinical data were used to retrospectively categorize patients into a recommended regimen, either a standardized short regimen or a longer individualized regimen. Potential regimen changes were then described with the addition of WGS-derived DST. WGS data were available for 1274 MDR/RR-TB patient treatment episodes across 2008 to 2017. Among 834 patients initially eligible for the shorter regimen, 385 (46%) may have benefited from reduced drug dosage or removing ineffective drugs when WGS data were considered. A further 187 (22%) patients may have benefited from more effective adjusted regimens. Among 440 patients initially eligible for a longer individualized regimen, 153 (35%) could have been switched to the short regimen. Overall, 305 (24%) patients had MDR/RR-TB with second-line TB drug resistance, where the availability of WGS-derived DST would have allowed more effective treatment individualization. These data suggest considerable benefits could accrue from routine access to WGS-derived resistance prediction. Advances in culture-free sequencing and expansion of the reference resistance mutation catalogue will increase the utility of WGS resistance prediction.

Topics: Antitubercular Agents; Cohort Studies; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; South Africa; Tuberculosis, Multidrug-Resistant

With increasing use of Xpert MTB/RIF a point of care molecular test for simultaneous detection of TB and resistance to rifampicin, a growing number of rifampicin resistant cases are being detected and notified. Insights into the variation and frequencies in the probe mutations obtained through Xpert testing in the RRTB case will form the baseline information for further investigation on drug resistance. In this study we did a retrospective analysis of the GeneXpert data obtained from patient samples received at a National reference laboratory in Chennai between the years 2014 and 2020 to look at the probe distribution, the variation in the mutation and explore its significance. Probe E mutation was most commonly identified followed by Probe D, Probe A, Probe B and Probe C. Coexistence of multiple probe mutations in low bacillary load samples could be related to prolonged amplification cycle leading to delayed hybridization of probes. In such instances reporting false RR in xpert testing is possible. The probe mutations of RR should be monitored in depth with inclusion of codon specific targets for management of drug sensitive TB. In addition, heteroresistance needs to be further tested by alternative genotypic methods to avoid false resistance.

Topics: Antibiotics, Antitubercular; Drug Resistance, Bacterial; Humans; India; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Concomitant use of bedaquiline (Bdq) and delamanid (Dlm) for multi-drug/rifampicin resistant tuberculosis (MDR/RR-TB) has raised concerns about a potentially poor risk-benefit ratio. Yet this combination is an important alternative for patients infected with strains of TB with complex drug resistance profiles or who cannot tolerate other therapies. We assessed safety and treatment outcomes of MDR/RR-TB patients receiving concomitant Bdq and Dlm, along with other second-line anti-TB drugs.. We conducted a multi-centric, prospective observational cohort study across 14 countries among patients receiving concomitant Bdq-Dlm treatment. Patients were recruited between April 2015 and September 2018 and were followed until the end of treatment. All serious adverse events and adverse events of special interest (AESI), leading to a treatment change, or judged significant by a clinician, were systematically monitored and documented.. Overall, 472 patients received Bdq and Dlm concomitantly. A large majority also received linezolid (89.6%) and clofazimine (84.5%). Nearly all (90.3%) had extensive disease; most (74.2%) had resistance to fluoroquinolones. The most common AESI were peripheral neuropathy (134, 28.4%) and electrolyte depletion (94, 19.9%). Acute kidney injury and myelosuppression were seen in 40 (8.5%) and 24 (5.1%) of patients, respectively. QT prolongation occurred in 7 patients (1.5%). Overall, 78.0% (358/458) had successful treatment outcomes, 8.9% died, and 7.2% experienced treatment failure.. Concomitant use of Bdq and Dlm, along with linezolid and clofazimine, is safe and effective for MDR/RR-TB patients with extensive disease. Using these drugs concomitantly is a good therapeutic option for patients with resistance to many anti-TB drugs.

Topics: Antitubercular Agents; Clofazimine; Cohort Studies; Diarylquinolines; Electrolytes; Fluoroquinolones; Humans; Linezolid; Nitroimidazoles; Oxazoles; Prospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant

Multidrug-resistant tuberculosis (MDR-TB) is increasing worldwide and is a major cause of death in many countries. It has become a major challenge for national tuberculosis control programs. Therefore, rapid identification of MDR strains of Mycobacterium tuberculosis and monitoring of their transmission could contribute significantly to the fight against tuberculosis. The GenoType MTBDRplus assay has been recommended by the World Health Organization to identify rifampicin (RIF)- and isoniazid (INH)-resistant M. Tuberculosis isolates. The objectives of this study were to evaluate the performance of the GenoType MTBDRplus test in the detection of rifampicin and isoniazid resistance of M. tuberculosis isolates in a Moroccan hospital and then to determine the frequency of mutations associated with resistance to these two major anti-tuberculosis drugs.. This is a retrospective study conducted at the bacteriology department of the Mohammed V military hospital over a period of one year from 01/01/2018 to 12/31/2019. A total of 92 isolates of M. tuberculosis from pulmonary and extra-pulmonary specimens were evaluated for drug susceptibility by MGIT™ 960 AST system and compared to the GenoType MTBDRplus assay. The MGIT™ 960 AST system was used as the gold standard for the evaluation of the GenoType MTBDRplus assay.. Sensitivity and specificity of the GenoType MTBDRplus assay for the detection of RIF-resistant M. tuberculosis isolates were 83.33% and 100%, respectively. Its sensitivity and specificity for the detection of INH-resistant M. tuberculosis were 88.23% and 100% respectively. The concordances of the GenoType MTBDRplus assay and the MGIT™ 960 AST system for the detection of sensitivity to RIF and INH were 99% (1/92) and 98% (2/92), respectively. Among the five RIF-resistant isolates, the MUT3 mutation in the rpoB gene (codon S531L mutation) was present in 80% of isolates, whereas mutations in the rpoB MUT1 gene were present in only one (20%) RIF-resistant isolate. INH resistance was detected in 15 isolates, of which nine isolates (60%) had specific mutations of the katG gene (codon S315T1) and conferred a high level of resistance to INH.. The results of this study have shown that the GenoType MTBDRplus test has a high sensitivity and specificity for the detection of resistance to RIF and INH.

Topics: Antitubercular Agents; Genotype; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

Tuberculosis burden among the incarcerated population is generally higher than that of general population. Early diagnosis and prompt initiation of treatment are key strategies to contain disease transmission. The aim of this study was to determine the time to treatment initiation among inmates with new smear or Xpert MTB/RIF positive pulmonary tuberculosis and explore risk factors associated with delayed treatment initiation in prison settings.. We conducted a retrospective cohort study using routine health care data from prison settings in Kzrgyz Republic on new pulmonary tuberculosis patients confirmed by smear microscopy or GeneXpert MTB/RIF during 2014-2019. We computed delay in start of treatment-days from specimen collection to treatment initiation-for exposure variables. We dichotomized treatment delay using 10-day cut-off point,and used logistic regression to identify factors associated with treatment delay.. Among 406 cases included into analysis, the median delay to treatment initiation was 7 days [IQR: 2-16 days]. Using 10-day cut-off, 189 (46.6%) patients had delayed treatment initiation. Treatment delay was negatively associated with smear positivity [adjusted OR (aOR) = 0.44, 95% CI 0.29-0.68] compared to smear negative patients, while patients with isoniazid resistant (aOR = 2.61, 95%CI 1.49-4.56) and rifampicin resistant tuberculosis (aOR = 4.14, 95%CI 2.56-6.77) had increased delay compared to patients who were sensitive for both rifampicin and isoniazid.. Timely diagnosis and effective treatment remain the cornerstone of TB control program populations in the general and in prison settings in particular. Prison authorities need to address all potential areas of delay in TB diagnosis and treatment to strengthen their TB control efforts so that prisons remain free of TB for detainees, prison staff and visitors. These include improved supply of TB drugs, early detection of TB cases and improved collaboration with the health authorities outside the prison system.

Topics: Humans; Isoniazid; Kyrgyzstan; Mycobacterium tuberculosis; Prisons; Retrospective Studies; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Topics: Antitubercular Agents; Hepatitis C; Humans; Rifampin; Tuberculosis, Multidrug-Resistant

Our objective was to evaluate the performance of whole-genome sequencing (WGS) from early positive liquid cultures for predicting Mycobacterium tuberculosis complex (MTBC) drug resistance. Clinical isolates were obtained from tuberculosis patients at Shanghai Pulmonary Hospital (SPH). Antimicrobial susceptibility testing (AST) was performed, and WGS from early Bactec mycobacterial growth indicator tube (MGIT) 960-positive liquid cultures was performed to predict the drug resistance using the TB-Profiler informatics platform. A total of 182 clinical isolates were enrolled in this study. Using phenotypic AST as the gold standard, the overall sensitivity and specificity for WGS were, respectively, 97.1% (89.8 to 99.6%) and 90.4% (83.4 to 95.1%) for rifampin, 91.0% (82.4 to 96.3%) and 95.2% (89.1 to 98.4%) for isoniazid, 100.0% (89.4 to 100.0%) and 87.3% (80.8 to 92.1%) for ethambutol, 96.6% (88.3 to 99.6%) and 61.8% (52.6 to 70.4%) for streptomycin, 86.8% (71.9 to 95.6%) and 95.8% (91.2 to 98.5%) for moxifloxacin, 86.5% (71.2 to 91.5%) and 95.2% (90.3 to 98.0%) for ofloxacin, 100.0% (54.1 to 100.0%) and 67.6% (60.2 to 74.5%) for amikacin, 100.0% (63.1 to 100.0%) and 67.2% (59.7 to 74.2%) for kanamycin, 62.5% (24.5 to 91.5%) and 88.5% (82.8 to 92.8%) for ethionamide, 33.3% (4.3 to 77.7%) and 98.3% (95.1 to 99.7%) for para-aminosalicylic acid, and 0.0% (0.0 to 12.3%) and 100.0% (97.6 to 100.0%) for cycloserine. The concordances of WGS-based AST and phenotypic AST were as follows: rifampin (92.9%), isoniazid (93.4%), ethambutol (89.6%), streptomycin (73.1%), moxifloxacin (94.0%), ofloxacin (93.4%), amikacin (68.7%), kanamycin (68.7%), ethionamide (87.4%), para-aminosalicylic acid (96.2%) and cycloserine (84.6%). We conclude that WGS could be a promising approach to predict MTBC resistance from early positive liquid cultures.

Topics: Amikacin; Aminosalicylic Acid; Antitubercular Agents; China; Cycloserine; Drug Resistance; Ethambutol; Ethionamide; Humans; Isoniazid; Kanamycin; Microbial Sensitivity Tests; Moxifloxacin; Mycobacterium tuberculosis; Ofloxacin; Rifampin; Streptomycin; Tuberculosis, Multidrug-Resistant

Heat shock proteins are essential in maintaining cellular protein function, especially during stress. Their influence in managing drug-induced stress in Tuberculosis is not clearly understood.. Study the expression of select genes of the DnaK/ClpB chaperone network to evaluate their role in stress response in Mycobacterium tuberculosis clinical isolates during exposure to Isoniazid (INH) and Rifampicin (RIF).. Sanger sequencing to detect drug-resistant mutations followed by Drug Susceptibility Testing and Minimum Inhibitory Concentration determination. Culturing the bacilli in vitro, exposed to 1/4, 1/2 and 1 × MIC, and RNA quantification of dnaK, dnaJ1, grpE and clpB genes by using Real-time PCR.. Susceptible isolates showed marginal down-regulation of two genes for INH, whereas all genes under-expressed against RIF. INH-resistant isolates had distinct expression profiles for inhA-15 and katG315 mutants. RIF-resistant bacilli did not have significant differential expression. MDR isolate showed up-regulation of all the four genes, with two genes over-expressing (≥4-fold).. We observed characteristic gene expression profiles for each isolate in response to lethal and sub-lethal doses of INH and RIF. This provides insight into the role of DnaK/ClpB chaperone network in managing drug-induced stress and facilitating resistance. Further, the knowledge could provide targets for new drugs and augmenters.

Topics: Antitubercular Agents; Bacterial Proteins; Catalase; Endopeptidase Clp; Heat-Shock Proteins; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Lymph Node; Tuberculosis, Multidrug-Resistant

We aimed to validate the performance of a newly developed real-time PCR assay using cobas® MTB-RIF/INH reagent on the cobas® 6800 system for detecting isoniazid (INH) and rifampicin (RIF) resistance, using Japanese Mycobacterium tuberculosis (MTB) isolates. In total, 119 mock sputum specimens spiked with resistant MTB were tested using the cobas® MTB-RIF/INH reagent. The whole genomes of all MTB isolates were sequenced by MiSeq and analysed for mutations/indels causing drug resistance. All isolates were tested for phenotypic drug susceptibility, then MTB negative sputa were collected and pooled to prepare mock sputum specimens for the study. The sensitivity and specificity for INH resistance at a concentration equal to 3 × the limit of detection were 77.8% and 90.0%, respectively; those for RIF resistance were 91.8% and 93.5%, respectively. The sensitivities for INH and RIF were statistically different (P = 0.014), but not the specificities (P = 0.624). Twenty-two false-susceptible and two false-resistant results were obtained in INH; meanwhile, six false-susceptible and three false-resistant results were obtained in RIF. False-resistance for INH and RIF was mainly due to disputed mutations. The cobas® MTB-RIF/INH reagent showed better performance than other rapid molecular tests.

Topics: Humans; Indicators and Reagents; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

Pharmacokinetic data for bedaquiline in children are limited. We described the pharmacokinetics and safety of bedaquiline in South African children and adolescents receiving treatment for multidrug/rifampicin-resistant tuberculosis (MDR/RR-TB) in routine care.. In this observational cohort study, children aged 6-17 years receiving bedaquiline at recommended doses as part of MDR/RR-TB treatment underwent semi-intensive pharmacokinetic sampling. Bedaquiline and the M2 metabolite plasma concentrations were quantified, and nonlinear mixed-effects modeling performed. Pediatric data were described using a pre-established model of bedaquiline pharmacokinetics in adults. The exposure reference was 187 µg ⋅ h/mL, the median weekly area under the curve (AUC) of adults at week 24 of treatment with bedaquiline. Safety was assessed through monthly clinical, blood and electrocardiogram monitoring, and treatment outcomes described.. Fifteen children (3 human immunodeficiency virus [HIV]-positive) with median age 13.3 years (range 6.5-16.3) were included. A bedaquiline pharmacokinetic model was adapted to be allometrically scaled in clearance and volume, centered in the median child population weight. Bedaquiline bioavailability was 57% of that in adults. Overall bedaquiline exposures were below target, and AUC reference attainment was achieved in only 3 (20%) children. Ten children experienced 27 adverse events at least possibly related to bedaquiline; no adverse events led to bedaquiline withdrawal. Two adverse events (arthritis and arthralgia) were considered severe, and 2 children had mild QT interval corrected for heart rate using Fridericia's formula (QT) prolongation.. The evaluated doses of bedaquiline in children ≥ 6 years of age were safe but achieved slightly lower plasma concentrations compared to adults receiving the recommended dose, possibly due to delayed food intake relative to bedaquiline administration.

Topics: Adolescent; Adult; Antitubercular Agents; Child; Diarylquinolines; HIV; HIV Infections; HIV Seropositivity; Humans; Rifampin; Tuberculosis, Multidrug-Resistant

The UK has implemented routine use of whole genome sequencing (WGS) in TB diagnostics. The WHO recommends addition of a fluoroquinolone for isoniazid mono-resistance, so early detection may be of use. The aim of this study was to describe the clinical utility and impact of WGS on treatment decisions for TB in a low incidence high resource clinical setting. The clinical turnaround time (TAT) for WGS was analysed in comparison to TB PCR using Xpert MTB/RIF (Cepheid, Sunnyvale, CA) results where available and subsequent phenotypic drug susceptibility testing (DST) when required.. This was a retrospective analysis of TB cases from January 2018 to March 2019 in London. Susceptibility and TAT by WGS, phenotypic DST, TB PCR using Xpert MTB/RIF were correlated to drug changes in order to describe the utility of WGS on treatment decisions on isoniazid mono-resistance in a low incidence high resource setting.. 189 TB cases were identified; median age 44 years (IQR 28-60), m:f ratio 112:77, 7 with HIV and 6 with previous TB. 80/189 cases had a positive culture and WGS result. 50/80 were fully sensitive to 1st line treatment on WGS, and the rest required additional DST. 20/80 cases required drug changes; 12 were defined by WGS: 8 cases had isoniazid mono-resistance, 2 had MDR-TB, 1 had isoniazid and pyrazinamide resistance and 1 had ethambutol resistance. The median TAT for positive culture was 16 days (IQR 12.5-20.5); for WGS was 35 days (IQR 29.5-38.75) and for subsequent DST was 86 days (IQR 69.5-96.75), resulting in non-WHO regimens for a median of 50.5 days (IQR 28.0-65.0). 9/12 has TB PCRs (Xpert MTB/RIF), with a median TAT of 1 day.. WGS clearly has a substantial role in our routine UK clinical settings with faster turnaround times in comparison to phenotypic DST. However, the majority of treatment changes defined by WGS were related to isoniazid resistance and given the 1 month TAT for WGS, it would be preferable to identify isoniazid resistance more quickly. Therefore if resources allow, diagnostic pathways should be optimised by parallel use of WGS and new molecular tests to rapidly identify isoniazid resistance in addition to rifampicin resistance and to minimise delays in starting WHO isoniazid resistance treatment.

Topics: Adult; Antitubercular Agents; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant; Whole Genome Sequencing

Drug-resistant tuberculosis (DR-TB) is a global health concern. QTc prolongation is a serious adverse effect in DR-TB patients receiving a shorter regimen. This study aimed to evaluate the correlation of moxifloxacin concentration, CRP, and inflammatory cytokines with QTc interval in DR-TB patients treated with a shorter regimen.. This study was performed in 2 groups of rifampicin-resistant (RR-TB) patients receiving shorter regimens. Correlation for all variables was analyzed.. CRP, IL-1β, and QTc baseline showed significant differences between 45 RR-TB patients on intensive phase and continuation phase with p-value of <0.001, 0.040, and <0.001, respectively. TNF-α and IL-6 between RR-TB patients on intensive phase and continuation phase showed no significant difference with p=0.530 and 0.477, respectively. CRP, TNF-α, IL-1 β, and IL-6 did not correlate with QTc interval in intensive phase (p=0.226, 0.281, 0.509, and 0.886, respectively), and also in continuation phase (0.805, 0.865, 0.406, 0.586, respectively). At 2 hours after taking the 48th-dose, moxifloxacin concentration did not correlate with QTc interval, both in intensive phase (p=0.576) and in continuation phase (p=0.691). At 1 hour before taking the 72nd-hour dose, moxifloxacin concentration also did not correlate with QTc interval in intensive phase (p=0.531) and continuation phase (p=0.209).. Moxifloxacin concentration, CRP, and inflammatory cytokines did not correlate with QTc interval in RR-TB patients treated with shorter regimens. The use of moxifloxacin is safe but should be routinely monitored and considered the presence of other risk factors for QTc prolongation in RR-TB patients who received shorter regimens.

Topics: Antitubercular Agents; C-Reactive Protein; Cytokines; Electrocardiography; Humans; Interleukin-6; Long QT Syndrome; Moxifloxacin; Rifampin; Tuberculosis, Multidrug-Resistant; Tumor Necrosis Factor-alpha

Second-line drug resistance (SLD) among tuberculosis (TB) patients is a serious emerging challenge towards global control of the disease. We characterized SLD-resistance conferring-mutations among TB patients with rifampicin and/or isoniazid (RIF and/or INH) drug-resistance tested at the Uganda National TB Reference Laboratory (NTRL) between June 2017 and December 2019.. This was a descriptive cross-sectional secondary data analysis of 20,508 M. tuberculosis isolates of new and previously treated patients' resistant to RIF and/or INH. DNA strips with valid results to characterise the SLD resistance using the commercial Line Probe Assay Genotype MTBDRsl Version 2.0 Assay (Hain Life Science, Nehren, Germany) were reviewed. Data were analysed with STATAv15 using cross-tabulation for frequency and proportions of known resistance-conferring mutations to injectable agents (IA) and fluoroquinolones (FQ).. Among the eligible participants, 12,993/20,508 (63.4%) were male and median (IQR) age 32 (24-43). A total of 576/20,508 (2.8%) of the M. tuberculosis isolates from participants had resistance to RIF and/or INH. These included; 102/576 (17.7%) single drug-resistant and 474/576 (82.3%) multidrug-resistant (MDR) strains. Only 102 patients had test results for FQ of whom 70/102 (68.6%) and 01/102 (0.98%) had resistance-conferring mutations in the gyrA locus and gyrB locus respectively. Among patients with FQ resistance, gyrAD94G 42.6% (30.0-55.9) and gyrA A90V 41.1% (28.6-54.3) mutations were most observed. Only one mutation, E540D was detected in the gyrB locus. A total of 26 patients had resistance-conferring mutations to IA in whom, 20/26 77.0% (56.4-91.0) had A1401G mutation in the rrs gene locus.. Our study reveals a high proportion of mutations known to confer high-level fluoroquinolone drug-resistance among patients with rifampicin and/or isoniazid drug resistance. Utilizing routinely generated laboratory data from existing molecular diagnostic methods may aid real-time surveillance of emerging tuberculosis drug-resistance in resource-limited settings.

Topics: Adult; Antitubercular Agents; Cross-Sectional Studies; Drug Resistance, Multiple, Bacterial; Female; Fluoroquinolones; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant; Uganda; Young Adult

Topics: Antitubercular Agents; Aspartate-Semialdehyde Dehydrogenase; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Phenotypic drug susceptibility testing is the most common approach to assess drug-resistant isolates; however, molecular methods of drug susceptibility testing are fast, accurate hence, offer less time for transmission during the diagnosis period. As data on the molecular methods regarding injectable drug resistance in the Punjab province of Pakistan is limited, therefore in this study, we aimed to analyze the mutations in the rrs gene behind second-line injectable drug resistance.. Mycobacterium tuberculosis isolates were collected from the sputum of 5362 TB suspects. The strains confirmed for resistant to injectable drugs through drug susceptibility testing were further proceeded. The 1537bp rrs gene was amplified with the help of three sets of primers with overlapping regions and DNA sequencing was performed. Obtained sequences were aligned with reference sequence to find mutations. RFLP-PCR method was also optimized for rapid detection of a common (143bp and 205bp) rrs gene mutation.. Among 172 rifampicin resistance isolates, 163(95%) were resistant to both rifampicin and isoniazid, and 9 (5%) were resistant to only rifampicin. Among the resistant samples, 12 (6.9%) samples were resistant to all three injectable drugs. Sixty out of 172 (34.9%) samples showed resistance to at least one drug and 10 (5.8%) samples were resistant to two drugs among the 3 s-line drugs. Sequencing analysis showed novel mutations in different samples at positions 443InsC, 19DelT, 29G>A, 48C>T, 50G>C, 265InsT, 423T>G, 476InsA, 446A>G, 563DelA, 695G>A, 805DelA, 900G>A, and 1510A>G, while some already reported mutations at position 1401A>G, 1402A>G, and 1484G>T were also observed. MIC of novel rrs gene mutations in KAN, CAP, and AMK resistant isolates were found between 2.5 mg/L-3.05 mg/L, 2.08 mg/L-3.0 mg/L, and 2.1 mg/L-2.7 mg/L respectively.. Novel mutations in the rrs gene reported in this study may confer second-line injectable drugs resistance in Mtb. This molecular insight into second-line injectable drug resistance is useful for better management of resistance Mtb in high burden countries.

Topics: Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Genes, Bacterial; Humans; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Pakistan; Rifampin; Tuberculosis, Lymph Node; Tuberculosis, Multidrug-Resistant

There are limited data on the. Drug susceptibility testing (DST) was performed by culturing MTB isolates on the Lowenstein-Jensen medium using the proportion method.. Out of 963 MTB isolates, 927 (96.3%) were recovered from Iranian cases and 36 (3.7%) were from Afghan immigrants. Based on DST, 59 (6.1%) showed any drug resistance pattern, while 18 patients (1.9%) were multidrug-resistant (MDR) or rifampicin-resistant (RR). Resistance to streptomycin (STR), isoniazid (INZ), rifampicin (RIN), and ethambutol (ETL) was reported in 33 (3.4%), 28 (2.9%), 18 (1.9%), and 12 isolates (1.2%), respectively.. The rate of MDR/RR in four northern provinces of Iran was in line with previous reports from the World Health Organization. Due to proximity to the former Soviet Union, which had a high rate of MDR/RR isolates, the establishment of cross-border tuberculosis (TB) control strategies is recommended to reduce the possibility of MDR-TB transmission. Moreover, DST for all TB cases is recommended as an effective diagnostic tool for optimal monitoring and control of drug resistance in these areas. Future studies with a molecular epidemiology approach will be needed to evaluate the transmission dynamics of MTB in these regions.

Topics: Antitubercular Agents; Drug Resistance; Humans; Iran; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

BACKGROUND This study aimed to investigate the factors associated with non-adherence of prescribed treatment in patients with multidrug-resistant and rifampicin-resistant tuberculosis (MDR/RR-TB) in Anhui Province, China. MATERIAL AND METHODS A cross-sectional survey was conducted in each designated hospital between March 2020 and May 2021. A structured questionnaire was designed to collect categorical characteristics and the historical data of the study participants. Non-adherence was determined from patient medical records and face-to-face interviews using the questionnaire at each designated hospital for MDR/RR-TB. RESULTS A total of 201 patients with confirmed sputum cultures positive for MDR/RR-TB were enrolled, 27.4% of whom were non-adherent to MDR/RR-TB treatment. In Anhui, MDR patients had a high incidence of adverse events, of which gastrointestinal reactions accounted for the majority. Absence of other chronic diseases (odds ratio (OR) 0.401; 95% confidence interval (CI) 0.203-0.791) and having no drug discontinuation (OR 0.040; 95% CI 0.018-0.091) were protective predictors of adherence. Patients with MDR/RR-TB with secondary education level and above and monthly family income of $309.4 USD or higher were more likely to follow the guidelines. Those who received anti-tuberculosis treatment and those who lived in suburban areas were less likely to adhere to the treatment. Binary-logistic regression indicated that the risk factor of non-adherence was drug discontinuation. CONCLUSIONS Low education level, place of residence, poor financial conditions, presence of other chronic diseases, discontinuation of medication, and frequency of anti-tuberculosis treatments were influential factors of adherence to MDR/RR-TB treatment.

Topics: Antitubercular Agents; China; Cross-Sectional Studies; Humans; Odds Ratio; Rifampin; Risk Factors; Tuberculosis, Multidrug-Resistant

Current knowledge on resistance-conferring determinants in Mycobacterium tuberculosis is biased toward globally dominant lineages 2 and 4. In contrast, lineages 1 and 3 are predominant in India. In this study, we performed whole-genome sequencing of 498 MDR M. tuberculosis isolates from India to determine the prevalence of drug resistance mutations and to understand the genomic diversity. A retrospective collection of 498 M. tuberculosis isolates submitted to the National Institute for Research in Tuberculosis for phenotypic susceptibility testing between 2014 to 2016 were sequenced. Genotypic resistance prediction was performed using known resistance-conferring determinants. Genotypic and phenotypic results for 12 antituberculosis drugs were compared, and sequence data were explored to characterize lineages and their association with drug resistance. Four lineages were identified although lineage 1 predominated (43%). The sensitivity of prediction for isoniazid and rifampicin was 92% and 98%, respectively. We observed lineage-specific variations in the proportion of isolates with resistance-conferring mutations, with drug resistance more common in lineages 2 and 3. Disputed mutations (codons 430, 435, 445, and 452) in the

Topics: Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Humans; India; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Phylogeny; Retrospective Studies; Rifampin; Tuberculosis, Lymph Node; Tuberculosis, Multidrug-Resistant

The emergence and spread of resistant tuberculosis (TB) pose a threat to public health, so it is necessary to diagnose the drug-resistant forms in a clinically short time frame and closely monitor their transmission. In this study, we carried out a first whole genome sequencing (WGS)-based analysis of multidrug resistant (MDR) M. tuberculosis strains to explore the phylogenetic lineages diversity, drug resistance mechanisms, and ongoing transmission chains within the country. In total, 65 isolates phenotypically resistant to at least rifampicin and isoniazid collected in the Czech Republic in 2005-2020 were enrolled for further analysis. The agreement of the results obtained by WGS with phenotypic drug susceptibility testing (pDST) in the determination of resistance to isoniazid, rifampicin, pyrazinamide, streptomycin, second-line injectables and fluoroquinolones was more than 80%. Phylogenetic analysis of WGS data revealed that the majority of MDR M. tuberculosis isolates were the Beijing lineage 2.2.1 (n = 46/65; 70.8%), while the remaining strains belonged to Euro-American lineage. Cluster analysis with a predefined cut-off distance of less than 12 single nucleotide polymorphisms between isolates showed 19 isolates in 6 clusters (clustering rate 29.2%), located mainly in the region of the capital city of Prague. This study highlights the utility of WGS as a high-resolution approach in the diagnosis, characterization of resistance patterns, and molecular-epidemiological analysis of resistant TB in the country.

Topics: Antitubercular Agents; Czech Republic; Drug Resistance, Multiple, Bacterial; Genotype; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Phylogeny; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant; Whole Genome Sequencing

Topics: Antitubercular Agents; Humans; India; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Treatment options for children with Rifampicin-resistant tuberculosis (RR-TB) remain limited, and para-aminosalicylic acid (PAS) is still a relevant component of treatment regimens. Prevention of resistance to companion drugs by PAS is dose related, and at higher concentrations, PAS may exhibit significant bactericidal activity in addition to its bacteriostatic properties. The optimal dosing of PAS in children is uncertain, specifically for delayed-release granule preparations, which are the most used. A population pharmacokinetic model was developed describing PAS pharmacokinetics in children receiving routine RR-TB treatment. Model-based simulations evaluated current World Health Organization (WHO) weight-band doses against the adult pharmacokinetic target of 50 to 100 mg/liter for peak concentrations. Of 27 children included, the median (range) age and weight were 3.87 (0.58 to 13.7) years and 13.3 (7.15 to 30.5) kg, respectively; 4 (14.8%) were HIV positive. PAS followed one-compartment kinetics with first-order elimination and transit compartment absorption. The typical clearance in a 13-kg child was 9.79 liters/h. Increased PAS clearance was observed in both pharmacokinetic profiles from the only patient receiving efavirenz. No effect of renal function, sex, ethnicity, nutritional status, HIV status, antiretrovirals (lamivudine, abacavir, and lopinavir-ritonavir), or RR-TB drugs was detected. In simulations, target concentrations were achieved only using the higher WHO dose range of 300 mg/kg once daily. A transit compartment adequately describes absorption for the slow-release PAS formulation. Children should be dosed at the higher range of current WHO-recommended PAS doses and in a once-daily dose to optimize treatment.

Topics: Adult; Aminosalicylic Acid; Antitubercular Agents; Child; Drug Administration Schedule; HIV Infections; Humans; Rifampin; Tuberculosis, Multidrug-Resistant

There is a need for short and safe all-oral treatment of rifampicin-resistant tuberculosis. We compared outcomes up to 24 months after treatment initiation for patients with rifampicin-resistant tuberculosis in South Africa treated with a short, all-oral bedaquiline-containing regimen (bedaquiline group), or a short, injectable-containing regimen (injectable group).. Patients with rifampicin-resistant tuberculosis, aged 18 years or older, eligible for a short regimen starting treatment between Jan 1 and Dec 31, 2017, with a bedaquiline-containing or WHO recommended injectable-containing treatment regimen of 9-12 months, registered in the drug-resistant tuberculosis database (EDRWeb), and with known age, sex, HIV status, and national identification number were eligible for study inclusion; patients receiving linezolid, carbapenems, terizidone or cycloserine, delamanid, or para-aminosalicylic acid were excluded. Bedaquiline was given at a dose of 400 mg once daily for two weeks followed by 200 mg three times a week for 22 weeks. To compare regimens, patients were exactly matched on HIV and ART status, previous tuberculosis treatment history, and baseline acid-fast bacilli smear and culture result, while propensity score matched on age, sex, province of treatment, and isoniazid-susceptibility status. We did binomial linear regression to estimate adjusted risk differences (aRD) and 95% CIs for 24-month outcomes, which included: treatment success (ie, cure or treatment completion without evidence of recurrence) versus all other outcomes, survival versus death, disease free survival versus survival with treatment failure or recurrence, and loss to follow-up versus all other outcomes.. Overall, 1387 (14%) of 10152 patients with rifampicin-resistant tuberculosis treated during 2017 met inclusion criteria; 688 in the bedaquiline group and 699 in the injectable group. Four patients (1%) had treatment failure or recurrence, 44 (6%) were lost to follow-up, and 162 (24%) died in the bedaquiline group, compared with 17 (2%), 87 (12%), and 199 (28%), respectively, in the injectable group. In adjusted analyses, treatment success was 14% (95% CI 8-20) higher in the bedaquiline group than in the injectable group (70% vs 57%); loss to follow-up was 4% (1-8) lower in the bedaquiline group (6% vs 12%); and disease-free survival was 2% (0-5) higher in the bedaquiline group (99% vs 97%). The bedaquiline group had 8% (4-11) lower risk of mortality during treatment (17·0% vs 22·4%), but there was no difference in mortality post-treatment.. Patients in the bedaquiline group experienced significantly higher rates of treatment success at 24 months. This finding supports the use of short bedaquiline-containing regimens in eligible patients.. WHO Global TB Programme.. For the French translation of the abstract see Supplementary Materials section.

Topics: Antitubercular Agents; Diarylquinolines; HIV Infections; Humans; Retrospective Studies; Rifampin; South Africa; Treatment Outcome; Tuberculosis, Multidrug-Resistant

We aimed to explore the effect of pregnancy on bedaquiline pharmacokinetics (PK) and describe bedaquiline exposure in the breast milk of mothers treated for rifampicin-resistant tuberculosis (TB), where there are no human data available.. We performed a longitudinal PK study in pregnant women treated for rifampicin-resistant TB to explore the effect of pregnancy on bedaquiline exposure. Pharmacokinetic sampling was performed at 4 time-points over 6 hours in the third trimester, and again at approximately 6 weeks postpartum. We obtained serial breast milk samples from breastfeeding mothers, and a single plasma sample taken from breastfed and nonbreastfed infants to assess bedaquiline exposure. We used liquid chromatography-tandem mass spectrometry to perform the breast milk and plasma bedaquiline assays, and population PK modelling to interpret the bedaquiline concentrations.. We recruited 13 women, 6 of whom completed the ante- and postpartum PK sampling. All participants were HIV-positive on antiretroviral therapy. We observed lower ante- and postpartum bedaquiline exposures than reported in nonpregnant controls. Bedaquiline concentrations in breast milk were higher than maternal plasma (milk to maternal plasma ratio: 14:1). A single random plasma bedaquiline and M2 concentration was available in 4 infants (median age: 6.5 wk): concentrations in the 1 breastfed infant were similar to maternal plasma concentrations; concentrations in the 3 nonbreastfed infants were detectable but lower than maternal plasma concentrations.. We report low exposure of bedaquiline in pregnant women treated for rifampicin-resistant TB. Bedaquiline significantly accumulates in breast milk; breastfed infants receive mg/kg doses of bedaquiline equivalent to maternal doses.

Topics: Breast Feeding; Child; Diarylquinolines; Female; Humans; Infant; Milk, Human; Pregnancy; Rifampin; Tuberculosis, Multidrug-Resistant

Multidrug-resistant Mycobacterium tuberculosis (MDR-TB) is one of the leading causes of death in the world. The resource constraints make it difficult to diagnose and monitor the cases of MDR-TB. GeneXpert is a recognized tool used to diagnose the patients of pulmonary tuberculosis in clinical settings across the globe.. The present one-year cross-sectional study was conducted to estimate the occurrence of MDR-TB in patients with pulmonary TB. A total of 1000 patients suspected of pulmonary tuberculosis were included in this study. A random convenient sampling technique was done to collect the sputum samples (twice) from the patients. Samples were processed for the detection of Mycobacterium tuberculosis using conventional detection methods like the Ziehl Nelson staining method and fluorescent microscopy. Additionally, Cepheid GeneXpert was used for molecular detection of MDR-TB in smear-positive samples of pulmonary tuberculosis by amplifying the rifampicin resistance determining region (RRDR; rpoB gene). All the tests were performed in the biosafety level III lab of District Headquarters Hospital Nankana Sahib.. It was observed that 103 (10.3%) individuals were diagnosed as positive for tuberculosis among 1000 patients. Among these 103 TB positive cases, there were 11 (10.7%) patients diagnosed with rifampicin resistance gene (RR-Gene) of Mycobacterium tuberculosis.. Overall findings of the study showed that MDR-TB is prevalent in pulmonary TB patients and GeneXpert is the most sensitive technique for early diagnosis of the disease, which may be very helpful in the treatment and control of this public health menace in low and middle-income countries.

Topics: Antitubercular Agents; Cross-Sectional Studies; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Sputum; Tuberculosis, Lymph Node; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Uganda remains one of the countries with the highest burden of TB/HIV. Drug-resistant TB remains a substantial challenge to TB control globally and requires new strategic effective control approaches. Drug resistance usually develops due to inadequate management of TB patients including improper treatment regimens and failure to complete the treatment course which may be due to an unstable supply or a lack of access to treatment, as well as patient noncompliance.. Two sputa samples were collected from Xpert MTB/RIF® assay-diagnosed multi-drug resistant tuberculosis (MDR-TB) patient at Lira regional referral hospital in northern Uganda between 2020 and 2021 for comprehensive routine mycobacterial species identification and drug susceptibility testing using culture-based methods. Detection of drug resistance-conferring genes was subsequently performed using whole-genome sequencing with Illumina MiSeq platform at the TB Supranational Reference Laboratory in Uganda.. In both isolates, extensively drug-resistant TB (XDR-TB) was identified including resistance to Isoniazid (katG p.Ser315Thr), Rifampicin (rpoB p.Ser450Leu), Moxifloxacin (gyrA p.Asp94Gly), Bedaquiline (Rv0678 Glu49fs), Clofazimine (Rv0678 Glu49fs), Linezolid (rplC Cys154Arg), and Ethionamide (ethA c.477del). Further analysis of these two high quality genomes revealed that this 32 years-old patient was infected with the Latin American Mediterranean TB strain (LAM).. This is the first identification of extensively drug-resistant Mycobacterium tuberculosis clinical isolates with bedaquiline, linezolid and clofazimine resistance from Uganda. These acquired resistances were because of non-adherence as seen in the patient's clinical history. Our study also strongly highlights the importance of combating DR-TB in Africa through implementing next generation sequencing that can test resistance to all drugs while providing a faster turnaround time. This can facilitate timely clinical decisions in managing MDR-TB patients with non-adherence or lost to follow-up.

Topics: Adult; Antitubercular Agents; Clofazimine; Diarylquinolines; Extensively Drug-Resistant Tuberculosis; Humans; Linezolid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant; Uganda

Estimates suggest that at least 30 000 children develop multidrug-resistant or rifampicin-resistant tuberculosis each year. Despite household contact management (HCM) being widely recommended, it is rarely done.. We used mathematical modelling to evaluate the potential country-level and global effects and cost-effectiveness of multidrug-resistant or rifampicin-resistant tuberculosis HCM for children younger than 15 years who are living with a person with newly diagnosed multidrug-resistant or rifampicin-resistant tuberculosis. We compared a baseline of no HCM with several HCM strategies and tuberculosis preventive therapy regimens, calculating the effect on multidrug-resistant or rifampicin-resistant tuberculosis cases, deaths, and health-system costs. All HCM strategies involved the screening of children for prevalent tuberculosis disease but with tuberculosis preventive therapy either not given or targeted dependent on age, HIV status, and result of tuberculin skin test. We evaluated the use of fluoroquinolones (ie, levofloxacin and moxifloxacin), delamanid, and bedaquiline as tuberculosis preventive therapy.. Compared with a baseline without HCM, HCM for all adults diagnosed with multidrug-resistant or rifampicin-resistant tuberculosis in 2019 would have entailed screening 227 000 children (95% uncertainty interval [UI]: 205 000-252 000) younger than 15 years globally, and averted 2350 tuberculosis deaths (1940-2790), costing an additional US$63 million (74-95 million). If all the children within the household who had been in contact with the person with multidrug-resistant or rifampicin-resistant tuberculosis received tuberculosis preventive therapy with levofloxacin, 5620 incident tuberculosis cases (95% UI 4540-6890) and an additional 1240 deaths (970-1540) would have been prevented. Incremental cost-effectiveness ratios were lower than half of per-capita gross domestic product for most interventions in most countries. Targeting only children younger than 5 years and those living with HIV reduced the number of incident cases and deaths averted, but improved cost-effectiveness. Tuberculosis preventive therapy with delamanid increased the effect, in terms of reduced incidence and mortality, compared with levofloxacin.. HCM for patients with multidrug-resistant or rifampicin-resistant tuberculosis is cost-effective in most settings and could avert a substantial proportion of multidrug-resistant or rifampicin-resistant tuberculosis cases and deaths in children globally.. UK Medical Research Council.

Topics: Adult; Antitubercular Agents; Child; HIV Infections; Humans; Levofloxacin; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

We compared mortality between HIV-positive and HIV-negative South African adults with drug-resistant tuberculosis (DR-TB) and high incidence of acquired second-line drug resistance.. We performed a retrospective review of DR-TB patients with serial second-line TB drug susceptibility tests (2008-2015) who were hospitalized at a specialized TB hospital. We used Kaplan-Meier analysis and Cox models to examine associations with mortality.. Of 245 patients, the median age was 33 years, 54% were male and 40% were HIV-positive, 96% of whom had ever received antiretroviral therapy (ART). At initial drug resistance detection, 99% of patients had resistance to at least rifampicin and isoniazid, and 18% had second-line drug resistance (fluoroquinolones and/or injectable drugs). At later testing, 88% of patients had acquired additional second-line drug resistance. Patient-initiated treatment interruptions (> 2 months) occurred in 47%. Mortality was 79%. Those with HIV had a shorter time to death (p = 0.02; log-rank): median survival time from DR-TB treatment initiation was 2.44 years [95% confidence interval (CI): 2.09-3.15] versus 3.99 years (95% CI: 3.12-4.75) for HIV-negative patients. HIV-positive patients who received ART within 6 months before DR-TB treatment had a higher mortality hazard than HIV-negative patients [adjusted hazard ratio (aHR) ratio = 1.82, 95% CI: 1.21-2.74]. By contrast, HIV-positive patients who did not receive ART within 6 months before DR-TB treatment did not have a significantly higher mortality hazard than HIV-negative patients (aHR = 1.09; 95% CI: 0.72-1.65), although those on ART had lower median CD4 counts than those not on ART (157 vs. 281 cells/μL, respectively; p = 0.02).. A very high incidence of acquired second-line drug resistance and high overall mortality were observed, reinforcing the need to reduce the risk of acquired resistance and for more effective treatment.

Topics: Adult; Antitubercular Agents; Drug Resistance; Female; Fluoroquinolones; HIV Infections; Humans; Isoniazid; Male; Prevalence; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant

The drug resistance and influencing factors of patients with pulmonary tuberculosis were investigated, and a dual attention dilated residual network (DADRN) algorithm was proposed. The algorithm was applied to process and analyze lung computed tomography (CT) images of 400 included patients with pulmonary tuberculosis. Besides, sparse code book algorithm and bag of visual word (BOVW) algorithms were introduced and compared, and the influencing factors of pulmonary tuberculosis drug resistance were analyzed. The results demonstrated that the localization precision of lung consolidation, nodules, and cavities by the DADRN algorithm reached 91.2%, 92.5%, and 93.8%, respectively. The recall rate of the three algorithms amounted to 83.55%, 84.5%, and 86.4%, respectively. Both localization precision and recall rate of the DADRN algorithm were higher than those of other two algorithms (

Topics: Adult; Algorithms; Antitubercular Agents; Humans; Intelligence; Isoniazid; Lung; Middle Aged; Rifampin; Streptomycin; Tomography, X-Ray Computed; Tuberculosis; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Topics: DNA; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Defining the precise relationship between resistance mutations and quantitative phenotypic drug susceptibility testing will increase the value of whole-genome sequencing (WGS) for predicting tuberculosis drug resistance. However, a large number of WGS data sets currently lack corresponding quantitative phenotypic data-the MICs. Using MYCOTBI plates, we determined the MICs to nine antituberculosis drugs for 154 clinical multidrug-resistant tuberculosis isolates from the Shenzhen Center for Chronic Disease Control in Shenzhen, China. Comparing MICs with predicted drug-resistance profiles inferred by WGS showed that WGS could predict the levels of resistance to isoniazid, rifampicin, streptomycin, fluoroquinolones, and aminoglycosides. We also found some mutations that may not be associated with drug resistance, such as EmbB D328G, mutations in the

Topics: Aminoglycosides; Antitubercular Agents; Bacterial Proteins; Drug Resistance, Multiple, Bacterial; Fluoroquinolones; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifabutin; Rifampin; Streptomycin; Tuberculosis, Multidrug-Resistant

Results from the STREAM stage 1 trial showed that a 9-month regimen for patients with rifampicin-resistant tuberculosis was non-inferior to the 20-month regimen recommended by the 2011 WHO treatment guidelines. Similar levels of severe adverse events were reported on both regimens suggesting the need for further research to optimise treatment. Stage 2 of STREAM evaluates two additional short-course regimens, both of which include bedaquiline. Throughout stage 2 of STREAM, new drug choices and a rapidly changing treatment landscape have necessitated changes to the trial's design to ensure it remains ethical and relevant. This paper describes changes to the trial design to ensure that stage 2 continues to answer important questions. These changes include the early closure to recruitment of two trial arms and an adjustment to the definition of the primary endpoint. If the STREAM experimental regimens are shown to be non-inferior or superior to the stage 1 study regimen, this would represent an important contribution to evidence about potentially more tolerable and more efficacious MDR-TB regimens, and a welcome advance for patients with rifampicin-resistant tuberculosis and tuberculosis control programmes globally.Trial registration: ISRCTN ISRCTN18148631 . Registered 10 February 2016.

Topics: Antitubercular Agents; Clinical Protocols; Equivalence Trials as Topic; Humans; Randomized Controlled Trials as Topic; Rifampin; Tuberculosis, Multidrug-Resistant

Drug-resistant

Topics: Adolescent; Adult; Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Ethambutol; Humans; Iraq; Isoniazid; Mycobacterium tuberculosis; Prevalence; Rifampin; Streptomycin; Tuberculosis; Tuberculosis, Multidrug-Resistant; Young Adult

Assessing associated factors of pretreatment attrition and treatment delays among rifampicin-resistant tuberculosis (RR-TB) patients could serve as a valuable tool to control and prevent its community spread. We assessed the factors associated with pretreatment attrition and treatment initiation delays among RR-TB patients in Lagos, Nigeria.. A retrospective cohort study was conducted involving secondary program data of RR-TB patients diagnosed using the Xpert MTB/RIF assay and initiated on treatment between 1 January 2015 and 31 December 2017 in Lagos. Factors associated with pretreatment attrition and treatment initiation delay were determined using logistic regression.. Of the 606 RR-TB patients diagnosed during the review period, 135 (22.3%) had pretreatment attrition. Previously treated TB patients had a 2.4-fold greater chance of having pretreatment attrition than new RR-TB patients (adjusted odds ratio 2.4 [95% confidence interval 1.2-5.0]). The median time to treatment initiation was 29 d (interquartile range [IQR] 18-49). It was longer for new RR-TB patients (49 d [IQR 36-59]) than previously treated TB patients (28 d [IQR 17-44]). A total of 47% had long treatment delays. Being newly diagnosed with RR-TB was associated with long treatment delays.. The pretreatment attrition rate and proportion of RR-TB patients with treatment delays were high. Pragmatic approaches to address the high pretreatment attrition and treatment delays in Lagos, Nigeria, are urgently needed.

Topics: Antibiotics, Antitubercular; Humans; Mycobacterium tuberculosis; Nigeria; Retrospective Studies; Rifampin; Time-to-Treatment; Tuberculosis, Multidrug-Resistant

Type 2 diabetes mellitus (T2DM) has been associated with treatment failure, and the development of drug resistance in tuberculosis (TB). Also, whole-genome sequencing has provided a better understanding and allowed the growth of knowledge about polymorphisms in genes associated with drug resistance. Considering the above, this study analyzes genome sequences to evaluate the influence of type 2 diabetes mellitus in the development of mutations related to tuberculosis drug resistance. M. tuberculosis isolates from individuals with (n = 74), and without (n = 74) type 2 diabetes mellitus was recovered from online repositories, and further analyzed.. The results showed the presence of 431 SNPs with similar proportions between diabetics, and non-diabetics individuals (48% vs. 52%), but with no significant relationship. A greater number of mutations associated with rifampicin resistance was observed in the T2DM-TB individuals (23.2% vs. 16%), and the exclusive presence of rpoBQ432L, rpoBQ432P, rpoBS441L, and rpoBH445L variants. While these variants are not private to T2DM-TB cases they are globally rare highlighting a potential role of T2DM. The phylogenetic analysis showed 12 sublineages, being 4.1.1.3, and 4.1.2.1 the most prevalent in T2DM-TB individuals but not differing from those most prevalent in their geographic location. Four clonal complexes were found, however, no significant relationship with T2DM was observed. Samples size and potential sampling biases prevented us to look for significant associations.. The occurrence of globally rare rifampicin variants identified only in isolates from individuals with T2DM could be due to the hyperglycemic environment within the host. Therefore, further studies about the dynamics of SNPs' generation associated with antibiotic resistance in patients with diabetes mellitus are necessary.

Topics: Antitubercular Agents; Diabetes Mellitus, Type 2; Drug Resistance, Multiple, Bacterial; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Phylogeny; Polymorphism, Single Nucleotide; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant; Whole Genome Sequencing

Growing prevalence of multidrug-resistant/Rifampicin-resistant tuberculosis (MDR/RR-TB; resistance to Isoniazid and Rifampicin/Isolated resistance to Rifampicin) is putting in jeopardy the WHO End TB strategy. This study aimed to identify factors contributing to the high prevalence of MDR/RR-TB in Khabarovsk krai region of Russia.. A cross-sectional retrospective study was conducted, analyzing clinical, demographic, and drug susceptibility testing data on 1440 patients. As a source of raw data, the national electronic TB surveillance system was used. Anonymous data was collected on every patient diagnosed with TB in all healthcare facilities of the region from January 2018 to December 2019. Only patients with proven excretion of m. tuberculosis were included in the study. Factors associated with MDR/RR-TB were identified through logistic regression analysis, in conjunction with in-depth interviews with eight patients, five healthcare managers and five doctors.. 2661 patients were identified with TB, 1440 were incorporated in the study based on inclusion criteria. Of these, 618 (42.9%) were identified with MDR/RR-TB. Patients with a history of imprisonment were 16.53 times (95% CI 5.37 to 50.88,) more likely to have MDR/RR-TB, whereas re-treatment patients were 2.82 times (95% CI 2.16 to 3.66) more likely to have MDR/RR-TB. Other influencing factors included presence of disability (AOR is 2.32, 95% CI 1.38 to 3.89), cavitary disease (AOR is 1.76, 95% CI 1.37 to 2.25), and retirement status (AOR 0.65, 95% CI 0.43 to 0.98, p = 0.042). Poor patient knowledge and understanding of the disease, progressive weariness of prolonged TB treatment, and inability hospitalize infectious patients without their consent were perceived by the interviewees as major influencing factors.. Incarceration and treatment history, regardless of outcome, were identified as major factors influencing MDR/RR-TB prevalence. It is essential for the TB care system to eliminate legal loopholes, which deprive doctors of means to enforce quarantine procedures and epidemiological surveillance on infected patients, former and current inmates. Increasing people's awareness of TB, early detection and appropriate treatment of patients with TB are needed for successfully combating MDR/RR-TB.

Topics: Antitubercular Agents; Cross-Sectional Studies; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Prevalence; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant

Nowadays, pathogenic infection has posed a severe threat to the public health and environmental sanitation, urging a continuous search of efficacious and safe bactericidal agents of various formulated forms. Here, a facile one-pot hydrothermal preparation of mesoporous silica nanoparticles using ultrasonication-assisted nanoemulsion of α-Linolenic acid (α-LA) as template was developed. The formed silica mesocomposite at water/fatty-acid surface provides an easy yet green synthesis route, which can be generalized for the further encapsulation of hydrophobic drugs such as antimycobacterial Rifampicin (RIF). The obtained α-LA nanoemulsion-templated silica nanoparticles (LNS NPs), with a weight content of ∼17% α-LA in the composite, showed apparent antibacterial effect against Staphylococcus aureus (S. aureus). By comparison, the removal of α-LA from the silica nanoparticles (LNS-1 NPs) resulted in the composite of enlarged pore size with negligible bactericidal activities. Notably, the Isoniazide (INH) and Rifampicin (RIF)-encapsulated LNS NPs exhibited outstanding antimycobacterial activity against both drug-sensitive and drug-resistant Mycobacterium tuberculosis (M. tuberculosis). The obtained highly biocompatible, biosafe and low-energy consumptive α-LA-contained mesostructured silica-based bactericide holds promising therapeutic potentials to tackle the emerging drug-resistant infectious microbes.

Topics: alpha-Linolenic Acid; Anti-Bacterial Agents; Humans; Mycobacterium tuberculosis; Nanoparticles; Rifampin; Silicon Dioxide; Staphylococcus aureus; Tuberculosis, Multidrug-Resistant

The effective management of multidrug-resistant tuberculosis (MDR-TB) and the need for rapid and accurate screening of rifampin (RIF) and isoniazid (INH)-resistant Mycobacterium tuberculosis (Mtb) isolates are the most fundamental and difficult challenges facing the global TB control. The present study aimed to compare the diagnostic accuracy of high-resolution melting-curve analysis (HRMA) in comparison to multiplex allele-specific PCR (MAS-PCR) and xpert MTB/RIF as well as the conventional drug-susceptibility test (DST) and gene sequencing for the detection of INH and RIF resistance in the Mtb isolates. In the present study, a total of 431 Mtb isolates including 11 MDR (%2.55), 7 INH resistance (%1.62), two RIF resistance (%0.46), and 411 sensitive isolates were phenotypically confirmed. HRMA assay identified katG gene mutations and the mabA-inhA promoter region in 15 of 18 INH-resistant samples and rpoB gene mutations were successfully evaluated in 11 out of 13 RIF-resistant samples. The sensitivity and specificity of the HRMA method were 83.3% and 98.8% for INH and 84.6% and 99% for RIF, respectively. The most common mutation in RIF-resistance-determining region (RRDR) occurred at codon 531 (TCG → TTG)(84.6%) and then at codon 513 (CAA → GTA)(7.6%) and 526 (CAC → TAC) (7.6%), which resulted in the amino-acid changes. Also, 88.8% of INH-resistant samples had mutations in the katG gene and the mabA-inhA promoter region, of which the highest mutation occurred at codon 315 (AGC → ACC) of the katG gene. In conclusion, all these results indicated that the sensitivity and specificity of the HRM method were increased when the katG gene and the mabA-inhA promoter region were used as a target.

Topics: Antitubercular Agents; Bacterial Proteins; Codon; Humans; Isoniazid; Microbial Sensitivity Tests; Multiplex Polymerase Chain Reaction; Mutation; Mycobacterium tuberculosis; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant

GeneXpert MTB/RIF is a reliable molecular diagnostic tool capable of detecting Mycobacterium tuberculosis (MTB) and identifying genetic determinants of rifampicin (RIF) resistance. This study aimed to assess physicians' diagnostic decision-making processes for TB based on GeneXpert MTB/RIF results and how this affected the initiation of multidrug resistance (MDR) treatment. This study employed a mixed method: data were collected retrospectively from the medical records of TB patients and in-depth interviews were conducted with healthcare workers in areas with a high TB burden in Thailand. A total of 2,030 complete TB records from 2 patient groups were reviewed, including 1443 suspected cases with negative smear results and 587 with high risk of MDR-TB. GeneXpert MTB/RIF was routinely used to assist the physicians in their decision-making for the diagnosis of pulmonary tuberculosis (PTB) and the initiation of MDR-TB treatment. The physicians used it as a "rule-in test" for all patients with negative chest X-rays (CXR) and smear results, to ensure timely treatment. Approximately one-fourth of the patients with negative CXR/smear and GeneXpert MTB/RIF results were diagnosed with PTB by the physicians, who based their decisions on other evidence, such as clinical symptoms, and did not use GeneXpert MTB/RIF as a "rule-out test." GeneXpert MTB/RIF proved effective in early detection within a day, thereby radically shortening the time required to initiate second-line drug treatment. Despite its high sensitivity for detecting PTB and MDR-TB, GeneXpert MTB/RIF had contradictory results (false positive and/or false negative) for 21.8% of cases among patients with negative smear results and 41.1% of cases among patients with high risk of MDR-TB. Therefore, physicians still used the results of other conventional tests in their decision-making process. It is recommended that GeneXpert MTB/RIF should be established at all points of care and be used as the initial test for PTB and MDR-TB diagnosis.

Topics: Humans; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Sensitivity and Specificity; Sputum; Thailand; Tuberculosis, Lymph Node; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Topics: Antitubercular Agents; Humans; Male; Recurrence; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Whole-genome sequencing (WGS) of Mycobacterium tuberculosis complex has become an important tool in diagnosis and management of drug-resistant tuberculosis. However, data correlating resistance genotype with quantitative phenotypic antimicrobial susceptibility testing (AST) are scarce.. In a prospective multicentre observational study, 900 clinical M tuberculosis complex isolates were collected from adults with drug-resistant tuberculosis in five high-endemic tuberculosis settings around the world (Georgia, Moldova, Peru, South Africa, and Viet Nam) between Dec 5, 2014, and Dec 12, 2017. Minimum inhibitory concentrations (MICs) and resulting binary phenotypic AST results for up to nine antituberculosis drugs were determined and correlated with resistance-conferring mutations identified by WGS.. Considering WHO-endorsed critical concentrations as reference, WGS had high accuracy for prediction of resistance to isoniazid (sensitivity 98·8% [95% CI 98·5-99·0]; specificity 96·6% [95% CI 95·2-97·9]), levofloxacin (sensitivity 94·8% [93·3-97·6]; specificity 97·1% [96·7-97·6]), kanamycin (sensitivity 96·1% [95·4-96·8]; specificity 95·0% [94·4-95·7]), amikacin (sensitivity 97·2% [96·4-98·1]; specificity 98·6% [98·3-98·9]), and capreomycin (sensitivity 93·1% [90·0-96·3]; specificity 98·3% [98·0-98·7]). For rifampicin, pyrazinamide, and ethambutol, the specificity of resistance prediction was suboptimal (64·0% [61·0-67·1], 83·8% [81·0-86·5], and 40·1% [37·4-42·9], respectively). Specificity for rifampicin increased to 83·9% when borderline mutations with MICs overlapping with the critical concentration were excluded. Consequently, we highlighted mutations in M tuberculosis complex isolates that are often falsely identified as susceptible by phenotypic AST, and we identified potential novel resistance-conferring mutations.. The combined analysis of mutations and quantitative phenotypes shows the potential of WGS to produce a refined interpretation of resistance, which is needed for individualised therapy, and eventually could allow differential drug dosing. However, variability of MIC data for some M tuberculosis complex isolates carrying identical mutations also reveals limitations of our understanding of the genotype and phenotype relationships (eg, including epistasis and strain genetic background).. Bill & Melinda Gates Foundation, German Centre for Infection Research, German Research Foundation, Excellence Cluster Precision Medicine of Inflammation (EXC 2167), and Leibniz ScienceCampus EvoLUNG.

Topics: Antitubercular Agents; Genomics; Humans; Mycobacterium tuberculosis; Phenotype; Prospective Studies; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Drug resistance in Mycobacterium tuberculosis (MTB) has long been a serious health issue worldwide. Most drug-resistant MTB isolates were identified due to treatment failure or in clinical examinations 3~6 months postinfection. In this study, we propose a whole-genome sequencing (WGS) pipeline via the Nanopore MinION platform to facilitate the efficacy of phenotypic identification of clinical isolates. We used the Nanopore MinION platform to perform WGS of clinical MTB isolates, including susceptible (

Topics: Antitubercular Agents; Bacterial Proteins; DNA-Directed RNA Polymerases; Drug Resistance, Bacterial; Humans; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifabutin; Rifampin; Tuberculosis, Multidrug-Resistant

TBI-166, derived from riminophenazine analogues, shows more potent anti-TB activity than clofazimine and is being assessed against tuberculosis (TB) in a phase IIa clinical trial in China. Preclinical regimen studies containing TBI-166 will support the phase IIb clinical trials of TBI-166. In the present study, we compared the efficacy in three murine TB models of an all-oral drug-resistant TB drug regimen of TBI-166 with bedaquiline (BDQ) and pyrazinamide (PZA) with the first-line regimen of isoniazid (INH) with rifampin (RFP) and PZA (HRZ regimen), the most effective reported TBI-166-containing regimen of TBI-166 with BDQ and linezolid (LZD), and the Nix-TB clinical trial regimen of BDQ with pretomanid and LZD (BPaL regimen). In the C3HeB/FeJ murine TB model, for the TBI-166+BDQ+PZA regimen, the lungs of mice were culture negative at 4 weeks, and there were no relapses at 8 weeks of treatment. The reduction in bacterial burden and relapse rate were greater than those of the HRZ regimen and the TBI-166+BDQ+LZD regimen. Compared with the BPaL regimen, the TBI-166+BDQ+PZA regimen had similar or stronger early bactericidal activity, bactericidal activity, and sterilizing activity in the BALB/c murine TB model. The bacterial burden in the TBI-166+BDQ+PZA regimen group decreased significantly more than that in the BPaL regimen group and was almost or totally relapse free (<13.33% after 8 weeks). In conclusion, oral short-course three-drug regimens, including TBI-166 with high efficacy, were identified. The TBI-166+BDQ+PZA regimen is recommended for further study in a TBI-166 phase IIb clinical trial.

Topics: Animals; Antitubercular Agents; Clofazimine; Diarylquinolines; Disease Models, Animal; Isoniazid; Linezolid; Mice; Mice, Inbred BALB C; Mycobacterium tuberculosis; Pyrazinamide; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Ethiopia is one of the high multidrug-resistant tuberculosis (MDR-TB) burden countries. However, phenotypic drug susceptibility testing can take several weeks due to the slow growth of Mycobacterium tuberculosis complex (MTBC) strains. In this study, we assessed the performance of a Sanger sequencing approach to predict resistance against five anti-tuberculosis drugs and the pattern of resistance mediating mutations.. We enrolled 226 MTBC culture-positive MDR-TB suspects and collected sputum specimens and socio-demographic and TB related data from each suspect between June 2015 and December 2016 in Addis Ababa, Ethiopia. Phenotypic drug susceptibility testing (pDST) for rifampicin, isoniazid, pyrazinamide, ethambutol, and streptomycin using BACTEC MGIT 960 was compared with the results of a Sanger sequencing analysis of seven resistance determining regions in the genes rpoB, katG, fabG-inhA, pncA, embB, rpsL, and rrs.. DNA isolation for Sanger sequencing was successfully extracted from 92.5% (209/226) of the MTBC positive cultures, and the remaining 7.5% (17/226) strains were excluded from the final analysis. Based on pDST results, drug resistance proportions were as follows: isoniazid: 109/209 (52.2%), streptomycin: 93/209 (44.5%), rifampicin: 88/209 (42.1%), ethambutol: 74/209 (35.4%), and pyrazinamide: 69/209 (33.0%). Resistance against isoniazid was mainly mediated by the mutation katG S315T (97/209, 46.4%) and resistance against rifampicin by rpoB S531L (58/209, 27.8%). The dominating resistance-conferring mutations for ethambutol, streptomycin, and pyrazinamide affected codon 306 in embB (48/209, 21.1%), codon 88 in rpsL (43/209, 20.6%), and codon 65 in pncA (19/209, 9.1%), respectively. We observed a high agreement between phenotypic and genotypic DST, such as 89.9% (at 95% confidence interval [CI], 84.2%-95.8%) for isoniazid, 95.5% (95% CI, 91.2%-99.8%) for rifampicin, 98.6% (95% CI, 95.9-100%) for ethambutol, 91.3% (95% CI, 84.6-98.1%) for pyrazinamide and 57.0% (95% CI, 46.9%-67.1%) for streptomycin.. We detected canonical mutations implicated in resistance to rifampicin, isoniazid, pyrazinamide, ethambutol, and streptomycin. High agreement with phenotypic DST results for all drugs renders Sanger sequencing promising to be performed as a complementary measure to routine phenotypic DST in Ethiopia. Sanger sequencing directly from sputum may accelerate accurate clinical decision-making in the future.

Topics: Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Ethambutol; Ethiopia; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Pyrazinamide; Rifampin; Streptomycin; Tuberculosis, Multidrug-Resistant

The Comprehensive Resistance Prediction for Tuberculosis: an International Consortium (CRyPTIC) presents here a data compendium of 12,289 Mycobacterium tuberculosis global clinical isolates, all of which have undergone whole-genome sequencing and have had their minimum inhibitory concentrations to 13 antitubercular drugs measured in a single assay. It is the largest matched phenotypic and genotypic dataset for M. tuberculosis to date. Here, we provide a summary detailing the breadth of data collected, along with a description of how the isolates were selected, collected, and uniformly processed in CRyPTIC partner laboratories across 23 countries. The compendium contains 6,814 isolates resistant to at least 1 drug, including 2,129 samples that fully satisfy the clinical definitions of rifampicin resistant (RR), multidrug resistant (MDR), pre-extensively drug resistant (pre-XDR), or extensively drug resistant (XDR). The data are enriched for rare resistance-associated variants, and the current limits of genotypic prediction of resistance status (sensitive/resistant) are presented by using a genetic mutation catalogue, along with the presence of suspected resistance-conferring mutations for isolates resistant to the newly introduced drugs bedaquiline, clofazimine, delamanid, and linezolid. Finally, a case study of rifampicin monoresistance demonstrates how this compendium could be used to advance our genetic understanding of rare resistance phenotypes. The data compendium is fully open source and it is hoped that it will facilitate and inspire future research for years to come.

Topics: Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Extensively Drug-Resistant Tuberculosis; Humans; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Phenotype; Rifampin; Tuberculosis, Multidrug-Resistant

The AID line probe assay has shown promising evaluation data on the detection of Mycobacterium tuberculosis as well as 1st- and 2nd-line drug resistance, using isolates and selected clinical samples in previous studies.. The diagnostic performance of three AID-modules (AID INH/RIF, AID FQ/EMB and AID AG) was analyzed in sputum samples from patients with presumed tuberculosis against culture methods and phenotypic drug resistance as reference standards.. 59 patients had culture-confirmed tuberculosis. All AID modules showed moderate sensitivity (46/59, 78.0%, 65.3-87.7) and very good specificity (100%, 95.5%, 93.7%). There was a high proportion of invalid tests, resulting in 32.6%, 78.3% and 19.6% of 46 AID-positive tuberculosis cases, who could not be assessed for drug resistance by the AID INH/RIF-, AID FQ/EM- and AID AG-module, respectively. A small number of patients showed drug resistance by reference standards: Three MDR-TB cases plus three, one and one patients with resistance to streptomycin, fluoroquinolones and aminoglycosides, respectively. The AID-assay detected all MDR-TB cases, two of three streptomycin-resistant TB cases, one of one of fluoroquinolone-resistant and missed one aminoglycoside-resistant TB case.. The high proportion of invalid results precludes the use of the AID-assay from direct sputum-based tuberculosis and drug-resistance testing.

Topics: Antitubercular Agents; Drug Resistance; Fluoroquinolones; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Romania; Streptomycin; Tuberculosis, Lymph Node; Tuberculosis, Multidrug-Resistant

The World Health Organization (WHO) recently revised its guidelines for rapid diagnosis of drug-resistant tuberculosis (TB). This study aimed to investigate if TB reference diagnostic services are prepared to support these revisions. An online survey was performed among 44 TB National Reference Laboratories (NRLs) in the WHO European Region. Questions addressed the use of WHO-recommended molecular techniques for the diagnosis of drug-resistant TB, the techniques applied to investigate antimicrobial resistance, and questions on quality assurance. Among 35 of 44 (80%) participating NRLs, 29 of 35 (83%) reported using the GeneXpert platform as the initial test to detect Mycobacterium tuberculosis complex and rifampicin resistance. Five laboratories reported using another WHO-recommended, moderate-complexity, automated nucleic acid amplification test for detection of Mycobacterium tuberculosis complex and resistance to rifampicin and isoniazid. Most (32 of 35; 91%) NRLs reported the capacity to test second-line drugs that have been in clinical use for many years (fluoroquinolones, linezolid, and injectable agents). Only 23 of 35 (66%) and 21 of 35 (60%) NRLs reported the capacity to test bedaquiline and clofazimine. Further efforts will be needed to improve the availability of quality-controlled testing against WHO Group A and Group B drugs. Earlier considerations on the scale-up of diagnostic capacities should be enforced as part of future approval processes for new antimycobacterial agents.

Topics: Antitubercular Agents; Humans; Linezolid; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant; World Health Organization

In 2018, the World Health Organization recommended a 6-month four-drug regimen (rifampicin, ethambutol, pyrazinamide, and levofloxacin) for the treatment of isoniazid-monoresistant tuberculosis. However, the regimen had very low certainty. This cohort study assessed the impact of fluoroquinolone use and initial baseline regimen on treatment effectiveness in isoniazid-monoresistant tuberculosis. This multicenter retrospective cohort study included 318 patients with isoniazid-monoresistant tuberculosis notified between 2011 and 2018 in Korea. Baseline regimens were classified into two groups, namely 6-9-month rifampicin, ethambutol, and pyrazinamide (6-9REZ) and a combination regimen of 2-month rifampicin, ethambutol, pyrazinamide and 7-10-month rifampicin and ethambutol (2REZ/7-10RE). Multivariable logistic regression was performed to assess factors associated with positive treatment outcomes. Of 318 enrolled patients, 234 (73.6%) were treated with the 6-9REZ and 103 (32.4%) with additional fluoroquinolone. In a multivariable logistic regression model comparing the 6-9REZ and 2REZ/7-10RE groups, there was no difference in the odds of positive outcomes (adjusted odds ratio = 1.08, 95% confidence interval = 0.65-1.82). Addition use of fluoroquinolone was not associated with positive treatment outcomes in the whole cohort (adjusted odds ratio = 1.41, 95% confidence interval = 0.87-2.27); however, its additional use was beneficial in the 2REZ/7-10RE subgroup (adjusted odds ratio = 3.58, 95% confidence interval = 1.32-9.75). Both initial baseline regimens, 6-9REZ and 2REZ/7-10RE, were similarly effective. Shortening of the pyrazinamide administration duration with additional fluoroquinolone use could be a safe alternative for patients with potential hepatotoxicity related to pyrazinamide.

Topics: Antitubercular Agents; Cohort Studies; Drug Therapy, Combination; Ethambutol; Fluoroquinolones; Humans; Isoniazid; Pyrazinamide; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant

As one of the top three high tuberculosis (TB) burden countries, China is a country where the overall TB incidence continues to decline. However, due to its large population and area, the increased TB burden exists in regional areas.. This retrospective study analyzed local inpatient pulmonary TB cases in the Affiliated Hospital of Zunyi Medical University (AHZMU) from January 2016 to December 2018 in a high TB incidence and economically-less-developed area of China. Four methods, acid-fast bacilli stain, culture, Xpert and LAMP, were used to detect. Total 3,910 local inpatient cases with pulmonary TB were admitted to AHZMU during this study period. The annual numbers of total TB cases increased 26.4% (from 1,173 to 1,483), while new cases increased 29.6% (from 936 to 1,213) and RR-TB cases increased 2.7 times (from 31 to 84). Meanwhile, the percentage of previously treated cases declined from 20.2 to 18.2% and the. The elevated

Topics: Humans; Inpatients; Retrospective Studies; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Topics: Antitubercular Agents; Extensively Drug-Resistant Tuberculosis; Fluoroquinolones; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Tuberculosis (TB) is a communicable, preventable and curable disease caused by the bacterium Mycobacterium tuberculosis (MTB). Peru is amongst the 30 countries with the highest burden of multidrug-resistant tuberculosis (MDR-TB) worldwide. In the fight against drug-resistant tuberculosis, the UKMYC6 microdilution plate was developed and validated by the CRyPTIC project. The objective of the study was to evaluate the use of the broth microdilution (BMD) plate methodology for susceptibility testing of drug-resistant MTB strains in Peru.. MTB strains isolated between 2015 and 2018 in Peru were used. 496 nationally-representative strains determined as drug-resistant by the routine 7H10 Agar Proportion Method (APM) were included in the present study. The Minimum Inhibitory Concentration (MIC) of 13 antituberculosis drugs were determined for each strain using the UKMYC6 microdilution plates. Diagnostic agreement between APM and BMD plate methodology was determined for rifampicin, isoniazid, ethambutol, ethionamide, kanamycin and levofloxacin. Phenotypes were set using binary (or ternary) classification based on Epidemiological cut-off values (ECOFF/ECV) proposed by the CRyPTIC project. Whole Genome Sequencing (WGS) was performed on strains with discrepant results between both methods.. MIC distributions were determined for 13 first- and second-line anti-TB drugs, including new (bedaquiline, delamanid) and repurposed (clofazimine, linezolid) agents. MIC results were available for 80% (397/496) of the strains at 14 days and the remainder at 21 days. The comparative analysis determined a good agreement (0.64 ≤ k ≤ 0.79) for the drugs rifampicin, ethambutol, ethionamide and kanamycin, and the best agreement (k > 0.8) for isoniazid and levofloxacin. Overall, 12% of MIC values were above the UKMYC6 plate dilution ranges, most notably for the drugs rifampicin and rifabutin. No strain presented MICs higher than the ECOFF/ECV values for the new or repurposed drugs. Discrepant analysis using genotypic susceptibility testing by WGS supported half of the results obtained by APM (52%, 93/179) and half of those obtained by BMD plate methodology (48%, 86/179).. The BMD methodology using the UKMYC6 plate allows the complete susceptibility characterization, through the determination of MICs, of drug-resistant MTB strains in Peru. This methodology shows good diagnostic performances for rifampicin, isoniazid, ethambutol, ethionamide, kanamycin and levofloxacin. It also allows for the characterization of MICs for other drugs used in previous years against tuberculosis, as well as for new and repurposed drugs recently introduced worldwide.

Topics: Antitubercular Agents; Ethambutol; Ethionamide; Humans; Isoniazid; Kanamycin; Levofloxacin; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Peru; Rifampin; Tuberculosis, Lymph Node; Tuberculosis, Multidrug-Resistant

Refractory rifampicin-resistant/multidrug resistant/extensively-drug resistant tuberculosis (RR/MDR/XDR-TB) were defined as patients infected with Mycobacterium tuberculosis (MTB) resistant to rifampicin(RR-TB), or at least resistant to rifampicin and isoniazid (MDR-TB) or added resistant to fluoroquinolones (FQs) and one of second line injectable agents (XDR-TB), a patient for whom an effective regimen (fewer than 4 effective agents due to adverse events (AEs) or multiple drug resistances) cannot be developed. To compare the effectiveness and safety of bedaquiline (BDQ)-containing and BDQ-free regimens for treatment of patients with refractory RR/MDR/XDR-TB.. Patients with refractory RR/MDR/XDR-TB receiving BDQ-containing regimens (BDQ group, n = 102) and BDQ-free regimens (non-BDQ group, n = 100) satisfied with included criteria were strictly included in this retrospective historical control study across East China. Culture conversion, treatment outcome, cavity closing rate, and AEs were compared between two groups.. The baseline characteristics involved all possible aspects of patients were well balanced between two groups (p > 0.05). Culture conversion rates in the BDQ group at month 3 (89.2% vs. 66.0%), month 6 (90.2% vs 72.0%), month 9 (91.2% vs. 66.0%), and month 12 (94.1% vs 65.0%) were all significantly higher than those in non-BDQ group (p < 0.001). Similar results were observed in the cavity closing rate at month 9 (19.6% vs 8.0%, p = 0.0) and month 12 (39.2% vs 15.0%, p < 0.001). Patients receiving BDQ-containing regimens had more treatment success than those receiving BDQ-free regimens (p < 0.001; cure rate, 69.6% vs. 45.0%; complete the treatment, 22.5% vs. 18.0%; treatment success, 92.2% vs. 63.0%); the use of BDQ and combined with Linezolid or Clofazimine or Cycloserine were identified as independent predictors of treatment success and no culture reversion (P < 0.05). AEs were similarly reported in 26.5% of patients in the BDQ group and 19.0% in the non-BDQ group (p = 0.2).. BDQ-containing regimens resulted in better treatment outcomes and similar safety relative to BDQ-free regimens for patients with refractory pulmonary RR/MDR/XDR-TB.

Topics: Antitubercular Agents; Diarylquinolines; Extensively Drug-Resistant Tuberculosis; Humans; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

The transmission of drug-resistant tuberculosis is one of the greatest challenges facing the global tuberculosis control.. The aim of the study was to investigate the resent transmission of rifampicin resistant tuberculosis in Bulgaria and to describe the mutations related to the antimicrobials' resistance using whole genome sequencing.. As part of an ECDC funded pilot study for evaluation of the systematic use of whole genome sequencing (WGS) of Mycobacterium tuberculosis (MTB) surveillance (EUSeqMyTB), Bulgaria provided 65 rifampicin resistant isolates over a three years' timeframe (2017-2019) representing 87.5% of the notified rifampicin resistant cases. Drug resistance prediction and relatedness analysis of the resistant isolates was performed in collaboration with San Raffaele Scientific Institute, Milan, Italy.. Almost all of the isolates were identified as Euro-American lineage (96.9%); 18.5% of the isolates were found to be resistant to fluoroquinolones, but no mutations conferring resistance to bedaquiline or linezolid could be identified. Less than half (43.3%) of the isolates were clustered (<5 SNPs distance) into a total of seven national SNP-based clusters, while a total of six isolates were found to be part of different cross-border clusters. All clustered cases originated from Bulgaria.. WGS has proven to be a reliable tool for surveillance and tracing of recent transmission of tuberculosis and has the potential for resistance prediction for most of the antituberculosis drugs.

Topics: Antitubercular Agents; Bulgaria; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Pilot Projects; Rifampin; Tuberculosis, Multidrug-Resistant; Whole Genome Sequencing

The objective was to determine the molecular epidemiology and drug susceptibility patterns of Mycobacterium tuberculosis (MTB) of children and their household contacts (HHC) in Umlazi, a high TB-burden township in South Africa. Sixty eight MTBRifPLUS positive TB-infected children (TIC) (≤14 years) and 111 HHC were enrolled. Drug susceptibility testing (DST) was performed on sputum samples using the proportion method and GenoType® MTBDR. Genotyping of MTB was conducted using IS6110-restriction fragment length polymorphism (RFLP) and spoligotyping. Rifampicin (RIF) susceptibility was observed in 67/68 TIC. GenoType® MTBDRplus and phenotypic DST identified drug resistant strains in five of 16 culture-confirmed TIC. The Beijing strain was identified in six and the F15/LAM4/KZN strain in one of the 13 TIC respectively. Four patients with unknown RFLP strains belonged to spoligoclades S, T1, T3 variant and X2. The S-lineage and an unknown strain were identified in two HHC. MDR-TB and pre-XDR-TB were identified in one HHC each. Household transmission could not be determined as none of the culture-confirmed TIC resided with the six culture-confirmed contacts. The predominance of the hypervirulent Beijing strain and presence of drug-resistant strains must be considered in the implementation of effective TB control strategies and development of efficacious vaccines.

Topics: Antitubercular Agents; Beijing; Child; Genotype; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; South Africa; Tuberculosis, Lymph Node; Tuberculosis, Multidrug-Resistant

A total of 302. The magnitude of MDR

Topics: Antitubercular Agents; Drug Resistance; Ethiopia; Genotype; Humans; Mycobacterium tuberculosis; Rifampin; Somalia; Tuberculosis, Multidrug-Resistant

Controlling drug-resistant. Whole-genome sequencing (WGS) has not been employed to comprehensively study. Drug resistance was predicted by WGS in a "TB-Profiler" web service after phenotypic drug susceptibility tests (DSTs) against nine anti-TB drugs among 59 clinical isolates. A comparison of consistency, sensitivity, specificity, and positive and negative predictive values between WGS and DST were carried out for each drug.. The sensitivities and specificities for WGS were 95.92 and 90% for isoniazid (INH), 100 and 64.1% for ethambutol (EMB), 97.37 and 100% for streptomycin (SM), 75 and 100% for amikacin (AM), 80 and 96.3%for capreomycin (CAP), 100 and 97.22% for levofloxacin (LFX), 93.33 and 90.91% for prothionamide (PTO), and 70 and 97.96% for para-aminosalicylic acid (PAS). Around 53 (89.83%) and 6 (10.17%) of the isolates belonged to lineage two (East-Asian) and lineage four (Euro-American), respectively.. Whole-genome sequencing is a reliable method for predicting resistance to INH, RIF, EMB, SM, AM, CAP, LFX, PTO, and PAS with high consistency, sensitivity, and specificity. There was no transmission that occurred among the patients with RR-TB in Ningbo, China.

Topics: Antitubercular Agents; Drug Resistance; Ethambutol; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

To determine the levels and patterns of resistance to first- and second-line anti-tuberculosis (TB) drugs among new and previously treated sputum smear positive pulmonary TB (PTB) patients.. We conducted a nationally representative cross-sectional facility-based survey in June 2017-July 2018 involving 45 clusters selected based on probability proportional to size. The survey aimed to determine the prevalence of anti-TB drug resistance and associated risk factors among smear positive PTB patients in Tanzania. Sputum samples were examined using smear microscopy, Xpert MTB/RIF, culture and drug susceptibility testing (DST). Logistic regression was used to account for missing data and sampling design effects on the estimates and their standard errors.. We enrolled 1557 TB patients, including 1408 (90.4%) newly diagnosed and 149 (9.6%) previously treated patients. The prevalence of multidrug-resistant TB (MDR-TB) was 0.85% [95% confidence interval (CI): 0.4-1.3] among new cases and 4.6% (95% CI: 1.1-8.2) among previously treated cases. The prevalence of Mycobacterium tuberculosis strains resistant to any of the four first-line anti-TB drugs (isoniazid, rifampicin, streptomycin and ethambutol) was 1.7% among new TB patients and 6.5% among those previously treated. Drug resistance to all first-line drugs was similar (0.1%) in new and previously treated patients. None of the isolates displayed poly-resistance or extensively drug-resistant TB (XDR-TB). The only risk factor for MDR-TB was history of previous TB treatment (odds ratio = 5.7, 95% CI: 1.9-17.2).. The burden of MDR-TB in the country was relatively low with no evidence of XDR-TB. Given the overall small number of MDR-TB cases in this survey, it will be beneficial focusing efforts on intensified case detection including universal DST.

Topics: Antitubercular Agents; Cross-Sectional Studies; Ethambutol; Extensively Drug-Resistant Tuberculosis; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Streptomycin; Tanzania; Tuberculosis, Multidrug-Resistant

Traditionally, single critical concentrations of drugs are utilized for Mycobacterium tuberculosis (Mtb) drug susceptibility testing (DST); however, the level of drug resistance can impact treatment choices and outcomes. Mutations at the katG gene are the major genetic mutations in multidrug resistant (MDR) Mtb and usually associated with high level resistance. We assessed the minimum inhibitory concentrations (MICs) of MDR or rifampin resistant (RR) and isoniazid (INH) resistant Mtb isolates to determine the quantification of drug resistance among key anti-tuberculosis drugs.. The study was conducted on stored Mtb isolates collected as part of a national drug resistance survey in Ethiopia. MIC values were determined using Sensititre™ MYCOTB plates. A line probe assay (MTBDRplus) was also performed to identify genetic determinants of resistance for all isolates.. MIC testing was performed on 74 Mtb isolates including 46 MDR, 2 RR and 26 INH phenotypically resistant isolates as determined by the Löwenstein Jensen (LJ) method. Four (15%) INH resistant Mtb isolates were detected as borderline rifampin resistance (MIC = 1 μg/ml) using MYCOTB MIC plates and no rifampin resistance mutations were detected by LPA. Among the 48 MDR/RR TB cases, 9 (19%) were rifabutin susceptible (MIC was between ≤0.25 and 0.5μg/ml). Additionally, the MIC for isoniazid was between 2-4 μg/ml (moderate resistance) for 58% of MDR TB isolates and 95.6% (n = 25) of the isolates had mutations at the katG gene.. Our findings suggest a role for rifabutin treatment in a subset of RR TB patients, thus potentially preserving an important drug class. The high proportion of moderate level INH resistant among MDR Mtb isolates indicates the potential benefit of high dose isoniazid treatment in a high proportion of katG gene harboring MDR Mtb isolates.

Topics: Ethiopia; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifabutin; Rifampin; Tuberculosis, Multidrug-Resistant

Hepatocellular injury has been reported commonly in adults on rifampicin-resistant and multidrug-resistant tuberculosis (RR/MDR-TB) treatment. However, there are limited data in children.. Two pharmacokinetic studies of children (0-17 years) routinely treated for RR/MDR-TB were conducted in Cape Town, South Africa between October 2011 and February 2020. Hepatocellular injury adverse events (AEs; defined as elevated alanine aminotransferase [ALT]) were documented serially. Data were analyzed to determine the incidence, etiology, risk factors, management and outcome of ALT elevation.. A total of 217 children, median age 3.6 years (interquartile range, 1.7-7.1 years) at enrollment were included. The median follow-up time was 14.0 months (interquartile range, 9.8-17.2 months). Fifty-five (25.3%) patients developed an ALT AE. Of these, 43 of 55 (78%) patients had 54 ALT AEs attributed to their RR/MDR-TB treatment. The incidence rate of ALT AEs related to RR-TB treatment was 22.4 per 100 person-years. Positive HIV status and having an elevated ALT at enrollment were associated with time to ALT AE attributed to RR/MDR-TB treatment, with P values 0.0427 and P < 0.0001, respectively. Hepatitis A IgM was positive in 11 of 14 (78.6%) severe (grade ≥3) cases of ALT AEs. In 8 of 14 (57%) severe ALT AEs, hepatotoxic drugs were stopped or temporarily interrupted. None had a fatal or unresolved outcome.. Hepatocellular injury in children on RR/MDR-TB treatment is common, although usually mild; having elevated ALT early in treatment and HIV-positive status are possible risk factors. Hepatitis A was a common etiology of severe ALT AE in children treated for RR/MDR-TB.

Topics: Adult; Antitubercular Agents; Carcinoma, Hepatocellular; Child; Child, Preschool; Hepatitis A; Humans; Incidence; Liver Neoplasms; Rifampin; South Africa; Treatment Outcome; Tuberculosis, Multidrug-Resistant

To describe treatment outcomes for rifampicin-resistant tuberculosis (Rr-TB) started on standard regimen and the frequency of acquired drug resistance in patients treated using the standard treatment regimen (STR) in Cameroon between 2015-2019.. This is a retrospective cohort study. Rr-TB patients were initiated on the STR, including a fluoroquinolone (FQ), a second-line injectable drug (SLI), and companion drugs. In case of resistance to fluoroquinolones (FQr) at baseline, FQ, SLI and ethionamide were replaced by bedaquiline, delamanid, and linezolid in a modified treatment regimen (mTR), FQr-mTR. In case of resistance to SLI (SLIr) at baseline, SLI was replaced by linezolid (LZD), SLIr-mTR. Logistic regression and competing risk regression were used to estimate predictors of early (first eight weeks) mortality and overall mortality, respectively.. Of 709 patients started on a standard regimen, treatment success occurred in 84.7% (587/693), 72.7% (8/11) and 100% (10/10) of patients treated with STR, FQr-mTR and SLIr-mTR as final regimens, respectively. Three (0.6%) patients acquired FQr during treatment. Early mortality occurred in 4.1% (29/709) and was associated with being HIV positive, male sex and being underweight. Overall mortality was associated with missing drug-susceptibility testing results at baseline, being HIV positive, age>40 and male sex.. Programmatic management of Rr-TB, with additional second-line drug resistance treated with mTR, resulted in excellent treatment outcomes.

Topics: Adult; Antitubercular Agents; Cameroon; Fluoroquinolones; HIV Infections; Humans; Linezolid; Male; Retrospective Studies; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Humans; Rifampin; Tuberculosis, Multidrug-Resistant

Mycobacterium tuberculosis strains with phenotypically susceptible rpoB mutations (rifampicin discordant) have emerged following implementation of rapid molecular drug resistance testing for tuberculosis. Whilst rifampicin resistance is known to be associated with resistance to other rifamycins (rifapentine and rifabutin) as well as isoniazid and pyrazinamide, rifampicin discordant strains have shown high rates of susceptibility to isoniazid and rifabutin. However, pyrazinamide susceptibly testing results have not been reported.. We evaluated pyrazinamide resistance in 80 rifampicin discordant and 25 rifampicin and isoniazid susceptible isolates from KwaZulu-Natal in South Africa using Mycobacteria Growth Indicator Tube method and sequencing of the pncA. We also compared susceptibility of pyrazinamide with that of isoniazid.. Pyrazinamide resistance was found in 6/80 (7.5%) rifampicin discordant isolates. All pyrazinamide resistant isolates were also resistant to isoniazid and pyrazinamide resistance was found to be associated with isoniazid resistance. No pyrazinamide resistance was found among the isoniazid susceptible isolates.. Given the low prevalence of pyrazinamide resistance in rifampicin discordant TB, this anti-TB drug still has a significant role in the treatment of these patients. Performing pyrazinamide susceptibility testing remains a challenge, our findings show that isoniazid susceptible isolates are unlikely to be resistant to pyrazinamide among the discordant TB isolates.

Topics: Antitubercular Agents; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Pyrazinamide; Rifabutin; Rifampin; South Africa; Tuberculosis; Tuberculosis, Multidrug-Resistant

Multidrug-resistant (MDR) tuberculosis (TB) is defined by the resistance of Mycobacterium tuberculosis, the causative organism, to the first-line antibiotics rifampicin and isoniazid. Mitigating or reversing resistance to these drugs offers a means of preserving and extending their use in TB treatment. R-loops are RNA/DNA hybrids that are formed in the genome during transcription, and they can be lethal to the cell if not resolved. RNase HI is an enzyme that removes R-loops, and this activity is essential in M. tuberculosis: knockouts of

Topics: Anti-Bacterial Agents; Antitubercular Agents; Cell Death; Humans; Isoniazid; Moxifloxacin; Mycobacterium Infections; Mycobacterium tuberculosis; Rifampin; RNA; Streptomycin; Tuberculosis, Multidrug-Resistant

Several studies described the presence of non-replicating, drug-tolerant differentially culturable tubercle bacteria (DCTB) in sputum from patients with active tuberculosis (TB). These organisms are unable to form colonies on agar but can be recovered in liquid media supplemented with culture filtrate as a source of growth factors. Herein, we undertook to investigate the response of DCTB during the treatment of individuals with drug-resistant TB. A cohort of 100 participants diagnosed with rifampicin-resistant TB were enrolled and prospectively followed to monitor response to therapy using routine culture and limiting dilution assays, supplemented with culture filtrate (CF) to quantify DCTB. Fifteen participants were excluded due to contamination, and of the remaining 85 participants, 29, 49, and 7 were infected with rifampicin mono-resistant (RMR), multidrug-resistant (MDR), or extremely drug-resistant (XDR) TB, respectively. Analysis of baseline sputum demonstrated that CF supplementation of limiting dilution assays detected notable amounts of DCTB. Prevalence of DCTB was not influenced by smear status or mycobacterial growth indicator tube time to positivity. CF devoid of resuscitation promoting factors (Rpfs) yielded a greater amount of DCTB in sputum from participants with MDR-TB compared with those with RMR-TB. A similar effect was noted in DCTB assays without CF supplementation, suggesting that CF is dispensable for the detection of DCTB from drug-resistant strains. The HIV status of participants, and CD4 count, did not affect the amount of DCTB recovered. During treatment with second-line drug regimens, the probability of detecting DCTB from sputum specimens in liquid media with or without CF was higher compared with colony forming units, with DCTB detected up to 16 weeks post treatment. Collectively, these data point to differences in the ability of drug-resistant strains to respond to CF and Rpfs. Our findings demonstrate the possible utility of DCTB assays to diagnose and monitor treatment response for drug-resistant TB, particularly in immune compromised individuals with low CD4 counts.

Topics: Agar; Antitubercular Agents; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant

Topics: Adolescent; Adult; Antitubercular Agents; Caregivers; Child; Cross-Sectional Studies; Family Characteristics; Female; Humans; Male; Rifampin; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Child; Humans; Nitroimidazoles; Oxazoles; Rifampin; Tuberculosis, Multidrug-Resistant

Namibia is among 30 countries with a high burden of tuberculosis (TB), with an estimated incidence of 460 per 100,000 population and around 800 new multidrug-resistant (MDR) TB cases per year. Still, data on the transmission and evolution of drug-resistant Mycobacterium tuberculosis complex (Mtbc) strains are not available. Whole-genome sequencing data of 136 rifampicin-resistant (RIFr) Mtbc strains obtained from 2016 to 2018 were used for phylogenetic classification, resistance prediction, and cluster analysis and linked with phenotypic drug susceptibility testing (pDST) data. Roughly 50% of the strains investigated were resistant to all first-line drugs. Furthermore, 13% of the MDR Mtbc strains were already pre-extensively drug resistant (pre-XDR). The cluster rates were high, at 74.6% among MDR and 85% among pre-XDR strains. A significant proportion of strains had borderline resistance-conferring mutations, e.g.,

Topics: Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Humans; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Namibia; Phylogeny; Rifampin; Tuberculosis, Multidrug-Resistant

Tuberculosis (TB) often concentrates in groups of people with complex health and social issues, including alcohol use disorders (AUD). Risk of TB, and poor TB treatment outcomes, are substantially elevated in people who have AUD. Médecins sans Frontières and the Belarus Ministry of Health have worked to improve treatment adherence in patients with multi-drug or rifampicin resistant (MDR/RR)-TB and harmful use of alcohol. In 2016, a person-centred, multidisciplinary, psychosocial support and harm reduction programme delivered by TB doctors, counsellors, psychiatrists, health-educators, and social workers was initiated. In 2020, we described patient and provider experiences within the programme as part of a wider evaluation.. We recruited 12 patients and 20 health-care workers, using purposive sampling, for in-depth individual interviews and focus group discussions. We used a participant-led, flexible, exploratory approach, enabling participants and the interviewer to shape topics of conversation. Qualitative data were coded manually and analysed thematically. As part of the analysis process, identified themes were shared with health-care worker participants to enable their reflections to be incorporated into the findings.. Key themes related to the patients' and practitioners experience of having and treating MDRTB with associated complex health and social issues were: fragility and despair and guidance, trust and health. Prejudice and marginalisation were global to both themes. Counsellors and other health workers built a trusting relationship with patients, enabling guidance through a multi-disciplinary approach, which supported patients to achieve their vision of health. This guidance was achieved by a team of social workers, counsellors, doctors and health-educators who provided professional and individualised help for patients' illnesses, personal or interpersonal problems, administrative tasks, and job searches.. Patients with MDR/RR-TB and harmful use of alcohol faced complex issues during treatment. Our findings describe how person-centred, multi-disciplinary, psychosocial support helped patients in this setting to cope with these challenges and complete the treatment programme. We recommend that these findings are used to: i) inform programmatic changes to further boost the person-centred care nature of this program; and ii) advocate for this type of person-centred care approach to be rolled out across Belarus, and in contexts that face similar challenges.

Topics: Alcoholism; Antitubercular Agents; Harm Reduction; Humans; Psychosocial Support Systems; Qualitative Research; Republic of Belarus; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Fluoroquinolones (FQs) are the most important second-line anti-tuberculosis (anti-TB) drugs, primarily used for the treatment of multidrug- or rifampicin-resistant TB (MDR/RR-TB). However, FQs are also commonly used to treat other bacterial infections. There are few published data on the rates of FQ resistance among rifampicin-susceptible TB.. We used whole-genome sequencing (WGS) to determine the prevalence of FQ resistance among rifampicin-susceptible TB in a rural district of Shanghai. This was a population-based retrospective study of all culture-positive pulmonary TB patients diagnosed in the Chongming district of Shanghai, China during 2009-2018.. The rate of FQ resistance was 8.4% (29/345) among TB, 6.2% (20/324) among rifampicin-susceptible TB, and 42.9% (9/21) among MDR/RR-TB. Transmission of FQ-resistant strains was defined as strains differing within 12 single-nucleotide polymorphisms (SNPs) based on WGS. Among the rifampicin-susceptible TB, 20% (4/20) of FQ resistance was caused by the transmission of FQ-resistant strains and 45% (9/20) of FQ resistance was identified as hetero-resistance.. The prevalence of FQ resistance in rifampicin-susceptible TB was higher than expected in Shanghai. Both the transmission and the selection of drug-resistant strains drive the emergence of FQ resistance in rifampicin-susceptible TB isolates. Therefore, the WGS-based surveillance system for TB should be urgently established and the clinical awareness of the rational use of FQs for respiratory infections should be enhanced to prevent the premature occurrence of FQ resistance.

Topics: Antitubercular Agents; China; Fluoroquinolones; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant

Globally, the emergence of multidrug-resistant strains of Mycobacterium tuberculosis is an increasing problem that adversely affects patient care and public health. This cross sectional descriptive study was carried out in the Department of Microbiology, Mymensingh Medical College from January 2010 to December 2010 to isolate M. tuberculosis from smear-positive sputum samples by Lowenstein-Jensen (L-J) media and investigate the drug resistance pattern. Among 101 smear-positive cases 80(79.20%) yielded growth of Mycobacteria, 5(4.95%) were contaminated and 16(15.84%) showed no growth. Among 80 isolates 76(95.0%) were M. tuberculosis and the remaining 4(5.0%) were Non-tuberculous Mycobacteria (NTM). Out of 76 M. tuberculosis 27(35.52%) were resistant to at least one drug, 4(5.26%) to Isoniazid (INH), 1(1.32%) to Rifampicin (RMP), 8(10.53%) to Streptomycin (SM) and 0(0.0%) to Ethambutol (EMB) and multi-drug resistant tuberculosis (MDR-TB) was 9(11.84%). The present study creates the impression that fairly high rate of anti-tuberculosis drug resistance among the tuberculosis cases and also high MDR-TB (Resistant to both Rifampicin and Isoniazide). The emergence of MDR-TB poses significant trouble to TB control activities throughout the world. The complexity of MDR-TB operation makes it essential to produce new skills to design, plan, application and monitor interventions for the management of MDR-TB. More surveillance and immediate remedial interventions should be performed to combat the trouble of MDR-TB to the general population.

Topics: Antitubercular Agents; Bangladesh; Cross-Sectional Studies; Drug Resistance; Ethambutol; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Streptomycin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Topics: Aged; Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Fluoroquinolones; Genotype; Humans; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Phylogeny; Rifampin; Tuberculosis, Multidrug-Resistant

Targeted next-generation sequencing (tNGS) has emerged as an alternative method for detecting drug-resistant tuberculosis (DR-TB). To provide comprehensive drug susceptibility information and to address mutations missed by available commercial molecular diagnostics, we developed and evaluated a tNGS panel with 22 whole-gene targets using the Ion Torrent platform to predict drug resistance to 14 drugs, namely, rifampicin (RIF), isoniazid (INH), ethambutol (EMB), pyrazinamide (PZA), moxifloxacin (MFX), levofloxacin (LFX), amikacin (AMK), capreomycin (CM), kanamycin (KM), streptomycin (SM), bedaquiline (BDQ), clofazimine (CFZ), linezolid (LZD), and delamanid (DLM). We selected 50 and 35 Mycobacterium tuberculosis isolates with various DR profiles as the training set and the challenge set, respectively. Comparative variant analyses of the DR genes were performed using Sanger sequencing and whole-genome sequencing (WGS). Phenotypic drug susceptibility testing (pDST) results were used as gold standards. Regarding the limit of detection, the tNGS assay detected 2.9 to 3.8% minority variants in 4% mutant mixtures. The sensitivity and specificity of tNGS were 97.0% (95% confidence interval [CI] = 93.1 to 98.7%) and 99.1% (95% CI = 97.7 to 99.7%), respectively. The concordance of tNGS with pDST was 98.5% (95% CI = 97.2 to 99.2%), which was comparable to that of WGS (98.7%, 95% CI = 97.4 to 99.3%) and better than that of Sanger sequencing (96.9%, 95% CI = 95.3 to 98.0%). The agreement between tNGS and pDST was almost perfect for RIF, INH, EMB, MFX, LFX, AMK, CM, KM, SM, BDQ, and LZD (kappa value = 0.807 to 1.000) and substantial for PZA (kappa value = 0.791). Our customized novel whole-gene-based tNGS panel is highly consistent with pDST and WGS for comprehensive and accurate prediction of drug resistance in a strengthened and streamlined DR-TB laboratory program.

Topics: Amikacin; Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Ethambutol; High-Throughput Nucleotide Sequencing; Humans; Levofloxacin; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Early detection of Mycobacterium tuberculosis (Mtb) in clinical specimens, its susceptibility to anti-TB drugs and disruption of infection transmission to new hosts are essential components for global tuberculosis (TB) control efforts. This study investigated major Mtb genotypes circulating in Kuwait and evaluated the performance of REBA MTB-MDR (REBA) test in comparison to GenoType MTBDRplus (gMTBDR+) assay for rapid detection of resistance of Mtb to isoniazid and rifampicin (MDR-TB). M. tuberculosis isolates (n = 256) originating predominantly from expatriate patients during a 6-month period were tested by spoligotyping and a dendrogram was created by UPGMA using MIRU-VNTRplus software. Phenotypic drug susceptibility testing (DST) was performed by MGIT 960 system. Genotypic DST for isoniazid and rifampicin was done by REBA and gMTBDR+ assays. Spoligotyping assigned 188 (73.4%) isolates to specific spoligotype international type (SIT) while 68 isolates exhibited orphan patterns. All major M. tuberculosis lineages were detected and EAI, CAS and Beijing families were predominant. Phylogenetic tree showed 131 patterns with 105 isolates exhibiting a unique pattern while 151 isolates clustered in 26 patterns. Fifteen isolates were resistant to one/more drugs. REBA and gMTBDR+ detected isoniazid resistance in 11/12 and 10/12 and rifampicin resistance in 4/5 and 4/5 resistant isolates, respectively. The diversity of SIT patterns are highly suggestive of infection of most expatriate patients with unique Mtb strains, likely acquired in their native countries before their arrival in Kuwait. Both, REBA and gMTBDR+ assays performed similarly for detection of resistance of Mtb to isoniazid and rifampicin for rapid detection of MDR-TB.

Topics: Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Genotype; Humans; Isoniazid; Kuwait; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Phylogeny; Rifampin; Tuberculosis, Lymph Node; Tuberculosis, Multidrug-Resistant

Whole-genome sequencing (WGS) of Mycobacterium tuberculosis (MTB), proven to be a better alternative when compared with the combined sensitivity and specificity of all other modalities for diagnosis of tuberculosis (TB), aids epidemiological surveillance investigations by combining the current research with diagnostics. This study was conducted to identify and resolve operational challenges in performing WGS-based drug resistance testing (DRT) for MTB in a TB culture and drug susceptibility testing (DST) laboratory. Three critical, non-redundant steps for WGS-based DRT were tested: viz. DNA extraction, high-throughput paired-end next-generation sequencing (NGS), and genomic analysis pipeline for automated reporting of WGS-based DRT.. DNA was extracted from 100 liquid culture isolates on a mycobacterial growth indicator tube (MGIT) using DNEASY Ultraclean Microbial Kit (Qiagen, USA) as per the manufacturer's instructions. Illumina paired-end sequencing was performed. All analysis steps were automated using custom python scripts, requiring no intervention. Variant calling was performed as per the World Health Organization (WHO) technical guide.. The number of cultures resistant to rifampicin, isoniazid, pyrazinamide, ethambutol, and streptomycin was 89, 88, 35, 67, and 73, respectively. Resistance to amikacin, kanamycin, and capreomycin was found in 15, 17, and 15 cultures, respectively. Seventy cultures were resistant to fluoroquinolones, four were resistant to ethionamide, and 12 were resistant to linezolid. Six cultures were resistant to only one of the 18 drugs tested. Seventy-five cultures were resistant to more than three anti-TB drugs. One culture was resistant to 13 of the 18 anti-TB drugs tested for this study. The maximum number of variants were observed in the rpoB gene (n = 93, 93%), wherein the Ser450Leu was the predominant mutation (n = 68, 73%). Ser315Thr was the most common variant (n = 86, 97%) that encoded resistance to isoniazid. The Lys43Arg variant encodes resistance to streptomycin and was the third most predominant variant (n = 65, 89%). In addition to the high levels of resistance observed in the dataset, we also observed a high proportion of Beijing strains (n = 63, 63%).. Compared with results from routine diagnostics based on the 'Guidelines on Programmatic Management of Drug-Resistant TB (PMDT) in India', none of the samples had DST available for all 18 drugs. This represents a gap in PMDT guidelines. The WGS-DRT must be considered as the primary DST method after a sample is flagged rifampicin-resistant by cartridge-based nucleic acid amplification testing (CBNAAT). With several research studies currently underway globally to identify novel variants associated with drug resistance and classifiy their minimum inhibitory coefficients, WGS-DRT presents a scalable technology that updates analytical pipelines, relegating the need for changing microbiological protocols.

Topics: Antitubercular Agents; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Streptomycin; Tertiary Healthcare; Tuberculosis, Multidrug-Resistant

Universal drug susceptibility testing (DST) for tuberculosis is a major goal of the END TB strategy. PCR-based molecular diagnostic tests have been instrumental in increasing DST globally and several assays have now been endorsed by the World Health Organization (WHO) for use in the diagnosis of drug resistance. These endorsed assays, however, each interrogate a limited number of mutations associated with resistance, potentially limiting their sensitivity compared to sequencing-based methods. We applied an in silico method to compare the sensitivity and specificity of WHO-endorsed molecular based diagnostics to the mutation set identified by the WHO mutations catalogue using phenotypic DST as the reference. We found that, in silico, the mutation sets used by probe-based molecular diagnostic tests to identify rifampicin, isoniazid, pyrazinamide, levofloxacin, moxifloxacin, amikacin, capreomycin and kanamycin resistance produced similar sensitivities and specificities to the WHO mutation catalogue. PCR-based diagnostic tests were most sensitive for drugs where mechanisms of resistance are well established and localised to small genetic regions or a few prevalent mutations. Approaches using sequencing technologies can provide advantages for drugs where our knowledge of resistance is limited, or where complex resistance signatures exist.

Topics: Amikacin; Antitubercular Agents; Capreomycin; Genotype; Humans; Isoniazid; Levofloxacin; Microbial Sensitivity Tests; Moxifloxacin; Mycobacterium tuberculosis; Pyrazinamide; Rifampin; Tuberculosis, Multidrug-Resistant; World Health Organization

In 2020 there were 623 known TB infections in the Netherlands according to the Dutch ministry of health (RIVM). About 4% were located in bones and joints. The incidence of Multi Drug Resistant (MDR) TB in The Netherlands is about 1%.. We describe the case of a 46-year-old female with a painful and swelling of the mid phalangeal bone of the fourth left digit. Quantiferon was positive and PCR of the biopsy for Mycobacterium tuberculosis complex (MTC) in Ziehl-Neelsen staining confirmed tuberculous osteomyelitis. The strain was resistant for rifampicin, isoniazid, ethambutol and pyrazinamid classifying it as MDR. Treatment in a specialized center with second line drugs was indicated due to rare resistance.. Tuberculosis may manifest anywhere throughout the body, also as an (atypical) swelling of the hand. The golden diagnostic standard for bone and joint TB is biopsy with Ziehl-Neelsen staining.

Topics: Antitubercular Agents; Ethambutol; Female; Humans; Isoniazid; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Identifying the transmission mode and resistance mechanism of Mycobacterium tuberculosis (MTB) is key to prevent disease transmission. However, there is a lack of regional data. Therefore, the aim of this study was to identify risk factors associated with the transmission of MTB and regional patterns of resistance to isoniazid (INH) and rifampicin (RFP), as well as the prevalence of multidrug-resistant tuberculosis (MDR-TB).. High-resolution melt (HRM) analysis was conducted using sputum, alveolar lavage fluid, and pleural fluid samples collected from 17,515 patients with suspected or confirmed MTB infection in the downtown area and nine counties of Luoyang City from 2019 to 2021.. Of the 17,515 patients, 82.6% resided in rural areas, and 96.0% appeared for an initial screening. The HRM positivity rate was 16.8%, with a higher rate in males than females (18.0% vs. 14.1%, p < 0.001). As expected, a positive sputum smear was correlated with a positive result for HRM analysis. By age, the highest rates of MTB infection occurred in males (22.9%) aged 26-30 years and females (28.1%) aged 21-25. The rates of resistance to RFP and INH and the incidence of MDR were higher in males than females (20.5% vs. 16.1%, p < 0.001, 15.9% vs. 12.0%, p < 0.001 and 12.9% vs. 10.2%, p < 0.001, respectively). The HRM positivity rate was much higher in previously treated patients than those newly diagnosed for MTB infection. Notably, males at the initial screening had significantly higher rates of HRM positive, INH resistance, RFP resistance, and MDR-TB than females (all, p < 0.05), but not those previously treated for MTB infection. The HRM positivity and drug resistance rates were much higher in the urban vs. rural population. By multivariate analyses, previous treatment, age < 51 years, residing in an urban area, and male sex were significantly and positively associated with drug resistance after adjusting for smear results and year of testing.. Males were at higher risks for MTB infection and drug resistance, while a younger age was associated with MTB infection, resistance to INH and RFP, and MDR-TB. Further comprehensive monitoring of resistance patterns is needed to control the spread of MTB infection and manage drug resistance locally.

Topics: Adult; Antitubercular Agents; Female; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

This study aimed to assess the time to first culture conversion and its predictors among MDR/RR-TB cases enrolled in Dilchora Hospital.. A retrospective cohort study was conducted among MDR/RR TB cases enrolled between January 2014 and December 2018. SPSS version 26 was used for analysis. Reports are presented using percentages and frequency. Independent predictors of time-to-culture conversion were identified using multivariate Cox proportional hazard regression. Adjusted and crude hazard ratio with 95% CI was used. P-value< 0.05 declared statistical significance.. A total of 145 MDR/RR TB cases were included. The median time to culture conversion was at 2 months. Higher baseline hemoglobin [AHR:1.101(1.02-1.19)] and having a non-cavitary lesion on chest x-ray[AHR:1.803(1.15-2.83)] predicted a higher likelihood of early culture conversion. Resistance to at least one first-line anti-TB drug in addition to rifampicin was associated with a lower hazard of early culture conversion as compared to only rifampicin resistance[AHR: 0.577(0.37-0.91)].. A baseline hemoglobin level, chest x-ray finding of cavitation and resistance to rifampicin, and at least one additional drug predicted the time to culture conversion. A closer treatment monitoring and follow-up should be emphasized for those presenting with lower baseline hemoglobin, more drug resistance, and cavitation on chest x-ray.

Topics: Antitubercular Agents; Humans; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Sputum; Treatment Outcome; Tuberculosis, Multidrug-Resistant

Geriatric population are predisposed to reactivation to tuberculosis (TB) and multi-drug resistance (MDR) due to deteriorated immune system. Limited data is available in this population hence present study is undertaken to study drug resistance and associated mutations among geriatric presumptive DR-TB patients by genotypic methods METHODS: From October 2011 to December 2018, demographic characteristics of enrolled patients was collected. Smear-positive processed sputum samples were subjected directly while cultures positive for Mycobacterium Tuberculosis (MTB) from smear-negative pulmonary and all extra-pulmonary samples were subjected to LPA. The LPA used were Genotype MTBDR plus (1st line LPA) for detection of susceptibility to rifampicin (RIF) and isoniazid (INH) and Genotype MTBDR sl (2nd line LPA), for susceptibility to fluoroquinolones (FQ) and aminoglycosides (AG).. Total of 2041 samples were received from presumptive MDR-TB patients above 60 years of age during study period, of which 1406; 68.9% were within 60-70 year followed by 495; 24.3% within 71-80 year and 140; 6.9% more than 80 years. Total of 1055 MTB were detected, of which those diagnosed as RIF resistant were 117/1055; 11.2% including 89/1055; 8.5% MDR-TB and resistance to INH was in 84/1055; 8%. Total 67, 2nd line LPA gave valid results, of which 19/67 (28.4%) isolates were resistant to only FQ, and one isolate was resistant to AG.. Study finding highlights need for dedicated efforts for diagnosis, and treatment of geriatric tuberculosis. Suitable intervention at programmatic country level at country will help in strengthening tuberculosis control strategies in this population.

Topics: Aged; Drug Resistance; Humans; Mutation; Referral and Consultation; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

We determined the prevalence of rifampicin resistance in pulmonary tuberculosis patients in Enugu Nigeria.. A prospective hospital-based study involving 1300 presumptive multidrug-resistant tuberculosis patients was conducted in Enugu between April 2017 and 31st March, 2019.Participants age ranged from 15 years and older and each submitted one sputum specimens Sputum specimens were analyzed using the Gene Xpert MTB/RIF assay to detect resistance to rifampicin according to manufacturer's protocol.. The prevalence of rifampicin resistant tuberculosis was 6.8% (95% CI: 5.5- 8.3). Rifampicin resistance was significantly higher in males (9.0%) than females (4.2%) (P = 0.036< 0.05). Most of the cases were seen in the age group 35-44 years (28.4%). Prevalence of rifampicin resistant tuberculosis was 2.7% in treatment naive (new) patients and 4.1% in patients on anti-tuberculosis therapy (previously treated).. The prevalence of rifampicin resistant tuberculosis in Enugu was high. Rifampicin resistance in treatment naive (new) patients was also high. This study therefore highlights that active transmission of Multidrug-resistant tuberculosis among young males could be on-going.

Topics: Adolescent; Adult; Drug Resistance, Bacterial; Female; Humans; Male; Mycobacterium tuberculosis; Nigeria; Prevalence; Prospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Consistently deciding its current extent and chance elements of tuberculosis (TB) in all levels of clinical settings contributes to the anticipation and control exertion of the disease. In Ethiopia, updated information is still needed at every healthcare level and in different risk groups to monitor the national program's performance, which aims to attain the 2035 goal. Hence, this study aimed to generate additional evidence data on the magnitude of Mycobacterium tuberculosis using the Gene Xpert assay among TB-suspected patients at Mizan-Tepi university teaching hospital, southwest Ethiopia.. A cross-sectional descriptive study was conducted from June to September 30, 2021. The required socio-demographic and other risk factor data were collected from a total of 422 suspected TB patients using a structured questionnaire. Approximately 392 pulmonary and 30 extra-pulmonary samples were collected and examined using the Gene Xpert-MTB/RIF assay. The statistical package for social sciences (SPSS) version 25 software was used to analyze the data.. In this study, Mycobacterium tuberculosis was detected in 12.5% (49/392) of pulmonary samples and 13.3% (4/30) of extra-pulmonary samples, giving an overall TB positivity of 12.6% (53/422). Rifampicin-resistant M. tuberculosis was detected in 3/53 (5.7%). Male sex (AOR: 2.54; 95% CI: 1.210, 5.354), previous contact (AOR: 4.25; 95% CI: 1.790, 10.092), smoking cigarette (AOR: 4.708; 95% CI: 1.004, 22.081), being HIV-positive (AOR: 4.27; 95% CI: 1.606, 11.344), and malnutrition (AOR: 3.55; 95% CI: 1.175, 10.747) were all significantly associated with M. tuberculosis detection using the GeneXpert MTB/RIF assay.. The overall frequency of M. tuberculosis in this study was still significant in different risk groups, despite the proposed strategies, which aimed to reduce TB prevalence to as low as 10 per 100,000 populations by 2035. Early case detection with better diagnostic tools and public health measures are important prevention and control strategies to meet the proposed target and reduce the burden of TB in the country.

Topics: Cross-Sectional Studies; Ethiopia; Hospitals, Teaching; Humans; Male; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Lymph Node; Tuberculosis, Multidrug-Resistant; Universities

Bedaquiline (BDQ) is a core drug for rifampicin-resistant tuberculosis (RR-TB) treatment. Accurate prediction of a BDQ-resistant phenotype from genomic data is not yet possible. A Bayesian method to predict BDQ resistance probability from next-generation sequencing data has been proposed as an alternative.. We performed a qualitative study to investigate the decision-making of physicians when facing different levels of BDQ resistance probability. Fourteen semi-structured interviews were conducted with physicians experienced in treating RR-TB, sampled purposefully from eight countries with varying income levels and burden of RR-TB. Five simulated patient scenarios were used as a trigger for discussion. Factors influencing the decision of physicians to prescribe BDQ at macro-, meso- and micro levels were explored using thematic analysis.. The perception and interpretation of BDQ resistance probability values varied widely between physicians. The limited availability of other RR-TB drugs and the high cost of BDQ hindered physicians from altering the BDQ-containing regimen and incorporating BDQ resistance probability in their decision-making. The little experience with BDQ susceptibility testing and whole-genome sequencing results, and the discordance between phenotypic susceptibility and resistance probability were other barriers for physicians to interpret the resistance probability estimates. Especially for BDQ resistance probabilities between 25% and 70%, physicians interpreted the resistance probability value dynamically, and other factors such as clinical and bacteriological treatment response, history of exposure to BDQ, and resistance profile were often considered more important than the BDQ probability value for the decision to continue or stop BDQ. In this grey zone, some physicians opted to continue BDQ but added other drugs to strengthen the regimen.. This study highlights the complexity of physicians' decision-making regarding the use of BDQ in RR-TB regimens for different levels of BDQ resistance probability.. Ensuring sufficient access to BDQ and companion drugs, improving knowledge of the genotype-phenotype association for BDQ resistance, availability of a rapid molecular test, building next-generation sequencing capacity, and developing a clinical decision support system incorporating BDQ resistance probability will all be essential to facilitate the implementation of BDQ resistance probability in personalizing treatment for patients with RR-TB.

Topics: Antitubercular Agents; Bayes Theorem; Decision Making; Humans; Rifampin; Tuberculosis, Multidrug-Resistant

Topics: Germany; Humans; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant; World Health Organization

Drug resistant tuberculosis (DR-TB), particularly multidrug resistance (MDR-TB) and extensive drug resistance (XDR-TB) pose a serious threat to public health. This study aimed to identify drug resistance in pulmonary tuberculosis patients and to see their association with diabetes, human immunodeficiency virus (HIV), previous history of tuberculosis (TB) and family history of TB.. Sputum specimens obtained from 11,874 pulmonary tuberculosis patients were subjected to smear microscopy, cartridge based nucleic acid amplification test (CBNAAT) and liquid culture (LC). Smear positive isolates were subjected to first line Line probe assay (FL-LPA) for isoniazid and rifampicin resistance. FL- LPA positive isolates were subjected to second line Line probe assay (SL-LPA) for fluoroquinolones and second line injectable drug resistance.. Out of 11,874 microbiologically confirmed cases of pulmonary tuberculosis, 976 (8.2%) had a drug resistant tuberculosis. Five patterns of drug resistance were identified monoisoniazid; 394 (3.32%), rifampicin; 461 (3.88%) (monorifampicin; 383 (3.22%)), multidrug; 73 (0.61), extensivedrug; 11 (0.09) and others; 37 (0.31). Previous history of tuberculosis was significantly associated with rifampicin resistance and MDR-TB. Family history of tuberculosis contact was strongly associated with rifampicin resistance, MDR-TB and XDR-TB.. There has been an increasing trend in drug resistance in the recent years, particularly in retreatment cases. This study highlights the pattern of drug resistance and need to detect resistance among all tuberculosis cases, in order to interrupt transmission and control this emerging epidemic.

Topics: Drug Resistance; Extensively Drug-Resistant Tuberculosis; Humans; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

The untested empirical medications exacerbated the development of multidrug-resistant

Topics: Antitubercular Agents; Bacterial Proteins; DNA-Directed RNA Polymerases; Humans; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Globally, TB is the leading cause of infectious disease morbidity and mortality with many diagnostic uncertainties. Access to affordable and rapid diagnostics remained a major challenge for many developing countries which bear the greatest burden of TB delaying the initiation time to treatment.. This study aimed to assess the GeneXpert MTBRIF assay probe utility for the detection of pulmonary TB and Rifampicin-resistant TB cases in Addis Ababa, Ethiopia.. A cross-sectional study was performed from October 2019 to July 2020 in Saint Peter TB Specialized Hospital in Addis Ababa metropolitan area, Ethiopia. This study enrolled 216 clinically suspected new presumptive pulmonary TB cases confirmed by GeneXpert MTB/RIF Assay. Sociodemographic and clinical characteristics were captured using a structured tool. Data were entered in Microsoft Excel 2019, checked for inconsistency, cleaned promptly, and exported to IBM SPSS Statistics for Windows, Version 26.0. Armonk, N.Y: IBM Corp, the USA for analysis. Descriptive analysis and binary and multivariate logistics regression were performed and all statistical significance was determined at a 95% confidence level.. The majority of the study participants, 55.1% [119/216] were males aged 6-80 years. The prevalence of RR MTB was 11.11% [24/216]. A higher proportion of RR TB was found in female patients [54.2%, 13/24], in patients in the age group of 30-50 years [45.8%, 11/24], in married individuals [62.5%, 15/24], in persons whose residence is urban [79.2%, 19/24], in persons who had a previous history of TB symptoms [100%, 24/24], in persons who had a history of contact with active and LTBI [33.3%, 8/24], and in persons who had a history of HIV and IDUs [41.7%, 10/24]. Occupation (AOR 22.868, 95% CI 1.655-316.022, p = 0.019), history of previous PTB+ (AOR 4.222, 95% CI 1.020-17.47, p = 0.047), and history of HIV and IDUs (AOR 4.733, 95% CI 1.416-15.819, p = 0.012) were independent predictors associated with RR-TB emergence. The commonest mutation 62.5% [15/24] was found in probe E (codons 529-533) region. There was no mutation associated with probe A (codons 507-511), probe B (codons 511-518), and probe C (codons 518-523) regions, as well as no combination of missed probes, was revealed. However, 12.5% [3/24] of RR TB patients were found without unidentified missed probe types detected outside of the RRDR. The delta Ct max was >4.0 and the highest proportion of 35.6% [77/216] RR TB was detected in samples of medium DNA load.. The proportion of RR-TB we observed in this study was high. Similarly, a higher proportion of RR TB was detected outside of the RRDR. Moreover, a significant number of the GeneXpert MTB/RIF Assay probes were identified as unhybridized and this critical observation would mean that most of the probes had no or minimal utility in this geographical region. This calls for further studies to uncover mutation in the rpoB gene conferring RR and reshape TB triage and definite diagnostic algorithm in Ethiopia.

Topics: Adult; Codon; Cross-Sectional Studies; Ethiopia; Female; HIV Infections; Humans; Male; Middle Aged; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Whole genome sequencing (WGS) is an increasingly useful tool for tuberculosis (TB) diagnosis and disease management. In this study, we evaluated the utility of user-friendly WGS tools in reporting resistance profiles and identifying lineages of clinical TB isolates from South Korea.. Forty clinical samples from TB patients showing discrepancies between their rapid molecular and conventional drug susceptibility tests were used in this study. Among these clinical isolates, 37 strains were successfully evaluated via WGS software, using the GenTB, TB Profiler, PhyResSE, CASTB, and Mykrobe.. More accurate and faster susceptibility results could be obtained with isoniazid than with rifampin. Using the phenotypic test as the gold standard, the isoniazid concordance rate between phenotypic drug susceptibility test (DST) and WGS (GenTB: 45.9%, TB profiler: 40.5%, PhyResSE: 40.5%, CASTB: 48.6%, and Mykrobe: 43.2%) was much higher than between phenotypic DST and rapid molecular genotypic DST (18.9%) among the 37 strains. In contrast, the rifampin concordance rate between phenotypic DST and WGS and that between phenotypic DST and rapid molecular genotypic DST was similar (81.1-89.2%). We also found novel mutations associated with INH in. WGS may play a pivotal role in TB diagnosis and the detection of drug resistance, genetic diversity, and transmission dynamics in the near future because of its accuracy, speed, and extensibility.

Topics: Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Software; Tuberculosis; Tuberculosis, Multidrug-Resistant; Whole Genome Sequencing

India implements universal drug susceptibility testing (UDST) using rapid genotypic tests (cartridge-based nucleic acid amplification test CBNAAT - and line probe assay - LPA). to bridge the gap of diagnosis of multidrug/rifampicin-resistant TB. There is limited evidence assessing the implementation of UDST in India. We assessed the implementation among people with pulmonary TB notified from public facilities in October 2019 from Raichur (Karnataka), India.. A cohort study involving secondary data in routine programme settings was conducted. All people with TB underwent a rapid genotypic DST for rifampicin resistance followed by first line-LPA (FL-LPA) if sensitive and second line-LPA (SL-LPA) if resistant.. Of 217 people, 15.7% (n=34) did not undergo rapid genotypic DST. Of 135 who were rifampicin-sensitive detected on CBNAAT, 68.1% (n=92) underwent FL-LPA, and out of the six rifampicin-resistant cases, 66.7% (n=4) underwent SL-LPA. Overall, 65.4% (142/217) completed the UDST algorithm. Children (aged <15 y) and people with bacteriological non-confirmation on microscopy were less likely to undergo rapid genotypic DST. Of 183 patients who underwent both rapid genotypic DST and sputum smear microscopy, 150 were bacteriologically confirmed and, of them, 9 (6%) were 'rapid DST-negative'.. We found gaps at various steps. There were a significant number of 'rapid DST-negative, smear-positive' patients.

Topics: Child; Cohort Studies; Humans; India; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant

Moxifloxacin is a recommended drug for rifampin-resistant tuberculosis (RR-TB) treatment, but there is limited pediatric pharmacokinetic and safety data, especially in young children. We characterize moxifloxacin population pharmacokinetics and QT interval prolongation and evaluate optimal dosing in children with RR-TB.. Pharmacokinetic data were pooled from 2 observational studies in South African children with RR-TB routinely treated with oral moxifloxacin once daily. The population pharmacokinetics and Fridericia-corrected QT (QTcF)-interval prolongation were characterized in NONMEM. Pharmacokinetic simulations were performed to predict expected exposure and optimal weight-banded dosing.. Eighty-five children contributed pharmacokinetic data (median [range] age of 4.6 [0.8-15] years); 16 (19%) were aged <2 years, and 8 (9%) were living with human immunodeficiency virus (HIV). The median (range) moxifloxacin dose on pharmacokinetic sampling days was 11 mg/kg (6.1 to 17). Apparent clearance was 6.95 L/h for a typical 16-kg child. Stunting and HIV increased apparent clearance. Crushed or suspended tablets had faster absorption. The median (range) maximum change in QTcF after moxifloxacin administration was 16.3 (-27.7 to 61.3) ms. No child had QTcF ≥500 ms. The concentration-QTcF relationship was nonlinear, with a maximum drug effect (Emax) of 8.80 ms (interindividual variability = 9.75 ms). Clofazimine use increased Emax by 3.3-fold. Model-based simulations of moxifloxacin pharmacokinetics predicted that current dosing recommendations are too low in children.. Moxifloxacin doses above 10-15 mg/kg are likely required in young children to match adult exposures but require further safety assessment, especially when coadministered with other QT-prolonging agents.

Topics: Adult; Child; Child, Preschool; Electrocardiography; Fluoroquinolones; HIV Infections; Humans; Moxifloxacin; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

To evaluate the 24-week interim outcomes of bedaquiline-containing regimens in the treatment of adolescents with rifampicin-resistant tuberculosis (RR-TB) in China.. Adolescents with RR-TB from two hospitals were included in this retrospective study. All patients received the longer regimen containing bedaquiline. Sputum culture, chest computed tomography, blood tests and electrocardiography were performed regularly, and the outcomes after 24 weeks of treatment were reported.. Four male and six female adolescents aged 11 to 17 years old were included. Among them, four (40.0%), four (40.0%) and two (20.0%) were confirmed to have RR-TB, multidrug-resistant TB and extensively drug-resistant TB, respectively. The most common companion drugs included linezolid (100.0%), cycloserine (90.0%), pyrazinamide (80.0%), moxifloxacin (50.0%) and levofloxacin (40.0%). Culture conversion rates of 80.0%, 100.0% and 100.0% were observed at weeks 2, 4 and 24, respectively. The mean maximum drug concentration of bedaquiline at weeks 2, 12 and 24 was 3.29 ± 0.66, 1.78 ± 0.81 and 1.93 ± 0.74 μg/mL, respectively. Six adverse events including leukopenia (50.0%), Fridericia-corrected QT (QTcF) interval prolongation (16.7%), anaemia (16.7%) and peripheral neuropathy (16.7%) were observed in five (50.0%) patients. No patient discontinued bedaquiline owing to QTcF interval prolongation. Meanwhile, no deaths, reversions or serious adverse events were reported during 24 weeks of treatment.. A longer regimen containing bedaquiline was effective and well tolerated in Chinese adolescents with RR-TB. The combination of bedaquiline and linezolid may be a favourable choice for this population.

Topics: Adolescent; Antitubercular Agents; Child; Diarylquinolines; Female; Humans; Male; Retrospective Studies; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant

N-(5-Chlorobenzo[d]oxazol-2-yl)-4-methyl-1,2,3-thiadiazole-5-carboxamideox-amide has been identified as a potent inhibitor of Mtb H37Rv, with a minimum inhibitory concentration (MIC) of 0.42 μM. In this study, a series of substituted 2-acylamide-1,3-zole analogues were designed and synthesized, and their anti-Mtb activities were analyzed. In total, 17 compounds were found to be potent anti-Mtb agents, especially against the MDR- and XDR-MTB strains, with MIC values < 10 μM. These analogues can inhibit both drug-sensitive and drug-resistant Mtb. Four representative compounds were selected for further profiling, and the results indicate that compound 18 is acceptably safe and has favorable pharmacokinetic (PK) properties. In addition, this compound displays potent activity against Gram-positive bacteria, with MIC values in the range of 1.48-11.86 μM. The data obtained herein suggest that promising anti-Mtb candidates may be developed via structural modification, and that further research is needed to explore other compounds.

Topics: Animals; Antitubercular Agents; Drug Design; Female; Halogenation; HEK293 Cells; Humans; Male; Mice; Mycobacterium tuberculosis; Oxazoles; Rats, Sprague-Dawley; Thiadiazoles; Tuberculosis, Multidrug-Resistant

Antimicrobial resistance is a main concern in tuberculosis treatment and is often associated with the emergence of Mycobacterium tuberculosis strains resistant to rifampicin (RIF), which is one of the cornerstones of tuberculosis chemotherapy. In this study, aminoalkyl-aromatic ring tails were appended to the C3 position of rifamycin core to assess the role of C3 substitutions to the anti-mycobacterial activity of the rifamycin antibiotics. The typical hydrazone unit of RIF was replaced by an amino-alkyl linkage to connect the aromatic ring tails with the rifamycin naphthoquinone core. Eight novel C3-(N-alkyl-aryl)-aminoalkyl analogues of rifamycin SV were synthesised and screened in vitro against wild-type HR37Rv and "hypervirulent" HN-878 strains, and a panel of rifampicin-resistant M. tuberculosis clinical isolates carrying mutations at the 522, 531 and 455 positions of the rpoB gene (RpoB

Topics: Antitubercular Agents; Binding Sites; Dose-Response Relationship, Drug; Microbial Sensitivity Tests; Molecular Structure; Mycobacterium tuberculosis; Rifamycins; Structure-Activity Relationship; Tuberculosis, Multidrug-Resistant

Determining factors affecting the transmission of rifampicin (RR) and multidrug-resistant (MDR) Mycobacterium tuberculosis complex strains under standardized tuberculosis (TB) treatment is key to control TB and prevent the evolution of drug resistance.. We combined bacterial whole genome sequencing (WGS) and epidemiological investigations for 37% (n = 195) of all RR/MDR-TB patients in Cameroon (2012-2015) to identify factors associated with recent transmission.. Patients infected with a strain resistant to high-dose isoniazid, and ethambutol had 7.4 (95% CI 2.6-21.4), and 2.4 (95% CI 1.2-4.8) times increased odds of being in a WGS-cluster, a surrogate for recent transmission. Furthermore, age between 30 and 50 was positively correlated with recent transmission (adjusted OR 3.8, 95% CI 1.3-11.4). We found high drug-resistance proportions against three drugs used in the short standardized MDR-TB regimen in Cameroon, i.e. high-dose isoniazid (77.4%), ethambutol (56.9%), and pyrazinamide (43.1%). Virtually all strains were susceptible to fluoroquinolones, kanamycin, and clofazimine, and treatment outcomes were mostly favourable (87.5%).. Pre-existing resistance to high-dose isoniazid, and ethambutol is associated with recent transmission of RR/MDR strains in our study. A possible contributing factor for this observation is the absence of universal drug susceptibility testing in Cameroon, likely resulting in prolonged exposure of new RR/MDR-TB patients to sub-optimal or failing first-line drug regimens.

Topics: Adult; Antitubercular Agents; Cameroon; Epidemiologic Studies; Genomics; Humans; Isoniazid; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Most Mycobacterium tuberculosis (Mtb) resistant to rifampicin (RIF) has mutations in the rpoB gene, while most Mtb resistant to isoniazid (INH) has mutations in the katG gene or inhA promoter. We used gene chip technology to detect mutations in these genes to determine the resistance of Mtb to RIF and INH. A total of 4148 clinical specimens with sputum smear positivity for acid-fast bacilli (AFB) were detected. Then, taking the results of the drug sensitivity test (DST) as the reference standard, the detection efficiency of sputum samples from different grades of positive smears was compared in detail. We found that the sensitivity of the gene chip method for detecting sputum samples with a grade ≥ AFB 2 + was higher than that of sputum samples with a grade ≤ AFB 1 + (P < 0.05). When the grade of the sample was ≤ AFB 1 +, the sensitivity of the gene chip method was 72.6% for RIF, 67.3% for INH, and 60.0% for MDR-TB. When the grade of the sample was ≥ AFB 2 +, the sensitivity of the gene chip method was 84.5% for RIF, 78.2% for INH, and 73.9% for MDR-TB. The results show that gene chip technology can be directly used to diagnose drug-resistant tuberculosis in clinical specimens, and the diagnostic efficiency for the detection of sputum specimens with a grade ≥ AFB 2 + is better than that of other sputum specimens.

Topics: Antibiotics, Antitubercular; Bacterial Proteins; Catalase; Codon; DNA-Directed RNA Polymerases; Drug Resistance, Multiple, Bacterial; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Oligonucleotide Array Sequence Analysis; Oxidoreductases; Retrospective Studies; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant

Emergence of drug resistant tuberculosis (DR-TB) has aggravated the tuberculosis (TB) public health burden worldwide and especially in low income settings. We present findings from a predominantly nomadic population in Karamoja, Uganda with a high-TB burden (3500 new cases annually) and sought to determine the prevalence, patterns, factors associated with DR-TB.. We used mixed methods of data collection. We enrolled 6890 participants who were treated for tuberculosis in a programmatic setting between January 2015 and April 2018. A cross sectional study and a matched case control study with conditional logistic regression and robust standard errors respectively were used to the determine prevalence and factors associated with DR-TB. The qualitative methods included focus group discussions, in-depth interviews and key informant interviews.. The overall prevalence of DR-TB was 41/6890 (0.6%) with 4/64,197 (0.1%) among the new and 37/2693 (1.4%) among the previously treated TB patients respectively. The drug resistance patterns observed in the region were mainly rifampicin mono resistant (68.3%) and Multi Drug-Resistant Tuberculosis (31.7%). Factors independently associated with DR-TB were previous TB treatment, adjusted odds ratio (aOR) 13.070 (95%CI 1.552-110.135) and drug stock-outs aOR 0.027 (95%CI 0.002-0.364). The nomadic lifestyle, substance use, congested homesteads and poor health worker attitudes were a great challenge to effective treatment of TB.. Despite having the highest national TB incidence, Karamoja still has a low DR-TB prevalence. Previous TB treatment and drug stock outs were associated with DR-TB. Regular supply of anti TB medications and health education may help to stem the burden of TB disease in this nomadic population.

Topics: Antitubercular Agents; Case-Control Studies; Cross-Sectional Studies; Humans; Mycobacterium tuberculosis; Prevalence; Rifampin; Tuberculosis, Multidrug-Resistant; Uganda

Zimbabwe is one of the 30 countries globally with a high burden of multidrug-resistant TB or rifampicin-resistant TB. The World Health Organization recommended that patients diagnosed with multidrug-resistant TB be treated with 20-24 month standardized second-line drugs since 2010. However, factors associated with mortality and treatment success have not been systematically evaluated in Zimbabwe. The Objective of the study was to assess factors associated with Mortality and treatment success among multidrug-resistant-TB patients registered and treated under the National Tuberculosis programme in Zimbabwe.. the study was conducted using secondary data routinely collected from the National tuberculosis (TB) programme. Categorical variables were summarised using frequencies and a generalized linear model with a log-link function and a Poisson distribution was used to assess factors associated with mortality and treatment success. The level of significance was set at P-Value < 0.05.. patient antiretroviral therapy (ART) status was a significant associated factor of treatment success or failure (RRR = 3.92, p < 0.001). Patients who were not on ART had a high risk of death by 3.92 times compared to patients who were on ART. In the age groups 45 - 54 years (relative risk ratios (RRR) = 1.41, p = 0.048), the risk of death was increased by 1.41 times compared to other age groups. Patients aged 55 years and above (RRR = 1.55, p = 0.017), had a risk of dying increased by 1.55 times compared to other age groups. Diagnosis time duration of 8 - 30 days (RRR = 0.62, p = 0.022) was found to be protective, a shorter diagnosis time duration between 8 to 30 days reduced the risk of TB deaths by 0.62 times compared to longer periods. Missed TB doses of > 10% (RRR = 2.03, p < 0.001) increased the risk of MDR/RR-TB deaths by 2.03 times compared to missing TB doses of ≤ 10%.. not being on ART when HIV positive was a major significant predictor of mortality. Improving ART uptake among those ART-naïve and strategies aimed at improving treatment adherence are important in improving treatment success rates.

Topics: Adolescent; Adult; Age Factors; Anti-HIV Agents; Antitubercular Agents; Child; Child, Preschool; Cohort Studies; Female; HIV Infections; Humans; Male; Middle Aged; Retrospective Studies; Rifampin; Risk Factors; Time Factors; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Young Adult; Zimbabwe

The morbidity of rifampicin/multidrug-resistant tuberculous meningitis (RR/MDR-TBM) has shown an increasing trend globally. Its mortality rate is significantly higher than that of non-rifampicin/multidrug-resistant tuberculous meningitis (NRR/MDR-TBM). This article aimed to explore risk factors related to RR/MDR-TBM, and compare therapeutic effects of linezolid (LZD)- and non-linezolid-containing regimen for RR/MDR-TB patients in Shenzhen city. Furthermore, we aimed to find a better therapy for pathogen-negative TBM with RR/MDR-TBM related risk factors.. We conducted a retrospective study enrolling 137 hospitalized cases with confirmed TBM from June 2014 to March 2020. All patients were divided into RR/MDR-TBM group (12 cases) and NRR/MDR-TBM group (125 cases) based on GeneXpert MTB/RIF and (or) phenotypic drug susceptibility test results using cerebral spinal fluid (CSF). The risk factors related to RR/MDR-TBM were investigated through comparing clinical and examination features between the two groups. The mortality rate of RR/MDR-TBM patients treated with different regimens was analyzed to compare their respective therapeutic effects. A difference of P < 0.05 was considered statistically significant.. Most patients (111/137, 81%) were from southern or southwestern China, and a large proportion (72/137, 52.55%) belonged to migrant workers. 12 cases were RR/MDR-TBM (12/137, 8.8%) while 125 cases were NRR/MDR-TBM (125/137, 91.2%). The proportion of patients having prior TB treatment history in the RR/MDR-TBM group was significantly higher than that of the NRR/MDR-TBM group (6/12 vs. 12/125, 50% vs. 10.5%, P < 0.01). No significant difference was observed on other clinical and examination features between the two groups. Mortality was significantly lower in RR/MDR-TBM patients on linezolid-containing treatment regimen than those who were not (0/7 versus 3/5, 0% versus 60%, P = 0.045).. The main related risk factor of RR/MDR-TBM is the history of anti-tuberculosis treatment. Linezolid-containing regimen appears to lower mortality rate of RR/MDR-TBM significantly in our study. We think Linezolid should be evaluated prospectively in the treatment of RR/MDR-TBM.

Topics: Antitubercular Agents; China; Humans; Linezolid; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Tuberculosis, Meningeal; Tuberculosis, Multidrug-Resistant

Topics: Adult; Child; Child, Preschool; Clinical Trials as Topic; Family Characteristics; Humans; Mass Screening; Mycobacterium tuberculosis; Research Design; Rifampin; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Fluoroquinolones; Genotype; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

There are few data on the on post-treatment experiences of people who have been successfully treated for rifampicin-resistant (RR-)TB.. To describe the experiences and impact of RR-TB disease and therapy on post-treatment life of individuals who were successfully treated.. In this qualitative study in-depth interviews were conducted among a purposively selected sample from a population of individuals who were successfully treated for RR-TB between January 2008 and December 2018. Interview transcripts and notes were analysed using a thematic network analysis which included grounded theory and a framework for understanding pathophysiological mechanisms for post-TB morbidity and mortality. The analysis was iterative and the coding system developed focused on disease, treatment and post-treatment experiences of individuals. This paper follows the COREQ guidelines.. For all 12 participants interviewed, the development of RR-TB disease, its diagnosis and the subsequent treatment were a major disruption to their lives as well as a transformative experience. On diagnosis of RR-TB disease, participants entered a liminal period in which their lives were marked with uncertainty and dominated by physical and mental suffering. Irrespective of how long ago they had completed their treatment, they all remembered with clarity the signs and symptoms of the disease and the arduous treatment journey. Post-treatment participants reported physical, social, psychological and economic changes as consequences of their RR-TB disease and treatment. Many participants reported a diminished ability to perform physical activities and, once discharged from the RR-TB hospital, inadequate physical rehabilitation. For some, these physical limitations impacted on their social life, and ultimately on their psychological health as well as on their ability to earn money and support their families.. The experiences and impact of RR-TB disease and therapy on post-treatment life of individuals successfully treated, highlights gaps in the current health care system that need to be addressed to improve the life of individuals post-treatment. A more holistic and long-term view of post-TB health, including the provision of comprehensive medical and social services for post-treatment care of physical ailments, social re-integration and the mitigation of the perceived fear and risk of getting TB again could be a central part of person-centred TB care.

Topics: Adult; Aged; Antitubercular Agents; Female; Humans; Male; Mental Health; Middle Aged; Qualitative Research; Rifampin; Tuberculosis, Multidrug-Resistant

Multidrug resistance is a major threat to global elimination of tuberculosis (TB). We performed phenotypic drug-susceptibility testing and whole-genome sequencing for 309 isolates from 342 consecutive patients who were given a diagnosis of TB in Yangon, Myanmar, during July 2016‒June 2018. We identified isolates by using the GeneXpert platform to evaluate drug-resistance profiles. A total of 191 (62%) of 309 isolates had rifampin resistance; 168 (88%) of these rifampin-resistant isolates were not genomically related, indicating the repeated emergence of resistance in the population, rather than extensive local transmission. We did not detect resistance mutations to new oral drugs, including bedaquiline and pretomanid. The current GeneXpert MTB/RIF system needs to be modified by using the newly launched Xpert MTB/XDR cartridge or line-probe assay. Introducing new oral drugs to replace those currently used in treatment regimens for multidrug-resistant TB will also be useful for treating TB in Myanmar.

Topics: Drug Resistance, Bacterial; Genomics; Humans; Microbial Sensitivity Tests; Myanmar; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Topics: Antibiotics, Antitubercular; Drug Resistance, Bacterial; Humans; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

The BD MAX MDR-TB is a recently marketed molecular test for detecting. This study aimed to evaluate the BD MAX MDR-TB test performance in 933 extrapulmonary and 774 pulmonary samples.. Test MTC detecting sensitivity was 90.6%, 82.5%, and the specificity was 98.5%, 98.9%, in pulmonary and extrapulmonary samples, respectively. In smear-positive samples, sensitivity, and specificity were 100% for all samples. However, in smear-negative samples, the test's sensitivity and specificity were 82.3%, 98.5% in pulmonary samples, and 76.7%, 98.9% in extrapulmonary samples. Test sensitivity in detecting isoniazid resistance was 71.4%, specificity 96.8%, and in detecting rifampin resistance was 100%, specificity 93.9%, respectively.. BD MAX MDR-TB is a reliable, rapid, user-friendly test for detecting MTC in extrapulmonary and pulmonary samples and its resistance toward isoniazid and rifampin. It can be used as an alternative to the Xpert system assays.

Topics: Antitubercular Agents; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

South Africa has a high burden of rifampicin-resistant tuberculosis (including multidrug-resistant [MDR] tuberculosis), with increasing rifampicin-monoresistant (RMR) tuberculosis over time. Resistance acquisition during first-line tuberculosis treatment could be a key contributor to this burden, and HIV might increase the risk of acquiring rifampicin resistance. We assessed whether HIV during previous treatment was associated with RMR tuberculosis and resistance acquisition among a retrospective cohort of patients with MDR or rifampicin-resistant tuberculosis.. In this retrospective cohort study, we included all patients routinely diagnosed with MDR or rifampicin-resistant tuberculosis in Khayelitsha, Cape Town, South Africa, between Jan 1, 2008, and Dec 31, 2017. Patient-level data were obtained from a prospective database, complemented by data on previous tuberculosis treatment and HIV from a provincial health data exchange. Stored MDR or rifampicin-resistant tuberculosis isolates from patients underwent whole-genome sequencing (WGS). WGS data were used to infer resistance acquisition versus transmission, by identifying genomically unique isolates (single nucleotide polymorphism threshold of five). Logistic regression analyses were used to assess factors associated with RMR tuberculosis and genomic uniqueness.. The cohort included 2041 patients diagnosed with MDR or rifampicin-resistant tuberculosis between Jan 1, 2008, and Dec 31, 2017; of those, 463 (22·7%) with RMR tuberculosis and 1354 (66·3%) with previous tuberculosis treatment. In previously treated patients, HIV positivity during previous tuberculosis treatment versus HIV negativity (adjusted odds ratio [OR] 2·07, 95% CI 1·35-3·18), and three or more previous tuberculosis treatment episodes versus one (1·96, 1·21-3·17) were associated with RMR tuberculosis. WGS data showing MDR or rifampicin-resistant tuberculosis were available for 1169 patients; 360 (30·8%) isolates were identified as unique. In previously treated patients, RMR tuberculosis versus MDR tuberculosis (adjusted OR 4·96, 3·40-7·23), HIV positivity during previous tuberculosis treatment (1·71, 1·03-2·84), and diagnosis in 2013-17 (1·42, 1·02-1·99) versus 2008-12, were associated with uniqueness. In previously treated patients with RMR tuberculosis, HIV positivity during previous treatment (adjusted OR 5·13, 1·61-16·32) was associated with uniqueness as was female sex (2·50 [1·18-5·26]).. These data suggest that HIV contributes to rifampicin-resistance acquisition during first-line tuberculosis treatment and that this might be driving increasing RMR tuberculosis over time. Large-scale prospective cohort studies are required to further quantify this risk.. Swiss National Science Foundation, South African National Research Foundation, and Wellcome Trust.

Topics: Drug Resistance; Female; HIV Infections; Humans; Molecular Epidemiology; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; South Africa; Tuberculosis; Tuberculosis, Multidrug-Resistant

Clinical isolates with discordant phenotypic and genotypic results were submitted to DNA sequencing to identify which were genuinely resistant to rifampin and determine the frequency of silent and disputed mutations in our region. We present the retrospective analysis of all the culture-proven TB cases tested with the Xpert®MTB/RIF assay at the Tuberculosis Clinic and Laboratory of the Tijuana General Hospital, Mexico. Clinical isolates showing a discrepancy between phenotypic and molecular tests were analyzed by DNA sequencing. Thirteen isolates tested as rifampin susceptible on the MGIT system were rifampin-resistant according to Xpert®MTB/RIF assay. DNA sequencing showed that seven (53.8%) isolates had a silent (P514P) mutation; three isolates showed different missense (L511P, D516Y, and S531L) mutations. Three isolates showed no mutations. The existence of heteroresistance and silent or disputed mutations warrants that all rifampin-resistance cases diagnosed with the Xpert®MTB/RIF should be referred to specialized centers for DNA sequencing.

Topics: Antibiotics, Antitubercular; Diagnostic Tests, Routine; Drug Resistance, Bacterial; Genotype; Mycobacterium tuberculosis; Phenotype; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant

Topics: Antibiotics, Antitubercular; COVID-19; Humans; Mycobacterium tuberculosis; Rifampin; SARS-CoV-2; Tuberculosis, Multidrug-Resistant

Multidrug-resistant tuberculosis (MDR-TB) drugs have never been associated with erythrocytosis. In Eritrea, however, several cases of incident erythrocytosis had been observed in the MDR-TB hospital. This study was aimed at exploring the association between MDR-TB drugs and secondary erythrocytosis, characterising the cases, and identifying other possible risk factors.. A total of 257 patients' medical cards were screened, and 219 were eligible for further analysis. The median age of the patients was 38 years (range: 13-90 years) and 54.8% were males. During the follow-up time, 31 (14.2%) patients developed secondary erythrocytosis yielding an incidence rate of 7.8 cases per 1000 person-months. On average, the median time to onset of the event was found to be 5-months (range: 1-24 months). Males were more likely to develop the event than females (adjusted HR=7.13, 95% CI=1.66 to 30.53), and as body weight increases by 1 kg, the likelihood of developing secondary erythrocytosis was found to increase by 7% (adjusted HR=1.07, 95% CI=1.03 to 1.10). Moreover, all cases of secondary erythrocytosis were found to be possibly associated with the MDR-TB drugs.. The authors hypothesised that the incident erythrocytosis is possibly be associated with MDR-TB drugs, and further studies are required to substantiate this finding.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antitubercular Agents; Female; Humans; Male; Middle Aged; Pharmaceutical Preparations; Polycythemia; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant; Young Adult

Phenotypic drug susceptibility testing (DST) for tuberculosis (TB) requires weeks to yield results. Although molecular tests rapidly detect drug resistance-associated mutations (DRMs), they are not scalable to cover the full genome and the many DRMs that can predict resistance. Whole-genome sequencing (WGS) methods are scalable, but if conducted directly on sputum, typically require a target enrichment step, such as nucleic acid amplification. We developed a targeted isothermal amplification-nanopore sequencing workflow for rapid prediction of drug resistance of TB isolates. We used recombinase polymerase amplification (RPA) to perform targeted isothermal amplification (37°C for 90 min) of three regions within the Mycobacterium tuberculosis genome, followed by nanopore sequencing on the MinION. We tested 29 mycobacterial genomic DNA extracts from patients with drug-resistant (DR) TB and compared our results to those of WGS by Illumina and phenotypic DST to evaluate the accuracy of prediction of resistance to rifampin and isoniazid. Amplification by RPA showed fidelity equivalent to that of high-fidelity PCR (100% concordance). Nanopore sequencing generated DRM predictions identical to those of WGS, with considerably faster sequencing run times of minutes rather than days. The sensitivity and specificity of rifampin resistance prediction for our workflow were 96.3% (95% confidence interval [CI], 81.0 to 99.9%) and 100.0% (95% CI, 15.8 to 100.0%), respectively. For isoniazid resistance prediction, the sensitivity and specificity were 100.0% (95% CI, 86.3 to 100.0%) and 100.0% (95% CI, 39.8 to 100.0%), respectively. The workflow consumable costs per sample are less than £100. Our rapid and low-cost drug resistance genotyping workflow provides accurate prediction of rifampin and isoniazid resistance, making it appropriate for use in resource-limited settings.

Topics: Antitubercular Agents; Drug Resistance, Bacterial; Genotype; Humans; Isoniazid; Mycobacterium tuberculosis; Nanopore Sequencing; Polymerase Chain Reaction; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant; Workflow

Multiple drug resistance TB (MDR-TB) has greatly jeopardized the effective control of tuberculosis in Africa. This study is aimed at determining the incidence and predictors of drug resistant-TB amongst bacteriologically diagnosed cases in the Littoral region of Cameroon. This was a descriptive cross-sectional survey conducted from January 2016 to December 2017. A total of 1665 participants were enrolled from 32 diagnostic and treatment centers (DTCs) in the Littoral region. Demographic, clinical, socioeconomic, and behavioral data were obtained using a pretested structured questionnaire. Drug susceptibility testing was performed using Gene Xpert MTB/RIF assay and line probe assay (LPA). Consent was obtained from participant/guidance. Data analysis was carried with SPSS version 21. Univariate and multiple logistic regression was performed at 5% significance level. The incidence of rifampicin and MDR-TB was 86 (5.2%) and 75 (4.5%), respectively. More (11.3%) cases of drug resistance were diagnosed in 2016 compared to 2017 (3.7%). Eleven (0.7%) were resistant to rifampicin only. A total of 19 (4.4%) cases of rifampicin resistance were detected from newly diagnosed cases and 67 (5.4%) from previously retreated cases. Pre-XDR-TB was detected in 2 (2.7%) of the MDR-TB cases amongst whom 1 (1.3%) was extensive drug resistance TB (XDR-TB). Age greater than 60 years old (OR = 4.98,

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antitubercular Agents; Cameroon; Child; Child, Preschool; Cross-Sectional Studies; Drug Resistance, Bacterial; Female; Humans; Incidence; Infant; Logistic Models; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Prevalence; Rifampin; Risk Factors; Tuberculosis, Multidrug-Resistant; Young Adult

There was a complete lack of information about the treatment outcomes of rifampicin/multidrug resistant (RR/MDR) childhood TB patients (age ≤ 14 years) from Pakistan, an MDR-TB 5th high burden country. Therefore, this study evaluated the socio-demographic characteristics, drug resistance pattern, treatment outcomes and factors associated with unsuccessful outcomes among childhood RR/MDR-TB patients in Pakistan.. This was a multicentre retrospective record review of all microbiologically confirmed childhood RR/MDR-TB patients (age ≤ 14 years) enrolled for treatment at seven units of programmatic management of drug-resistant TB (PMDT) in Pakistan. The baseline and follow-up information of enrolled participants from treatment initiation until the end of treatment were retrieved from electronic nominal recording and reporting system. World Health Organization (WHO) defined criterion was used for deciding treatment outcomes. The outcomes of "cured" and "treatment completed" were collectively grouped as successful, whereas "death", "treatment failure" and "lost to follow-up" were grouped together as unsuccessful outcomes. Multivariable binary logistic regression analysis was used to find factors associated with unsuccessful outcomes. A p-value < 0.05 reflected statistically significant findings.. A total of 213 children RR/MDR-TB (84 RR and 129 MDR-TB) were included in the study. Majority of them were females (74%), belonged to the age group 10-14 years (82.2%) and suffered from pulmonary TB (85.9%). A notable proportion (37.1%) of patients had no history of previous TB treatment. Patients were resistant to a median of two drugs (interquartile range: 1-4) and 23% were resistant to any second line anti-TB drug. A total of 174 (81.7%) patients achieved successful treatment outcomes with 144 (67.6%) patients being cured and 30 (14.1%) declared treatment completed. Among the 39 (18.3%) patients with unsuccessful outcomes, 35 (16.4%) died and 4 (1.9%) experienced treatment failure. In multivariable analysis, the use of ethambutol had statistically significant negative association with unsuccessful outcomes (odds ratio = 0.36, p-value = 0.02).. In this study, the WHO target of successful treatment outcomes (≥ 75%) among childhood RR/MDR-TB patients was achieved. The notable proportion of patients with no history of previous TB treatment (37.1%) and the disproportionately high number of female patients (74%) respectively stress for infection control measures and provision of early and high quality care for female drug susceptible TB patients.

Topics: Adolescent; Antitubercular Agents; Child; Female; Humans; Pakistan; Retrospective Studies; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant

To evaluate China's current rifampin-resistant tuberculosis (RR-TB) screening strategy from stakeholders' perspectives, the perceptions, attitudes, and interests of 245 stakeholders from three eastern, central, and western China provinces on RR-TB screening strategies, were investigated through stakeholder survey and interview. The attitudes toward three RR-TB screening strategies were statistically different: inclination to choose who to screen (

Topics: Humans; Mass Screening; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Short-course, rifamycin-based regimens could facilitate scale-up of tuberculosis preventive therapy (TPT), but it is unclear how stringently tuberculosis (TB) disease should be ruled out before TPT use.. We developed a state-transition model of a TPT intervention among two TPT-eligible cohorts: adults newly diagnosed with HIV in South Africa (PWH) and TB household contacts in Pakistan (HHCs). We modeled two TPT regimens-4 months of rifampicin [4R] or 6 months of isoniazid [6H]-comparing each to a reference of no intervention. Before initiating TPT, TB disease was excluded either through symptom-only screening or with additional radiographic screening that could detect subclinical TB but might limit access to the TPT intervention. TPT's potential curative effects on both latent and subclinical TB were modeled, as were both acquisitions of resistance and prevention of drug-resistant disease. Although all eligible individuals received the screening and/or TPT interventions, the modeled TB outcomes comprised only those with latent or subclinical TB that would have progressed to symptomatic disease if untreated.. When prescribed after only symptom-based TB screening (such that individuals with subclinical TB were included among TPT recipients), 4R averted 45 active (i.e., symptomatic) TB cases (95% uncertainty range 24-79 cases or 40-89% of progressions to active TB) per 1000 PWH [17 (9-29, 43-94%) per 1000 HHCs]; 6H averted 37 (19-66, 52-73%) active TB cases among PWH [13 (7-23, 53-75%) among HHCs]. With this symptom-only screening, for each net rifampicin resistance case added by 4R, 12 (3-102) active TB cases were averted among PWH (37 [9-580] among HHCs); isoniazid-resistant TB was also reduced. Similarly, 6H after symptom-only screening increased isoniazid resistance while reducing overall and rifampicin-resistant active TB. Screening for subclinical TB before TPT eliminated this net increase in resistance to the TPT drug; however, if the screening requirement reduced TPT access by more than 10% (the estimated threshold for 4R among HHCs) to 30% (for 6H among PWH), it was likely to reduce the intervention's overall TB prevention impact.. All modeled TPT strategies prevent TB relative to no intervention, and differences between TPT regimens or between screening approaches are small relative to uncertainty in the outcomes of any given strategy. If most TPT-eligible individuals can be screened for subclinical TB, then pairing such screening with rifamycin-based TPT maximizes active TB prevention and does not increase rifampicin resistance. Where subclinical TB cannot be routinely excluded without substantially reducing TPT access, the choice of TPT regimen requires weighing 4R's efficacy advantages (as well as its greater safety and shorter duration that we did not directly model) against the consequences of rifampicin resistance in a small fraction of recipients.

Topics: Adult; Antitubercular Agents; Humans; Isoniazid; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

A laboratory validation study was conducted to assess the equivalence of Xpert MTB/RIF Ultra testing on the GeneXpert System and the GeneXpert Omni System ('Omni') for tuberculosis and rifampicin resistance. High concordance of the two devices was demonstrated for well-characterized clinical samples as well as control materials, with controls tested on Omni at normal and challenging environmental conditions (i.e. 35°C, 90% relative humidity). Equivalence of the Cts for all probes was also shown. Equivalence was demonstrated for the Omni and GeneXpert devices for tuberculosis and rifampicin resistance detection for a diverse range of clinical specimens and environmental conditions.

Topics: Antibiotics, Antitubercular; Bacterial Proteins; DNA-Directed RNA Polymerases; Drug Resistance, Multiple, Bacterial; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Point-of-Care Testing; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

There is paucity of data on the prevalence and distribution of multidrug- Resistant-Tuberculosis (MDR-TB) in the Republic of Congo. Among the challenges resides the implementation of a robust TB resistance diagnostic program using molecular tools. In resource limited settings there is a need to gather data to enable prioritization of actions. The objective of this study was is to implement molecular tools as a best of diagnosing MDR and XDR-TB among presumptive tuberculosis patients referred to reference hospital of Makelekele in Brazzaville, Republic of the Congo.. We have conducted a cross-sectional study, including a total of 92 presumptive pulmonary tuberculosis patients and who had never received treatment recruited at the reference hospital of Makelekele from October 2018 to October 2019. The socio-demographic and clinical data were collected as well as sputum samples. Rifampicin resistance was investigated using Xpert (Cepheid) and second-line TB drugs Susceptibility testing were performed by the Brucker HAIN Line Probe Assay (GenoType MTBDRsl VER 2.0 assay) method.. From the 92 recruited patients, 57 (62%) were found positive for the Mycobacterium tuberculosis complex. The prevalence of rifampicin-resistant tuberculosis (RR-TB) was 9.8% (9/92) and importantly 2.2% were pre-XDR/XDR.. This study showed a high rate of rifampicin resistance and the presence of extensively drug-resistant tuberculosis in the study area in new patients. This study highlights the need for further studies of TB drug resistance in the country.

Topics: Adolescent; Adult; Antitubercular Agents; Congo; Cross-Sectional Studies; Extensively Drug-Resistant Tuberculosis; Female; Humans; Male; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Young Adult

Rapid and sensitive Tuberculosis (TB) diagnosis closer to patients is a key global TB control priority. Truenat assays (MTB, MTB Plus, and MTB-RIF Dx) are new TB molecular diagnostic tools for the detection of TB and Rifampicin (RIF)-resistance from sputum samples. The diagnostic accuracy of the assays is needed prior to implementation in clinical use in Ethiopia. This study aimed to determine the sensitivity and specificity of Truenat assays; and aimed to compare the assays to the Xpert MTB/RIF assay.. A prospective evaluation study was conducted among 200 presumptive TB patients in microscopy centers in Addis Ababa, Ethiopia from May 2019 to December 2020. Culture (Solid and Liquid methods) and phenotypic (liquid method) drug susceptibility testing (DST) were used as a reference standard.. Of 200 adult participants, culture confirmed TB cases were 25 (12.5%), and only one isolate was resistant to RIF by phenotypic DST. The sensitivity of Truenat MTB was 88.0% [95% CI 70.1, 95.8], while 91.7 [95% CI 74.2, 97.7] for Truenat MTB Plus at the microscopy centers. The specificity of Truenat MTB was 97.2% [95% CI 93.1, 98.9], while for Truenat MTB Plus was 97.2% [95% CI 93.0, 99.0]. The sensitivity of Truenat MTB was 90.5% while for MTB Plus, 100% compared to the Xpert MTB/RIF assay.. Truenat assays were found to have high diagnostic accuracy. The assays have the potential to be used as a point of care (POC) TB diagnostic tests.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Biological Assay; Diagnostic Tests, Routine; Ethiopia; Female; Humans; Male; Middle Aged; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Young Adult

Topics: Diarylquinolines; Female; Humans; Infant; Pregnancy; Pregnant Women; Rifampin; South Africa; Tuberculosis, Multidrug-Resistant

Rifampicin (RIF) resistance is highly correlated with isoniazid (INH) resistance and used as proxy for multidrug-resistant tuberculosis (MDR-TB). Using MTBDRplus as a comparator, we evaluated the predictive value of Xpert MTB/RIF (Xpert)-detected RIF resistance for MDR-TB in eastern Democratic Republic of the Congo (DRC).. We conducted a cross-sectional study involving data from new or retreatment pulmonary adult TB cases evaluated between July 2013 and December 2016. Separate, paired sputa for smear microscopy and MTBDRplus were collected. Xpert testing was performed subject to the availability of Xpert cartridges on sample remnants after microscopy.. Among 353 patients, 193 (54.7%) were previously treated and 224 (63.5%) were MTBDRplus TB positive. Of the 224, 43 (19.2%) were RIF monoresistant, 11 (4.9%) were INH monoresistant, 53 (23.7%) had MDR-TB, and 117 (52.2%) were RIF and INH susceptible. Overall, among the 96 samples detected by MTBDRplus as RIF resistant, 53 (55.2%) had MDR-TB. Xpert testing was performed in 179 (50.7%) specimens; among these, 163 (91.1%) were TB positive and 73 (44.8%) RIF resistant. Only 45/73 (61.6%) Xpert-identified RIF-resistant isolates had concomitant MTBDRplus-detected INH resistance. Xpert had a sensitivity of 100.0% (95% CI, 92.1-100.0) for detecting RIF resistance but a positive-predictive value of only 61.6% (95% CI, 49.5-72.8) for MDR-TB. The most frequent mutations associated with RIF and INH resistance were S531L and S315T1, respectively.. In this high-risk MDR-TB study population, Xpert had low positive-predictive value for the presence of MDR-TB. Comprehensive resistance testing for both INH and RIF should be performed in this setting.

Topics: Adult; Cross-Sectional Studies; Democratic Republic of the Congo; Humans; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

The short treatment regimen (STR) achieves a >80% cure in rifampicin-resistant tuberculosis (RR-TB) patients. However, ototoxicity induced by the injectable is a concern. This is the first study to evaluate the replacement of injectables by linezolid in patients with audiometry abnormalities at baseline or during the treatment.We conducted a retrospective cohort study of all RR-TB patients started on the STR between 2016 and June, 2019, in Niger. Patients underwent audiometry every 2 months in 2016 and every month since 2017.Of 195 patients, 16.9% (33 out of 195) received linezolid from the start (n=17), or switched from injectables to linezolid during treatment (n=16), based on audiometry abnormalities. In 2016, two patients developed severe ototoxicity despite switching to linezolid. Since 2017, no patient developed severe hearing loss or complete deafness. Severe haematological toxicity was observed in 18.1% (six out of 33) of patients on linezolid, none of which was life threatening. The use of linezolid was associated with severe but manageable adverse events (hazard ratio 8.9, 95% CI 2.5-31.5; p=0.001). A total of 90.9% (30 out of 33) of patients on a linezolid-containing STR were cured, and none experienced treatment failure. Three died, but not due to adverse events.Baseline and monthly audiometry monitoring and using linezolid after detection of hearing abnormalities appears effective to prevent severe ototoxicity, while keeping high treatment success and manageable adverse events.

Topics: Antitubercular Agents; Deafness; Hearing Loss; Humans; Linezolid; Ototoxicity; Retrospective Studies; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant

Previous analyses suggest that children with tuberculosis (TB) are no more or no less likely to have multidrug (MDR)- or rifampicin-resistant (RR)-TB than adults. However, the availability of new data, particularly for high MDR/RR-TB burden countries, suggest updates of country-specific estimates are warranted.We used data from population-representative surveys and surveillance collected between 2000 and 2018 to compare the odds ratio of MDR/RR-TB among children (aged <15 years) with TB, compared to the odds of MDR/RR-TB among adults (aged ≥15 years) with TB.In most settings (45 out of 55 countries), and globally as a whole, there is no evidence that age is associated with odds of MDR/RR-TB. However, in some settings, such as former Soviet Union countries in general, and Georgia, Kazakhstan, Lithuania, Tajikistan and Uzbekistan in particular, as well as Peru, MDR/RR-TB is positively associated with age ≥15 years. Meanwhile, in Western Europe in general, and the United Kingdom, Poland, Finland and Luxembourg in particular, MDR/RR-TB is positively associated with age <15 years. 16 countries had sufficient data to compare over time between 2000-2011 and 2012-2018, with evidence for decreases in the odds ratio in children compared to adults in Germany, Kazakhstan and the United States of America.Our results support findings that in most settings a child with TB is as likely as an adult with TB to have MDR/RR-TB. However, setting-specific heterogeneity requires further investigation. Furthermore, the odds ratio for MDR/RR-TB in children compared to adults is generally either stable or decreasing. There are important gaps in detection, recording and reporting of drug resistance among paediatric TB cases, limiting our understanding of transmission risks and measures needed to combat the global TB epidemic.

Topics: Adolescent; Adult; Antitubercular Agents; Child; Europe; Finland; Germany; Humans; Mycobacterium tuberculosis; Peru; Poland; Rifampin; Tuberculosis, Multidrug-Resistant; United Kingdom

To assess the prevalence and risk factors of drug-resistant tuberculosis (TB), the fifth national anti-TB drug resistance survey was conducted in Thailand.. A cross-sectional study was conducted by stratified cluster sampling with probability proportional to size of TB cases from public health facilities in 100 clusters throughout Thailand from August 2017 to August 2018. Susceptibility testing of TB isolates to first- and second-line anti-TB drugs was performed on Löwenstein-Jensen medium using the indirect proportion method. Multiple imputation was done for handling missing data using Stata 16. The proportion of TB cases with drug resistance was determined. The odds ratio was used to evaluate risk factors associated with drug-resistant TB.. Among 1501 new TB and 69 previously treated TB cases, 14.0% [95% confidence interval (CI): 12.1-16.1] and 33.4% (95% CI: 23.6-44.8), respectively, had resistance to any anti-TB drug. Multidrug-resistant TB accounted for 0.8% (95% CI: 0.5-1.4) of new TB cases and 13.0% (95% CI: 6.5-24.4) of previously treated TB cases. Drug-resistant TB was associated with prior TB treatment [odds ratio (OR), 2.9; 95% CI: 1.6-5.0], age at 45-54 years (OR, 1.6; 95% CI: 1.0-2.4), male (OR, 1.5; 95% CI: 1.0-2.1) and human immunodeficiency virus (HIV) infection (OR, 1.6; 95% CI: 1.0-2.4).. The burden of drug-resistant TB remains high in Thailand. Intensified prevention and control measures should be implemented to reduce the risks of drug-resistant TB in high-risk groups previously treated, especially individuals of late middle age, males and those with coinfection of TB and HIV.

Topics: Adolescent; Adult; Aged; Antitubercular Agents; Coinfection; Cross-Sectional Studies; Drug Resistance, Bacterial; Female; HIV Infections; Humans; Logistic Models; Male; Microbial Sensitivity Tests; Middle Aged; Multivariate Analysis; Mycobacterium tuberculosis; Prevalence; Rifampin; Risk Factors; Sputum; Thailand; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

The resistance to first-line drugs can increase the risk of treatment failure and development of resistance to other anti-TB drugs. In TB endemic settings, a considerable rate of recurrence cases exhibited each, year which adds significant burden to the prevalence of disease worldwide.. A total of 562 sputum samples were collected from presumptive positive clinical cases of MDR tuberculosis. Treatment history and demographic data of the patients were obtained after informed consent. Xpert MTB/RIF assay was performed for simultaneous detection of MTB and rifampicin resistance. The mutation patterns of isoniazid and rifampicin were observed after multiplex PCR and reverse hybridization by Genotype® MTBDRplus version 2.0 assay.. A total of 73 of 97 cases (75.2%) of treatment failure were found positive for MDR-TB, whereas 79.6% newly diagnosed and 72.9% default cases were MDR in our isolates. The mutation of rpoB S531L was slightly higher in new treatment cases (89.3%) as compared to the default (80.4%) and failure cases (84.8%), whereas rpoB D516V mutation was more prevalent in default cases (19.6%) with complete absence of rpoB 526 mutation, which was observed in the other two types of cases. The mutation pattern of katG resistance differed among drug naïve and recurrence cases. The resistance in newly diagnosed cases was mostly conferred by katG 315 (49.1%) whereas in default (70.8%) and failure cases (63.3%) isoniazid resistance was commonly associated with katG S315T1 mutation. Mutations in inhA promoter region occurred at nucleotide position -8 and -15. In new cases the rate of mutation of C-15T was 3.7% and T-8A was 1.5% while in treatment failure cases the frequency for C-15T and T-8C was 2.5 and 3.8% respectively. However, no inhA promoter region mediated mutations were detected in default treatment cases.. Retreated cases are at more risk of developing hot spot mutations. An unusual difference in mutation pattern was determined in naïve and recurrence cases. Some mutations were exclusively associated with the retreatment of 35anti-TB drugs which suggest the increased risk of resistance with poor treatment outcome.

Topics: Adult; Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Female; Humans; Isoniazid; Male; Middle Aged; Mutation; Mycobacterium tuberculosis; Reinfection; Rifampin; Treatment Failure; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

In its 2020 guidelines for the treatment of rifampicin-resistant TB (RR-TB), the WHO recommends all-oral fluoroquinolone-based regimens, with bedaquiline replacing the second-line injectable drugs (SLIDs). SLIDs were used for their strong acquired resistance-preventing activity. Data from three cohorts showed acquired bedaquiline resistance ranging between 2.5% and 30.8%, with no protection from a SLID in most cases. If bedaquiline resistance is that easily acquired, it will fail to protect fluoroquinolones and other drugs from acquiring resistance. Until evidence on resistance-preventing activity shows that SLIDs can safely be replaced, we call for more prudent use of the few potent second-line TB drugs available. Studies on new treatment regimens need to prioritize the prevention of acquired resistance along with treatment success. Meanwhile, reducing the dosing of SLIDs to thrice weekly from Day 1, and their replacement for any degree of audiometry abnormalities before or during treatment will largely avoid serious ototoxicity.

Topics: Antitubercular Agents; Fluoroquinolones; Humans; Pharmaceutical Preparations; Rifampin; Tuberculosis, Multidrug-Resistant

Linezolid presents strong antimicrobial activity against multidrug-resistant (MDR) pulmonary tuberculosis (TB), but its application in osteoarticular tuberculosis treatment remains understudied. Our objective was to analyze the bone penetration efficiency of linezolid in osteoarticular TB patients.. Osteoarticular TB patients, treated with 600 mg q 24 h linezolid-containing regimens and undergoing surgery, were prospectively and consecutively enrolled. One dose linezolid was administered before surgery. Blood and bone samples were collected simultaneously during operation, and their linezolid concentrations were then detected using high-performance liquid chromatography-tandem mass spectrometry. Pus samples were subjected to mycobacterial culture and GeneXpert MTB/RIF assay. The minimum inhibition concentrations (MICs) and drug susceptibility testing were performed with the recovered isolates.. A total of 36 eligible osteoarticular TB patients were enrolled, including five MDR/rifampicin-resistant cases. All the 12 recovered isolates had MICs ≤0.5 μg/mL for linezolid. Mean concentrations in plasma, collected 100-510 min after the preoperative dosing, were 10.43 ± 4.83 μg/mL (range 3.29-22.26 μg/mL), and median concentrations in bone were 3.93 μg/mL (range 0.61-16.34 μg/mL). The median bone/plasma penetration ratio was 0.42 (range 0.14-0.95 μg/mL). Linezolid concentration in bone had a linear correlation with the drug concentration in plasma (r = 0.7873, p < 0.0001), while plasma concentration could explain 61.98% of the variation of concentration in bone (R. Linezolid penetrates from blood to bone efficiently, and the penetration further stabilizes ∼3 h after dosing.

Topics: Anti-Bacterial Agents; Antitubercular Agents; China; Chromatography, High Pressure Liquid; Female; Humans; Linezolid; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Rifampin; Tissue Distribution; Tuberculosis, Multidrug-Resistant; Tuberculosis, Osteoarticular; Young Adult

At the end of 2018, South Africa updated its all-oral regimen, to include bedaquiline (BDQ) and 2 months of linezolid (LZD) for all patients initiating the shorter 9-12 months regimen for rifampicin-resistant tuberculosis (RR-TB). We assessed a group of patients in rural KwaZulu-Natal for safety and effectiveness of this treatment regimen under programmatic conditions.. We conducted a retrospective cohort analysis on RR-TB patients treated with a standardized all-oral short regimen between 1 July 2018 and 30 April 2019 in 3 facilities in King Cetshwayo District. An electronic register (EDR web) and facility-based clinical charts were used to collect variables, which were entered into an Epi-Info database.. Our cohort included 117 patients; 68.4% (95% confidence interval [CI]: 59.3-76.3) tested positive for human immunodeficiency virus (HIV). The median time to culture conversion was 56 days (95% CI: 50-57). Treatment success was achieved in 75.2% (95% CI: 66.5-82.3) of patients. Mortality within the cohort was 12.8% (95% CI: 7.8-20.3). Anemia was the most frequent severe adverse event (AE). The median time to develop severe anemia was 7.1 weeks (interquartile range [IQR] 4.0-12.9) after treatment initiation. LZD was interrupted in 25.2% (95% CI: 17.8-34.5) of participants.. An all-oral shorter regimen, including BDQ and LZD as core drugs for the treatment of RR-TB, shows good outcomes, in a high HIV burden rural setting. AEs are common, especially for LZD, but could be managed in the program setting. Support is needed when introducing new regimens to train staff in the monitoring, management, and reporting of AEs.

Topics: Antitubercular Agents; Cohort Studies; Diarylquinolines; HIV; HIV Infections; Humans; Retrospective Studies; Rifampin; South Africa; Tuberculosis, Multidrug-Resistant

As per national policy, all diagnosed tuberculosis patients in India are to be tested using Xpert® MTB/RIF assay at the district level to diagnose rifampicin resistance. Regardless of the result, samples are transported to the reference laboratories for further testing: first-line Line Probe Assay (FL-LPA) for rifampicin-sensitive samples and second-line LPA(SL-LPA) for rifampicin-resistant samples. Based on the results, samples undergo culture and phenotypic drug susceptibility testing. We assessed among patients diagnosed with tuberculosis at 13 selected Xpert laboratories of Karnataka state, India, i) the proportion whose samples reached the reference laboratories and among them, proportion who completed the diagnostic algorithm ii) factors associated with non-reaching and non-completion and iii) the delays involved.. This was a cohort study involving review of programme records. For each TB patient diagnosed between 1st July and 31st August 2018 at the Xpert laboratory, we tracked the laboratory register at the linked reference laboratory until 30th September (censor date) using Nikshay ID (a unique patient identifier), phone number, name, age and sex.. Of 1660 TB patients, 1208(73%) samples reached the reference laboratories and among those reached, 1124(93%) completed the algorithm. Of 1590 rifampicin-sensitive samples, 1170(74%) reached and 1104(94%) completed the algorithm. Of 64 rifampicin-resistant samples, only 35(55%) reached and 17(49%) completed the algorithm. Samples from rifampicin-resistant TB, extra-pulmonary TB and two districts were less likely to reach the reference laboratory. Non-completion was more likely among rifampicin-resistant TB and sputum-negative samples. The median time for conducting and reporting results of Xpert® MTB/RIF was one day, of FL-LPA 5 days and of SL-LPA16 days.. These findings are encouraging given the complexity of the algorithm. High non-reaching and non-completion rates in rifampicin-resistant patients is a major concern. Future research should focus on understanding the reasons for the gaps identified using qualitative research methods.

Topics: Adolescent; Adult; Algorithms; Child; Cohort Studies; Drug Resistance, Bacterial; Female; Humans; India; Male; Middle Aged; Mycobacterium tuberculosis; Reagent Kits, Diagnostic; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Young Adult

In this retrospective study, we evaluated the diagnostic accuracy of molecular tests (MT) for the detection of DR-TB, compared to the gold standard liquid-based drug susceptibility testing (DST) in Karakalpakstan.. A total of 6670 specimens received in the Republican TB No 1 Hospital Laboratory of Karakalpakstan between January and July 2017 from new and retreatment patients were analysed. Samples were tested using Xpert MTB/RIF and line probe assays (LPA) for the detection of mutations associated with resistance. The sensitivity and specificity of MTs were calculated relative to results based on DST.. The accuracy of MT for detection of rifampicin resistance was high, with sensitivity and specificity over 98%. However, we observed reduced sensitivity of LPA for detection of resistance; 86% for isoniazid (95% CI 82-90%), 86% for fluoroquinolones (95% CI 68-96%), 70% for capreomycin (95% CI 46-88%) and 23% for kanamycin (95% CI 13-35%).. We show that MTs are a useful tool for rapid and safe diagnosis of DR-TB; however, clinicians should be aware of their limitations. Although detection of rifampicin resistance was highly accurate, our data suggest that resistance mutations circulating in the Republic of Karakalpakstan for other drugs were not detected by the methods used here. This merits further investigation.

Topics: Antibiotics, Antitubercular; Capreomycin; Drug Resistance, Bacterial; Fluoroquinolones; Humans; Isoniazid; Kanamycin; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Polymerase Chain Reaction; Reproducibility of Results; Retrospective Studies; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Uzbekistan

Treatment for rifampicin-resistant Mycobacterium tuberculosis (RR-TB) is complex, however, shorter treatment, with newer antimicrobials are improving treatment outcomes. The South African National Department of Health (NDoH) recently accelerated the rollout of 9-month, all-oral, RR-TB short-course regimens. We sought to evaluate an inter-professional training program using pre-test and post-test performance of Professional Nurses (PNs), Advanced Practice Professional Nurses (APPNs) and Medical Officers (MOs) to inform: (a) training needs across cadres; (b) knowledge performance, by cadres; and (c) training differences in knowledge by nurse type.. A 4-day didactic and case-based clinical decision support course for RR-TB regimens in South Africa (SA) was developed, reviewed and nationally accredited. Between February 2017 and July 2018, 12 training events were held. Clinicians who may initiate RR-TB treatment, specifically MOs and PN/APPNs with matched pre-post tests and demographic surveys were analyzed. Descriptive statistics are provided. Pre-post test evaluations included 25 evidence-based clinically related questions about RR-TB diagnosis, treatment, and care.. Participants (N = 842) participated in testing, and matched evaluations were received for 800 (95.0%) training participants. Demographic data were available for 793 (99.13%) participants, of whom 762 (96.1%) were MOs, or nurses, either PN or APPNs. Average correct response pre-test and post-test scores were 61.7% (range 7-24 correct responses) and 85.9% (range 12-25), respectively. Overall, 95.8% (730/762) of participants demonstrated improved knowledge. PNs improved on average 25% (6.22 points), whereas MOs improved 10% (2.89 points) with better mean test scores on both pre- and post-test (p < 0.000). APPNs performed the same as the MOs on post-test scores (p = NS).. The inter-professional training program in short-course RR-TB treatment improved knowledge for participants. MOs had significantly greater pre-test scores. Of the nurses, APPNs outperformed other PNs, and performed equally to MOs on post-test scores, suggesting this advanced cadre of nurses might be the most appropriate to initiate and monitor treatment in close collaboration with MOs. All cadres of nurse reported the need for additional clinical training and mentoring prior to managing such patients.

Topics: Delivery of Health Care; Humans; Rifampin; South Africa; Tuberculosis, Multidrug-Resistant; Workforce

The Republic of Moldova is among the 30 Rifampicin-Resistant and/or Multidrug-Resistant (RR/MDR) Tuberculosis (TB) high burden countries in the world. Despite free TB diagnostics and treatment, TB patients face substantial economic losses and this may impact overall treatment outcomes. We assessed if there is an association between TB-related catastrophic costs and TB treatment outcomes. We conducted a cohort study using data from patient records and a survey that quantified catastrophic costs among RR/MDR-TB affected households in the Republic of Moldova in 2016. We included adult patients (age ≥18 years) with RR/MDR-TB who had been in inpatient (intensive phase) or outpatient (continuous phase) treatment for at least 2 months. Unfavourable treatment outcome, such as failure, death or lost to follow-up, was the primary outcome variable. The definition of catastrophic TB-related costs followed the World Health Organisation (WHO) guidelines: costs due to TB ≥20% of annual household income. Log-binomial regression was used to assess association between the outcome and catastrophic TB-related costs adjusting for other socio-demographic, behavioural and clinical covariates.  In total 287 RR/MDR-TB patients (78% males, mean age 42 years) were included. Of them, 30% experienced catastrophic TB-related costs. Overall, one in five patients (21%) had unfavourable treatment outcome, such as treatment failure (5%), death (8%) or lost to follow-up (8%). The experience of catastrophic TB-related costs was not associated with unfavourable treatment outcome [adjusted relative risk (aRR)=0.88, 95% CI: 0.50-1.50]. Major factors independently associated with unfavourable TB treatment outcomes were poverty (aRR=2.07; 95% CI: 1.06-4.07), urban residence (aRR=1.99; 95% CI: 1.12-3.52) and positive HIV (Human Immunodeficiency Virus) status (aRR=2.61; 95% CI: 1.31-4.89). As a result, we failed to find an association between catastrophic costs and treatment outcomes of RR/MDR-TB patients in the Republic of Moldova. However, we found that patients from poor households and urban areas were twice more likely to achieve unfavourable TB treatment outcomes disregarding whether they experienced catastrophic costs or not. Also, TB/HIV patients and urban residents were identified as the most vulnerable groups with higher risk of unfavourable treatment outcome and TB-related costs.

Topics: Adolescent; Adult; Cohort Studies; Female; HIV Infections; Humans; Male; Moldova; Rifampin; Treatment Outcome; Tuberculosis; Tuberculosis, Multidrug-Resistant

Considering the complexity of second-line anti-tuberculosis (TB) treatment regimens, the management of drug-resistant TB (DR-TB) in Georgia remains a major challenge. Since the introduction of new and repurposed anti-TB medications, the implementation of active TB Drug Safety Monitoring (aDSM) was a critical program component to help establish safety and manage all treatment related Serious Adverse Events (SAEs). In our study, we aimed to describe the occurrence, characteristics and timing of SAE among patients with Rifampicin Resistant and Multi-Drug Resistant TB (RR/MDR-TB) receiving new and/or repurposed anti-TB medications (bedaquiline, delamanid, linezolid, clofazimine, imipenem) during the period of 2016-2018 in Georgia and identify predictors of SAE. The data were obtained from the medical charts, electronic database and standardized aDSM reports During 2016-2018 period in total 970 people with RR/MDR-TB were notified in Georgia and 388 of them received new and/or repurposed TB drugs as part of their treatment regimen and all were included into the study. The results showed a total of 73 SAEs registered among 49 (12.6%) patients receiving new and/or repurposed drugs. The overall SAE incidence rate per 100 person-months was 1.16. The severity of the majority of the SAEs (46.6%) was grade III and 21.9% were grade IV. The most common SAE reported was hepatotoxicity, with an incidence of 0.26 per 100 person-month (n=16, 21.9%) followed by cardiotoxicity with an incidence of 0.16 per 100 person-month (n=10, 13.7%). Median time to SAE occurrence was 183 days (IQR 84 - 334) after treatment initiation. Resistance profile was the only predictor associated with occurrence of a SAEs. There was increased hazard of SAEs among patients with XDR-TB (adjusted HR=2.18, 95% CI: 1.12-4.23). Our findings on SAEs among patients treated with new or repurposed anti-TB drugs are echoing the findings available in the literature. They highlight the need for close monitoring of patients and underlines the importance of the aDSM during the whole treatment. Safety profile of the medications and combinations used are yet to be established and larger datasets comprised of patients receiving same treatment regimens need to be utilized.

Topics: Antitubercular Agents; Georgia; Humans; Incidence; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

The global proportion of successful treatment outcomes of Multidrug-Resistant/Rifampicin-Resistant Tuberculosis (MDR/RR-TB) remains unacceptably low. Time to culture conversion is important in making treatment-related decisions and is used as an interim predictor of pulmonary MDR/RR-TB treatment success. No previous studies have been conducted to assess determinants of time to culture conversion for MDR/RR-TB patients in Lithuania. Secondary analysis of data of culture-positive MDR/RR-TB patients, treated in Republican Klaipeda Hospital between 1st July 2016 and 1st July 2019 was performed. Culture conversion was defined as two consecutive negative cultures on solid media submitted at least 30 days apart. Factors associated with culture conversion were estimated by crude and multivariable Cox regression accounting for competing risks. In total, 115 consecutive patients starting treatment were included in the study. Of them, the majority was male (86/115; 74.8%) with a mean age of 48 (standard deviation (SD) ±12) years and Human Immunodeficiency Virus (HIV) negative (105/115; 91.3%). Nearly two-thirds (72/115; 62.6%) had XDR (extensive drug resistance) or MDR/RR-TB with additional resistance to second-line injectables or fluoroquinolones. Of 115 culture-positive patients at baseline, 103 (89.6%) patients achieved culture conversion during 12 months of treatment. The median time to culture conversion was 1.1 months (interquartile range: 0.9-1.8). Patients aged ≥60 years compared with <40 years [adjusted hazard ration (aHR): 0.40, 95% confidence interval (CI): 0.18-0.86], smokers (aHR: 0.39, 95% CI: 0.2-0.73), patients with positive sputum smear microscopy at baseline (aHR: 0.40, 95% CI: 0.25-0.63), cavities on initial chest X-ray (aHR: 0.56, 95% CI: 0.35-0.88) and resistance to at least one fluoroquinolone drug (aHR: 0.52, 95% CI: 0.32-0.84) were slower to culture convert. In conclusion, we recommend providing additional counseling, treatment adherence interventions and scale up the use of new and repurposed TB drugs to patient groups at risk of worse interim treatment outcome: patients aged 60 and above, with resistance to fluoroquinolones, smear-positive, smokers, or with signs of extensive disease evident on initial chest radiography.

Topics: Antitubercular Agents; Cohort Studies; Humans; Lithuania; Male; Middle Aged; Retrospective Studies; Rifampin; Sputum; Treatment Outcome; Tuberculosis, Multidrug-Resistant

Rifampicin-Resistant/Multidrug-Resistant Tuberculosis (RR/MDR-TB) is recognized as a major public health concern globally. In Armenia, the proportion of RR/MDR-TB is increasing among all people affected with TB. We conducted a nationwide cohort study involving analysis of programmatic data to investigate the rates of and factors associated with unfavourable treatment outcomes among patients with RR/MDR-TB registered by the national TB programme from 2014 to 2017 in Armenia. We used Cox regression to identify factors associated with the outcome. Among 451 RR/MDR-TB patients, 80% were men and median age was 46 years. Of them, 53 (11.8%) had Extensively Drug-Resistant Tuberculosis (XDR-TB) and 132 (29.3%) had pre-XDR-TB. Almost half (224, 49.7%) of the patients had unfavourable treatment outcome, which included 26.8% Loss To Follow-Up (LTFU), 13.3% failures and 9.5% deaths. In multivariable analysis, people with pre-XDR-TB [adjusted Hazard Ratio [aHR] 3.13, 95% confidence intervals [CI] 2.16-4.55] and XDR-TB (aHR 4.08, 95% CI 2.45-6.79) had a higher risk of unfavourable outcomes. Patients receiving home-based treatment (71/451, 15.7%) and treatment with new drugs (172/451, 38.1%) had significantly lower risk (aHR 0.45, 95% CI 0.28-0.72 and aHR 0.26, 95% CI 0.18-0.39) of unfavourable treatment outcome.  The proportion of MDR-TB patients reaching favourable treatment outcome in Armenia was substantially lower than the recommended level (75%). The most common treatment outcome was LTFU indicating the need for further assessment of underlying determinants. Home-based treatment looks promising and future studies are required to see if expanding it to all RR/MDR-TB patients is feasible and cost-effective.

Topics: Antitubercular Agents; Armenia; Cohort Studies; Humans; Male; Middle Aged; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant

Mental health comorbidities are common among tuberculosis patients, with higher prevalence among people with rifampicin-resistant/multidrug-resistant (RR/MDR) tuberculosis.  TB and depression share common risk factors adding to the overall disease burden. There is limited evidence about prevalence of depression and anxiety symptoms among tuberculosis patients in Romania. We assessed the prevalence of depression and anxiety symptoms and their evolution over the course of the treatment in RR/MDR-TB patients receiving in-patient care at the National Institute of Pneumonology (NIP) "Marius Nasta" in Romania during May-September 2020. We conducted a cohort study and used the Hospital Anxiety and Depression Scale (HADS) to assess the prevalence of depression and anxiety (defined as score≥ 8) symptoms at admission (baseline) and the second month of in-patient treatment (follow-up). Difference between baseline and follow-up depression and anxiety symptoms were assessed using McNemar test. Binary logistic regression was used to evaluate the association between sociodemographic and clinical characteristics with the presence of depression and anxiety symptoms at baseline. The cohort included 46 patients, 63% were male, mean age was 46 (±13.3) years. The prevalence of depression and anxiety in our cohort was 46% and 43% at baseline respectively, and 50% and 39%, at the follow-up respectively. About one third (7/25) of patients who had normal HADS depression score at baseline, had an increase above the threshold at the second month of treatment. No statistical difference in prevalence of depression or anxiety was found between the baseline and second month of treatment. Unadjusted analysis showed that odds of depression at baseline was lower in patients with education above 8th grade compared to patients with education below 8th grade (odds ratio=0.2, 95% confidence interval: 0.1,0.8, p=0.026). The study revealed high prevalence of depression and anxiety among RR/MDR-TB patients admitted to the NIP, underlining the necessity of evaluating the mental health of TB patients and linking them to appropriate care.

Topics: Anxiety; Cohort Studies; Depression; Humans; Male; Middle Aged; Patient Care; Pulmonary Medicine; Rifampin; Romania; Tuberculosis, Multidrug-Resistant

Multidrug-resistant tuberculosis (MDR-TB) poses a serious challenge to TB control. It is of great value to search for drug resistance mutation sites and explore the roles that they play in the diagnosis and prognosis of MDR-TB.. We consecutively enrolled MDR-TB patients from five cities in Jiangsu Province, China, between January 2013 and December 2014. Drug susceptibility tests of rifampin, isoniazid, ofloxacin, and kanamycin were routinely performed by proportion methods on Lowenstein-Jensen (LJ) medium. Drug resistance-related genes were sequenced, and the consistency of genetic mutations and phenotypic resistance was compared. The association between mutations and treatment outcomes was expressed as odds ratios (ORs) and 95% confidence intervals (CIs).. Among 87 MDR-TB patients, 71 with treatment outcomes were involved in the analysis. The proportion of successful treatment was 50.7% (36/71). The rpoB gene exhibited the highest mutation rate (93.0%) followed by katG (70.4%), pncA (33.8%), gyrA (29.6%), eis (15.5%), rrs (12.7%), gyrB (9.9%) and rpsA (4.2%). Multivariable analysis demonstrated that patients with pncA gene mutations (adjusted OR: 19.69; 95% CI: 2.43-159.33), advanced age (adjusted OR: 13.53; 95% CI: 1.46-124.95), and nonstandard treatment (adjusted OR: 7.72; 95% CI: 1.35-44.35) had a significantly higher risk of poor treatment outcomes.. These results suggest that Mycobacterium tuberculosis gene mutations may be related to phenotypic drug susceptibility. The pncA gene mutation along with treatment regimen and age are associated with the treatment outcomes of MDR-TB.

Topics: Acetyltransferases; Adult; Amidohydrolases; Antitubercular Agents; Bacterial Proteins; Catalase; China; DNA Gyrase; DNA-Directed RNA Polymerases; Drug Resistance, Multiple, Bacterial; Female; Humans; Isoniazid; Kanamycin; Male; Middle Aged; Multivariate Analysis; Mutation; Mutation Rate; Mycobacterium tuberculosis; Odds Ratio; Ofloxacin; Prospective Studies; Rifampin; Sequence Analysis, DNA; Treatment Outcome; Tuberculosis, Multidrug-Resistant

Stigma contributes to diagnostic delay, disease concealment, and reduced wellbeing for people with multidrug-resistant tuberculosis (MDR-TB) and their communities. Despite the negative effects of stigma, there are no scales to measure stigma in people with MDR-TB. This study aimed to develop and validate a scale to measure stigma in people affected by MDR-TB in Vietnam.. People with rifampicin-resistant (RR)-MDR-TB who had completed at least 3 months of treatment were invited to complete a survey containing 45 draft stigma items. Data analysis included exploratory factor analysis, internal consistency, content, criterion and construct validity, and test-retest reliability.. A total of 315 people with RR/MDR-TB completed the survey. Exploratory factor analysis revealed a 14 item RR/MDR-TB stigma scale with four subscales, including guilt, social exclusion, physical isolation, and blame. Internal consistency and test-retest reliability were good (Cronbach's Alpha = 0.76, ICC = 0.92). Construct validity was adequate with moderate correlations with related constructs.. Our RR/MDR-TB Scale demonstrated good psychometric properties in Vietnam. This scale will assist in the measurement of stigma in people with RR/MDR-TB. It will also aid in the evaluation of stigma reduction interventions in people with RR/MDR-TB.

Topics: Adult; Antibiotics, Antitubercular; Cross-Sectional Studies; Female; Humans; Male; Middle Aged; Psychometrics; Quality of Life; Reproducibility of Results; Rifampin; Social Stigma; Surveys and Questionnaires; Tuberculosis, Multidrug-Resistant; Vietnam

Treatment monitoring of drug-resistant tuberculosis (DR-TB) in resource-limited settings is challenging. We developed a multi-analyte assay for eleven anti-TB drugs in small hair samples as an objective metric of drug exposure.. Small hair samples were collected from participants at various timepoints during directly observed RR-TB treatment at an inpatient tertiary referral facility in South Africa (DR-TB cohort). We assessed qualitative determination (i.e., detection above limit of detection) of bedaquiline, linezolid, clofazimine, pretomanid, levofloxacin, moxifloxacin, pyrazinamide, isoniazid, ethambutol, ethionamide, and prothionamide in an LC-MS/MS index panel assay against a reference standard of inpatient treatment records. Because treatment regimens prior to hospitalization were not available, we also analyzed specificity (for all drugs except isoniazid) using an external cohort of HIV-positive patients treated for latent TB infection with daily isoniazid (HIV/LTBI cohort) in Uganda.. Among the 57 DR-TB patients (58% with pre-XDR/XDR-TB; 70% HIV-positive) contributing analyzable hair samples, the sensitivity of the investigational assay was 94% or higher for all drugs except ethionamide (58.5, 95% confidence interval [CI], 40.7-99.9). Assay specificity was low across all tested analytes within the DR-TB cohort; conversely, assay specificity was 100% for all drugs in the HIV/LTBI cohort.. Hair drug concentrations reflect long-term exposure, and multiple successive regimens commonly employed in DR-TB treatment may result in apparent false-positive qualitative and falsely elevated quantitative hair drug levels when prior treatment histories within the hair growth window are not known.

Topics: Adult; Antitubercular Agents; Chromatography, Liquid; Drug Monitoring; Female; Hair; Humans; Male; Middle Aged; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tandem Mass Spectrometry; Tuberculosis; Tuberculosis, Multidrug-Resistant

We present a case of a patient in Mozambique, who initiated treatment for rifampicin-resistant tuberculosis (RR-TB) without proof of resistance. For this patient, we estimated the probability of RR-TB using likelihood ratios of clinical arguments. The probability of RR-TB in Mozambique, positive HIV status, and treatment failure after a first treatment and after retreatment were included as confirming arguments, and a rapid molecular test showing rifampicin susceptibility as excluding argument. The therapeutic threshold to start treatment for RR-TB is unknown, but probably lower than 47% and should be calculated to guide clinical decisions.

Topics: Adult; Antitubercular Agents; Female; HIV Infections; Humans; Mozambique; Mycobacterium tuberculosis; Rifampin; Treatment Failure; Tuberculosis, Multidrug-Resistant

Treatment of rifampin-monoresistant/multidrug-resistant Tuberculosis (RR/MDR-TB) requires long treatment courses, complicated by frequent adverse events and low success rates. Incidence of RR/MDR-TB in Canada is low and treatment practices are variable due to the infrequent experience and challenges with drug access. We undertook a retrospective cohort study of all RR/MDR-TB cases in Alberta, Canada from 2007-2017 to explore the epidemiology and outcomes in our low incidence setting. We performed a descriptive analysis of the epidemiology, treatment regimens and associated outcomes, calculating differences in continuous and discrete variables using Student's t and Chi-squared tests, respectively. We identified 24 patients with RR/MDR-TB. All patients were foreign-born with the median time to presentation after immigration being 3 years. Prior treatment was reported in 46%. Treatment was individualized. All patients achieved sputum culture conversion within two months of treatment initiation. The median treatment duration after culture conversion was 18 months (IQR: 15-19). The mean number of drugs utilized during the intensive phase was 4.3 (SD: 0.8) and during the continuation phase was 3.3 (SD: 0.9) and the mean adherence to medications was 95%. Six patients completed national guideline-concordant therapy, with many patients developing adverse events (79%). Treatment success (defined as completion of prescribed therapy or cure) was achieved in 23/24 patients and no acquired drug resistance or relapse was detected over 1.8 years of median follow-up. Many cases were captured upon immigration assessment, representing important prevention of community spread. Despite high rates of adverse events and short treatment compared to international guidelines, success in our cohort was very high at 96%. This is likely due to individualization of therapy, frequent use of medications with high effectiveness, intensive treatment support, and early sputum conversion seen in our cohort. There should be ongoing exploration of treatment shortening with well-tolerated, efficacious oral agents to help patients achieve treatment completion.

Topics: Adult; Alberta; Antitubercular Agents; Emigration and Immigration; Female; Humans; Incidence; Male; Middle Aged; Retrospective Studies; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Young Adult

This study aimed to evaluate whether the antibiotic fidaxomicin has

Topics: Antitubercular Agents; Bacterial Proteins; Drug Resistance, Multiple, Bacterial; Fidaxomicin; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Multidrug-resistant (MDR) tuberculosis has low treatment success rates, and new treatment strategies are needed. We explored whether treatment with active vitamin D3 (vitD) and phenylbutyrate (PBA) could improve conventional chemotherapy by enhancing immune-mediated eradication of Mycobacterium tuberculosis.. A clinically relevant model was used consisting of human macrophages infected with M. tuberculosis isolates (n = 15) with different antibiotic resistance profiles. The antimicrobial effect of vitD+PBA, was tested together with rifampicin or isoniazid. Methods included colony-forming units (intracellular bacterial growth), messenger RNA expression analyses (LL-37, β-defensin, nitric oxide synthase, and dual oxidase 2), RNA interference (LL-37-silencing in primary macrophages), and Western blot analysis and confocal microscopy (LL-37 and LC3 protein expression).. VitD+PBA inhibited growth of clinical MDR tuberculosis strains in human macrophages and strengthened intracellular growth inhibition of rifampicin and isoniazid via induction of the antimicrobial peptide LL-37 and LC3-dependent autophagy. Gene silencing of LL-37 expression enhanced MDR tuberculosis growth in vitD+PBA-treated macrophages. The combination of vitD+PBA and isoniazid were as effective in reducing intracellular MDR tuberculosis growth as a >125-fold higher dose of isoniazid alone, suggesting potent additive effects of vitD+PBA with isoniazid.. Immunomodulatory agents that trigger multiple immune pathways can strengthen standard MDR tuberculosis treatment and contribute to next-generation individualized treatment options for patients with difficult-to-treat pulmonary tuberculosis.

Topics: Antibiotics, Antitubercular; Antimicrobial Peptides; Cells, Cultured; Cholecalciferol; Humans; Immunomodulating Agents; Isoniazid; Macrophages; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Drug susceptibility testing (DST) patterns of Mycobacterium tuberculosis (MTB) from patients with rifampicin-resistant tuberculosis (RR-TB) or multidrug-resistant TB (MDR-TB; or resistant to rifampicin and isoniazid (INH)), are important to guide preventive therapy for their household contacts (HHCs).. As part of a feasibility study done in preparation for an MDR-TB preventive therapy trial in HHCs, smear, Xpert MTB/RIF, Hain MTBDRplus, culture and DST results of index MDR-TB patients were obtained from routine TB programs. A sputum sample was collected at study entry and evaluated by the same tests. Not all tests were performed on all specimens due to variations in test availability.. Three hundred eight adults with reported RR/MDR-TB were enrolled from 16 participating sites in 8 countries. Their median age was 36 years, and 36% were HIV-infected. Routine testing on all 308 were confirmed as having RR-TB, but only 75% were documented as having MDR-TB. The majority of those not classified as having MDR-TB were because only rifampicin resistance was tested. At study entry (median 59 days after MDR-TB treatment initiation), 280 participants (91%) were able to produce sputum for the study, of whom 147 (53%) still had detectable MTB. All but 2 of these 147 had rifampicin DST done, with resistance detected in 89%. Almost half (47%) of the 147 specimens had INH DST done, with 83% resistance. Therefore, 20% of the 280 study specimens had MDR-TB confirmed. Overall, DST for second-line drugs were available in only 35% of the 308 routine specimens and 15% of 280 study specimens.. RR-TB was detected in all routine specimens but only 75% had documented MDR-TB, illustrating the need for expanded DST beyond Xpert MTB/RIF to target preventive therapy for HHC.

Topics: Adult; Antitubercular Agents; Cross-Sectional Studies; Feasibility Studies; Female; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant

Regardless of a plethora of advanced diagnostics, TB and drug resistance remains a principal killer. We proposed gold nanoparticles (AuNPs) attached with probes to enhance the efficiency of GeneXpert MTB/RIF assay instead of conventional dye probes for molecular detection. A total of 15,000 samples were collected from TB suspects and subjected to Xpert MTB/RIF assay, where 6800 (45.3%) were detected as MTB positive, 280 (4.3%) were detected to harbor mutations in the RRDR, while invalid /errors were found in 690 (4.6%) cases. The mutations were detected by probe E, 199 (71.1%), while probes B and D, 30 and 26 (10% and 9%), respectively. In the Xpert MTB/RIF Assay were found mutations picked by probes E and B codons 529-533 (71%) and 512-518 (10%), respectively. The fast-rising works of TB nano-diagnostics, of Xpert probes, may improve by the applications of gold nanoparticle probes.

Topics: Antibiotics, Antitubercular; Codon; Drug Resistance, Multiple, Bacterial; Gold; Humans; Metal Nanoparticles; Molecular Probes; Mutation; Mycobacterium tuberculosis; Pakistan; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Topics: Antibiotics, Antitubercular; Bacterial Proteins; DNA Mutational Analysis; DNA-Directed RNA Polymerases; Drug Resistance, Multiple, Bacterial; Genotype; Humans; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Point-of-Care Testing; Predictive Value of Tests; Reproducibility of Results; Rifampin; Tuberculosis, Multidrug-Resistant

We present a case of a 59-year-old man, who on being evaluated for abdominal pain and headache, was found to have a pancreatic head mass and inflammatory hypophysitis. Xpert MTB/Rif of the pancreatic mass biopsy showed the presence of tuberculosis (TB) with a very low load, and rifampicin resistance was detected with absence of probes A and B. Pyrosequencing (a novel genotypic test for TB) of the Xpert MTB/Rif isolate detected a single, rare, high-confidence mutation (S512T) in the rpoB region (rifampicin resistance determining region in the MTB genome). The TB mycobacteria growth indicator tube (TBMGIT) phenotypic drug susceptibility test (DST), however, showed rifampicin susceptibility. Incidentally, he was unable to tolerate rifampicin and responded well to a non-rifampicin-based regimen. We discuss a possible hypothesis of the Xpert-DST discordance in accordance with a recent literature review on phenotypic DST methods. We also discuss the utility of pyrosequencing in clinical practice for the diagnosis of TB and its resistance patterns.

Topics: Antibiotics, Antitubercular; Drug Resistance, Bacterial; Humans; Male; Middle Aged; Mutation; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis; Tuberculosis, Multidrug-Resistant

Tuberculosis (TB) is the leading infectious cause of death in the world. Multi-drug resistant TB (MDR-TB) is a major public health problem as treatment is long, costly, and associated to poor outcomes. Here, we report epidemiological data on the prevalence of drug-resistant TB in Haiti.. This cross-sectional prevalence study was conducted in five health centers across Haiti. Adult, microbiologically confirmed pulmonary TB patients were included. Molecular genotyping (rpoB gene sequencing and spoligotyping) and phenotypic drug susceptibility testing were used to characterize rifampin-resistant MTB isolates detected by Xpert MTB/RIF.. Between April 2016 and February 2018, 2,777 patients were diagnosed with pulmonary TB by Xpert MTB/RIF screening and positive MTB cultures. A total of 74 (2.7%) patients were infected by a drug-resistant (DR-TB) M. tuberculosis strain. Overall HIV prevalence was 14.1%. Patients with HIV infection were at a significantly higher risk for infection with DR-TB strains compared to pan-susceptible strains (28.4% vs. 13.7%, adjusted odds ratio 2.6, 95% confidence interval 1.5-4.4, P = 0.001). Among the detected DR-TB strains, T1 (29.3%), LAM9 (13.3%), and H3 (10.7%) were the most frequent clades. In comparison with previous spoligotypes studies with data collected in 2000-2002 and in 2008-2009 on both sensitive and resistant strains of TB in Haiti, we observed a significant increase in the prevalence of the drug-resistant MTB Spoligo-International-Types (SIT) 137 (X2 clade: 8.1% vs. 0.3% in 2000-02 and 0.9% in 2008-09, p<0.001), 5 (T1 clade: 6.8% vs 1.9 in 2000-02 and 1.7% in 2008-09, P = 0.034) and 455 (T1 clade: 5.4% vs 1.6% and 1.1%, P = 0.029). Newly detected spoligotypes (SIT 6, 7, 373, 909 and 1624) were also recorded.. This study describes the genotypic and phenotypic characteristics of DR-TB strains circulating in Haiti from April 2016 to February 2018. Newly detected MTB clades harboring multi-drug resistance patterns among the Haitian population as well as the higher risk of MDR-TB infection in HIV-positive people highlights the epidemiological relevance of these surveillance data. The importance of detecting RIF-resistant patients, as proxy for MDR-TB in peripheral sites via molecular techniques, is particularly important to provide adequate patient case management, prevent the transmission of resistant strains in the community and to contribute to the surveillance of resistant strains.

Topics: Adult; Antitubercular Agents; Coinfection; Cross-Sectional Studies; Drug Resistance, Multiple, Bacterial; Female; Haiti; HIV Infections; Humans; Isoniazid; Male; Mass Screening; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Prevalence; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant; Young Adult

Topics: Antibiotics, Antitubercular; Human Rights; Humans; Rifampin; Tuberculosis, Multidrug-Resistant

Topics: Antibiotics, Antitubercular; Human Rights; Humans; Rifampin; Tuberculosis, Multidrug-Resistant

The laboratory plays a critical role in tuberculosis (TB) control by providing testing for diagnosis, treatment monitoring, and surveillance at each level of the health care system. Weak accessibility to TB diagnosric services still represents a big concern in many limited resources' countries. Here we report the experience of Burkina Faso in implementing a comprehensive intervention packages to strengthen TB laboratory capacity and diagnostic accessibility.. The intervention lasted from October 2016 to December 2018 and focused on two main areas: i) development of strategic documents and policies; ii) implementation of TB diagnostic technology. National TB laboratory data were collected between 2016 and 2018 and evaluated according to five programmatic TB laboratory indicators: i) Percentage of notified new and relapse TB cases with bacteriological confirmation; ii) Percentage of notified new and relapse TB cases tested by Xpert MTB/RIF; iii) Percentage of notified, bacteriologically confirmed TB cases with a drug susceptibility testing (DST) result for rifampin; iv) Percentage of notified MDR-TB cases on the estimated number of MDR-TB cases; v) The ration between the number of smear microscopy and Xpert MTB/RIF tests. We compared these indicators between a 1 year (2016-2017) and 2 years (2016-2018) timeframe.. From 2016 to 2018, the percentage of bacteriologically confirmed cases increased from 67 to 71%. The percentage of new and relapse TB cases notified tested by Xpert MTB/RIF increased from 18% in 2016 to 46% in 2018 and the percentage of bacteriologically confirmed cases with an available DST result for rifampicin increased from 27% in 2016 to 66% in 2018.. The percentage of notified MDR-TB cases on the estimated number of MDR-TB cases in 2018 increased from 43% in 2016 to 78% in 2018. In 2018, the ratio between the number of smear microscopy and Xpert MTB/RIF tests decreased from 53% in 2016 to 21% in 2018.. We demonstrated that the implementation of a comprehensive package of laboratory strengthening interventions led to a significant improvement of all indicators. External technical assistance played a key role in speeding up the TB laboratory system improvement process.

Topics: Antibiotics, Antitubercular; Burkina Faso; Humans; International Cooperation; Laboratories; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Reagent Kits, Diagnostic; Recurrence; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

The prevalence of drug-resistant

Topics: Adolescent; Adult; Aged; Antitubercular Agents; DNA, Bacterial; Female; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Microbiota; Middle Aged; Mycobacterium tuberculosis; Rifampin; RNA, Ribosomal, 16S; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

Multidrug- and rifampicin (RMP)-resistant tuberculosis (MDR/RR-TB) requires prolonged and expensive treatment, which is difficult to sustain in the Colombian health system. This requires the joint action of different providers to provide timely health services to people with TB. Identifying factors associated with unfavorable treatment outcomes in patients with MDR/RR-TB who received drug therapy between 2013 and 2015 in Colombia can help guide the strengthening of the national TB control program.. A retrospective cohort study was conducted with all patients who received treatment for MDR/RR-TB between January 2013 and December 2015 in Colombia who were registered and followed up by the national TB control program. A multivariate logistic regression model was used to estimate the associations between the exposure variables with the response variable (treatment outcome).. A total of 511 patients with MDR/RR-TB were registered and followed up by the national TB control program in Colombia, of whom 16 (3.1%) had extensive drug resistance, 364 (71.2%) had multidrug resistance, and 131 (25.6%) had RMP monoresistance. The mean age was 39.9 years (95% confidence interval (CI): 38.5-41.3), most patients were male 285 (64.6%), and 299 (67.8%) were eligible for subsidized health services. The rate of unfavorable treatment outcomes in the RR-TB cohort was 50.1%, with rates of 85.7% for patients with extensive drug resistance, 47.6% for patients with multidrug resistance, and 52.6% for patients with RMP monoresistance. The 511 MDR/RR-TB patients were included in bivariate and multivariate analyses, patients age ≥ 60 years (crude odds ratio (ORc) = 2.4, 95% CI 1.1-5.8; adjusted odds ratio (ORa) = 2.7, 95% CI 1.1-6.8) and subsidized health regime affiliation (ORc = 3.6, 95% CI 2.3-5.6; ORa = 3.4, 95% CI 2.0-6.0) were associated with unfavorable treatment outcomes.. More than 50% of the patients with MDR/RR-TB in Colombia experienced unfavorable treatment outcomes. The patients who were eligible for subsidized care were more likely to experience unfavorable treatment outcomes. Those who were older than 60 years were also more likely to experience unfavorable treatment outcomes.

Topics: Adult; Aged; Antitubercular Agents; Colombia; Female; Humans; Logistic Models; Male; Middle Aged; Prognosis; Public Health; Retrospective Studies; Rifampin; Risk Assessment; Treatment Outcome; Tuberculosis, Multidrug-Resistant

Treatment of drug-resistant tuberculosis is lengthy, insufficiently effective, and toxic. Since 2016, the World Health Organization has recommended shorter treatment regimens (STR). We assessed effectiveness and predictors of drug adverse events (DAE) among patients treated with STR. There were 95 consecutive rifampicin-resistant patients enrolled in STR in Tashkent between June 2018 and September 2019. Of these, 66.3% were successfully treated, 17.9% suffered failed treatment, 7.4% died, 5.3% were lost to follow-up and 3.2% were not evaluated. No recurrence was identified in 54 patients after 12 months of successful treatment completion. There were 47 reported DAE: the incidence rate was 6.15 DAE per 100 person-months-of-treatment. Any DAE was reported in 38 (40%) patients and grade 3/4 DAE were recorded in 21 (22.1%) patients. Median time to DAE was 101 (interquartile range 64-139) days. The most frequently encountered DAE were gastro-intestinal disorders, followed by hepatotoxicity and ototoxicity. The most commonly offending drug inducing DAE was protionamide. The dose was temporarily interrupted in 55.3% of DAE, reduced in 8.5% of DAE and permanently withdrawn in another 8.5% of DAE. HIV status was the only predictor associated with increased hazard of DAE. In Uzbekistan STR showed moderate effectiveness and safety, although treatment failure was high.

Topics: Antitubercular Agents; Clinical Protocols; Humans; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Uzbekistan

Uzbekistan has a large burden of drug-resistant tuberculosis (TB). To deal with this public health threat, the National TB Program introduced rapid molecular diagnostic tests such as Xpert MTB/RIF (Xpert) and line probe assays (LPAs) for first-line and second-line drugs. We documented the scale-up of Xpert and LPAs from 2012-2019 and assessed whether this led to an increase in patients with laboratory-confirmed multidrug-resistant/rifampicin-resistant TB (MDR/RR-TB) and extensively drug-resistant TB (XDR-TB). This was a descriptive study using secondary program data. The numbers of GeneXpert instruments cumulatively increased from six to sixty-seven, resulting in annual assays increasing from 5574 to 107,330. A broader use of the technology resulted in a lower proportion of tests detecting

Topics: Drug Resistance, Bacterial; Humans; Mycobacterium tuberculosis; Pathology, Molecular; Rifampin; Tuberculosis, Multidrug-Resistant; Uzbekistan

Whole-genome sequencing has shown that the Mycobacterium tuberculosis infection process can be more heterogeneous than previously thought. Compartmentalized infections, exogenous reinfections, and microevolution are manifestations of this clonal complexity. The analysis of the mechanisms causing the microevolution -the genetic variability of M. tuberculosis at short time scales- of a parental strain into clonal variants with a patient is a relevant issue that has not been yet completely addressed. To our knowledge, a whole genome sequence microevolution analysis in a single patient with inadequate adherence to treatment has not been previously reported.. In this work, we applied whole genome sequencing analysis for a more in-depth analysis of the microevolution of a parental Mycobacterium tuberculosis strain into clonal variants within a patient with poor treatment compliance in Argentina. We analyzed the whole-genome sequence of 8 consecutive Mycobacterium tuberculosis isolates obtained from a patient within 57-months of intermittent therapy. Nineteen mutations (9 short-term, 10 fixed variants) emerged, most of them associated with drug resistance. The first isolate was already resistant to isoniazid, rifampicin, and streptomycin, thereafter the strain developed resistance to fluoroquinolones and pyrazinamide. Surprisingly, isolates remained susceptible to the pro-drug ethionamide after acquiring a frameshift mutation in ethA, a gene required for its activation. We also found a novel variant, (T-54G), in the 5' untranslated region of whiB7 (T-54G), a region allegedly related to kanamycin resistance. Notably, discrepancies between canonical and phage-based susceptibility testing to kanamycin were previously found for the isolate harboring this mutation. In our patient, microevolution was mainly driven by drug selective pressure. Rare short-term mutations fixed together with resistance-conferring mutations during therapy.. This report highlights the relevance of whole-genome sequencing analysis in the clinic for characterization of pre-XDR and MDR resistance profile, particularly in patients with incomplete and/or intermittent treatment.

Topics: Adult; Antitubercular Agents; Argentina; Drug Resistance, Multiple, Bacterial; Female; Humans; Isoniazid; Medication Adherence; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Phylogeny; Pyrazinamide; Rifampin; Streptomycin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Whole Genome Sequencing

The continuous emergence of resistant Mycobacterium tuberculosis keeps tuberculosis (TB) treatment options still insufficient, and new therapeutic alternatives are urgently needed. Considering the antimycobacterial activity of phenazine derivatives previously reported by our research group, we aimed to explore possible applications to circumvent the resistance in M. tuberculosis. Firstly, we evaluated the antimicrobial activity of seven benzo[a]phenazine derivatives against eleven M. tuberculosis strains: ten resistant and one susceptible (H

Topics: Animals; Antitubercular Agents; Cell Survival; Chlorocebus aethiops; Drug Design; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Phenazines; Quantum Theory; Reactive Oxygen Species; Rifampin; Tuberculosis, Multidrug-Resistant; Vero Cells

Drug-resistant tuberculosis (DR-TB), including rifampicin-resistant tuberculosis (RR-TB) and multidrug-resistant tuberculosis (MDR-TB, or RR-TB with additional isoniazid resistance), presents challenges to TB control. In Uganda, the GeneXpert test provides point-of-care testing for TB and rifampicin resistance. Patients identified with RR-TB receive culture-based drug susceptibility testing (DST) to identify additional resistance, if any. There are few data on the epidemiological profiles of current DR-TB patients in Uganda. We described patients with RR-TB in Uganda and assessed the trends of RR-TB to inform TB control interventions.. We identified patients with RR-TB whose samples were referred for culture and DST during 2014-2018 from routinely-generated laboratory surveillance data at the Uganda National Tuberculosis Reference Laboratory. Data on patient demographics and drug sensitivity profile of Mycobacterium tuberculosis isolates were abstracted. Population data were obtained from the Uganda Bureau of Statistics to calculate incidence. Descriptive epidemiology was performed, and logistic regression used to assess trends.. We identified 1474 patients whose mean age was 36 ± 17 years. Overall incidence was 3.8/100,000 population. Males were more affected by RR-TB than females (4.9 vs. 2.7/100,000, p ≤ 0.01). Geographically, Northern Uganda was the most affected region (IR = 6.9/100,000) followed by the Central region (IR = 5.01/100,000). The overall population incidence of RR-TB increased by 20% over the evaluation period (OR = 1.2; 95% CI 1.15-1.23); RR-TB in new TB cases increased by 35% (OR = 1.35; 95% CI 1.3-1.4) and by 7% in previously-treated cases (OR = 1.07; 95% CI 1.0-1.1). Of the 1474 patients with RR-TB, 923 (63%) were culture-positive of whom 670 (72%) had full DST available. Based on the DST results, 522/670 (78%) had MDR-TB.. Between 2014 and 2018, the incidence of RR-TB increased especially among newly-diagnosed TB patients. We recommend intensified efforts and screening for early diagnosis especially among previously treated patients. Mechanisms should be in put to ensure that all patients with RR-TB obtain DST.

Topics: Adolescent; Adult; Aged; Antitubercular Agents; Child; Child, Preschool; Drug Resistance, Multiple, Bacterial; Female; Humans; Infant; Infant, Newborn; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant; Uganda; Young Adult

the emergence of HIV/TB co-infection has changed the global health landscape globally, particularly in sub-Saharan Africa and Asia with a high prevalence rate. It has further worsened and compound patient diagnosis, treatment/management approach and infection control. Rifampicin resistance TB (RR-TB) is a good indicator of treatment failure and infection control in the community. This study determines the prevalence of RR-TB among HIV/TB coinfected patients in Benue State, Nigeria.. the case-control study was carried out at Federal Medical Centre, Makurdi and General Hospital, Otupko, between January 2017 and February 2018. One thousand and ten suspected tuberculosis and HIV patients were enrolled in the study, diagnosed according to WHO guidelines. Sputum samples were collected and then analyzed by acid-fast bacilli smear test and GeneXpert MTB/RIF assay.. the relatively high prevalence of HIV/TB co-infection and RR-TB is a tremendous public health threat, considering society's attendant implication. Further surveillance studies are needed to evaluate the situation in Benue State better.

Topics: Adolescent; Adult; Antitubercular Agents; Case-Control Studies; Child; Child, Preschool; Coinfection; Female; HIV Infections; Humans; Infant; Infant, Newborn; Male; Middle Aged; Nigeria; Prevalence; Rifampin; Rural Population; Sputum; Tuberculosis; Tuberculosis, Multidrug-Resistant; Urban Population; Young Adult

Tuberculosis (TB), including multidrug-resistant (MDR; i.e., resistant to at least rifampicin and isoniazid)/rifampicin-resistant (MDR/RR) TB, is the most important opportunistic infection among people living with HIV (PLHIV). In 2005, Rwanda launched the programmatic management of MDR/RR-TB. The shorter MDR/RR-TB treatment regimen (STR) has been implemented since 2014. We analyzed predictors of MDR/RR-TB mortality, including the effect of using the STR overall and among PLHIV. This retrospective study included data from patients diagnosed with RR-TB in Rwanda between July 2005 and December 2018. Multivariable logistic regression was used to assess predictors of mortality. Of 898 registered MDR/RR-TB patients, 861 (95.9%) were included in this analysis, of whom 360 (41.8%) were HIV coinfected. Overall, 86 (10%) patients died during MDR/RR-TB treatment. Mortality was higher among HIV-coinfected compared with HIV-negative TB patients (13.3% versus 7.6%). Among HIV-coinfected patients, patients aged ≥ 55 years (adjusted odds ratio = 5.89) and those with CD4 count ≤ 100 cells/mm3 (adjusted odds ratio = 3.77) had a higher likelihood of dying. Using either the standardized longer MDR/RR-TB treatment regimen or the STR was not correlated with mortality overall or among PLHIV. The STR was as effective as the long MDR/RR-TB regimen. In conclusion, older age and advanced HIV disease were strong predictors of MDR/RR-TB mortality. Therefore, special care for elderly and HIV-coinfected patients with ≤ 100 CD4 cells/mL might further reduce MDR/RR-TB mortality.

Topics: Adult; Aged; Aged, 80 and over; Antitubercular Agents; Drug Resistance, Bacterial; Female; Forecasting; HIV Infections; Humans; Male; Middle Aged; Retrospective Studies; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant

The epidemic of pulmonary tuberculosis (TB), especially rifampin-resistant tuberculosis (RR-TB) presents a major challenge for TB control today. However, there is a lack of reliable and specific biomarkers for the early diagnosis of RR-TB. We utilized reverse transcription-quantitative polymerase chain reaction (RT-qPCR) to profile the transcript levels of 72 tripartite motif (TRIM) genes from a discovery cohort of 10 drug-sensitive tuberculosis (DS-TB) patients, 10 RR-TB patients, and 10 healthy controls (HCs). A total of 35 differentially expressed genes (DEGs) were screened out, all of which were down-regulated. The bio functions and pathways of these DEGs were enriched in protein ubiquitination, regulation of the viral process, Interferon signaling, and innate immune response, etc. A protein-protein interaction network (PPI) was constructed and analyzed using STRING and Cytoscape. Twelve TRIM genes were identified as hub genes, and seven (TRIM1, 9, 21, 32, 33, 56, 66) of them were verified by RT-qPCR in a validation cohort of 95 subjects. Moreover, we established the RR-TB decision tree models based on the 7 biomarkers. The receiver operating characteristic (ROC) analyses showed that the models exhibited the areas under the curve (AUC) values of 0.878 and 0.868 in discriminating RR-TB from HCs and DS-TB, respectively. Our study proposes potential biomarkers for RR-TB diagnosis, and also provides a new experimental basis to understand the pathogenesis of RR-TB.

Topics: Biomarkers; Gene Expression Profiling; Humans; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Molecular techniques have considerable advantages for rapid detection, a reduction of infectiousness, prevention of further resistance development and surveillance of drug-resistant TB. MTBDRsl VER 2.0 was used to detect resistance to second-line anti-tuberculosis drugs on 35 rifampicin-resistant M. tuberculosis (RR-MTB) isolates compared to the minimum inhibitory concentrations (MICs) and whole genome sequencing (WGS). The MTBDRsl VER 2.0 (Hain Life Science, Nehren, Germany) and WGS (San Diego, CA, USA) were performed for tracing mutations in resistant-related genes involved in resistance to fluoroquinolone (FLQ) and second-line injectable drugs. The broth microdilution method using 7H9 Middlebrook media supplemented with OADC was used to determine the MICs. The MTBDRsl VER 2.0 correctly detected 5/6 (83.3%) of FLQ-resistant strains. The MUT1 A1401G (seven strains) and MUT2 G1484T (one strain) mutations in rrs gene were detected in eight AMK/KAN/CAP-resistant strains. Four low-level KAN-resistant strains with the G-10A/C-12T (three strains) and eis C-14T (one strain) mutations in eis gene was diagnosed using MTBDRsl VER 2.0. Five errors were found in detecting resistance to kanamycin and capreomycin compared to the phenotypic drug susceptibility testing and WGS. Failling wild-type bands without improved mutant bands did not indicate a reliable resistance. WGS could efficiently resolve the discrepancies of the results. MTBDRsl showed better performance in detecting XDR strains than pre-XDR.

Topics: Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Fluoroquinolones; Genotype; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant; Whole Genome Sequencing

Studies have shown that drug-resistant tuberculosis (DR-TB) in South Africa (SA) is clonal and is caused mostly by transmission. Identifying transmission chains is important in controlling DR-TB. This study reports on the sentinel molecular surveillance data of Rifampicin-Resistant (RR) TB in SA, aiming to describe the RR-TB strain population and the estimated transmission of RR-TB cases.. RR-TB isolates collected between 2014 and 2018 from eight provinces were genotyped using combination of spoligotyping and 24-loci mycobacterial interspersed repetitive-units-variable-number tandem repeats (MIRU-VNTR) typing.. Of the 3007 isolates genotyped, 301 clusters were identified. Cluster size ranged between 2 and 270 cases. Most of the clusters (247/301; 82.0%) were small in size (< 5 cases), 12.0% (37/301) were medium sized (5-10 cases), 3.3% (10/301) were large (11-25 cases) and 2.3% (7/301) were very large with 26-270 cases. The Beijing genotype was responsible for majority of RR-TB cases in Western and Eastern Cape, while the East-African-Indian-Somalian (EAI1_SOM) genotype accounted for a third of RR-TB cases in Mpumalanga. The overall proportion of RR-TB cases estimated to be due to transmission was 42%, with the highest transmission-rate in Western Cape (64%) and the lowest in Northern Cape (9%).. Large clusters contribute to the burden of RR-TB in specific geographic areas such as Western Cape, Eastern Cape and Mpumalanga, highlighting the need for community-wide interventions. Most of the clusters identified in the study were small, suggesting close contact transmission events, emphasizing the importance of contact investigations and infection control as the primary interventions in SA.

Topics: Antitubercular Agents; Drug Resistance, Bacterial; Genotype; Humans; Mycobacterium tuberculosis; Polymerase Chain Reaction; Rifampin; South Africa; Tuberculosis, Multidrug-Resistant

in Cameroon patients with multidrug/rifampicin resistant pulmonary tuberculosis (MDR/RR-PTB) are treated with a 9-11 month standardised shorter treatment regimen. Despite its effectiveness, factors associated with the occurrence of an unfavourable treatment outcome in this group of patients are not known. Determine the incidence and identify factors associated with an unfavourable treatment outcome among patients with rifampicin resistant pulmonary tuberculosis (RR-PTB) in Yaoundé.. we conducted a retrospective record review of all consecutive patients with bacteriologically confirmed RR-PTB followed up at the specialised MDR/RR-TB treatment centre of the Jamot Hospital in Yaoundé (JHY) from January 2013 to November 2019. A patient was classified as having an unfavourable outcome if he/she had treatment failure, died or was lost to follow-up during the course of treatment.. a total of 242 RR-PTB patients with a mean age of 35.59 ± 12.02 years including 144 (59.5%) males were registered. Forty-nine (49) of the 242 patients had an unfavourable treatment outcome giving a cumulative incidence of 20.20% (95% confidence interval (95% CI): 15.40-25.90%). Multivariable analysis revealed that patients with an unfavourable outcome were more likely to be males (odds ratio (OR): 2.94; 95% CI: 1.24-7.00, p= 0.015), HIV infected (OR: 2.67; 95% CI: 1.17-6.06, p = 0.019), and have a baseline haemoglobin level ≤ 10g/dl (OR: 2.87; 95% CI: 1.25-6.58, p = 0.013).. the rate of an unfavourable treatment outcome among patients with RR-PTB at the specialised MDR/RR-TB treatment centre of the JHY is relatively high. The male sex, HIV infection and moderate to severe anaemia are independent factors associated with an unfavourable treatment outcome.

Topics: Adult; Anemia; Antitubercular Agents; Cameroon; Female; HIV Infections; Humans; Incidence; Male; Middle Aged; Retrospective Studies; Rifampin; Risk Factors; Sex Factors; Treatment Failure; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

On analyzing the drug susceptibility profile of 151 clinical isolates collected from patients of tuberculous meningitis (TBM) over 10 years, we reflect on few lessons learnt from the trend of susceptibility profile - drug resistance was not uncommon, fluoroquinolone resistance was observed even among otherwise susceptible isolates and hetero-resistance was observed against rifampicin, isoniazid and also fluoroquinolones. In the midst of widening gap between incidence of drug resistant TBM and availability of effective drugs, our data suggests that universal testing for drug resistance, careful choice of drugs having optimal penetration and individualized therapy should form important pillars of TBM management.

Topics: Antitubercular Agents; Fluoroquinolones; Humans; Isoniazid; Mycobacterium tuberculosis; Patient-Centered Care; Rifampin; Tuberculosis, Meningeal; Tuberculosis, Multidrug-Resistant

Treatment outcomes for Multidrug-Resistant Tuberculosis (MDR TB) is generally poor. The study aims to know about the treatment outcomes of MDR-TB under programmatic conditions in Hyderabad District and to analyze the factors influencing the treatment outcomes.. This is a retrospective study in which 377 patients of Hyderabad district, Telangana state who were diagnosed with MDR TB and registered at Drug Resistance TB Treatment site of Government General & Chest Hospital, Hyderabad from 4th quarter 2008 to 4th quarter 2013 were included in the study. Impact of Demographic factors (age, sex; Nutritional status (BMI); Co-morbid condition (Diabetes, HIV, Hypothyroidism); Programmatic factors (time delay in the initiation of treatment); Initial Resistance pattern on the outcomes were studied and analyzed.. The treatment outcomes of Multidrug-Resistant Tuberculosis under Programmatic Conditions were: 57% cured, 21.8% died, 19.6% defaulted, 1.1% failed and 0.5% switched to XDR. Age, Sex, BMI had a statistically significant impact on treatment outcomes. Hypothyroidism and Delay in the initiation of treatment >1 a month had an impact on the outcomes though not statistically significant. NO impact on treatment outcomes was found when Rifampicin resistance & INH sensitive patients were compared with those resistant to both INH and Rifampicin.. To reduce MDR-TB transmission in the community, improvement of treatment outcomes, via ensuring adherence, paying special attention to elderly patients is required. The Programmatic Management of Drug Resistance Tuberculosis (PMDT) should seriously think of providing Nutritional support to patients with low BMI to improve outcomes. In the programmatic conditions if we could address the problems like delay in initiation of treatment and proper management of comorbidities like HIV, Diabetes, Hypothyroidism would definitely improve the treatment outcomes.

Topics: Adult; Age Factors; Aged; Antibiotics, Antitubercular; Comorbidity; Female; Geriatric Assessment; Humans; India; Male; Mycobacterium tuberculosis; Nutritional Status; Rifampin; Risk Assessment; Risk Factors; Sex Factors; Time-to-Treatment; Treatment Adherence and Compliance; Tuberculosis, Multidrug-Resistant

Differences among Mycobacterium tuberculosis complex (MTC) species may predict drug resistance or treatment success. Thus, we optimised and deployed the genotype MTBC assay (gMTBC) to identify MTC to the species level, and then performed comparative genotypic drug-susceptibility testing to anti-tuberculosis drugs from direct sputum of patients with presumed multidrug-resistant tuberculosis (MDR-TB) by the MTBDRplus/sl reference method.. Among 73 patients, 53 (73%) were male and had a mean age of 43 (95% CI; 40-45) years. In total, 34 (47%), 36 (49%) and 38 (55%) had positive gMTBC, culture and MTBDR respectively. Forty patients (55%) had low quantity MTC by Xpert, including 31 (78%) with a negative culture. gMTBC was more likely to be positive in patients with chest cavity 4.18 (1.31-13.32, P = 0.016), high-quantity MTC by Xpert 3.03 (1.35-6.82, P = 0.007) and sputum smear positivity 1.93 (1.19-3.14, P = 0.008). The accuracy of gMTBC in detecting MTC was 95% (95% CI; 86-98; κ = 0.89) compared to MTBDRplus/sl. All M. tuberculosis/canettii identified by gMTB were susceptible to fluoroquinolone and aminoglycosides/capreomycin.. The concordance between the gMTBC assay and MTBDRplus/sl in detecting MTC was high but lagged behind the yield of Xpert MTB/RIF. All M. tuberculosis/canettii were susceptible to fluoroquinolones, a core drug in MDR-TB treatment regimens.

Topics: Adult; Antitubercular Agents; Bacterial Typing Techniques; Cross-Sectional Studies; Female; Fluoroquinolones; Genotype; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Rifampin; Species Specificity; Sputum; Tanzania; Tuberculosis, Multidrug-Resistant

In this study, we aimed to investigate the molecular epidemiology and drug-resistance profiles of tuberculosis (TB) in Luodian, an area with highest TB incidence and limited healthcare resources in Guizhou, China. The passive case finding strategy was used to identify suspected pulmonary TB with symptoms, and individuals with positive Mycobacterium tuberculosis (MTB) culture were enrolled from May 22, 2018 to April 21, 2019. All the 107 cases except three came from nine towns, including 55.1% from Longping and Bianyang. The phylogeny tree showed that 53.3% of strains were Lineage 2 (Beijing genotype), while 46.7% were Lineage 4 (Euro-American genotype). Among Lineage 2 strains, 66.7% were of "modern" Beijing type. Seven clusters with genomic distance within 12 SNPs were identified. The clusters included 14 strains, accounting for a clustering rate of 13.1%. The distance separating the clustered cases was between 2.1 and 71.0 km (Km), with an average paired distance of 21.8 Km (interquartile range, 2.8-38.0 Km). Based on the gene mutations associated with drug-resistance, we predicted that 4.8% of strains were resistant to isoniazid, 3.7% to rifampicin, and 3.7% to streptomycin; only one strain (0.9%) had multidrug resistance (MDR). This study found low drug-resistance rates in Luodian, and the sub-lineage of the "modern" Beijing branch has recent expansion in Luodian. This work may also serve as a genomic baseline to assess the evolution and spread of MTB in Guizhou.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Anti-Bacterial Agents; China; Drug Resistance, Bacterial; Female; Humans; Incidence; Isoniazid; Male; Middle Aged; Molecular Epidemiology; Phylogeny; Prevalence; Rifampin; Streptomycin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Whole Genome Sequencing; Young Adult

Topics: Antibiotics, Antitubercular; Drug Resistance, Bacterial; Humans; Mycobacterium tuberculosis; Rifampin; Time-to-Treatment; Tuberculosis, Multidrug-Resistant

Topics: Antibiotics, Antitubercular; Antitubercular Agents; Home Care Services; Humans; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Whole genome sequencing (WGS) analysis in tuberculosis allows the prediction of drug-resistant phenotypes, identification of lineages, and to better understanding of the epidemiology and transmission chains. Nevertheless the procedure has been scarcely assessed in Mexico, in this work we analyze by WGS isolates of Mycobacterium tuberculosis circulating in Jalisco, Mexico. Lineage and phylogenetic characterization, drug resistant prediction, "in silico" spoligotyping determination, were provided by WGS in 32 M. tuberculosis clinical isolates. Lineage 4 (L4), with 28 isolates (87%) and eleven sublineages was dominant. Forty SNPs and INDELs were found in genes related to first-, and second-line drugs. Eleven isolates were sensitive, seven (22%) were predicted to be resistant to isoniazid, two resistant to rifampicin (6%) and two (6%) were multidrug-resistant tuberuclosis. Spoligotyping shows that SIT 53 (19%) and SIT 119 (16%) were dominant. Four clonal transmission complexes were found. This is the first molecular epidemiological description of TB isolates circulating in western Mexico, achieved through WGS. L4 was dominant and included a high diversity of sublineages. It was possible to track the transmission route of two clonal complexes. The WGS demonstrated to be of great utility and with further implications for clinical and epidemiological study of TB in the region.

Topics: Adolescent; Adult; Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Female; Humans; Isoniazid; Male; Mexico; Microbial Sensitivity Tests; Middle Aged; Molecular Epidemiology; Mycobacterium tuberculosis; Phenotype; Phylogeny; Rifampin; Tuberculosis, Multidrug-Resistant; Whole Genome Sequencing; Young Adult

Clinical isolates of drug-resistant (isoniazid and/or rifampicin-resistant) Mycobacterium tuberculosis were obtained from 254 patients diagnosed with drug-resistant tuberculosis in Japan from April 2015 to March 2017 in National Hospital Organization hospitals. The 254 patients were approximately 32% of all 795 patients who were diagnosed with culture-confirmed drug-resistant tuberculosis from 2015 to 2016 nationwide in Japan. The whole-genome sequences of all the isolates from the 254 patients and the lineages of these isolates were determined, and phylogenetic trees were constructed based on single nucleotide polymorphism concatemers. Of these patients, 202 (79.5%) were born in Japan and 52 (20.5%) were born elsewhere. Of the 254 drug-resistant isolates, 54 (21.3%) were multidrug resistant, being resistant to both isoniazid and rifampicin. The percentages of multidrug-resistant isolates were significantly higher in foreign-born (38.5% [20/52]) than Japanese-born patients (16.8% [34/202]). Of the 54 multidrug-resistant isolates, nine were extensively drug resistant, which were all obtained from Japanese-born patients. Five extensively drug-resistant isolates were obtained from patients with incipient tuberculosis. A significant number of multidrug-resistant M. tuberculosis strains were isolated from foreign-born patients from Asian countries that have a high tuberculosis burden. Foreign-derived isolates affect the nationwide genetic diversity of drug-resistant M. tuberculosis in Japan. Extensively drug-resistant M. tuberculosis isolates were transmitted among the Japanese population.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antibiotics, Antitubercular; DNA, Bacterial; Drug Resistance, Multiple, Bacterial; Emigrants and Immigrants; Epidemiological Monitoring; Female; Genome, Bacterial; Humans; Japan; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Phylogeny; Rifampin; Tuberculosis, Multidrug-Resistant; Whole Genome Sequencing; Young Adult

Rifampicin (RIF) is one of the most effective anti-tuberculosis first-line drugs prescribed along with isoniazid. However, the emergence of RIF resistance Mycobacterium tuberculosis (MTB) isolates is a major issue towards tuberculosis (TB) control program in high MDR TB-burdened countries including Pakistan. Molecular data behind phenotypic resistance is essential for better management of RIF resistance which has been linked with mutations in rpoB gene. Since molecular studies on RIF resistance is limited in Pakistan, the current study was aimed to investigate the molecular data of mutations in rpoB gene behind phenotypic RIF resistance isolates in Pakistan.. A total of 322 phenotypically RIF-resistant isolates were randomly selected from National TB Reference Laboratory, Pakistan for sequencing while 380 RIF resistance whole-genome sequencing (WGS) of Pakistani isolates (BioProject PRJEB25972), were also analyzed for rpoB mutations.. Among the 702 RIF resistance samples, 675 (96.1%) isolates harbored mutations in rpoB in which 663 (94.4%) were detected within the Rifampicin Resistance Determining Region (RRDR) also known as a mutation hot spot region, including three novel. Among these mutations, 657 (97.3%) were substitutions including 603 (89.3%) single nucleotide polymorphism, 49 (7.25%) double and five (0.8%) triple. About 94.4% of Phenotypic RIF resistance strains, exhibited mutations in RRDR, which were also detectable by GeneXpert.. Mutations in the RRDR region of rpoB is a major mechanism of RIF resistance in MTB circulating isolates in Pakistan. Molecular detection of drug resistance is a faster and better approach than phenotypic drug susceptibility testing to reduce the time for transmission of RIF resistance strains in population. Such insights will inform the deployment of anti-TB drug regimens and disease control tools and strategies in high burden settings, such as Pakistan.

Topics: Antitubercular Agents; Bacterial Proteins; DNA-Directed RNA Polymerases; Humans; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Pakistan; Rifampin; Tuberculosis, Multidrug-Resistant

Tuberculosis (TB), caused by Mycobacterium tuberculosis, is endemic in Pakistan. Resistance to both firstline rifampicin and isoniazid drugs (multidrug-resistant TB; MDR-TB) is hampering disease control. Rifampicin resistance is attributed to rpoB gene mutations, but rpoA and rpoC loci may also be involved. To characterise underlying rifampicin resistance mutations in the TB endemic province of Khyber Pakhtunkhwa, we sequenced 51 M. tuberculosis isolates collected between 2016 and 2019; predominantly, MDR-TB (n = 44; 86.3%) and lineage 3 (n = 30, 58.8%) strains. We found that known mutations in rpoB (e.g. S405L), katG (e.g. S315T), or inhA promoter loci explain the MDR-TB. There were 24 unique mutations in rpoA, rpoB, and rpoC genes, including four previously unreported. Five instances of within-host resistance diversity were observed, where two were a mixture of MDR-TB strains containing mutations in rpoB, katG, and the inhA promoter region, as well as compensatory mutations in rpoC. Heteroresistance was observed in two isolates with a single lineage. Such complexity may reflect the high transmission nature of the Khyber Pakhtunkhwa setting. Our study reinforces the need to apply sequencing approaches to capture the full-extent of MDR-TB genetic diversity, to understand transmission, and to inform TB control activities in the highly endemic setting of Pakistan.

Topics: Antitubercular Agents; Bacterial Proteins; Catalase; DNA-Directed RNA Polymerases; Humans; Models, Molecular; Mutation; Mycobacterium tuberculosis; Oxidoreductases; Pakistan; Phylogeny; Rifampin; Tuberculosis, Multidrug-Resistant

The very high burden of rifampicin resistance tuberculosis (RR-TB) and the very low detection of RR-TB cases are a major challenge that China has been facing. This study analyzed the characteristics of RR-TB detection in China after the change of RR-TB detection strategy since 2015, aiming to provide reference and evidence for the development of more precise national drug resistance tuberculosis prevention and control policy.. We extracted data related to rifampicin resistance screening from the national Tuberculosis Information Management System (TBIMS) from 2015 to 2019, and used descriptive research methods to analyze the screening rate of presumptive RR-TB, the number and duration of RR-TB patients detected and drug resistance testing methods in each year. Chi-square test was used to compare the differences in component ratio or rate between years, and Kruskal Wallis test was used to compare the differences in median days for detection of RR-TB patients in each year.. A total of 68,200 RR-TB cases were detected during 2015-2019, of which 48.1% were new cases. The number and detection rate of RR-TB cases increased year by year, from 10 019 and 14.3% in 2015 to 18 623 and 28.7% in 2019, respectively. Of the bacteriologically confirmed TB cases, 81.9% were tested for RR in 2019, a considerable increase from 29.5% in 2015. In 2019, only 41.0% of RR-TB cases had fluoroquinolones (FQs) susceptibility testing performed, and this proportion has been declining year by year since 2016. The proportion of application of rapid molecular tools increased from 24.0% in 2015 to 67.1% in 2019, and the median days to obtain RR results was significantly shortened. In 2019, 76.0% of RR-TB cases were diagnosed as presumptive RR-TB in county-level hospitals.. After China modified the RR-TB detection strategy, the screening rate of RR and the number of RR-TB cases increased significantly. The RR testing methods now predominantly utilize rapid molecular tools. However, comprehensive measures should be implemented to close the gap in the detection of RR-TB cases. It is imperative to take FQs susceptibility testing seriously and effectively strengthen the laboratory capacity of county-level hospitals.

Topics: China; Humans; Mass Screening; Mycobacterium tuberculosis; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Genomic-based surveillance on the occurrence of drug resistance and its transmission dynamics has emerged as a powerful tool for the control of tuberculosis (TB). A whole-genome sequencing approach, phenotypic testing and clinical-epidemiological investigation were used to undertake a retrospective population-based study on drug-resistant (DR)-TB in Rio Grande do Sul, the largest state in Southern Brazil. The analysis included 305 resistant Mycobacterium tuberculosis strains sampled statewide from 2011 to 2014, and covered 75.7% of all DR-TB cases identified in this period. Lineage 4 was found to be predominant (99.3%), with high sublineage-level diversity composed mainly of 4.3.4.2 [Latin American and Mediterranean (LAM)/RD174], 4.3.3 (LAM/RD115) and 4.1.2.1 (Haarlem/RD182) sublineages. Genomic diversity was also reflected in resistance of the variants to first-line drugs. A large number of distinct resistance-conferring mutations, including variants that have not been reported previously in any other setting worldwide, and 22 isoniazid-monoresistant strains with mutations described as disputed in the rpoB gene but causing rifampicin resistance generally missed by automated phenotypic tests as BACTEC MGIT. Using a cut-off of five single nucleotide polymorphisms, the estimated recent transmission rate was 55.1%, with 168 strains grouped into 28 genomic clusters. The most worrying fact concerns multi-drug-resistant (MDR) strains, of which 73.4% were clustered. Different resistance profiles and acquisition of novel mutations intraclusters revealed important amplification of resistance in the region. This study described the diversity of M. tuberculosis strains, the basis of drug resistance, and ongoing transmission dynamics across the largest state in Southern Brazil, stressing the urgent need for MDR-TB transmission control state-wide.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antibiotics, Antitubercular; Antitubercular Agents; Bacterial Proteins; Brazil; DNA-Directed RNA Polymerases; Drug Resistance, Multiple, Bacterial; Gene Expression Profiling; Genome, Bacterial; Humans; Isoniazid; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Polymorphism, Single Nucleotide; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant; Whole Genome Sequencing; Young Adult

Detection of tuberculosis disease (TB) and timely identification of Mycobacterium tuberculosis (Mtb) strains that are resistant to treatment are key to halting tuberculosis transmission, improving treatment outcomes, and reducing mortality.. We used 332,657 Xpert MTB/RIF assay results, captured as part of the Myanmar Data Utilization Project, to characterize Mtb test positivity and rifampicin resistance by both age and sex, and to evaluate risk factors associated with rifampicin resistance.. Overall, 70% of individuals diagnosed with TB were males. Test positivity was higher among males (47%) compared to females (39%). The highest positivity by age occurred among individuals aged 16-20, with test positivity for females (65%) higher than for males (57%). Although a greater absolute number of males were rifampicin resistant, a greater proportion of females (11.4%) were rifampicin resistant as compared to males (9.3%). In the multivariate model, history of previous treatment, age less than 30, testing in the Yangon region, and female sex were significantly positively associated with rifampicin resistance after adjusting for HIV status and year test was performed.. Our results indicate that young adults were more likely to test positive for TB and be identified as rifampicin resistant compared to older adults.

Topics: Aged; Antibiotics, Antitubercular; Drug Resistance, Bacterial; Female; Humans; Male; Myanmar; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Sex Distribution; Tuberculosis; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

Simple, rapid, and accurate detection of the Mycobacterium tuberculosis complex (MTBC) and drug resistance is critical for improving patient care and decreasing the spread of tuberculosis. To this end, we have developed a new simple and rapid molecular method, which combines multienzyme isothermal rapid amplification and a lateral flow strip, to detect MTBC and simultaneously detect rifampin (RIF) resistance. Our findings showed that it has sufficient sensitivity and specificity for discriminating 118 MTBC strains from 51 non-tuberculosis mycobacteria strains and 11 of the most common respiratory tract bacteria. Further, compared to drug susceptibility testing, the assay has a sensitivity, specificity, and accuracy of 54.1%, 100.0%, and 75.2%, respectively, for detection of RIF resistance. Some of the advantages of this assay are that no special instrumentation is required, a constant low temperature of 39 °C is sufficient for the reaction, the turnaround time is less than 20 min from the start of the reaction to read out and the result can be seen with the naked eye and does not require specialized training. These characteristics of the new assay make it particularly useful for detecting MTBC and RIF resistance in resource-limited settings.

Topics: Antibiotics, Antitubercular; Bacterial Proteins; DNA-Directed RNA Polymerases; DNA, Protozoan; Enzyme-Linked Immunosorbent Assay; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Point Mutation; Polymerase Chain Reaction; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

Tuberculosis is a communicable disease with high morbidity and mortality rates in developing countries. The study's primary objective is to compare conventional methods such as acid-fast bacillus (AFB) culture and microscopy with rapid diagnostic methods. The secondary objective is to compare histopathological and microbiological findings in suspected patients with tubercular lymphadenitis. A total of 111 samples (August 2018 to September 2019) of lymph nodes were processed for AFB microscopy, AFB cultures, drug-susceptibility testing (DST), histopathology, and Xpert Mycobacterium Tuberculosis (MTB)/resistance to Rifampin (RIF) assays. Out of 111 lymph node samples, 6 (5.4%) were positive for AFB smear microscopy, 84 (75.6%) were positive for AFB culture, 80 (70.7%) were positive on Gene Xpert, and 102 (91.8%) were indicative of tuberculosis for histopathology studies. Mycobacteria growth indicator tube (MGIT) culture positivity was 84 (75.6%) higher than solid Lowenstein-Jensen (LJ) culture 74 (66.6%). Positive cultures underwent phenotypic DST. Two cases were Multidrug-resistant (MDR) on DST, while three cases were Rifampicin resistant on Gene Xpert. The sensitivity of Genexpert was (62%) against the conventional AFB culture method. The poor performance of conventional lymphadenitis diagnostic methods requires early and accurate diagnostic methodology. Xpert MTB/RIF test can help in the treatment of multidrug-resistant TB cases. Nonetheless, rapid and conventional methods should be used for complete isolation of Mycobacterium tuberculosis.

Topics: Humans; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Lymph Node; Tuberculosis, Multidrug-Resistant

A series of 4H-chromen-4-one derivatives obtained by scaffold morphing of the benzofuran compound, TAM16, were tested for antitubercular activity. Compound 8d was active against drug-sensitive and multidrug-resistant tuberculosis. A preliminary druggability evaluation showed that compound 8d displayed favorable mouse and human microsomal stability, low cytotoxicity, and acceptable oral bioavailability. An in vivo study indicated that compound 8d exhibited modest efficacy in an acute mouse model of TB after 3 weeks of treatment. Thus, 8d is a promising antituberculosis lead compound.

Topics: Animals; Antitubercular Agents; Benzofurans; Benzopyrans; Drug Design; Humans; Mice; Mice, Inbred BALB C; Microbial Sensitivity Tests; Microsomes, Liver; Molecular Structure; Mycobacterium tuberculosis; Structure-Activity Relationship; Tuberculosis, Multidrug-Resistant

A series of new benzothiazinone derivatives containing a symmetric 2-benzyl-2,7-diazaspiro[3.5]nonane moiety, based on the structure of LK02 discovered in our lab, were designed and synthesized. With one exception 3, all of them show excellent in vitro activity against both drug-sensitive and clinically isolated multidrug-resistant Mycobacterium tuberculosis (MTB) strains (MIC: < 0.016 μg/mL). Compound 2d with a methyl group at the benzylic carbon, was identified to have good safety and significant efficacy in an acute mouse model of TB, as well as better PK profiles than PBTZ169.

Topics: Alkanes; Animals; Antitubercular Agents; Drug Design; Drug Resistance; Mice; Mycobacterium tuberculosis; Structure-Activity Relationship; Thiazines; Tuberculosis, Multidrug-Resistant

Tuberculosis (TB) remains a serious public health challenge, and the research and development of new anti-TB drugs is an essential component of the global strategy to eradicate TB. In this work, we discovered a conformationally constrained oxazolidinone

Topics: Animals; Chlorocebus aethiops; Drug Design; Female; Hep G2 Cells; Humans; Mice; Microbial Sensitivity Tests; Molecular Conformation; Mycobacterium tuberculosis; Oxazolidinones; Safety; Tuberculosis, Multidrug-Resistant; Vero Cells

The Xpert MTB/RIF (Xpert) assay has greatly improved the diagnosis of TB and identification of resistance to rifampicin (RIF). However, sensitivity of Xpert remains poor for pleural fluid detection. This study evaluated the performance of the novel next-generation Xpert MTB/RIF Ultra (Xpert Ultra) in comparison with Xpert for pleural TB diagnosis.. Patients with suspected pleural TB were enrolled consecutively in four hospitals, and pleural fluids were subjected to smear, culture, and Xpert. Defrosted pleural fluid (-80°C) was examined using Xpert Ultra. Drug susceptibility testing (DST) was conducted for all of the recovered isolates.. In total, 317 individuals with suspected pleural TB were recruited; 208 of them were diagnosed with pleural TB according to the composite reference standard, which was composed of clinical, laboratory, histopathologic, and radiologic examination features and ≥ 12 months of follow-up data. The direct head-to-head comparison for Mycobacterium tuberculosis detection showed that Xpert Ultra (44.23%, 92 of 208) produced a higher sensitivity than culture (26.44%, 55 of 208, P < .001), Xpert (19.23%, 40 of 208, P < .001), and smear (1.44%, three of 208, P < .001). When Xpert Ultra outcomes were integrated, the percentage of definite pleural TB cases increased from 56.25% (117 of 208) to 64.90% (135 of 208). The specificities of smear, culture, Xpert, and Xpert Ultra were 100% (84 of 84), 100% (84 of 84), 98.67% (83 of 84), and 98.67% (83 of 84), respectively. Xpert Ultra was 100% concordant with phenotype DST for the detection of RIF resistance.. Xpert Ultra has great potential in diagnosis of pleural TB and its RIF resistance, which could speed up the initiation of appropriate treatment.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antibiotics, Antitubercular; Culture Techniques; Drug Resistance, Microbial; Female; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Pleural Effusion; Polymerase Chain Reaction; Predictive Value of Tests; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pleural; Young Adult

A cross-sectional observational study.. This study aims to determine the diagnostic accuracy, sensitivity, and specificity of the Xpert MTB/RIF assay (Mycobacterium Tuberculosis/Rifampicin resistance) for the detection of spinal Tuberculosis (TB) and rifampicin (RIF) resistance.. The Spinal TB is often a paucibacillary extra pulmonary tuberculosis which gives a major challenge in early diagnosis and initializing the correct anti-tubercular treatment (ATT). Due to its rapidity and sensitivity, the dependence and reliability on the Xpert MTB/RIF assay has increased in the last few years. The studies describing accuracy of the Xpert MTB/RIF assay in spinal TB are scanty.. This institutional review board-approved study included 360 diagnosed spinal TB patients. To determine the accuracy of the Xpert MTB/RIF assay, it was compared with other diagnostic tests like histopathology, acid fast bacilli (AFB) smear, culture, and drug sensitivity testing (DST).. The Xpert MTB/RIF assay showed 86.3% sensitivity and 85.3% specificity when compared with culture for the diagnosis of Spinal TB and showed 75.86% sensitivity, 96.12% specificity for RIF resistance when compared to DST. Four cases were false positive and 11 cases were false negative for RIF resistance on the Xpert MTB/RIF assay.. The Xpert MTB/RIF assay is an efficient technique for the rapid diagnosis of spinal TB; however, a clinician should not solely rely on it for starting ATT. As there are false results also with this test which should be read cautiously and be well correlated with culture and DST pattern to guide the start of sensitive drug regimen only. The purpose is to prevent exposure of the second line drugs to false cases found on the Xpert MTB/RIF assay and avoid emergence of new acquired drug resistance.. 4.

Topics: Antibiotics, Antitubercular; Cross-Sectional Studies; Humans; Molecular Typing; Reproducibility of Results; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant; Tuberculosis, Spinal

Tuberculosis (TB) control is hindered by absence of rapid tests to identify Mycobacterium tuberculosis (MTB) and detect isoniazid (INH) and rifampin (RIF) resistance. We evaluated the accuracy of the BD MAX multidrug-resistant (MDR)-TB assay (BD MAX) in South Africa, Uganda, India, and Peru.. Outpatient adults with signs/symptoms of pulmonary TB were prospectively enrolled. Sputum smear microscopy and BD MAX were performed on a single raw sputum, which was then processed for culture and phenotypic drug susceptibility testing (DST), BD MAX, and Xpert MTB/RIF (Xpert).. 1053 participants with presumptive TB were enrolled (47% female; 32% with human immunodeficiency virus). In patients with confirmed TB, BD MAX sensitivity was 93% (262/282 [95% CI, 89-95%]); specificity was 97% (593/610 [96-98%]) among participants with negative cultures on raw sputa. BD MAX sensitivity was 100% (175/175 [98-100%]) for smear-positive samples (fluorescence microscopy), and 81% (87/107 [73-88%]) in smear-negative samples. Among participants with both BD MAX and Xpert, sensitivity was 91% (249/274 [87-94%]) for BD MAX and 90% (246/274 [86-93%]) for Xpert on processed sputa. Sensitivity and specificity for RIF resistance compared with phenotypic DST were 90% (9/10 [60-98%]) and 95% (211/222 [91-97%]), respectively. Sensitivity and specificity for detection of INH resistance were 82% (22/27 [63-92%]) and 100% (205/205 [98-100%]), respectively.. The BD MAX MDR-TB assay had high sensitivity and specificity for detection of MTB and RIF and INH drug resistance and may be an important tool for rapid detection of TB and MDR-TB globally.

Topics: Adult; Drug Resistance, Bacterial; Female; Humans; India; Isoniazid; Male; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Peru; Rifampin; Sensitivity and Specificity; South Africa; Sputum; Tuberculosis, Multidrug-Resistant; Uganda

Numerous investigations demonstrate efflux as a worldwide bacterial mode of action which contributes to the resistance of drugs. The activity of antibiotics, which subjects to efflux, can be improved by the combined usage of efflux inhibitors. However, the efflux role to the overall levels of antibiotic resistance of clinical M. tuberculosis isolates is inadequately comprehended and is still disregarded by many.. Here, we assessed the contribution of resistant genes associated with isoniazid (INH) and rifampin (R) resistance to the levels of drug resistance in the (27) clinical isolates of MDR-TB. Additionally, the role of the resistance for six putative drug efflux pump genes to the antibiotics was investigated. The level of katG expression was down-regulated in 24/27 (88.88%) of MDR-TB isolates. Of the 27 MDR-TB isolates, inhA, oxyR-ahpC, and rpoB showed either overexpression or up-regulation in 8 (29.62%), 4 (14.81 %), and 24 (88.88%), respectively. Moreover, the efflux pump genes drrA, drrB, efpA, Rv2459, Rv1634, and Rv1250 were overexpressed under INH/RIF plus fresh pomegranate juice (FPJ) stress signifying the efflux pumps contribution to the overall levels of the resistance of MDR-TB isolates.. These results displayed that the levels of drug resistance of MDR-TB clinical isolates are due to combination among drug efflux pump and the presence of mutations in target genes, a truth which is often ignored by the specialists of tuberculosis in favour of the almost undoubted significance of drug target- gene mutations for the resistance in M. tuberculosis.

Topics: Antitubercular Agents; Gene Expression Regulation; Humans; Isoniazid; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Appropriate technology tests are needed for Mycobacterium tuberculosis drug-susceptibility testing (DST) in resource-constrained settings. This study was performed to evaluate the MDR/XDR-TB Colour Test (a colour platethin-layer agar test; TB-CX) for M. tuberculosis DST by directly testing sputum at University of Gondar Hospital.. Sputum samples were each divided into two aliquots. One aliquot was mixed with disinfectant and applied directly to the TB-CX quadrant petri-plate containing culture medium with and without isoniazid, rifampicin, or ciprofloxacin. Concurrently, the other aliquot was decontaminated with sodium hydroxide, centrifuged, and cultured on Lӧwenstein-Jensen medium; the stored M. tuberculosis isolates were then sub-cultured in BACTEC Mycobacteria Growth Indicator Tube (MGIT) 960 for reference DST.. The TB-CX test yielded DST results for 94% (123/131) of positive samples. For paired DST results, the median number of days from sputum processing to DST was 12 for TB-CX versus 35 for LJ-MGIT (p<0.001). Compared with LJ-MGIT for isoniazid, rifampicin, and multidrug-resistant tuberculosis, TB-CX had 59%, 96%, and 95% sensitivity; 96%, 94%, and 98% specificity; and 85%, 94%, and 98% agreement, respectively. All ciprofloxacin DST results were susceptible by both methods.. The TB-CX test was simple and rapid for M. tuberculosis DST. Discordant DST results may have resulted from sub-optimal storage and different isoniazid concentrations used in TB-CX versus the reference standard test.

Topics: Adolescent; Adult; Antitubercular Agents; Ciprofloxacin; Culture Media; Ethiopia; Extensively Drug-Resistant Tuberculosis; Female; Health Resources; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant; Young Adult

Multidrug-resistant tuberculosis (MDR-TB) is a global public health priority. The advent of the World Health Organisation's Short Course regimen for MDR-TB, which halves treatment duration, has transformed outcomes and treatment acceptability for affected patients. Bedaquiline, a cornerstone of the Short Course regimen, has unknown teratogenicity and the WHO therefore recommends reliable contraception for all female MDR-TB patients in order to secure eligibility for bedaquiline. We were concerned that low contraceptive uptake among female patients in our rural South African MDR-TB treatment programme could jeopardise their access to bedaquiline. We therefore conducted a service delivery improvement project that aimed to audit contraceptive use in female MDR-TB patients, integrate family planning services into MDR-TB care, and increase the proportion of female patients eligible for bedaquiline therapy.. Contraceptive use and pregnancy rates were audited in all female patients aged 13-50 years initiated on our MDR-TB treatment programme in 2016. We then implemented an intervention consisting of procurement of depot-medroxyprogesterone acetate (DMPA) for the MDR-TB unit and training of specialist MDR-TB nurses in administration of DMPA. The audit cycle was repeated for all female patients aged 13-50 years initiated on the programme in January-October 2017 (post-intervention).. The proportion of women on injectable contraceptives by the time of MDR-TB treatment initiation increased significantly in the post-intervention cohort (77.4% vs 23.9%, p<0.0001).. By integrating contraceptive services into our MDR-TB programme we significantly increased contraceptive uptake, protecting women from the obstetric risks associated with pregnancy during MDR-TB treatment and maximising their eligibility for bedaquiline therapy.

Topics: Adolescent; Adult; Antitubercular Agents; Contraception; Family Planning Services; Female; Health Services Accessibility; Humans; Isoniazid; Middle Aged; Pregnancy; Pregnancy Rate; Rifampin; Rural Population; South Africa; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant

Pyrazinamide still may be a useful drug for treatment of rifampin-resistant (RR-TB) or multidrug-resistant tuberculosis (MDR-TB) in China while awaiting scale up of new drugs and regimens including bedaquiline and linezolid. The level of pyrazinamide resistance among MDR-TB patients in China is not well established. Therefore, we assessed pyrazinamide resistance in a representative sample and explored determinants and patterns of pncA mutations.. MDR-TB isolates from the 2007 national drug resistance survey of China were sub-cultured and examined for pyrazinamide susceptibility by BACTEC MGIT 960 method. pncA mutations were identified by sequencing. Characteristics associated with pyrazinamide resistance were analyzed using univariable and multivariable log-binominal regression.. Of 401 MDR-TB isolates, 324 were successfully sub-cultured and underwent drug susceptibility testing. Pyrazinamide resistance was prevalent in 40.7% of samples, similarly among new and previously treated MDR-TB patients. Pyrazinamide resistance in MDR-TB patients was associated with lower age (adjusted OR 0.54; 95% CI, 0.34-0.87 for those aged ≧60 years compared to < 40 years). Pyrazinamide resistance was not associated with gender, residential area, previous treatment history and Beijing genotype. Of 132 patients with pyrazinamide resistant MDR-TB, 97 (73.5%) had a mutation in the pncA gene; with 61 different point mutations causing amino acid change, and 11 frameshifts in the pncA gene. The mutations were scattered throughout the whole pncA gene and no hot spot region was identified.. Pyrazinamide resistance among MDR-TB patients in China is common, although less so in elderly patients. Therefore, pyrazinamide should only be used for treatment of RR/MDR-TB in China if susceptibility is confirmed. Molecular testing for detection of pyrazinamide resistance only based on pncA mutations has certain value for the rapid detection of pyrazinamide resistance in MDR-TB strains but other gene mutations conferring to pyrazinamide resistance still need to be explored to increase its predictive ability .

Topics: Adult; Age Factors; Amidohydrolases; Antitubercular Agents; Base Sequence; China; Diarylquinolines; Genes, Bacterial; Genotype; Humans; Linezolid; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Point Mutation; Polymorphism, Single Nucleotide; Prevalence; Pyrazinamide; Rifampin; Risk Factors; Tuberculosis, Multidrug-Resistant

International policy for treatment of multidrug- and rifampin-resistant tuberculosis (MDR/RR TB) relies largely on individual patient data (IPD) from observational studies of patients treated under routine conditions. We prepared guidance on which data to collect and what measures could improve consistency and utility for future evidence-based recommendations. We highlight critical stages in data collection at which improvements to uniformity, accuracy, and completeness could add value to IPD quality. Through a repetitive development process, we suggest essential patient- and treatment-related characteristics that should be collected by prospective contributors of observational IPD in MDR/RR TB.

Topics: Antitubercular Agents; Humans; Mycobacterium tuberculosis; Observational Studies as Topic; Quality Improvement; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

The aim of this study was to characterize rpoC gene mutations in Mycobacterium tuberculosis (MTB) and investigate the factors associated with rpoC mutations and the relation between rpoC mutations and tuberculosis (TB) transmission. A total of 245 MTB clinical isolates from patients with TB in six provinces and two municipalities in China were characterized based on gene mutations through DNA sequencing of rpoC and rpoB genes, phenotyping via standard drug susceptibility testing, and genotypic profiling by mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR) typing. Approximately 36.4% of the rifampin-resistant isolates harbored nonsynonymous mutations in the rpoC gene. Twenty-nine nonsynonymous single mutations and three double mutations were identified. The rpoC mutations at locus 483 (11.3%) were predominant, and the mutations at V483G, W484G, I491V, L516P, L566R, N698K, and A788E accounted for 54.5% of the total detected mutations. Fifteen new mutations in the rpoC gene were identified. Rifampin resistance and rpoB mutations at locus 531 were significantly associated with rpoC mutations. MIRU-VNTR genotype results indicated that 18.4% of the studied isolates were clustered, and the rpoC mutations were not significantly associated with MIRU-VNTR clusters. A large proportion of rpoC mutation was observed in the rifampicin-resistant MTB isolates. However, the findings of this study do not support the association of rpoC mutation with compensated transmissibility.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Anti-Bacterial Agents; Bacterial Proteins; China; DNA-Directed RNA Polymerases; Drug Resistance, Multiple, Bacterial; Female; Genotype; Humans; Logistic Models; Male; Microbial Sensitivity Tests; Middle Aged; Minisatellite Repeats; Mutation; Mycobacterium tuberculosis; Polymerase Chain Reaction; Rifampin; Sequence Analysis, DNA; Tuberculosis; Tuberculosis, Multidrug-Resistant; Young Adult

Patient-centered care is pillar 1 of the "End TB" strategy, but little has been documented in the literature about what this means for people living with rifampicin-resistant (RR-TB). Optimizing care for such individuals requires a better understanding of the challenges they face and the support they need.. A qualitative study was done among persons living with RR-TB and members of their support network. A purposive sample was selected from a larger study population and open-ended interviews were conducted using a semi-standard interview guide. Interviews were recorded and transcribed and the content analyzed using an iterative thematic analysis based in grounded theory.. 16 participants were interviewed from three different provinces. Four distinct periods in which support was needed were identified: 1) pre-diagnosis; 2) pre-treatment; 3) treatment; and 4) post-treatment. Challenges common in all four periods included: socioeconomic issues, centralized care, and the need for better counseling at multiple levels.. Beyond being a "very humiliating illness", RR-TB robs people of their physical, social, economic, psychological, and emotional well-being far beyond the period when treatment is being administered. Efforts to tackle these issues are as important as new drugs and diagnostics in the fight against TB.

Topics: Adult; Attitude to Health; Female; Humans; Male; Middle Aged; Patient-Centered Care; Qualitative Research; Rifampin; South Africa; Tuberculosis, Multidrug-Resistant; Young Adult

Tuberculosis (TB) caused by resistant strains is becoming a public health concern also in high-income countries. In Pavia province, Northern Italy, the prevalence of foreign-born has increased in recent years. Nevertheless, it is unclear if this has modified epidemiology and resistance patterns of Mycobacterium tuberculosis. We retrospectively collected data on all the Mycobacterium tuberculosis strains isolated by culture in the microbiology reference laboratory of the province of Pavia from 01/01/1998 to 31/12/2017. Overall, 919 patients were identified, 320 were foreign-born (34.8%). The proportion of cases due to foreign-born patients increased during the study period as did resistance to isoniazid (INH) (p = 0.01), while resistance to rifampicin (RIF) did not (p = 0.8). INH and RIF resistance were comparable among Italian and foreign-born patients (7.9% vs 9.7% for INH and 4% vs 5% for RIF, respectively). Twenty-height (3.05%) patients harboured MDR strains. Prevalence of MDR strains was not different between Italians and foreign-born patients (2.8% vs 3.4%, p = 0.6). During the study period the proportion of TB cases due to foreign-born patients and INH resistance increased. This increase was equal among Italian and foreign-born patients. Migrants in our area are not a driver of resistance to anti-mycobacterial drugs.

Topics: Adult; Aged; Antitubercular Agents; Female; Humans; Isoniazid; Italy; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Prevalence; Retrospective Studies; Rifampin; Transients and Migrants; Tuberculosis; Tuberculosis, Multidrug-Resistant

Topics: Adult; Aminoglycosides; Antitubercular Agents; Ethambutol; Female; Fluoroquinolones; Genotype; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Phenotype; Rifampin; Tuberculosis, Multidrug-Resistant; Turkey

Rapid and correct determination of Mycobacterium tuberculosis (MTB) drug susceptibility is a challenge for tuberculosis (TB) management. Phenotypic drug susceptibility testing (DST) remains the reference method but is time consuming. In this study, genotypic prediction of the first-line drug susceptibility profile obtained by whole-genome sequencing (WGS) was compared with that obtained by phenotypic DST and the line probe assay (LPA). All MTB strains isolated from patients during routine practice at the mycobacteria laboratory of Lyon University Hospital, France, between November 2016 and July 2019 were included (n = 274). Isolates were tested for the first-line drugs using phenotypic DST (Mycobacteria Growth Indicator Tube) and for genotypic prediction of the susceptibility profile with LPA and WGS. Considering phenotypic DST as the reference, WGS predicted resistance to rifampicin, isoniazid, ethambutol and pyrazinamide with sensitivities of 100%, 100%, 100% and 93.8%, respectively, and susceptibility to these drugs with specificities of 99.6%, 100%, 98.5% and 100%, respectively. Performance of the LPA was poorer, with sensitivity of 83.3% for rifampicin and 85.7% for isoniazid resistance. Five isolates were classified as susceptible according to phenotypic DST (1 for rifampicin, 4 for ethambutol) while WGS detected resistance mutations in rpoB and embB genes. WGS, used under appropriate quality-control conditions, has good performance to predict the resistance profile for the four first-line drugs and can correct phenotypic DST results. This study highlights the need for future guidelines recommending WGS as the initial tool in routine practice in areas where the prevalences of TB and drug-resistant MTB are low.

Topics: Antitubercular Agents; Bacterial Proteins; DNA-Directed RNA Polymerases; Drug Resistance, Multiple, Bacterial; Ethambutol; France; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Pentosyltransferases; Pyrazinamide; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Whole Genome Sequencing

Mutations in the genes inhA, katG, and rpoB confer resistance to anti-tuberculosis (TB) drugs isoniazid and rifampin. We questioned whether specific mutations in these genes were associated with different clinical and microbiological characteristics.. In a multicountry prospective cohort study of multidrug-resistant TB, we identified inhA, katG, and rpoB mutations in sputum isolates using the Hain MTBDRplus line probe assay. For specific mutations, we performed bivariate analysis to determine relative risk of baseline or acquired resistance to other TB drugs. We compared time to sputum culture conversion (TSCC) using Kaplan-Meier curves and stratified Cox regression.. In total, 447 participants enrolled from January 2005 to December 2008 from 7 countries were included. Relative to rpoB S531L, isolates with rpoB D516V had less cross-resistance to rifabutin, increased baseline resistance to other drugs, and increased acquired fluoroquinolone resistance. Relative to mutation of katG only, mutation of inhA promoter and katG was associated with baseline extensively drug resistant (XDR) TB, increased acquired fluoroquinolone resistance, and slower TSCC (125.5 vs 89.0 days).. Specific mutations in inhA and katG are associated with differences in resistance to other drugs and TSCC. Molecular testing may make it possible to tailor treatment and assess additional drug resistance risk according to specific mutation profile.

Topics: Antitubercular Agents; Bacterial Proteins; Catalase; DNA Mutational Analysis; DNA-Directed RNA Polymerases; DNA, Bacterial; Drug Resistance, Multiple, Bacterial; Genes, Bacterial; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Oxidoreductases; Promoter Regions, Genetic; Prospective Studies; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant

Molecular assays are endorsed for detection and confirmation of rifampicin-resistant TB. The frequency, causal mechanisms and impact of discordant results between molecular tests are not well understood.. The prevalence of discordant results was determined by pairwise comparison of molecular test results in a cohort of 749 rifampicin-resistant TB patients in three South African provinces. Culture isolates were sent to a research laboratory for WGS and rifampicin MIC determination. Clinical information was collected through medical file review.. The prevalence of discordances between Xpert MTB/RIF and MTBDRplus was 14.5% (95% CI 10.9%-18.9%), 5.6% (95% CI 2.2%-13.4%) between two consecutive Xpert assays and 4.2% (95% CI 2.2%-7.8%) between two consecutive MTBDRplus assays. Likely mechanisms of discordances were false rifampicin susceptibility on MTBDRplus (due to variants not included in mutant probes or heteroresistance with loss of minor variants in culture), false resistance on molecular assay in rifampicin-susceptible isolates, and human error. The healthcare worker changed the treatment regimen in 33% of patients with discordant results and requested 232 additional molecular tests after a first confirmatory test was performed in 460 patients. A follow-up Xpert assay would give the healthcare worker the 'true' rifampicin-resistant TB diagnosis in at least 73% of discordant cases.. The high rate of discordant results between Xpert and MTBDRplus has important implications for the laboratory, clinician and patient. While root causes for discordant result are multiple, a follow-up Xpert assay could guide healthcare workers to the correct treatment in most patients.

Topics: Antibiotics, Antitubercular; Drug Resistance, Bacterial; Humans; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

The Lesotho guidelines for the management of drug-resistant tuberculosis (TB) recommend initiation of patients diagnosed with rifampicin resistant (RR)-TB on a standardized drug resistant regimen while awaiting confirmation of rifampicin resistant TB (RR-TB) and complete drug susceptibility test results. Review of diagnostic records between 2014 and 2016 identified 518 patients with RR-TB. Only 314 (60.6%) patients could be linked to treatment records at the Lesotho MDR hospital. The median delay in treatment initiation from the availability of Xpert MTB/RIF assay result was 12 days (IQR 7-19). Only 32% (101) of patients had a documented first-line drug resistant test. MDR-TB was detected in 56.4% of patients while 33.7% of patients had rifampicin mono-resistance. Only 7.4% of patients assessed for second-line resistance had a positive result (resistance to fluoroquinolone). Treatment success was 69.8%, death rate was 28.8%, loss to follow up was 1.0%, and 0.4% failed treatment. Death was associated with positive or unavailable sputum smear at the end of first month of treatment (Fisher exact p < 0.001) and older age (p = 0.007). Urgent attention needs to be given to link patients with RR-TB to care worldwide. The association of death rate with positive sputum smear at the end of the first month of treatment should trigger early individualization of treatment.

Topics: Adolescent; Adult; Antibiotics, Antitubercular; Drug Resistance, Bacterial; Female; Fluoroquinolones; Follow-Up Studies; Humans; Lesotho; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Practice Guidelines as Topic; Retrospective Studies; Rifampin; Sputum; Time-to-Treatment; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

In Niger, the Shorter Treatment Regimen (STR) has been implemented nationwide for rifampicin resistant tuberculosis (RR-TB), since 2008. No previous publication has shown the results from countrywide programmatic implementation using few exclusion criteria, nor exhaustively assessed the effect of initial resistance to companion drugs on outcomes.. The National Tuberculosis Programme and the Damien Foundation conducted a retrospective observational study to evaluate the management of RR-TB from 2008 to 2016. Baseline resistance to drugs was assessed phenotypically, complemented by screening the inhA, katG and pncA genes. Cured patients were followed-up for a period of one year after cure.. Among 1044 patients tested for rifampicin resistance, mainly previously treated patients, 332 were diagnosed with pulmonary RR/TB, 288 were enrolled on treatment and 255 started on STR. Six patients received a modified STR. Among 249 patients on standardised STR, 207 (83·1%) were cured relapse-free, eight (3·2%) had failure, 23 (9·2%) died, seven (2·8%) were lost to follow-up and four (1·6%) relapsed. The risk of unfavourable outcome was higher in patients with initial resistance to fluoroquinolones (aOR 20·4, 95%CI:5·6-74·6) and very severely underweight (aOR 3·9, 95%CI:1·5-10·1). Successful outcome was not affected by initial resistance to companion drugs. Serious ototoxicity was reported in eight patients (3·2%).. A comprehensive nationwide approach to multidrug-resistant tuberculosis management using the STR was feasible and successful. Outcomes were not affected by initial resistance to companion drugs. Our study confirms the effectiveness and safety of the STR.. Damien Foundation and Institute of Tropical Medicine-Antwerp.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antitubercular Agents; Communicable Disease Control; Drug Resistance, Multiple, Bacterial; Feasibility Studies; Female; Fluoroquinolones; Follow-Up Studies; Humans; Male; Middle Aged; Niger; Rifampin; Tuberculosis, Multidrug-Resistant; Young Adult

To determine the accuracy of multiplex real-time PCR (Anyplex™ II MTB/MDR kit) in detecting Isoniazid (INH)- and Rifampin (RIF)-resistant Mycobacterium tuberculosis strains from various clinical specimens. The performance of Anyplex™ II MTB/MDR kit in detecting INH- and RIF-resistant M. tuberculosis compared to the conventional drug susceptibility tests by Mycobacterial Growth Indicator Tube (MGIT). A total of 430 clinical samples had positive results for M. tuberculosis from both Anyplex™ II MTB/MDR kit assay and mycobacterial cultures by MGIT method. When compared to MGITs, the sensitivity and specificity of Anyplex™ II MTB/MDR kit in detecting INH-resistant TB were 85.71% and 99.75%, respectively. For the detection of MDR-TB, the sensitivity and specificity of the test were 82.35% and 99.76%, respectively. The positive predictive values and negative predictive values to detect INH-resistant TB were 96.77% and 98.75%, respectively. Anyplex™ II MTB/MDR kit can be used to rapidly detect isoniazid and rifampicin resistances. It has a high sensitivity, specificity and PPV in detecting INH-resistant TB and MDR-TB. This test can be used as an alternative test to Xpert MTB/RIF because it can rapidly detect both INH-resistant TB and RIF-resistant TB.

Topics: Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Real-Time Polymerase Chain Reaction; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

Topics: Humans; Isoniazid; Pyrazinamide; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Topics: Humans; Isoniazid; Pyrazinamide; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Tuberculosis (TB) remains a main hurdle for national programs due to increase in drug resistance to antitubercular drugs. World Health Organization (WHO)-endorsed Line Probe Assay, Genotype MTBDRsl Ver 2.0, gives opportunity for rapid diagnosis and molecular characterization of different mutations in drug targets of fluoroquinolone (FQ) and second-line injectable drugs (SLID). We, retrospectively, analyzed the data of Genotype MTBDRsl Ver 2.0 from January 2018 to June 2018. A total of 863 isolates of

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antitubercular Agents; Child; Extensively Drug-Resistant Tuberculosis; Female; Genotype; Humans; India; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant; Young Adult

Topics: Cohort Studies; HIV Infections; Humans; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

India accounts for quarter of global rifampin-resistant/multi-drug resistant-tuberculosis (RR/MDR-TB). Knowledge on risk-factors and distribution of MDR-TB at district level is limited.. Study prevalence and risk factors of MDR-TB in tuberculosis patients in hilly districts of Himachal Pradesh, India.. Between July 2012-June 2013, TB patients registered under the Revised National Tuberculosis Control Program in Kangra and Una districts suspected of MDR-TB were referred for Xpert® MTB/RIF testing at the Delek Hospital, Dharamsala by the district TB Office.. Of 378 patients enrolled (median age: 45 years; 85% males), 18% (n = 68) were rifampin-resistant. Among Xpert positives (n = 305), distributions of RR-TB were: 10% (n = 9/89) for recurrent cases who had received TB treatment for <2-months, 15% each for new (n = 9/59) or recurrent cases (n = 5/34) remaining smear positive between 2 and 4 months of treatment, 36% (n = 41/113) for treatment failures, and 40% (n = 2/5) for loss to follow-ups. Of the sputum-smear positives, 15% (n = 51/338) were Xpert negative. Seeking care in the private sector was associated with higher risk of RR-TB (OR:1.85; 95% CI:0.87-3.9).. Prevalence of RR-TB is generally high in patients suspected of MDR-TB in the hilly districts of Himachal Pradesh. High prevalence during early phase of treatment can suggest primary transmission of DR-TB. Universal drug susceptibility testing and innovative case finding strategies will benefit patients living in mountain districts with inadequate access to healthcare. The high proportion of sputum-smear positive but Xpert negative cases may be due to non-tubercular mycobacterial disease.

Topics: Adult; Antibiotics, Antitubercular; Drug Resistance, Bacterial; Female; Health Services Accessibility; Humans; India; Male; Middle Aged; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Patient Acceptance of Health Care; Prevalence; Private Sector; Rifampin; Risk Factors; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Clinical Protocols; Humans; Rifampin; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Delayed Diagnosis; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Rwanda; Time-to-Treatment; Tuberculosis, Multidrug-Resistant

Re-treatment pulmonary tuberculosis (PTB) has a high risk of being multi-drug- or rifampicin-resistant tuberculosis (MDR/RR-TB). The Xpert MTB/RIF assay possesses high efficacy for the evaluation of rifampicin resistance. The aim of the present study was to assess the benefit of the Xpert MTB/ RIF assay in the screening and treatment of MDR/RR-TB in re-treatment PTB patients.. Patients with suspected re-treatment PTB were prospectively enrolled and divided into Xpert MTB/RIF and mycobacterial tuberculosis (MTB) culture groups. No Xpert MTB/RIF assay was carried out in the MTB culture group. The diagnostic performance and turn-around time (TAT) of MDR/RRTB detection and the culture results of MDR/RR-TB patients following two-month chemotherapy in two groups were calculated and compared.. Using phenotypic DST as a reference standard, the positive predictive value of Xpert MTB/RIF for the detection of RR-TB and MDR-TB among re-treatment PTB patients was 90.72% and 77.32%, respectively. The Xpert MTB/RIF group had a significantly shorter interval for the initiation of anti-MDR/ RR-TB treatment {1 [1-1] vs. 52 [47-57] days, P<0.0001}; and following two-month chemotherapy, the percentage of positive culture MDR/RR-TB patients in the Xpert MTB/RIF group was significantly reduced (24.18% vs. 50%, P=0.0003).. Xpert MTB/RIF can accurately screen MDR/RR-TB among re-treatment PTB patients, reducing both the turn-around time for therapy initiation and the percentage of positive culture MDR/ RR-TB patients following two-month chemotherapy. This is not only beneficial for treatment but also for reducing MDR-TB transmission. We recommend that re-treatment PTB patients receive anti-RR/TB chemotherapy following a positive RFP resistance result in the Xpert MTB/RIF assay.

Topics: Adult; Bacteriological Techniques; China; Cohort Studies; Female; Humans; Male; Middle Aged; Mycobacterium tuberculosis; Prospective Studies; Reinfection; Rifampin; Tuberculosis, Multidrug-Resistant

Zimbabwe is one of the thirty countries globally with a high burden of multidrug-resistant tuberculosis (TB) or rifampicin-resistant TB (MDR/RR-TB). Since 2010, patients diagnosed with MDR/RR-TB are being treated with 20-24 months of standardized second-line drugs (SLDs). The profile, management and factors associated with unfavourable treatment outcomes of MDR/RR TB have not been systematically evaluated in Zimbabwe.. To assess treatment outcomes and factors associated with unfavourable outcomes among MDR/RR-TB patients registered and treated under the National Tuberculosis Programme in all the district hospitals and urban healthcare facilities in Zimbabwe between January 2010 and December 2015.. A cohort study using routinely collected programme data. The 'death', 'loss to follow-up' (LTFU), 'failure' and 'not evaluated' were considered as "unfavourable outcome". A generalized linear model with a log-link and binomial distribution or a Poisson distribution with robust error variances were used to assess factors associated with "unfavourable outcome". The unadjusted and adjusted relative risks were calculated as a measure of association. A. Of the 473 patients in the study, the median age was 34 years [interquartile range, 29-42] and 230 (49%) were males. There were 352 (74%) patients co-infected with HIV, of whom 321 (91%) were on antiretroviral therapy (ART). Severe adverse events (SAEs) were recorded in 118 (25%) patients; mostly hearing impairments (70%) and psychosis (11%). Overall, 184 (39%) patients had 'unfavourable' treatment outcomes [125 (26%) were deaths, 39 (8%) were lost to follow-up, 4 (<1%) were failures and 16 (3%) not evaluated]. Being co-infected with HIV but not on ART [adjusted relative risk (aRR) = 2.60; 95% CI: 1.33-5.09] was independently associated with unfavourable treatment outcomes.. The high unfavourable treatment outcomes among MDR/RR-TB patients on standardized SLDs were coupled with a high occurrence of SAEs in this predominantly HIV co-infected cohort. Switching to individualized all oral shorter treatment regimens should be considered to limit SAEs and improve treatment outcomes. Improving the ART uptake and timeliness of ART initiation can reduce unfavourable outcomes.

Topics: Adolescent; Adult; Child; Child, Preschool; Cohort Studies; Female; Humans; Male; Middle Aged; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Young Adult; Zimbabwe

Studying within-host genetic diversity of Mycobacterium tuberculosis (Mtb) in patients during treatment may identify adaptations to antibiotic and immune pressure. Understanding the significance of genetic heteroresistance, and more specifically heterozygous resistance-associated variants (RAVs), is clinically important given increasing use of rapid molecular tests and whole genome sequencing (WGS).. We analyse data from six studies in KwaZulu-Natal, South Africa. Most patients (>75%) had baseline rifampicin resistance. Sputum was collected for culture at baseline and at between two and nine intervals until month six. Positive cultures underwent WGS. Mixed infections and reinfections were excluded from analysis.. Baseline Mtb overall genetic diversity (at treatment initiation or major change to regimen) was associated with cavitary disease, not taking antiretroviral therapy if HIV infected, infection with lineage 2 strains and absence of second-line drug resistance on univariate analyses. Baseline genetic diversity was not associated with six-month outcome. Genetic diversity increased from baseline to weeks one and two before returning to previous levels. Baseline genetic heteroresistance was most common for bedaquiline (6/10 [60%] of isolates with RAVs) and fluoroquinolones (9/62 [13%]). Most patients with heterozygous RAVs on WGS with sequential isolates available demonstrated RAV persistence or fixation (17/20, 85%). New RAVs emerged in 9/286 (3%) patients during treatment. We could detect low-frequency RAVs preceding emergent resistance in only one case, although validation of deep sequencing to detect rare variants is required.. In this study of single-strain Mtb infections, baseline within-host bacterial genetic diversity did not predict outcome but may reveal adaptations to host and drug pressures. Predicting emergent resistance from low-frequency RAVs requires further work to separate transient from consequential mutations.. Wellcome Trust, NIH/NIAID.

Topics: Adult; Antitubercular Agents; Cohort Studies; Diarylquinolines; Drug Resistance, Multiple, Bacterial; Female; Fluoroquinolones; Gene Expression Regulation, Bacterial; Genes, Bacterial; Genetic Variation; Host-Pathogen Interactions; Humans; Male; Metabolic Networks and Pathways; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Rifampin; South Africa; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

The MDR/MTB ELITe MGB® Kit on the ELITe InGenius® platform (ELITechGroup SpA, Italy) is the first system for simultaneous detection of the Mycobacterium tuberculosis complex (MTBc) genome and the main mutations responsible for resistance to Isoniazid (inhA, katG) and Rifampicin (rpoB), from decontaminated and heat inactivated samples. In this study we compared the performance of the MDR/MTB ELITe MGB® Kit (ELITe) with culture in 100 pulmonary and 160 extra-pulmonary samples. The sensitivity and specificity of ELITe compared to culture for pulmonary samples were 98.0% and 98.0% respectively; for extra-pulmonary samples the overall sensitivity was 86.3% (80% for urine, 85% for biopsy and gastric aspirate and 95% for cavitary fluid) and specificity was 100%. Genotypic Isoniazid and Rifampicin susceptibility typing was feasible in 96% of sputum MTBc-positive samples and 43% of extra-pulmonary samples; all samples were found to be drug susceptible by phenotypic and ELITe (100% agreement). Detection of mutations in the rpoB, kat G or inhA genes was evaluated on 300 spiked samples (60 per biological matrix) and all resistance profiles were correctly identified by ELITe. Molecular agreement between ELITe and Xpert was 98.0% and 93.3% for pulmonary and extra-pulmonary samples, respectively. In conclusion, our results provide evidence to support the use of MDR/MTB ELITe MGB® Kit in combination with ELITe InGenius® for the diagnosis of MTBc and the detection of Rifampicin and Isoniazid resistance-related mutations in both pulmonary and extra-pulmonary samples. This system simplifies the laboratory workflow, shortens report time and is an aid in choosing appropriate therapeutic treatment and patient management.

Topics: Antibiotics, Antitubercular; Biopsy; Drug Resistance, Bacterial; Genotype; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Reagent Kits, Diagnostic; Reproducibility of Results; Retrospective Studies; Rifampin; ROC Curve; Sensitivity and Specificity; Temperature; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Tuberculosis drug resistance (DR) is a global problem that is not fully elucidated. Previously, overexpression of

Topics: Antitubercular Agents; Bacterial Proteins; Genes, Bacterial; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Meta-analyses on impact of isoniazid-resistant tuberculosis informed the World Health Organization recommendation of a levofloxacin-strengthened rifampicin-based regimen. We estimated the effect of initial rifampicin resistance (Rr) and/or isoniazid resistance (Hr) on treatment failure or relapse. We also determined the frequency of missed initial and acquired Rr to estimate the impact of true Hr.. Retrospective analysis of 7291 treatment episodes with known initial isoniazid and rifampicin status obtained from individual patient databases maintained by the Damien Foundation Bangladesh over 20 years. Drug susceptibility test results were confirmed by the programme's designated supra-national tuberculosis laboratory. To detect missed Rr among isolates routinely classified as Hr, rpoB gene sequencing was done randomly and on a sample selected for suspected missed Rr.. Initial Hr caused a large recurrence excess after the 8-month regimen for new cases (rifampicin for two months), but had little impact on rifampicin-throughout regimens: (6 months, new cases; 3.8%; OR 0.8, 95%CI:0.3,2.8; 8 months, retreatment cases: 7.3%, OR 1.8; 95%CI:1.3,2.6). Rr was missed in 7.6% of randomly selected "Hr" strains. Acquired Rr was frequent among recurrences on rifampicin-throughout regimens, particularly after the retreatment regimen (31.9%). It was higher in mono-Hr (29.3%; aOR 3.5, 95%CI:1.5,8.5) and poly-Hr (53.3%; aOR 10.2, 95%CI 4.4,23.7) than in susceptible tuberculosis, but virtually absent after the 8-month new case regimen. Comparing Bangladesh (low Rr prevalence) with a high Rr prevalence setting,true Hr corrected for missed Rr caused only 2-3 treatment failures per 1000 TB cases (of whom 27% were retreatments) in both.. Our analysis reveals a non-negligible extent of misclassifying as isoniazid resistance of what is actually missed multidrug-resistant tuberculosis. Recommending for such cases a "strengthened" regimen containing a fluoroquinolone provokes a direct route to extensive resistance while offering little benefit against the minor role of true Hr tuberculosis in rifampicin-throughout first-line regimen.

Topics: Adult; Antitubercular Agents; Bangladesh; Diagnostic Errors; Drug Resistance; Fluoroquinolones; Humans; Isoniazid; Recurrence; Retrospective Studies; Rifampin; Treatment Failure; Treatment Outcome; Tuberculosis, Multidrug-Resistant

Males are at an increased risk of tuberculosis (TB) disease compared to females. Additionally, several risk factors for multidrug-resistant (MDR) or rifampicin-resistant (RR) TB disease are more common in males, hence male TB patients may have a higher relative risk of MDR/RR-TB than female TB patients.We used sex-disaggregated data of TB patients reported to the World Health Organization for 106 countries to calculate male-to-female (M:F) risk ratios of having MDR/RR-TB.There was no evidence of either sex being more at risk of MDR/RR-TB in 81% (86 out of 106) of countries, with an overall random-effects weighted M:F risk ratio of 1.04 (95% CI 0.97-1.11). In 12% (13 out of 106) of countries there was evidence that males were more at risk, while in 7% (seven out of 106), females were more at risk. The risk of having TB that was MDR/RR increased for males compared to females as MDR/RR-TB incidence increased, and was higher for males than females in the former Soviet Union, where the risk ratio was 1.16 (1.06-1.28). Conversely, the risk increased for females compared to males as gross domestic product purchase power parity increased, and was higher for females than males in countries where the majority of TB burden was found in the foreign-born population, where the risk ratio was 0.84 (0.75-0.94).In general, the risk of MDR/RR-TB, among those with TB, is the same for males as for females. However, males in higher MDR/RR-TB burden countries, particularly the former Soviet Union, face an increased risk that their infection is MDR/RR-TB, highlighting the need for a sex-differentiated approach to TB case-finding and care.

Topics: Antitubercular Agents; Female; Humans; Male; Mycobacterium tuberculosis; Odds Ratio; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant; World Health Organization

Tuberculosis treatment includes broad-spectrum antibiotics such as rifampicin, streptomycin and fluoroquinolones, which are also used against other pathogenic bacteria. We developed Drug Resistance Associated Genes database (DRAGdb), a manually curated repository of mutational data of drug resistance associated genes (DRAGs) across ESKAPE (i.e. Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.) pathogens, and other bacteria with a special focus on Mycobacterium tuberculosis (MTB). Analysis of mutations in drug-resistant genes listed in DRAGdb suggested both homoplasy and pleiotropy to be associated with resistance. Homoplasy was observed in six genes namely gidB, gyrA, gyrB, rpoB, rpsL and rrs. For these genes, drug resistance-associated mutations at codon level were conserved in MTB, ESKAPE and many other bacteria. Pleiotropy was exemplified by a single nucleotide mutation that was associated with resistance to amikacin, gentamycin, rifampicin and vancomycin in Staphylococcus aureus. DRAGdb data also revealed that mutations in some genes such as pncA, inhA, katG and embA,B,C were specific to Mycobacterium species. For inhA and pncA, the mutations in the promoter region along with those in coding regions were associated with resistance to isoniazid and pyrazinamide respectively. In summary, the DRAGdb database is a compilation of all the major MTB drug resistance genes across bacterial species, which allows identification of homoplasy and pleiotropy phenomena of DRAGs.

Topics: Antitubercular Agents; Bacterial Proteins; Data Curation; Databases, Genetic; DNA, Bacterial; Drug Resistance, Multiple, Bacterial; Extensively Drug-Resistant Tuberculosis; Fluoroquinolones; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Pyrazinamide; Rifampin; Sequence Analysis, DNA; Tuberculosis, Multidrug-Resistant

The human- and animal-adapted lineages of the Mycobacterium tuberculosis complex (MTBC) are thought to have expanded from a common progenitor in Africa. However, the molecular events that accompanied this emergence remain largely unknown. Here, we describe two MTBC strains isolated from patients with multidrug resistant tuberculosis, representing an as-yet-unknown lineage, named Lineage 8 (L8), seemingly restricted to the African Great Lakes region. Using genome-based phylogenetic reconstruction, we show that L8 is a sister clade to the known MTBC lineages. Comparison with other complete mycobacterial genomes indicate that the divergence of L8 preceded the loss of the cobF genome region - involved in the cobalamin/vitamin B12 synthesis - and gene interruptions in a subsequent common ancestor shared by all other known MTBC lineages. This discovery further supports an East African origin for the MTBC and provides additional molecular clues on the ancestral genome reduction associated with adaptation to a pathogenic lifestyle.

Topics: Aged; DNA, Bacterial; Evolution, Molecular; Genetic Variation; Genome, Bacterial; Genomics; Genotype; Humans; Likelihood Functions; Limit of Detection; Male; Mutation; Mycobacterium tuberculosis; Phenotype; Phylogeny; Rifampin; Rwanda; Tuberculosis, Multidrug-Resistant; Uganda

Drug resistant tuberculosis (DR-TB) is challenging particularly in developing countries. As such, a previous investigation gave the first insight into the mutational status of the Rifampicin Resistance Determining Region (RRDR) of rpoB gene among a restricted number of MTB patients' residents in the Northern Morocco. The purpose of this study was to investigate rpoB mutation types and frequencies associated with resistance to Rifampicin in a larger panel of MTB patients and to evaluate the usefulness of these mutations to improve the diagnosis of resistance to Rifampicin. A panel of 301 consecutive sputum samples belonging to patients suscpected of having TB from Northern Morocco was collected at the Pasteur Institute of Tangier between 2014-2017. Samples were subjected to conventionel microbiological tests. Evaluation of rpoB muational status was assessed by PCR amplification and sequencing of the RRDR of the rpoB gene. DST results showed that 26.4% of strains were MDR. Sequencing results reported single point mutations in 36 of 65 RIFR isolates of which two had two mutations. Aminoacid substitutions in the codon Ser531Leu occurred at the highest frequency (34.46%). Overall, 10 aminoacid substitutions have been registered, and the H526S substitution was reported for the first time. The present study highlighted that resistance to RIF is a reliable marker of MDR-TB, the common mutations successfully detected in the rpoB 531, rpoB526 and rpoB516 codons provide a foundation for the implementation of molecular approaches such as Hain and GeneXpert as a routine tests to detect DR-TB. However, considerable work is still necessary to identify extensive mutations associated with DR-TB.

Topics: Adult; Antitubercular Agents; Female; Genotype; Humans; Male; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Polymerase Chain Reaction; Rifampin; Tuberculosis, Multidrug-Resistant

P-glycoprotein (PGP) overexpression may be one of the operating mechanisms of suboptimal responses to antitubercular treatment (ATT) in patients with lymph node tuberculosis. This might become responsible for the development of drug resistance later due to exposure of subtherapeutic concentrations to the mycobacteria. In this study we aim to study the prevalence of PGP expression and function and its relationship with serum concentrations of Rifampicin in consecutive patients with lymph node tuberculosis.. All newly diagnosed treatment naïve subjects with a confirmed diagnosis of tubercular lymphadenopathy were included in the study and the expression and function of PGP in blood was determined by flowcytometry at baseline and after two months of treatment. Serum levels of Rifampicin was measured at 2 months by high performance liquid chromatography (HPLC). The mean net PGP expression expressed as percent and relative fluorescence indices (RFI) of PGP expression and function respectively was compared at baseline at 2 months and was also correlated with serum rifampicin levels.. The mean net PGP expression, RFI of PGP expression and RFI of PGP function were significantly higher in patients with lymph node tuberculosis as compared to healthy controls and the mean net PGP expression and RFI of PGP expression were significantly higher at 2 months as compared to baseline (25.64 ± 5.18% vs. 27.68 ± 4.89%, 4.34 ± 1.09% vs. 4.95 ± 1.55). There was no significant difference in RFI of PGP expression and RFI of PGP function between the poor-responders and responders at baseline and 2 months however there was a trend towards significantly higher net PGP expression amongst poor responders at baseline. The mean serum rifampicin levels were 10.74 ± 2.36 μg/ml in the responder group and 7.86 ± 1.21 μg/ml in the non-responder group and the difference between the two was statistically significant (p = 0.004).. Overexpression of PGP is common in patients with lymph node tuberculosis and leads to lower concentrations of Rifampicin in blood which subsequently may give rise to development of drug resistance. This is also responsible for poor therapeutic responses in these patients. Nonspecific inhibitors of PGP may be used in conjunction with ATT to augment therapeutic response in such cases.

Topics: Adolescent; Adult; Antitubercular Agents; ATP Binding Cassette Transporter, Subfamily B, Member 1; Case-Control Studies; Drug Resistance, Bacterial; Female; Humans; Male; Pilot Projects; Rifampin; Treatment Outcome; Tuberculosis, Lymph Node; Tuberculosis, Multidrug-Resistant; Young Adult

India is determined to eliminate TB by 2025 despite being a high burden country. Revised National Tuberculosis Control Programme (RNTCP) is being strengthened with introduction of Universal Drug Susceptibility Testing (UDST) for Rifampicin to achieve the elimination status.. We used a before-after comparison of baseline and intervention periods (12 months each) and analyzed data viz CBNAAT performed and case detection for both drug sensitive and drug resistant TB cases.. After implementation of Universal DST, CBNAAT performed raised from 1252 to 3137 (increased by 2.5 times); Rif sensitive cases detected raised from 458 to 1241 (increased by 2.7 times) and Rif resistant cases detected raised from 54 to 82 (increased by 1.5 times) during baseline period (2017) and intervention period (2018).. We conclude that introduction of UDST for Rifampicin in RNTCP has given a significant impact with increased case detection in our study.

Topics: Antitubercular Agents; Disease Eradication; Drug Resistance, Bacterial; Humans; India; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Rifampin; Tuberculosis, Multidrug-Resistant

The emergence of drug-resistant tuberculosis (DR-TB) is a major healthcare concern worldwide. Here, we analyzed age-related trends in DR-TB rates in South Korea.. Drug susceptibility test results were collected from patients with culture-confirmed TB between 2015 and 2018 from eight university-affiliated hospitals. Patients were divided into three subgroups: younger (15-34 years), middle (35-59 years), and older (≥60 years) to compare drug-resistance patterns. To evaluate trends in age-stratified drug-resistance, chi-square test for linear trends was performed.. Among enrolled native patients aged ≥15 years, 4.1% (179/4417), 1.2% (53/4417) and 7.2% (316/4417) were multidrug-resistant TB (MDR-TB), rifampicin-mono-resistant TB (RR-TB), and isoniazid-mono-resistant TB (Hr-TB), respectively. Proportions of Hr-TB cases were 5.4% (40/734), 7.2% (114/1593), and 7.8% (162/2090) in the younger, middle and older age groups, respectively. MDR/RR-TB case rates decreased significantly with age from 8.6% (63/734) in younger age group to 3.3% (68/2090) in older age group. Fluoroquinolone resistance was highest among second-line drugs, and there were no differences in resistance to fluoroquinolones and second-line injectable drugs among the three age groups.. The number of MDR/RR-TB cases was highest in young patients. Effective public health interventions should include increased focus on rifampicin resistance in young patients.

Topics: Adolescent; Adult; Age Factors; Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Female; Fluoroquinolones; Humans; Isoniazid; Male; Middle Aged; Mycobacterium tuberculosis; Republic of Korea; Retrospective Studies; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Young Adult

Topics: Adult; Antitubercular Agents; Drug Evaluation, Preclinical; Drug Resistance, Multiple, Bacterial; Female; Genotype; Humans; Indonesia; Kanamycin; Male; Microbial Sensitivity Tests; Middle Aged; Molecular Epidemiology; Mutation; Mycobacterium tuberculosis; Phenotype; Phylogeny; Rifampin; Streptomycin; Tuberculosis, Multidrug-Resistant; Whole Genome Sequencing

BD MAX MDR-TB assay is a new molecular platform for the detection of Mycobacterium tuberculosis complex (MTBC) in clinical specimens and simultaneous detection of resistance toward isoniazid and rifampicin. This study assessed the assay's diagnostic accuracy by using pre-characterized MTBC culture-negative (n = 257), smear-negative/MTBC culture-positive (n = 93), and smear-positive/MTBC culture-positive (n = 153) respiratory specimens. Compared with culture, the overall sensitivity and specificity of BD MAX MDR-TB were 86.6% and 100%, respectively; sensitivities for smear-positive and smear-negative samples were 100% and 64.5%. Sensitivity and specificity for isoniazid and rifampicin resistance were 58.3% (biased low due to sample collection strategy in low prevalence setting), 99.3%, 100%, and 98.2%, compared with phenotypic drug resistance testing and 100%, 99.4%, 100%, and 99.4%, compared with GenoType MTBDRplus. In conclusion, BD MAX MDR-TB is an accurate assay for the diagnostic detection of MTBC in respiratory samples and its resistance toward the most important anti-TB drugs isoniazid and rifampicin. Due to its medium to high throughput, good validity, and ease of use, the assay will be of great benefit for medium-sized to large TB diagnostic centers.

Topics: Genetic Markers; Humans; Isoniazid; Molecular Diagnostic Techniques; Mycobacterium tuberculosis; Reference Standards; Rifampin; Tuberculosis, Multidrug-Resistant

Topics: Humans; Nitroimidazoles; Oxazoles; Retrospective Studies; Rifampin; South Africa; Tuberculosis, Multidrug-Resistant

Tuberculosis is an infectious disease, which requires special medical attention due to the emergence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains. The present study aimed to assess drug resistance to first-line anti-mycobacterial drugs, including rifampin (RIF), isoniazid (INH), and ethambutol (EMB), as well as second-line drugs, including ofloxacin (OFX), kanamycin (KAN), amikacin (AMK), and capreomycin (CAP). The following eight loci were investigated to evaluate drug resistance: rpoB, katG, inhA, and embB, associated with resistance to RIF, INH, and EMB and gyrA, rrs, eis, and tlyA, associated with resistance to OFX, AMK, KAN, and CAP. A total of 482 patients with tuberculosis, who were referred to Molla Haadi Sabzevari Healthcare Center (Isfahan, Iran) during 2014-2017, were studied. Of 482 patients with tuberculosis, 32 (6.63%) Mycobacterium tuberculosis isolates were resistant to the first-line anti-mycobacterial drugs. Overall, 23 (71.8%), 13 (40.6%), and 3 (9.3%) isolates were resistant to INH, RIF, and EMB, respectively. Also, 13 (100%), 6 (46.1%), and 1 (7.6%) out of 13 MDR/RIF-resistant isolates were resistant to CAP and KAN, AMK, and OFX, respectively. Among the eight loci, non-synonymous substitutions were observed in rpoB (n = 7), katG (n = 10), inhA (n = 7), gyrA (n = 13), and rrs (n = 3), whereas synonymous substitutions were seen in tlyA and gyrA. On the other hand, no mutation was detected in embB or eis. Based on the present results, mutations in the eis promoter region and embB locus may not be involved in resistance to KAN and EMB in our study population. Also, the gyrA Asp94Asn mutation may be an indicator of resistance to OFX. We did not detect any XDR isolates, whereas MDR and pre-XDR isolates were found, which can be alarming.

Topics: Adult; Aged; Aged, 80 and over; Amikacin; Antitubercular Agents; Capreomycin; DNA Mutational Analysis; Drug Resistance, Multiple, Bacterial; Ethambutol; Female; Genetic Variation; Genotype; Humans; Iran; Isoniazid; Kanamycin; Male; Middle Aged; Mycobacterium tuberculosis; Ofloxacin; Rifampin; Sequence Analysis, DNA; Tuberculosis, Multidrug-Resistant

The main advantage of GeneXpert MTB/RIF® (Xpert) molecular diagnostic technology is the rapid detection of M.tuberculosis DNA and mutations associated with rifampicin (RIF) resistance for timely initiation of appropriate treatment and, consequently, preventing further transmission of the disease. We assessed time to treatment initiation and treatment outcomes of RIF-resistant and RIF-susceptible TB patients diagnosed and treated in Vladimir TB Dispensary, Russia in 2012, before and after implementation of GeneXpert MTB/RIF® diagnostic technology.. All adult patients suspected of having TB during February-December 2012 underwent a clinical examination, chest x-ray, microscopy, culture, and phenotypic drug susceptibility testing (DST). Starting August 2012 Xpert diagnostic technology became available in the facility. We used logistic regression to compare treatment outcomes in pre-Xpert and post-Xpert periods. Kaplan-Meier curves and log-rank test were used to compare the time to treatment initiation between the groups.. Of 402 patients screened for TB during February-December 2012, 338 were diagnosed with TB (280 RIF-susceptible, 58 RIF-resistant). RIF-resistant patients in the post-Xpert group started treatment with second-line drugs (SLD) earlier than those in pre-Xpert group (median 11 vs. 37 days, Log-rank p = 0.02). The hazard ratio for time to SLD treatment initiation was significantly higher in post-Xpert group (HR:2.06; 95%CI:1.09,3.89) compared to pre-Xpert group. Among the 53/58 RIF-resistant TB patients with available treatment outcome, 28 (53%) had successful outcomes (cured/completed treatment) including 15/26 (58%) in post-Xpert group versus 13/27 (48%) in pre-Xpert group. The observed difference, however, was not statistically significant (OR:0.69; 95%CI:0.23,2.06). Among RIF-susceptible TB cases time to treatment initiation was not significantly different between the groups (2 vs. 3 days, Log-rank p = 0.73). Of 252/280 RIF-susceptible TB cases with treatment outcome, 199 (79%) cases had successful outcome including 94/114 (82%) in post-Xpert group versus 105/138 (76%) in pre-Xpert group (OR:0.68; 95%CI:0.36,1.26).. We observed that availability of Xpert for initial diagnosis significantly reduced the time to SLD treatment for RIF-resistant patients in the Vladimir TB Dispensary. Although implementation of rapid diagnostics did not improve treatment outcomes, early diagnosis of MDR-TB is important for selection of appropriate treatment regimen and prevention of transmission of drug-resistant strains of TB.

Topics: Adolescent; Adult; Aged; Antibiotics, Antitubercular; DNA, Bacterial; Drug Resistance, Bacterial; Female; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Mutation; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Prospective Studies; Rifampin; Russia; Time-to-Treatment; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Young Adult

We analyzed 312 drug-resistant genomes of

Topics: Antitubercular Agents; Bacterial Proteins; DNA-Directed RNA Polymerases; HIV Infections; Humans; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Multi-drug resistance is a major challenge in the control of tuberculosis. Despite newer modalities for diagnosis and treatment, people are still suffering from this disease. Understanding the common gene mutations conferring rifampicin and isoniazid resistance is crucial for the implementation of effective molecular tools at local and national levels. Hence, this study aimed to evaluate the molecular detection of rifampicin and isoniazid-resistant gene mutations in M.tuberculosis isolates in Addis Ababa, Ethiopia.. Health Center-based cross-sectional study was conducted between January and September 2017 in Addis Ababa, Ethiopia. The collected sputum samples were processed for mycobacterial isolation and Region of difference 9 based polymerase chain reaction for species identification. To characterize the rifampicin and isoniazid-resistant M. tuberculosis isolates, a molecular genetic assay (GenoType MTBDRplus) was used; the assay is based on DNA-STRIP technology.. Culture positivity was confirmed in 82.6% (190/230) of smear-positive newly diagnosed pulmonary tuberculosis cases enrolled in the study. From 190 isolates 93.2% were sensitive for both rifampicin and isoniazid, and 6.8% of the isolates were resistant to at least one of the tested anti-TB drugs. Gene mutations were observed in all studied multidrug resistance-associated gene loci (rpoB, katG, and inhA). Two isolates exhibited heteroresistance, a mutated, as well as wild type sequences, were detected in the respective strains. MDR-TB case was observed in 1.1% (2/190) of the cases. All the MDR-TB cases were positive for HIV and found to have a history of prior hospital admission.. In our finding a relatively high prevalence of any drug resistance was observed and the overall prevalence of multidrug-resistant tuberculosis was 1.1%.The majority of drug-resistant isolates demonstrated common mutations. Heteroresistant strains were detected, signaling the existence of an M.tuberculosis population with variable responses to anti-tuberculosis drugs or of mixed infections.

Topics: Adolescent; Adult; Antitubercular Agents; Cross-Sectional Studies; DNA Mutational Analysis; DNA, Bacterial; Drug Resistance, Multiple, Bacterial; Ethiopia; Female; Genes, Bacterial; Genetic Loci; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Mutation; Mycobacterium tuberculosis; Polymerase Chain Reaction; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Young Adult

Tuberculosis (TB) is an ongoing public health care, with the state of affairs exacerbated by the growth of anti-TB drug-resistant forms in South Africa. Not much attention is given to zoonotic TB. Thus, this study aimed to determine the presence of rpoB mutations among Mycobacterium tuberculosis complex (MTBC) isolates of lymph nodes from slaughtered cattle. A count of 14,950 carcasses from selected abattoirs were examined for nodular lesions and enlarged lymph nodes; 376 lymph nodes were cultured for MTBC. Positive isolates were tested for drug sensitivity against three anti-TB drugs, rifampicin, isoniazid, and ethambutol, using the Lowenstein-Jensen proportion method. Rifampicin-resistant isolates were sequenced, and spoligotyping was performed for lineage classification. A total of 162 isolates were confirmed as MTBC and 42 isolates were resistant to rifampicin. All rifampicin-resistant isolates carried the H526D rpoB mutation, and almost all of them carried an additional nonsynonymous nucleotide substitution in the hot spot region, in three other codons (510, 516 and 522). In total, 5 different mutations at four codons are reported, including one isolate showing 3 of them which has never been reported in South Africa. In addition, we report 4 different spoligo patterns, with 34 isolates known and 8 unknown spoligotype international types. From the known clades, 5 (11.9%) isolates were identified as Bov_4 caprae lineage, 29 (69%) Beijing, and 8 (19.1%) remaining unknown clades. The detection of MTBC-resistant patterns from cattle lymph nodes (Eastern Cape, South Africa) necessitates the investigation of other possible routes of MTBC transmission.

Topics: Abattoirs; Animals; Antitubercular Agents; Bacterial Proteins; Cattle; DNA-Directed RNA Polymerases; Drug Resistance, Bacterial; Genotype; Lymph Nodes; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifampin; South Africa; Tuberculosis, Multidrug-Resistant

Implementation of an effective Tuberculosis Routine Surveillance System in low-income countries like Tanzania is problematic, despite being an essential tool for the detection and effective monitoring of drug resistant tuberculosis. Long delays in specimen transportation from the facilities to reference laboratory and results dissemination back to the health facilities, result in poor patient management, particularly where multidrug-resistant tuberculosis disease is present.. Following a detailed qualitative study, a pilot intervention of a revised Tuberculosis Routine Surveillance System was implemented in Mwanza region, Tanzania. This included the use of rapid molecular methods for the detection of both tuberculosis and drug resistance using Xpert MTB/RIF in some Mwanza sites, the use of Xpert MTB/RIF and Line Probe Assay at the Central Tuberculosis Reference Laboratory, a revised communication strategy and interventions to address the issue of poor form completion. A before and after comparison of the intervention on the number of drug resistant tuberculosis cases identified and the time taken for results feedback to the requesting site was reported.. The revised system for previously treated cases tested at the Central Reference Laboratory was able to obtain the following findings; the number of cases tested increased from 75 in 2016 to 185 in 2017. The times for specimen transportation from health facilities to the reference laboratory were reduced by 22% (from 9 to 7 days). The median time for the district to receive results was reduced by 36% (from 11 to 7 days). Overall the number of drug resistant tuberculosis cases starting treatment increased by 67% (from 12 to 20).. Detection of drug resistance could significantly be enhanced, and delays reduced by introduction of new technologies and improved routine surveillance system, including better communication using mobile applications such as 'WhatsApp' and close follow-ups. A larger scale study is now merited to ascertain if these benefits are robust across different contexts.

Topics: Antibiotics, Antitubercular; Communication; Delayed Diagnosis; Diagnostic Tests, Routine; Drug Resistance, Multiple, Bacterial; Epidemiological Monitoring; Health Facilities; Humans; Laboratories; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Pilot Projects; Prospective Studies; Qualitative Research; Rifampin; Specimen Handling; Tanzania; Tuberculosis, Multidrug-Resistant

Multidrug-resistant tuberculosis (MDR-TB) is a global health challenge. The emergence of MDR TB has contributed remarkably to the spread of tuberculosis and also poses a threat, which if not effectively addressed may wipe out the achievements of previous efforts in controlling tuberculosis.. This study was aimed at detecting MDR-TB among patients in a setting prevalent with tuberculosis and HIV in Southeast, Nigeria.. Sputum specimens collected from 740 suspected tuberculosis (TB) patients were screened for acid-fast bacilli (AFB). All the 111 AFB positive samples were subjected to culture on Lowenstein-Jensen (LJ) medium and Mycobacterium Growth Indicator Tube (MGIT) 960 TB system. The isolates were then confirmed as Mycobacterium tuberculosis using SD Bioline Rapid Diagnostic Tests before being subjected to drug susceptibility testing to first-line anti-TB drugs. MDR-TB was determined by isolates being resistant to both isoniazid and rifampicin. HIV testing was performed for participants included in the study using standard rapid diagnostic tests.. Out of the 111 AFB-positive sputum samples, 65 (58.6%) were culture-positive for Mycobacterium tuberculosis. MDR-TB was found in 2 ([3.1%] 95% CI = 0.0-7.3) of the culture-positive samples. The rate of TB and HIV coinfection was 7.7%. Maximum single-drug resistance was seen in ethambutol 12 ([18.5%] 95% CI = 9.0-27.9).. The MDR-TB rate of 3.1% found in this study was relatively low and efforts should be intensified to keep it low.

Topics: Antitubercular Agents; Cross-Sectional Studies; HIV Infections; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Nigeria; Predictive Value of Tests; Prevalence; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Young Adult

Tuberculosis (TB) is among the top 10 causes of mortality and the first killer among infectious diseases worldwide. One of the factors fuelling the TB epidemic is the global rise of multidrug resistant TB (MDR-TB). The aim of this study was to determine the magnitude and factors associated with MDR-TB in the Tigray Region, Ethiopia.. This study employed a facility-based cross-sectional study design, which was conducted between July 2018 and August 2019. The inclusion criteria for the study participants were GeneXpert-positive who were not under treatment for TB, PTB patients' ≥15 years of age and who provided written informed consent. A total of 300 participants were enrolled in the study, with a structured questionnaire used to collect data on clinical, sociodemographic and behavioral factors. Sputum samples were collected and processed for acid-fast bacilli staining, culture and drug susceptibility testing. Drug susceptibility testing was performed using a line probe assay. Logistic regression was used to analyze associations between outcome and predictor variables.. The overall proportion of MDR-TB was 16.7% (11.6% and 32.7% for new and previously treated patients, respectively). Of the total MDR-TB isolates, 5.3% were pre-XDR-TB. The proportion of MDR-TB/HIV co-infection was 21.1%. A previous history of TB treatment AOR 3.75; 95% CI (0.7-2.24), cigarette smoking AOR 6.09; CI (1.65-2.50) and patients who had an intermittent fever (AOR = 2.54, 95% CI = 1.21-5.4) were strongly associated with MDR-TB development.. The magnitude of MDR-TB observed among new and previously treated patients is very alarming, which calls for an urgent need for intervention. The high proportion of MDR-TB among newly diagnosed cases indicates ongoing transmission, which suggests the need for enhanced TB control program performance to interrupt transmission. The increased proportion of MDR-TB among previously treated cases indicates a need for better patient management to prevent the evolution of drug resistance. Assessing the TB control program performance gaps and an optimal implementation of the WHO recommended priority actions for the management of drug-resistant TB, is imperative to help reduce the current high MDR-TB burden in the study region.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antitubercular Agents; Cross-Sectional Studies; Ethiopia; Female; HIV Infections; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Rifampin; Risk Factors; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

Afghanistan is affected by one of the world's longest protracted armed conflicts, frequent natural disasters, disease outbreaks and large population movements and it suffers from a high burden of tuberculosis (TB), including rifampicin-resistant TB (RR-TB). The study shows Médecins Sans Frontières' experiences with care for patients with RR-TB in Kandahar Province. We describe the uptake of RR-TB treatment, how World Health Organisation criteria for the choice between the short and an individualized regimen were implemented, and treatment outcomes.. This is a retrospective cohort analysis of routinely collected data from RR-TB patients enrolled in care from 2016 until 2019. Descriptive analysis was performed to present characteristics of patients and treatment outcomes. Multivariable Cox analysis was performed to identify risk factors for having an unfavourable treatment outcome.. Out of 146 enrolled RR-TB patients, 112 (76.7%) started treatment: 41 (36.6%) and 71 (63.4%) with the short and individualized treatment regimen, respectively. Of 82 with results for fluoroquinolone susceptibility, 39 (47.6%) had fluoroquinolone-resistant TB. Seven patients with initially fluoroquinolone-resistant TB and three pregnant women started the short regimen and 18 patients eligible for the short regimen started the injectable-free individualized regimen. Overall, six-month smear and culture conversion were 98.7% and 97.1%, respectively; treatment success was 70.1%. Known initial fluoroquinolone resistance (aHR 3.77, 95%CI:1.53-9.27) but not choice of regimen predicted having an unfavourable outcome.. Even though criteria for the choice of treatment regimen were not applied strictly, we have achieved acceptable outcomes in this cohort. To expand RR-TB care, treatment regimens should fit provision at primary health care level and take patient preferences into account.

Topics: Adolescent; Adult; Afghanistan; Antitubercular Agents; Female; Fluoroquinolones; Humans; Male; Pregnancy; Retrospective Studies; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant; World Health Organization; Young Adult

We investigated whether companion drug resistance was associated with adverse outcomes of the shorter multidrug-resistant tuberculosis (MDR-TB) treatment regimen in Bangladesh after adjustment for fluoroquinolone resistance.. MDR-TB/rifampicin-resistant tuberculosis patients registered for treatment with a standardized gatifloxacin-based shorter MDR-TB treatment regimen were selected for the study. Drug resistance was determined by the proportion method, gatifloxacin and isoniazid minimum inhibitory concentration testing for selected isolates, and whole-genome sequencing.. Low-level fluoroquinolone resistance and high-level fluoroquinolone resistance were the most important predictors of adverse outcomes, with pyrazinamide resistance having a significant yet lower impact. In patients with fluoroquinolone-/second-line-injectable-susceptible tuberculosis, non-eligibility for the shorter MDR-TB treatment regimen (initial resistance to pyrazinamide, ethionamide, or ethambutol) was not associated with adverse outcome (adjusted odds ratio 1.01; 95% confidence interval 0.4-2.8). Kanamycin resistance was uncommon (1.3%). Increasing levels of resistance to isoniazid predicted treatment failure, also in a subgroup of patients with high-level fluoroquinolone-resistant tuberculosis.. Our results suggest that resistance to companion drugs in the shorter MDR-TB treatment regimen, except kanamycin resistance, is of no clinical importance as long as fluoroquinolone susceptibility is preserved. Hence, contrary to current WHO guidelines, exclusions to the standard regimen are justified only in the case of fluoroquinolone resistance. and possibly kanamycin resistance.

Topics: Adolescent; Adult; Aged; Antitubercular Agents; Bangladesh; Child; Child, Preschool; Clinical Protocols; Ethambutol; Female; Fluoroquinolones; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Pyrazinamide; Rifampin; Time Factors; Tuberculosis, Multidrug-Resistant; Young Adult

The purpose of this study was to evaluate the current status and trends in the coverage of molecular drug susceptibility testing (mDST), and the impact of mDST on the time to multidrug-resistant tuberculosis (MDR-TB) treatment initiation in Korea.. We included confirmed rifampin-resistant (RR)/MDR-TB patients who submitted application forms for novel drug uses to the National TB Expert Review Committee from September 1, 2016 to November 30, 2019. We retrospectively reviewed their medical records.. Of the 621 MDR/RR-TB patients, mDST was performed in 442 (71.2%); Xpert MTB/RIF (Xpert) alone in 109 (17.6%), MTBDR. mDST coverage is gradually increasing and contributes to reducing the time to MDR-TB treatment initiation. Further efforts are needed to achieve universal access to mDST and to properly integrate mDST into routine clinical practice.

Topics: Adult; Aged; Antitubercular Agents; Databases, Factual; Female; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Proportional Hazards Models; Retrospective Studies; Rifampin; Time-to-Treatment; Tuberculosis, Multidrug-Resistant

Phenotypic testing for drug susceptibility of

Topics: Antitubercular Agents; Drug Resistance, Bacterial; Humans; Luciferases; Luminescent Measurements; Microbial Sensitivity Tests; Mycobacteriophages; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Topics: Drug Resistance, Bacterial; Fluoresceins; Humans; Mali; Molecular Diagnostic Techniques; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant

The potential of genetic testing for rapid and accurate diagnosis of drug-resistant Mycobacterium tuberculosis strains is vital for efficient treatment and reduction in dissemination. MTBDR plus assays rapidly detect mutations related to drug resistance and wild type sequences allied with susceptibility. Although these methods are promising, the examination of molecular level performance is essential for improved assay result interpretation and continued diagnostic development. Therefore this study aimed to determine novel mutations that were inhibiting wild type probe hybridization in the Line probe assay by DNA sequencing. Using data collected from Line Probe assay (GenoType MTBDRplus assay) the contribution of absent wild type probe hybridization to the detection of rifampicin resistance was assessed via comparison to a reference standard method i.e. DNA sequencing.. Sequence analysis of the rpoB gene of 47 MTB resistant strains from clinical specimens showed that 37 had a single mutation, 9 had double mutations and one had triple mutations in the ropB gene.. The absence of wild type probe hybridization without mutation probe hybridization was mainly the result of the failure of mutation probe hybridization and the result of the novel or rare mutations. Additional probes are necessary to be included in the Line probe assay to improve the detection of rifampicin-resistant Mycobacterium tuberculosis strains.

Topics: Antibiotics, Antitubercular; Bacterial Proteins; DNA Mutational Analysis; DNA Probes; DNA-Directed RNA Polymerases; Drug Resistance, Bacterial; Humans; In Situ Hybridization; Mutation; Mycobacterium tuberculosis; Rifampin; Sequence Analysis, DNA; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Rapid and easy detection of nucleotide point mutations in bacterial pathogens associated with drug resistance is essential for the proper use of antimicrobials. Here, we developed a rapid and simple method for the detection of mutations using Loop-mediated isothermal amplification (LAMP) combined with the single-tag hybridization (STH) chromatographic printed array strips (PAS) method. This procedure is able to detect four mutations (C1349 T, A1295C, G1303 T, A1304 T) in Rifampicin Resistance Determining Region (RRDR) of rifampicin-resistant Mycobacterium tuberculosis (RR-TB), simultaneously. LAMP reactions contained a LAMP primer and eight allele-specific primers for each mutation. The allele-specific primers products were detected by nucleic acid chromatography using PAS. Four detection lines were detected there, one of which was detected at different positions depend on the wild type and the mutant type. We carried out the four mutations detection using 31 genomic DNA (2 A1295T, 1 G1303 T, 6 A1304 T, 22 C1349 T) from clinical isolate. The mutations have been confirmed by sequence analysis. The detection results were completely consistent with the sequence analysis. In the present study, four mutations could be detected, but only 60% of RR-TB could be detected with these four. It is expected that the detection rate will increase by adding more mutant primers. The combined LAMP and STH chromatographic PAS method is a simple and rapid method for detecting point mutations in clinical isolates as a point-of-care testing (POCT) technique. In addition, it does not require special equipment and can meet the demand in areas where drug-resistant bacteria are endemic, such as developing countries.

Topics: Bacterial Proteins; Bacterial Typing Techniques; Base Sequence; Chromatography; DNA-Directed RNA Polymerases; DNA, Bacterial; Genes, Bacterial; Humans; Microbial Sensitivity Tests; Molecular Diagnostic Techniques; Mutation; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

Pakistan is among top five high burden countries for tuberculosis and drug resistant TB. Among rifampicin sensitive new pulmonary TB (PTB), prevalence of isoniazid resistance is 8.3% (95%CI: 7.0-10.7) and resistance to fluoroquinolone is higher (11·1%, 95%CI: 7·8-14·3) than isoniazid resistance.. Five year retrospective data (2015-2019) of drug susceptibility testing (DST) for Mycobacterium tuberculosis isolates, performed using recommended phenotypic (pDST) and/or genotypic (gDST) methods was analyzed stratified by rifampicin results for isoniazid resistance profiles and associated levofloxacin and pyrazinamide resistance.. DST data was analyzed from 11045 TB patients. Isolates were tested using pDST (87%), gDST (92%) and both methods (79.5%). For both rifampicin and isoniazid, a significant difference (P < .001) was noted between resistance detected by pDST and gDST. Among isolates, tested by both methods (8787), 49% were resistant to rifampicin and 51.7% to isoniazid with discordance in resistant results of 15.8% for each, with 13.2% (570) of rifampicin resistance reported sensitive by pDST and 14.2% (660) of isoniazid resistance missed by gDST. Estimated isoniazid resistance among rifampicin sensitive new PTB, extrapulmonary TB and previously treated PTB was 9.8% (95%CI: 8.7-11.1), 6.8% (95%CI: 5.4-8.5) and 14.6% (95%CI: 11.8-17.9) respectively. Significant differences were reported between the genotypic profile of isoniazid resistance associated with rifampicin-resistant and sensitive isolates including detectable mutations (87% vs 71.6%), frequency of inhA (7.6% and 30.2%) and katG mutations (76.1% vs 41.2%) respectively. Among rifampicin resistant and sensitive isolates, a significantly higher level of resistance to levofloxacin and pyrazinamide was seen associated with isoniazid resistance.. There are risks and many challenges in implementing WHO recommended treatment for isoniazid resistant tuberculosis. The laboratory based surveillance can complement random surveys in country specific planning for TB diagnostics and appropriate treatment regimens.

Topics: Adolescent; Adult; Antitubercular Agents; Child; Child, Preschool; Drug Resistance, Bacterial; Epidemiological Monitoring; Female; Genotype; Humans; Infant; Isoniazid; Laboratories; Levofloxacin; Male; Microbial Sensitivity Tests; Pakistan; Phenotype; Pyrazinamide; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant; Young Adult

Tuberculosis (TB) is amongst the top five causes of death in women of childbearing age (15-≤44 years). Little is known about treatment of pregnant women with drug-resistant TB (DR-TB). Treatment for pregnant women remains challenging and more complex in DR-TB/HIV co-infection, where an evidence-based guide to clinical practice is limited. The study reviewed treatment and pregnancy outcomes and birth outcomes of their new-born in a cohort of pregnant women with DR-TB from three MDR-TB hospitals during 2010 and 2018.. Data were extracted from: TB register and patient clinic notes using a standardized case record form. Information on DR-TB treatment, pregnancy and Adverse Drug Events (ADEs) of twenty-six pregnant women treated with individualized second-line TB medications were captured. The frequency of favourable and adverse outcomes regarding disease and pregnancy were evaluated.. The mean age was 29 years (SD ±5.1), with the minimum and maximum age of 21 and 40 years, respectively. Eleven (42.3%) were previously treated with first-line TB drugs, 11 (42.3%) never treated before and 4 (15.4%) were previously treated for DR-TB. Of the 26 women, 15 (57.7%) had at least one ADE, but most had more than one ADE. Seventeen women were successfully treated, and 22 live births recorded. Live birth outcome was significantly associated with trimester of initiation of DR-TB treatment (p = 0.036). The proportion of live births for the pregnancy trimester when DR-TB treatment was initiated, were 60.0%, 90.9% and 100.0%, for first, second and third trimester, respectively.. DR-TB treatment should be delayed until after the first trimester. Routine pharmacovigilance surveillance integrated antenatal and delivery services with an integrated record of DR-TB treatment during pregnancy is recommended. Prospective studies using standardised case record forms for DR-TB treatment for pregnant women could provide more insight on the effect of DR-TB treatment on the birth outcome.

Topics: Adult; Antitubercular Agents; Cohort Studies; Coinfection; Drug Resistance, Bacterial; Female; HIV Infections; Humans; Middle Aged; Pregnancy; Pregnancy Outcome; Retrospective Studies; Rifampin; South Africa; Treatment Outcome; Tuberculosis; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Bacterial Proteins; Catalase; Ethambutol; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Streptomycin; Tuberculosis; Tuberculosis, Multidrug-Resistant; Turkey

Since the implementation of the Xpert MTB/RIF in Sao Paulo, Brazil, numerous Mycobacterium tuberculosis isolates presenting "rifampicin-resistant genotype with rifampicin-susceptible phenotype" were observed.. To evaluate the prevalence, rpoB mutations and transmission of M. tuberculosis resistant to rifampicin on Xpert MTB/RIF but susceptible on BACTEC MGIT system, in Sao Paulo state.. Patients' isolates with this pattern of rifampicin discordance, collected from 2014 to 2017, had their rpoB predominant rifampicin-resistance-determining region sequenced and were genotyped by IS6110 restriction fragment-length polymorphism.. The prevalence of rifampicin-discordant M. tuberculosis with genotypic resistance was 55.1% (156/283). Among the sequenced and genotyped isolates, 75.5% (111/147) were in clusters, largely associated with the type of rpoB mutation. Most isolates (98.6%; 72/73) harbouring the predominant mutation, His445Asn, were pooled into the two largest clusters, SP2ga (42/72; 58.3%) and SP5o (12/72; 16.7%). Ranking second, isolates carrying the silent mutation Phe433Phe were mostly (92.3%; 24/26) gathered into four groups of the family SP25.. These findings suggest that this unusual high rifampicin discrepancy proportion was greatly influenced by few actively circulating clusters. Further studies on many of the rpoB mutations identified in our setting are needed to elucidate their association with phenotypic rifampicin resistance.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antibiotics, Antitubercular; Bacterial Proteins; Brazil; Cross-Sectional Studies; DNA-Directed RNA Polymerases; Drug Resistance, Bacterial; Epidemics; Female; Genotype; Humans; Male; Middle Aged; Mutation; Mycobacterium tuberculosis; Phenotype; Rifampin; Tuberculosis, Multidrug-Resistant; Young Adult

Here we described phenotypical, molecular and epidemiological features of a highly rifampicin-resistant Mycobacterium tuberculosis strain emerging in Southern Brazil, that carries an uncommon insertion of 12 nucleotides at the codon 435 in the rpoB gene. Employing a whole-genome sequencing-based study on drug-resistant Mycobacterium tuberculosis strains, we identified this emergent strain in 16 (9.19%) from 174 rifampicin-resistant clinical strains, all of them belonging to LAM RD115 sublineage. Nine of these 16 strains were available to minimum inhibitory concentration determination and for all of them was found a high rifampicin-resistance level (≥to 32 mg/L). This high resistance level could be explained by structural changes into the RIF binding site of RNA polymerase caused by the insertions, and consequent low-affinity interaction with rifampicin complex confirmed through protein modeling and molecular docking simulations. Epidemiological investigation showed that most of the individuals (56.25%) infected by the studied strains were prison inmate individuals or that spent some time in prison. The phylogenomic approach revealed that strains carrying on insertion belonged to same genomic cluster, evidencing a communal transmission chain involving inmate individuals and community. We stress the importance of tuberculosis genomic surveillance and introduction of measures to interrupt Mycobacterium tuberculosis transmission chain in this region.

Topics: Antitubercular Agents; Bacterial Proteins; Brazil; DNA Mutational Analysis; DNA, Bacterial; Humans; Mutation; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant

The STREAM trial demonstrated that a 9-11-month "short" regimen had non-inferior efficacy and comparable safety to a 20+ month "long" regimen for the treatment of rifampicin-resistant tuberculosis. Imbalance in the components of the composite primary outcome merited further investigation.. Firstly, the STREAM primary outcomes were mapped to alternatives in current use, including WHO programmatic outcome definitions and other recently proposed modifications for programmatic or research purposes. Secondly, the outcomes were re-classified according to the likelihood that it was a Failure or Relapse (FoR) event on a 5-point Likert scale: Definite, Probable, Possible, Unlikely, and Highly Unlikely. Sensitivity analyses were employed to explore the impact of informative censoring. The protocol-defined modified intention-to-treat (MITT) analysis population was used for all analyses.. Cure on the short regimen ranged from 75.1 to 84.2% across five alternative outcomes. However, between-regimens results did not exceed 1.3% in favor of the long regimen (95% CI upper bound 10.1%), similar to the primary efficacy results from the trial. Considering only Definite or Probable FoR events, there was weak evidence of a higher risk of FoR in the short regimen, HR 2.19 (95%CI 0.90, 5.35), p = 0.076; considering only Definite FoR events, the evidence was stronger, HR 3.53 (95%CI 1.05, 11.87), p = 0.030. Cumulative number of grade 3-4 AEs was the strongest predictor of censoring. Considering a larger effect of informative censoring attenuated treatment differences, although 95% CI were very wide.. Five alternative outcome definitions gave similar overall results. The risk of failure or relapse (FoR) may be higher in the short regimen than in the long regimen, highlighting the importance of how loss to follow-up and other censoring is accounted for in analyses. The outcome of time to FoR should be considered as a primary outcome for future drug-sensitive and drug-resistant TB treatment trials, provided sensitivity analyses exploring the impact of departures from independent censoring are also included.

Topics: Antitubercular Agents; Humans; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant

Multidrug-resistant tuberculosis (MDR-TB) continues to be a global health problem. Data on rifampicin resistance MTB using Xpert- MTB/RIF assay in Ethiopia, particularly in the study area is limited. The aim of this study was to determine the frequency of MTB and rifampicin resistant-MTB among presumptive tuberculosis patients in Tigray, Northern Ethiopia.. A multicenter retrospective study was conducted among presumptive TB patients from five governmental hospitals and one comprehensive specialized teaching hospital in Tigray regional state. Records of sputum sample results of presumptive MTB patients with Xpert-MTB/RIF assay from January 2016 to December 2019 were investigated. Data extraction tool was used to collect data from registration books and analyzed using SPSS ver.21 statistical software. Statistical significance was set at p-value ≤ 0.05.. Of the 30,935 presumptive adult TB patients who have provided specimens for TB diagnosis from January 2016 to December 2019, 30,300 (98%) had complete data and were included in this study. More than half, 17,471 (57.7%) were males, and the age of the patients ranged from 18-112 years, with a median age of 40.65 (interquartile 29.4-56.5 years). Majority, 28,996 (95.7%) of the participants were treatment naïve, and 23,965 (79.1%) were with unknown HIV status. The overall frequency of MTB was 2,387 (7.9% (95% CI: 7.6-8.2%); of these, 215 (9% (95% CI: 7.9-10.2%) were rifampicin resistant-MTB. Age (18-29 years), HIV positive and previous TB treatment history were significantly associated with high MTB (p < 0.001), whereas gender (being female) was associated with low MTB (p < 0.001). Likewise, rifampicin resistant-MTB was more prevalent among relapse (p < 0.001) and failure cases (p = 0.025); while age group 30-39 years was significantly associated with lower frequency of rifampicin resistant-MTB (p = 0.008).. Frequency of MTB among tuberculosis presumptive patients was low; however, the problem of rifampicin resistant-MTB among the tuberculosis confirmed patients was high. The high frequency of MTB and RR-MTB among previously treated and HIV positive patients highlights the need for more efforts in TB treatment and monitoring program in the study area.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antibiotics, Antitubercular; Biological Assay; Cross-Sectional Studies; Drug Resistance, Multiple, Bacterial; Ethiopia; Female; Humans; Male; Middle Aged; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant; Young Adult

Randomized clinical trials represent the gold standard in therapeutic research. Nevertheless, observational cohorts of patients treated for multidrug-resistant TB (MDR-TB) or rifampin-resistant TB (RR-TB) also play an important role in generating evidence to guide drug-resistant TB care. Generally, summary exposure classifications (e.g., 'ever vs. never´, 'exposed at baseline´) have been used to characterize drug exposure in the absence of detailed longitudinal data on MDR-TB regimen changes. These summary classifications, along with an absence of data on covariates that change throughout the course of treatment, constrain researchers´ ability to answer the most relevant questions while accounting for known biases. In this paper, we highlight the importance of regimen changes in improving inference from observational studies of longer MDR-TB treatment regimens, and offer an overview of the data and analytic strategies required to do so.

Topics: Antitubercular Agents; Clinical Protocols; Cohort Studies; Humans; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant

Rapid diagnostics, newer drugs, repurposed medications, and shorter regimens have radically altered the landscape for treating rifampicin-resistant TB (RR-TB) and multidrug-resistant TB (MDR-TB). There are multiple ongoing clinical trials aiming to build a robust evidence base to guide RR/MDR-TB treatment, and both observational studies and programmatic data have contributed to advancing the treatment field. In December 2019, the WHO issued their second 'Rapid Communication´ related to RR-TB management. This reiterated their prior recommendation that a majority of people with RR/MDR-TB receive all-oral treatment regimens, and now allow for specific shorter duration regimens to be used programmatically as well. Many TB programs need clinical advice as they seek to roll out such regimens in their specific setting. In this Perspective, we highlight our early experiences and lessons learned from working with National TB Programs, adult and pediatric clinicians and civil society, in optimizing treatment of RR/MDR-TB, using shorter, highly-effective, oral regimens for the majority of people with RR/MDR-TB.

Topics: Adult; Antitubercular Agents; Child; Clinical Protocols; Humans; Rifampin; Time Factors; Tuberculosis, Multidrug-Resistant

Topics: Humans; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

India has the highest number of TB (27%) and MDR/RR-TB (24%) cases among the notified TB patients. Xpert MTB/ RIF assay is a fully automated cartridge-based real-time PCR to detect MTB and resistance to rifampicin within two hours using three specific primers and five unique molecular probes to target the rpoB gene. This study was done to detect RR-TB cases and frequency of missing probes, which target mutations in rpoB gene, in the different groups of study population in Sirmaur district of Himachal Pradesh.. All, pulmonary and extrapulmonary specimens, were processed for AFB microscopy and Xpert MTB/RIF assay to diagnose TB and RR-TB.. Xpert detected MTBC in 721 patients. Using AFB microscopy, only 284 samples were positive. Of these MTB positive patients, 671 had pulmonary TB and 50 were EPTB cases. Resistance to RIF was detected in 31 (4.29%) cases of which resistance in presumptive tuberculosis group and presumptive drug resistant tuberculosis was 1.51% and 9.30% respectively. Twentyeight (4.17%) PTB cases and three (6%) EP-TB cases were resistant to RIF. The frequency of probe E was highest (77.41%) and mutation combination of probes C and D and E and D was 3.22%.. Drug resistance in the MTBC is mainly conferred through point mutations in specific gene targets in the bacterial genome. Molecular assays like Genexpert gives rapid diagnosis and Rifampicin resistance. This study helps to provide baseline data of mutations with in the 81 bp of rpoB gene and stresses the need to further evaluate the mutation patterns in this part of the country.

Topics: Drug Resistance, Bacterial; Humans; India; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

it is unclear what the optimal treatment regimen for previously treated patients with rifampicin-susceptible isoniazid resistant tuberculosis should be. Conflicting evidence exists as to the effectiveness of the WHO standardized category II regimen in these patients. The objectives were to compare treatment outcomes between previously treated rifampicin-susceptible pulmonary tuberculosis patients with and without isoniazid resistance using the category II regimen and determine factors associated with an unfavourable outcome in those with isoniazid resistance in four regions of Cameroon.. we conducted a retrospective review of all bacteriologically confirmed previously treated rifampicin-susceptible patients with and without isoniazid resistance registered in four regions of Cameroon from January 2012 to March 2015.. a total of 753 patients with a mean age of 38 ± 12 years including 498(66%) males were registered. Forty seven of the 753 had isoniazid-resistant TB, giving a prevalence of 6.2% (95% CI: 4.7-8.2). Treatment outcomes could only be ascertained for 733 patients as 20 (2.7%) were transferred out to other regions. Twenty-nine percent of patients with isoniazid resistance as against 21% of isoniazid susceptible patients had an unfavourable outcome (p = 0.32). In a multivariate logistic regression analysis, only HIV infection was significantly associated with an unfavourable outcome in isoniazid-resistant patients (p = 0.02).. treatment outcomes using WHO category II regimen in previously treated rifampicin -susceptible pulmonary tuberculosis patients with and without isoniazid resistance in four regions of Cameroon are similar. HIV infection is an independent risk factor for an unfavourable outcome in patients with rifampicin-susceptible isoniazid-resistant disease treated with this regimen.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antitubercular Agents; Cameroon; Child; Child, Preschool; Female; HIV Infections; Humans; Isoniazid; Male; Middle Aged; Retrospective Studies; Rifampin; Risk Factors; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

Tuberculosis is one of the major causes of death globally. The problems become even more complicated with the rise in prevalence of multidrug resistant tuberculosis (MDR-TB). Many diseases have been reported to occur with tuberculosis making it more difficult to manage. Candida spp., which are yeast-like fungi and a constituent of normal flora in humans, are notoriously reported to be one of the most common opportunistic nosocomial infections. This study aimed to measure the proportion of presumptive MDR-TB patients colonized with Candida spp. and to characterize its susceptibility against azole group antifungal agents.. Sputum from presumptive MDR-TB patients were collected and examined for the presence of Mycobacterium tuberculosis and its rifampicin resistant status using GeneXpert. It was further cultured on Sabouroud's Dextrose Agar (SDA) to isolate the Candida spp. The Candida species were determined using HiCrome™ Candidal Differential Agar. Antifungal susceptibility was tested using microbroth dilution methods. Checkerboard microdilution assays were performed to measure the interaction between rifampicin and fluconazole to C. albicans.. There were 355 presumptive MDR-TB patients enrolled. A total of 101 (28.4%) patients were confirmed to have M. tuberculosis. There were 113 (31.8%) sputum positive for Candida spp., which corresponded to 149 Candida spp. isolates. Candida albicans was the most frequent (53.7%) species isolated from all patients. The susceptibility of Candida spp. against fluconazole, itraconazole, and ketoconazole were 38.3%, 1.3%, and 10.7% respectively. There was significant association between rifampicin exposure history and susceptibility of Candida albicans against fluconazole (Odds Ratio: 9.96; 95% CI: 1.83-54.19; p <0.01), but not for ketoconazole and itraconazole. The checkerboard microdilution assays showed that rifampicin decreased the fungicidal activity of fluconazole to C. albicans in a dose-dependent manner.. There was high frequency of azole resistant Candida spp. isolates colonizing the respiratory tract of presumptive MDR-TB patients. This presence might indicate the association of chronic exposure to rifampicin, the main drug for tuberculosis therapy, with the induction of azole resistance.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antifungal Agents; Antitubercular Agents; Candida; Candidiasis; Child; Drug Interactions; Drug Resistance, Multiple, Fungal; Female; Fluconazole; Humans; Itraconazole; Ketoconazole; Male; Microbial Sensitivity Tests; Middle Aged; Rifampin; Species Specificity; Tuberculosis, Multidrug-Resistant; Young Adult

Introduction: The Xpert MTB/RIF™ is a rapid molecular test that diagnoses tuberculosis and rifampin resistance. Since 2010, it is recommended by the World Health Organization (WHO) and although it was introduced in Colombia since 2012, the results of its implementation are unknown.\ Objective: To describe the coverage and fidelity in the implementation of the Xpert MTB/RIF™ in patients with pulmonary tuberculosis in a city with a high burden for the disease in Colombia.\ Materials and methods: We conducted a retrospective, descriptive study of cases from a tuberculosis program in Cali between 2013 and 2019. We estimated the coverage as the total number of tests used compared to the cases registered in the program and the fidelity based on international Xpert MTB/RIF™ implementation protocols. We performed a multivariate analysis of multiple correspondences between the test and the sociodemographic variables.\ Results: We included 6,328 patients with pulmonary tuberculosis of whom 181 were drugresistant. The Xpert MTB/RIF™ coverage was 10,3% (n=655) with an annual variation between 0.2% and 23%. Loyalty among the highest risk groups of MDR-TB was 46.8%. The use of the test was related to being an Afro-Colombian man between 41 and 60 years of age.\ Conclusions: The coverage of the Xpert MTB/RIF in Cali is low and its use does not follow the recommended prioritization for its implementation. Implementation strategies are required for its proper use to contribute to the goal of ending tuberculosis.. Introducción. La prueba Xpert MTB/RIF™ es una prueba molecular rápida para el diagnóstico de la tuberculosis y la resistencia a la rifampicina. Desde el 2010 es la recomendada por la Organización Mundial de la Salud (OMS) y, aunque fue introducida en Colombia en el 2012, se desconocen los resultados de su uso. Objetivo. Describir la cobertura y la fidelidad en el uso de la prueba Xpert MTB/RIF™ en pacientes con tuberculosis pulmonar en una ciudad con alta carga de la enfermedad en Colombia. Materiales y métodos. Se hizo un estudio retrospectivo descriptivo de casos del programa de tuberculosis en Cali entre el 2013 y el 2019. La cobertura se estimó como el total de pruebas empleadas en los casos registrados en el programa. La fidelidad se midió con base en los protocolos internacionales de uso de la Xpert MTB/RIF™. Además, se hizo un análisis de correspondencias múltiples entre la prueba y las variables sociodemográficas. Resultados. Se incluyeron 6.328 pacientes con tuberculosis pulmonar, de los cuales 181 eran resistentes a los fármacos. La cobertura total de la Xpert MTB/RIF™ durante el periodo de estudio fue de 10,3 % (n=655), con una variación anual entre 0,2 y 23 %. La fidelidad fue de 46,8 % para los grupos de mayor riesgo de tuberculosis multirresistente (TB-MDR). El uso de la prueba se relacionó con la condición de ser hombre, afrocolombiano, y tener entre 41 y 60 años de edad. Conclusiones. La cobertura de la prueba Xpert MTB/RIF™ en Cali es baja y su uso no responde a la priorización recomendada para su implementación. Se requieren estrategias para promover su uso adecuado, de manera que contribuya a la meta de poner fin a la tuberculosis.

Topics: Adolescent; Adult; Aged; Antibiotics, Antitubercular; Child; Child, Preschool; Colombia; Drug Resistance, Bacterial; Female; Humans; Infant; Infant, Newborn; Insurance Coverage; Male; Microbial Sensitivity Tests; Middle Aged; Multivariate Analysis; Mycobacterium tuberculosis; Real-Time Polymerase Chain Reaction; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

There are few data on the on the care experiences of pregnant women with rifampicin-resistant TB.. To describe the treatment journeys of pregnant women with RR-TB-including how their care experiences shape their identities-and identify areas in which tailored interventions are needed.. In this qualitative study in-depth interviews were conducted among a convenience sample from a population of pregnant women receiving treatment for RR-TB. This paper follows COREQ guidelines. A thematic network analysis using an inductive approach was performed to analyze the interview transcripts and notes. The analysis was iterative and a coding system developed which focused on the care experiences of the women and how these experiences affected their perceptions of themselves, their children, and the health care system in which treatment was received.. Seventeen women were interviewed. The women described multiple challenges in their treatment journeys which required them to demonstrate sustained resilience (i.e. to "be brave"). Care experiences required them to negotiate seemingly contradictory identities as both new mothers-"givers of life"-and RR-TB patients facing a complicated and potentially deadly disease. In terms of their "pregnancy identity" and "RR-TB patient identity" that emerged as part of their care experiences, four key themes were identified that appeared to have elements that were contradictory to one another (contradictory areas). These included: 1) the experience of physical symptoms or changes; 2) the experience of the "mothering" and "patient" roles; 3) the experience of the care they received for their pregnancy and their RR-TB; and 4) the experience of community engagement. There were also three areas that overlapped with both roles and during which identity was negotiated/reinforced and they included: 1) faith; 2) socioeconomic issues; and 3) long-term concerns over the child's health. At times, the health care system exacerbated these challenges as the women were not given the support they needed by health care providers who were ill-informed or angry and treated the women in a discriminatory fashion. Left to negotiate this confusing time period, the women turned to faith, their own mothers, and the fathers of their unborn children.. The care experiences of the women who participated in this study highlight several gaps in the current health care system that must be better addressed in both TB and perinatal services in order to improve the therapeutic journeys for pregnant women with RR-TB and their children. Suggestions for optimizing care include the provision of integrated services, including specialized counseling as well as training for health care providers; engagement of peer support networks; provision of socioeconomic support; long-term medical care/follow-up for children born to women who were treated for RR-TB; and inclusion of faith-based services in the provision of care.

Topics: Adult; Antitubercular Agents; Courage; Female; Humans; Infant; Mothers; Mycobacterium tuberculosis; Patient Satisfaction; Pregnancy; Pregnant Women; Qualitative Research; Rifampin; Social Identification; Social Support; South Africa; Surveys and Questionnaires; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

There is a need for an affordable, easy, high-sensitivity test usable at the peripheral health facility for diagnosis of drug-resistant (DR) tuberculosis (TB) to interrupt disease transmission. Nucleic acid amplification tests (NAATs) for early detection of DR-TB are ideal to bring testing near to the patient. Truenat. Consecutive patients aged 18-65 yr, with symptoms suggestive of TB and with a history of previous treatment, reporting to the National TB Elimination Programme (NTEP) clinics under four national institutes, namely AIIMS (All India Institute of Medical Sciences, New Delhi), NITRD (National Institute of Tuberculosis and Respiratory Diseases, New Delhi), NIRT (National Institute for Research in Tuberculosis, Chennai) and ICMR-National JALMA Institute for Leprosy and other Mycobacterial Diseases, Agra, were included in the study. Two sputum samples (one spot and one morning) were collected from each patient, after obtaining informed written consent. The samples were subjected to smear, GeneXpert and MGIT 960 culture (and drug susceptibility testing to RIF) (surrogate for MDR-TB) to serve as reference tests. The samples were coded to ensure blinding and subjected to Truenat MTB-RIF. Truenat MTB-RIF Version 1.5 was used for testing 1084 samples for RIF resistance, while Version 2.0 was used to test another 1201 samples.. Truenat MTB-RIF Version 1.5 in comparison with comprehensive laboratory reference standards yielded sensitivity and specificity of 76.2 and 94.7 per cent, respectively for the detection of RIF resistance in 1084 samples, collected across four sites. Based on the analysis of discordant samples, Version 2.0 of Truenat was developed by the manufacturer and this was further tested on additional 1201 samples, yielding a sensitivity of 87.5 per cent and specificity of 99.5 per cent.. Multicentric trial of Truenat

Topics: Adolescent; Adult; Aged; Humans; India; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

Heteroresistant Mycobacterium tuberculosis (MTB) is defined as a group of drug-susceptible and resistant bacteria in a single clinical specimen from tuberculosis (TB) patients. Heteroresistance of MTB is considered a preliminary stage to full resistance. The present study aimed to determine the heteroresistance in Mycobacterium tuberculosis in Tabuk province, in the north of the Kingdom of Saudi Arabia.. GenoType MTBDRplus assay was used to determine mutations associated with isoniazid and rifampicin resistance.. A total number of 46 confirmed M. tuberculosis positive sputum samples were scanned for heteroresistance. The present study revealed 3 (6.5%) heteroresistant mutations to either rpoB gene alone, 2 (4.4%) to rpoB and 1 (2.2%) to inhA genes.. The detection of heteroresistant mutations could guide the initiation of an appropriate regimen of treatment.

Topics: Antitubercular Agents; Cross-Sectional Studies; Drug Resistance, Multiple, Bacterial; Genotype; Humans; Isoniazid; Mutation; Mycobacterium tuberculosis; Rifampin; Saudi Arabia; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

We assessed multidrug-resistant tuberculosis (MDR-TB) cases and their household contacts (HHCs) to inform the development of an interventional clinical trial.. We conducted a cross-sectional study of adult MDR-TB cases and their HHCs in 8 countries with high TB burdens. HHCs underwent symptom screenings, chest radiographies, sputum TB bacteriologies, TB infection (TBI) testing (tuberculin skin test [TST] and interferon gamma release assay [IGRA]), and human immunodeficiency virus (HIV) testing.. From October 2015 to April 2016, 1016 HHCs from 284 MDR-TB cases were enrolled. At diagnosis, 69% of MDR-TB cases were positive for acid-fast bacilli sputum smears and 43% had cavitary disease; at study entry, 35% remained smear positive after a median MDR-TB treatment duration of 8.8 weeks. There were 9 HHCs that were diagnosed with TB prior to entry and excluded. Of the remaining 1007 HHCs, 41% were male and the median age was 25 years. There were 121 (12%) HHCs that had new cases of TB identified: 17 (2%) were confirmed, 33 (3%) probable, and 71 (7%) possible TB cases. The TBI prevalence (defined as either TST or IGRA positivity) was 72% and varied by age, test used, and country. Of 1007 HHCs, 775 (77%) were considered high-risk per these mutually exclusive groups: 102 (10%) were aged <5 years; 63 (6%) were aged ≥5 and were infected with HIV; and 610 (61%) were aged ≥5 years, were negative for HIV or had an unknown HIV status, and were TBI positive. Only 21 (2%) HHCs were on preventive therapy.. The majority of HHCs in these high-burden countries were at high risk of TB disease and infection, yet few were receiving routine preventive therapy. Trials of novel, preventive therapies are urgently needed to inform treatment policy and practice.

Topics: Adult; Child, Preschool; Cross-Sectional Studies; Family Characteristics; Feasibility Studies; Female; Humans; Male; Rifampin; Tuberculin Test; Tuberculosis; Tuberculosis, Multidrug-Resistant

Tuberculosis (TB) is an infection disease caused by Mycobacterium tuberculosis (Mtb) bacteria. One of the main causes of mortality from TB is the problem of Mtb resistance to known drugs.. The goal of this work is to identify potent small molecule anti-TB agents by machine learning, synthesis and biological evaluation.. The On-line Chemical Database and Modeling Environment (OCHEM) was used to build predictive machine learning models. Seven compounds were synthesized and tested in vitro for their antitubercular activity against H37Rv and resistant Mtb strains.. A set of predictive models was built with OCHEM based on a set of previously synthesized isoniazid (INH) derivatives containing a thiazole core and tested against Mtb. The predictive ability of the models was tested by a 5-fold cross-validation, and resulted in balanced accuracies (BA) of 61-78% for the binary classifiers. Test set validation showed that the models could be instrumental in predicting anti- TB activity with a reasonable accuracy (with BA = 67-79 %) within the applicability domain. Seven designed compounds were synthesized and demonstrated activity against both the H37Rv and multidrugresistant (MDR) Mtb strains resistant to rifampicin and isoniazid. According to the acute toxicity evaluation in Daphnia magna neonates, six compounds were classified as moderately toxic (LD50 in the range of 10-100 mg/L) and one as practically harmless (LD50 in the range of 100-1000 mg/L).. The newly identified compounds may represent a starting point for further development of therapies against Mtb. The developed models are available online at OCHEM http://ochem.eu/article/11 1066 and can be used to virtually screen for potential compounds with anti-TB activity.

Topics: Animals; Antitubercular Agents; Daphnia; Datasets as Topic; Drug Design; Humans; Isoniazid; Machine Learning; Microbial Sensitivity Tests; Models, Chemical; Mycobacterium tuberculosis; Rifampin; Toxicity Tests, Acute; Tuberculosis, Multidrug-Resistant

Monoresistance to rifamycins necessitates longer and more toxic regimens for tuberculosis (TB). We examined characteristics and mortality associated with rifampin-monoresistant (RMR) TB in the United States.. We analyzed Mycobacterium tuberculosis culture-positive cases reported to the National TB Surveillance System (excluding California) between 1998 and 2014. We defined RMR TB found on initial drug susceptibility testing and possible acquired rifampin-resistant (ARR) TB. We assessed temporal trends in RMR TB. For both classifications of rifampin resistance, we calculated adjusted risk ratios (adjRRs) and 95% confidence intervals (CIs) for characteristics associated with mortality when compared with drug-susceptible TB in multivariable models using backward selection.. Of 180 329 TB cases, 126 431 (70%) were eligible for analysis, with 359 (0.28%) of eligible cases reported as RMR. The percentage of RMR TB cases with HIV declined 4% annually between 1998 and 2014. Persons with HIV and prior TB were more likely to have RMR TB (adjRR, 25.9; 95% CI, 17.6-38.1), as were persons with HIV and no prior TB (adjRR, 3.1; 95% CI, 2.4-4.1) vs those without either characteristic, controlling for other statistically significant variables. RMR cases had greater mortality (adjRR, 1.4; 95% CI, 1.04-1.8), controlling for HIV and other variables. Persons with HIV had greater risk of ARR than persons without HIV (adjRR, 9.6; 95% CI, 6.9-13.3), and ARR was also associated with increased mortality, controlling for HIV and other variables.. All forms of rifampin resistance were positively associated with HIV infection and increased mortality.

Topics: Antitubercular Agents; HIV Infections; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant; United States

Tuberculosis (TB) is one of the deadliest infectious diseases in humankind history. Although, drug sensible TB is slowly decreasing, at present the rise of TB cases produced by multidrug-resistant (MDR) and extensively drug-resistant strains is a big challenge. Thus, looking for new therapeutic options against these MDR strains is mandatory. In the present work, we studied, in BALB/c mice infected with MDR strain, the therapeutic effect of supra-pharmacological doses of the conventional primary antibiotics rifampicin and isoniazid (administrated by gavage or intratracheal routes), in combination with recombinant human hepatocyte growth factor (HGF). This high dose of antibiotics administered for 3 months, overcome the resistant threshold of the MDR strain producing a significant reduction of pulmonary bacillary loads but induced liver damage, which was totally prevented by the administration of HGF. To address the long-term efficiency of this combined treatment, groups of animals after 1 month of treatment termination were immunosuppressed by glucocorticoid administration and, after 1 month, mice were euthanized, and the bacillary load was determined in lungs. In comparison with animals treated only with a high dose of antibiotics, animals that received the combined treatment showed significantly lower bacterial burdens. Thus, treatment of MDR-TB with very high doses of primary antibiotics particularly administrated by aerial route can produce a very good therapeutic effect, and its hepatic toxicity can be prevented by the administration of HGF, becoming in a new treatment modality for MDR-TB.

Topics: Animals; Antibiotics, Antitubercular; Antioxidants; Chemical and Drug Induced Liver Injury; Drug Therapy, Combination; Hepatocyte Growth Factor; Humans; Isoniazid; Liver; Male; Mice; Mice, Inbred BALB C; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

The development of an effective antitubercular agent is a challenge due to the complex nature of tuberculosis. Herein, we report the synthesis and evaluation of α-aminoacyl amides as antitubercular agents. The systematic medicinal chemistry approach led to identification of optimal substitutions required for the activity. Compound 11l was identified as antitubercular lead with drug like properties. Further, 11l selectively inhibited M. tuberculosis H37Rv with MIC value of 0.78 μM and was found to be non-toxic to CHOK1 cells. The lead compound inhibited multidrug resistant and Pre-Extensively drug resistant strains of Mycobacterium at 2 μg/mL and 8 μg/mL respectively.

Topics: Amides; Animals; Antitubercular Agents; Cell Line; Chemistry, Pharmaceutical; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Tuberculosis, Multidrug-Resistant

In the present study, a series of substituted 1,3,4-thiadiazole derivatives 4(a-o), 5(a-m) and 6(a-j) were synthesized and characterized by IR,

Topics: Animals; Antitubercular Agents; Chlorocebus aethiops; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Nitrophenols; Pyridines; Structure-Activity Relationship; Thiadiazoles; Tuberculosis, Multidrug-Resistant; Vero Cells

The dormant and resistant form of Mycobacterium tuberculosis presents a challenge in developing new anti-tubercular drugs. Herein, we report the synthesis and evaluation of trisubstituted thiazoles as antituberculosis agents. The SAR study has identified a requirement of hydrophobic substituent at C2, ester functionality at C4, and various groups with hydrogen bond acceptor character at C5 of thiazole scaffold. This has led to the identification of 13h and 13p as lead compounds. These compounds inhibited the dormant Mycobacterium tuberculosis H37Ra strain and M. tuberculosis H37Rv selectively. Importantly, 13h and 13p were non-toxic to CHO cells. The 13p showed activity against multidrug-resistant tuberculosis isolates.

Topics: Antitubercular Agents; Dose-Response Relationship, Drug; Humans; Microbial Sensitivity Tests; Molecular Structure; Mycobacterium tuberculosis; Structure-Activity Relationship; Thiazoles; Tuberculosis, Multidrug-Resistant

A population pharmacokinetic (PopPK) model for pretomanid was developed using data from 14 studies in the pretomanid development program: six phase 1 studies, six phase 2 studies, and two phase 3 studies. The final analysis data set contained 17,725 observations from 1,054 subjects, including healthy subjects and subjects with drug-sensitive, multidrug-resistant, or extensively drug-resistant pulmonary tuberculosis dosed pretomanid in monotherapy or combination therapy for up to 6 months. Pretomanid pharmacokinetic behavior was described by a one-compartment model that at a given dose was linear in its absorption and clearance processes but where the rate of absorption and extent of bioavailability changed with dose. Clearance and volume of distribution scaled allometrically with weight. Apparent clearance in females was 18% less than in males. Among HIV-positive subjects, absent the effect of CYP3A4-inducing antiretrovirals, apparent clearance was 6% higher. Some effects of total bilirubin and albumin were found, but the impacts on exposure were small. Bioavailability in the fasted condition was about half that in the fed condition. Relative bioavailability decreased with increasing dose in the fasted condition, but not for doses of ≤200 mg in the fed condition. HIV-positive subjects taking efavirenz and lopinavir/ritonavir had exposures that were reduced by 46 and 17%, respectively. There was little evidence for noteworthy effects of regimen partners on pretomanid. Standard diagnostics indicated that the model described the voluminous, diverse data well, so that the model could be used to generate exposure metrics for exposure/response analyses to be reported elsewhere.

Topics: Antitubercular Agents; Biological Availability; Clinical Trials as Topic; Extensively Drug-Resistant Tuberculosis; Female; HIV Infections; Humans; Lopinavir; Male; Nitroimidazoles; Rifampin; Ritonavir; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Tuberculosis (TB) is continuing to be a important public health problem in the undeveloped countries. Drug sensitivity rate should be monitored for the effective treatment and control in the TB. The aim of this study was to determine the rate of resistance to first line TB drugs in the Mycobacterium tuberculosis complex isolates.. During one-year period, M. tuberculosis complex was isolated in the 1193 samples from 974 patients in the Mycobacterial Laboratory of Yedikule Chest Diseases and Chest Surgery Education and Research Hospital, Istanbul, Turkey. The majority of samples isolated in the M. tuberculosis complex were sputum (n= 897, 92.1%). Anti-TB drug susceptibility testing was performed with Mycobacterium Growth Indicator Tube 960 system.. Two hundred and sixty isolat (26.7%) were resistant to at least one of the four first-line anti-TB drugs tested. One hundred ninety seven isolates were resistances to isoniazid (20.2%); 82 to rifampin (8.4%), 63 to ethambutol (6.5%) and 140 to streptomycin (14.4%). Of the 197 isoniazid-resistant isolates, 89 (45.2%) isolates was only isoniazid-resistance, only rifampin-resistance were found 15.9% (n= 13), ethambutol 7.9% (n= 5) and streptomycin 30.7% (n= 43). There were 48 (4.9%) isolates with two drugresistance, 22 (2.3%) isolates with three drug-resistance, and 42 (4.3%) isolates with four drug-resistance. The multidrug resistance rate was 7% (68 of 974). There was no relationship with between the frequency of TB drug resistance and gender or age. The isoniazid--resistance and streptomycin-resistance were seen to tend to increase if together considered the results of this study with outcomes of previously reported studies from Turkey in the 1998-2003, 2004-2007 and 2008-2010 years.. Monitoring of drug susceptibility test results can contribute to the management of TB treatment and increase treatment success. Isoniazid-resistance and streptomycin-resistance tend to increase in Turkey. Further clinical studies are needed to investigate regional and global factors affecting the development of resistance to first-line TB drugs.

Topics: Adolescent; Adult; Antitubercular Agents; Ethambutol; Female; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Public Health; Rifampin; Sputum; Streptomycin; Tertiary Care Centers; Tuberculosis, Multidrug-Resistant; Turkey; Young Adult

To compare the diagnostic performance of the GenoType MRBDRplus assay with the gold standard phenotypic drug susceptibility testing in the detection of drug resistance among culture isolates obtained from patients in Karachi, Pakistan.. Mycobacterium tuberculosis isolates were obtained from 96 consecutive tuberculosis patients found to have resistance to isoniazid from two health centers in Karachi (January-November 2017). Isolates were tested for drug resistance against rifampin and isoniazid using the MTBDRplus assay. Results were compared with conventional drug-susceptibility testing and the frequency of specific mutations were reported.. The MTBDRplus assay had a sensitivity for rifampin resistance of 98.8% (95% CI: 93.4-100) and for isoniazid resistance of 90.6% (95% CI: 83.0-95.6). The MTBDRplus assay showed mutations in rpoB in 81 of the 96 (84.4%) isolates. Of the 87 isolates showing resistance to isoniazid via the MTBDRplus assay, 71 (74.0%) isolates had mutations in the katG gene only, 15 (15.6%) isolates had mutations in the inhA promoter region, and 1 (1.0%) showed mutations in both genes.. The GenoType MTBDRplus assay in Pakistan can identify subgroups at high-risk of having isolates with mutations in the katG and/or inhA genes. Understanding the local burden of these mutations have implications for local diagnostic and treatment guidelines.

Topics: Antitubercular Agents; Bacterial Proteins; DNA-Directed RNA Polymerases; Genotype; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Pakistan; Rifampin; Tuberculosis, Multidrug-Resistant

Isoniazid resistant tuberculosis is the most prevalent type of resistance in Swaziland and over two-thirds of the isoniazid resistant tuberculosis patients are tuberculosis and human immunodeficiency virus co-infected. The study aimed to determine risk factors associated with isoniazid resistant tuberculosis among human immunodeficiency virus positive patients in Swaziland.. This was a case-control study conducted in nine healthcare facilities across Swaziland. Cases were patients with isoniazid resistant tuberculosis (including 78 patients with isoniazid mono-resistant tuberculosis, 42 with polydrug-resistant tuberculosis, and 77 with multidrug-resistant tuberculosis). Controls were presumed drug-susceptible tuberculosis patients (n = 203). Multinomial logistic regression was used to determine related factors.. The median time lag from diagnosis to tuberculosis treatment initiation was 50 days for isoniazid mono or poly drug-resistant tuberculosis, 17 days for multidrug-resistant tuberculosis compared to 1 day for drug-susceptible tuberculosis patients. History of previous tuberculosis treatment was positively associated with either isoniazid mono or poly drug-resistant tuberculosis (OR = 7.91, 95% CI: 4.14-15.11) and multidrug-resistant tuberculosis (OR = 12.20, 95% CI: 6.07-24.54). Isoniazid mono or poly resistant tuberculosis patients were more likely to be from rural areas (OR = 2.05, 95% CI: 1.23-3.32) and current heavy alcohol drinkers compared to the drug-susceptible tuberculosis group. Multi drug-resistant tuberculosis patients were more likely to be non-adherent to tuberculosis treatment compared to drug-susceptible tuberculosis group (OR = 3.01, 95% CI: 1.56-5.82).. To prevent and control isoniazid resistant tuberculosis among HIV-positive patients in Swaziland, the tuberculosis program should strengthen the use of rapid diagnostic tests, detect resistance early, promptly initiate supervised tuberculosis treatment and decentralize quality tuberculosis services to the rural areas. Adherence to tuberculosis treatment should be improved.

Topics: Adult; AIDS-Related Opportunistic Infections; Antitubercular Agents; Case-Control Studies; Eswatini; Female; HIV Infections; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Rifampin; Risk Factors; Socioeconomic Factors; Tuberculosis; Tuberculosis, Multidrug-Resistant

The gold standard of antituberculosis susceptibility testing is based on culture method which takes weeks. Rapid detection of resistance to isoniazid (INH) and rifampin (RIF) to avoid inappropriate regimens and to prevent transmission of resistant strains are important. A membrane array (BluePoint MTBDR) was developed to identify Mycobacterium tuberculosis complex (MTBC) and the genetic mutations responsible for resistance to RIF and INH. We aimed to evaluate the performance of this array for diagnosing drug-resistant MTBC. A total of 261 acid-fast bacilli positive sputum specimens, 1025 positive mycobacteria growth indicator tube (MGIT) cultures and 544 clinical isolates were analyzed. Antituberculosis susceptibility testing was the gold standard and was performed on MTBC isolated from positive MGIT cultures and on 544 clinical isolates. The sensitivity and specificity of the array to detect MTBC were 62.2% and 88.1% for sputum specimens, 100% and 97.9% for MGIT cultures. For detection of drug-resistant MTBC in positive MGIT tubes, the sensitivities of the array were 100% for RIF and 97.1% for INH, while the specificities were 99.7% and 100%, respectively. Interestingly, we noticed four genotypically RIF-resistant but phenotypically RIF-susceptible isolates and eight genotypically INH resistant but phenotypically INH-susceptible isolates. Comparing with conventional culture methods for species identification and drug susceptibility testing, the BluePoint MTBDR assay demonstrated to be a rapid test with high sensitivity and specificity to identify MTBC and to detect isoniazid and rifampin resistance when it is applied to broth culture specimens and clinical isolates.

Topics: Antitubercular Agents; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Polymerase Chain Reaction; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant

Diagnosis of extra pulmonary tuberculosis (EPTB) is challenging due to its atypical clinical presentation and frequently results in a delay or deprivation of treatment. Apart from rapid case detection, early determination of MDR status is imperative in such situations. The commercially available Geno Type MTBDRplus assay version 2.0 (Hain Lifescience, Nehren, Germany) detects both the presence of Mycobacterium tuberculosis (MTB) complex as well as the presence of INH and Rifampcin resistance. We aim to evaluate the role of this test in diagnosis and detection of resistance by comparing its performance against gold standard i.e. culture and against the composite reference standards (CRS) in the diagnosis of EPTB.. The data of 130 EPTB samples processed form January 2014 till May 2017 at Poona Hospital and Research centre were selected for the study. All the samples were processed for Ziehl-Neelsen stain, Geno Type MTBDRplus assay (LPA) and liquid automated culture (BacT/Alert) simultaneously. Geno Type MTBDRplus assay (LPA) was performed directly on the samples. The 24 samples giving positive results on LPA and grown M. tuberculosis on culture were subjected to anti mycobacterial susceptibility testing for 1st line anti-tubercular drugs by BACTEC MGIT 320 system.. Out of 130 samples, 7 samples grew atypical mycobacterium and all the 7 samples turned negative on Line Probe Assay. Direct LPA on processed samples yielded 48/130 (36.9%) positivity. Geno Type MTBDRplus assay was positive for M. tuberculosis in (72.09%) 31/43 culture positive cases and (21%) 17/80 of culture negative cases. Geno Type MTBDRplus assay sensitivity and specificity results were assessed in comparison to CRS made up of culture results and clinical, radiological and histological findings. The overall sensitivity of Geno Type MTBDRplus assay was 45.19% (47/104) and specificity was 94.73 (18/19). Out of 24 samples which were compared for results between LPA and culture, Geno Type MTBDRplus assay accurately identified 3 of 3 of Rifampcin resistant strains and 20 of 21 Rifampcin sensitive strains. Geno Type MTBDRplus assay identified 4 of 4 INH resistant strains and 19 of 20 INH sensitive strains and MDR was obtained for 3 of 3 strains.. Geno Type MTBDRplus assay can give early diagnosis and sensitivity for both INH and Rifampcin in extra pulmonary samples. More number of studies is further required to establish Geno Type MTBDRplus assay as an important tool for obtaining diagnosis and resistance to first line drugs in extra pulmonary samples.

Topics: Adult; Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Early Diagnosis; Female; Genotyping Techniques; Humans; India; Male; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Sensitivity and Specificity; Tertiary Care Centers; Tuberculosis, Multidrug-Resistant; Young Adult

Multi-drug-resistant TB (MDR-TB) has become a significant public health problem and an obstacle to effective TB control. Rapid diagnostic tests for anti tubercular drugs sensitivity have significantly reduced total time in initiation of treatment. Still there is a significant gap between MDR diagnosis and start of category IV treatment. Delay in establishing the diagnosis may cause disease progression, transmission, lost to follow up and death. This study was planned to assess the actual delay from day one of sputum examination to the day of initiation of category IV in operational settings.. MDR-TB suspected patients attending the Respiratory medicine department, JLNMC, Ajmer from June-15 to July-16 were followed from sputum examination to sample deposition for drug sensitivity testing (LPA/CBNAAT) to MDR detection to category IV initiation, for assessment of procedural delay at various steps.. LPA group (371 patients): Sputum smear to LPA deposition mean duration was 8.02 days, LPA deposition to LPA result upload mean duration was 3.78 days, LPA deposition to patients received LPA reports mean duration was 21.73 days and reports received to PMDT site admission (if drug resistant) mean duration was 3.61 days. Total time duration in category IV initiation was 32.63 days. CBNAAT group (50 patients): Sputum smear to CBNAAT deposition mean duration was 6.70 days, CBNAAT deposition to CBNAAT result upload mean duration was 1.13 days, CBNAAT deposition to patients received CBNAAT reports mean duration was 6.53 days and reports received to PMDT site admission (if R-resistant) mean duration was 3.8 days. Total time duration in category IV initiation was 12.4 days.. Major delay seen on part of receiving sensitivity reports indicates the need to stress upon field staff motivation, appropriate training, sensitisation and expert counselling.

Topics: Antitubercular Agents; Benchmarking; Delayed Diagnosis; Drug Administration Schedule; Humans; India; Mycobacterium tuberculosis; National Health Programs; Rifampin; Sputum; Tertiary Care Centers; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

To evaluate a multiplex PCR for rapid diagnosis of drug resistant mycobacterium tuberculosis (MTB) strain.. Cross-sectional observational study.. Department of Microbiology, Armed Forces Institute of Pathology (AFIP), Rawalpindi, from January to September 2018.. Over a period of 8 months, a total of 84 cultured positive samples were included in the study using nonprobability sampling techniques. MTB isolates were phenotypically characterised using MGIT 960 system for antituberculosis agents including rifampicin (RIF), isoniazid (INH), ethambutol (EMB) and Streptomycin. The DNA was extracted using Gentra system DNA extraction kit. The multiplex PCR was optimised for genetic characterisation of MTB samples for rpo B (rifampicin), kat G (isoniazid) and emb B (ethambutol) gene. The gel electrophoresis was performed to observe comparative banding pattern of amplified gene products.. For detecting drug resistance, the specificity and sensitivity of multiplex PCR in isolates was 100% and 100% for rifampicin, 100% and 71% for isoniazid, and 100% and 60% for ethambutol, respectively. When compared to phenotypically resistance results, the positive predictive value (PPV) was 100% each and the negative predictive value (NPV) was calculated to be 100%, 74% and 71% for RIF, INH and EMB, respectively.. Multiplex PCR is a useful gadget for quick determination of drug-resistant TB in specimens, hence permitting an initial therapeutic approach. However, for accurate management of patients, phenotypic method should be used to confirm results.

Topics: Antitubercular Agents; Cross-Sectional Studies; Drug Resistance, Bacterial; Ethambutol; Humans; Isoniazid; Multiplex Polymerase Chain Reaction; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

High mortality among individuals receiving retreatment for tuberculosis (RT-TB) persists, although reasons for these poor outcomes remain unclear.. We retrospectively reviewed 394 RT-TB patients diagnosed between January 2010 and June 2016 in Accra, Ghana.. Of RT-TB patients, 161 (40.9%) were treated empirically (negative/absent smear, culture or Xpert), of whom 30.4% (49/161) had only extrapulmonary TB signs or symptoms. Mortality during treatment was 19.4%; 15-day mortality was 10.8%. In multivariable proportional hazards regression, living with HIV (aHR=2.69 [95 CI: 1.51, 4.80], p<0.01) and previous loss-to-follow up (aHR=8.27 (95 CI: 1.10, 62.25), p=0.04) were associated with mortality, while drug susceptibility testing (DST, aHR=0.36 (95 CI: 0.13, 1.01), p=0.052) was protective. Isoniazid resistance was observed in 40% (23/58 tested) and rifampin resistance in 19.1% (12/63 tested).. High rates of extrapulmonary TB and smear/culture negative disease highlight the barriers to achieving DST-driven RT-TB regimens and the need for improved diagnostics. Our finding of poly-drug resistance in rifampin-susceptible cases supports access to comprehensive first line DST. Additionally, interventions to reduce mortality, especially in HIV co-infected RT-TB patients, are urgently needed.

Topics: Adult; Antitubercular Agents; Cohort Studies; Drug Resistance, Multiple, Bacterial; Female; Ghana; HIV Infections; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Multivariate Analysis; Mycobacterium tuberculosis; Proportional Hazards Models; Retreatment; Retrospective Studies; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

To investigate the prevalence and factors associated with the prevalence of multidrug/rifampicin-resistant tuberculosis among suspected drug resistant tuberculosis patients in Botswana.. A retrospective review of medical records of suspected drug resistant tuberculosis patients receiving care at public health facilities in Botswana was conducted from January, 2013 and December, 2014. Patient characteristics and drug susceptibility data were abstracted from 2568 medical records on to a pre-tested checklist form. The prevalence of multidrug/rifampicin resistance was computed. Bivariate and multivariate logistic regression was carried out to determine the factors associated with the prevalence of multidrug/rifampicin in the study population.. Overall, multidrug/ rifampicin - resistance among suspected drug resistant tuberculosis patients in Botswana were found in 139 (5.4%) cases with 1.3% among new cases and 7.7% among previously treated tuberculosis patients. Being a previously treated tuberculosis patient and having a positive smear were found to be factors associated with the prevalence of multidrug/rifampicin-resistant tuberculosis (p < 0.05). However, age, sex, living in urban area and HIV status were not associated with this disease (p > 0.05).. This study highlights a low burden of multidrug/rifampicin resistant tuberculosis among suspected drug resistant tuberculosis patients receiving care at public health facilities in Botswana. Strategies in controlling MDR/RR-TB should emphasize on effective implementation of Directly Observation Treatment - short course strategy, continuous surveillance of drug resistance cases, prevention of the development of new cases of MDR/RR-TB and to treat existing patients. Further interventions should focus on strengthening TB infection control activities.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antitubercular Agents; Botswana; Child; Child, Preschool; Drug Resistance, Multiple, Bacterial; Female; Humans; Infant; Male; Middle Aged; Mycobacterium tuberculosis; Prevalence; Retrospective Studies; Rifampin; Risk Factors; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

Regimens that could treat both rifampin-resistant (RR) and rifampin-susceptible tuberculosis (TB) while shortening the treatment duration have reached late-stage clinical trials. Decisions about whether and how to implement such regimens will require an understanding of their likely clinical impact and how this impact depends on local epidemiology and implementation strategy.. A Markov state-transition model of 100,000 representative South African adults with TB was used to simulate implementation of the regimen BPaMZ (bedaquiline, pretomanid, moxifloxacin, and pyrazinamide), either for RR-TB only or universally for all patients. Patient outcomes, including cure rates, time with active TB, and time on treatment, were compared to outcomes under current care. Sensitivity analyses varied the drug-resistance epidemiology, rifampin susceptibility testing practices, and regimen efficacy.. Using BPaMZ exclusively for RR-TB increased the proportion of all RR-TB that was cured by initial treatment from 60 ± 1% to 67 ± 1%. Expanding use of BPaMZ to all patients increased cure of RR-TB to 89 ± 1% and cure of all TB from 87.3 ± 0.1% to 89.5 ± 0.1%, while shortening treatment by 1.9 months/person. In sensitivity analyses, reducing the coverage of rifampin susceptibility testing resulted in lower projected proportions of patients cured under all regimen scenarios (current care, RR-only BPaMZ, and universal BPaMZ), compared to the proportions projected using South Africa's high coverage; however, this reduced coverage resulted in greater expected incremental benefits of universal BPaMZ implementation, both when compared to RR-only BPaMZ implementation and when compared to to current care under the same low rifampin susceptibility testing coverage. In settings with higher RR-TB prevalence, the benefits of BPaMZ were magnified both for RR-specific and universal BPaMZ implementation.. Novel regimens such as BPaMZ could improve RR-TB outcomes and shorten treatment for all patients, particularly with universal use. Decision-makers weighing early options for implementing such regimens at scale will want to consider the expected impact on patient outcomes and on the burden of treatment in their local context.

Topics: Adult; Antitubercular Agents; Diarylquinolines; Humans; Markov Chains; Nitroimidazoles; Prevalence; Pyrazinamide; Rifampin; South Africa; Treatment Outcome; Tuberculosis; Tuberculosis, Multidrug-Resistant

To evaluate the sensitivity, specificity, positive predictive and negative predictive values of Xpert mycobacterium tuberculosis and resistance to rifampicin by comparing it with acid-fast bacilli smear and culture in suspected tuberculosis patients.. The retrospective study was conducted at the Aga Khan University Hospital, Karachi, and comprised patient data from January 2013 to December 2016. Data related to children with clinical suspicion of pulmonary and extra-pulmonary tuberculosis based on Modified Kenneth Jones criteria, aged 1 month to 18 years whose samples (respiratory or non-respiratory) were sent for Xpert mycobacterium tuberculosis and resistance to rifampicin and acid-fast bacilli smear and culture con currently. Analysis was carried out by STATA 12 and Med Calc softwares .. Of the 91 cases, 50(54.9%) related to females. The overall median age of the patients was 12.5 years (interquartile range: 8 years). Overall, 42(46.2%) cases had extra-pulmonary tuberculosis. The Xpert test had 66.7% sensitivity compared to smear microscopy 47.6%. Overall sensitivity, specificity, positive predictive value and negative predictive value were 95.7%, 72%, 51.2% and 98.3% respectively when the two tests were compared.. Xpert mycobacterium tuberculosis was found to be more sensitive than acid-fast bacilli smear and culture in both pulmonary and extra-pulmonar y tuberculosis in children.

Topics: Adolescent; Antibiotics, Antitubercular; Child; Child, Preschool; Culture Techniques; Drug Resistance, Bacterial; Female; Humans; Infant; Male; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Pakistan; Retrospective Studies; Rifampin; Sensitivity and Specificity; Tertiary Care Centers; Tuberculosis; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Rapid detection of drug resistance in Mycobacterium tuberculosis (MTB) is essential for the efficient control of tuberculosis. Hence, in this study a nested-allele-specific (NAS) PCR, nested multiple allele-specific PCR (NMAS-PCR) and multiple allele-specific (MAS) PCR assays were evaluated that enabled detection of the most common mutations responsible for isoniazid (INH) and rifampicin (RIF) resistance in MTB isolates directly from clinical specimens.. Six pairs of primers, mutated and wild type, were used for the six targets such as codon 516, 526 and 531 of rpoB, codon 315 of katG and C15-T substitution in the promoter region of mabA-inhA using allele-specific (AS) PCR assays (NAS-PCR, NMAS-PCR and MAS-PCR). The performance of AS PCR method was compared with phenotypic drug susceptibility testing (DST).. The usefulness of AS PCR assays was evaluated with 391 clinical specimens (251 Acid fast bacilli smear positive and MTB culture positive; 93 smear negative and MTB culture positive; 47 smear positive and MTB culture negative) and 344 MTB culture positive isolates. With culture-based phenotypic DST as a reference standard, the sensitivity and specificity of the NAS-PCR, NMAS-PCR and MAS-PCR assay for drug resistance-related genetic mutation detection were 98.6 and 97.8 per cent for INH, 97.5 and 97.9 per cent for RIF and 98.9 and 100 per cent for multidrug resistance (MDR).. The performance of AS PCR assays showed that those could be less expensive and technically executable methods for rapid detection of MDR-TB directly from clinical specimens.

Topics: Alleles; Antitubercular Agents; Bacterial Proteins; Catalase; DNA-Directed RNA Polymerases; Drug Resistance, Multiple, Bacterial; Female; Humans; Isoniazid; Male; Multiplex Polymerase Chain Reaction; Mutation; Mycobacterium tuberculosis; Oxidoreductases; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant

为更好地推广和实践世界卫生组织"耐多药结核病（MDR-TB）和利福平耐药结核病（RR-TB）治疗指南（2018更新版）"和"耐药结核病治疗指南（2019整合版）"，提高我国广大结核病防治工作者对MDR-TB或RR-TB的诊治水平，中华医学会结核病学分会组织结核病领域的相关专家，结合我国的实际情况，制定了"中国耐多药和利福平耐药结核病治疗专家共识（2019年版）"。该共识介绍了MDR-TB或RR-TB化疗的基本原则和化疗药物，推荐了2套长程治疗方案和2套短程治疗方案，同时对化疗方案如何进行调整、抗结核药物不良反应的处理及化疗的注意事项等进行了阐述。共识还介绍了MDR-TB或RR-TB的其他治疗方法，如外科治疗、营养支持治疗、免疫治疗、介入治疗和中医药治疗。共识也强调了MDR-TB或RR-TB的治疗管理与监测；提出了MDR-TB或RR-TB治疗失败的处理措施。.

Topics: Antitubercular Agents; Consensus; Humans; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Tuberculosis (TB) is among the 10 most common worldwide causes of mortality. In Pakistan, estimated 510,000 tuberculosis patients had been diagnosed with an occurrence of 276/100,000. As per most recent global TB report 2018, Pakistan is amongst the 30 countries high TB with drug-resistant Mycobacterium tuberculosis particularly MDR (multi-drug resistant strains). A retrospective study had been designed using DR-TB patients' records from January 2013 to the December 2017 year from a public sector hospital in Karachi. Overall 315 drug-resistant tuberculosis patient's data had been incorporated in the study. All data had been analyzed using SPSS version 16 software. Chi-square test had been used to analyze the data with CI (confidence interval) 95% and level of significance 5%. The study result showed that 64.1% MDR patients, 27.9% MTB rifampicin resistance, 4.8% mono-drug resistant , XDR(1.6%), 1% poly-drug resistant and only 0.6% are MDR suspects showing no association of DR-TB with gender (p-value 0.787), age group (p-value 0.757), treatment outcomes (p-value 0.549), year of registration( p-value 0.206), first line treatment history(p-value 0.643) with a 95% confidence interval. The drug resistance TB cases have been periodically rising every year. Early identification is required to reduce the percent mortality and inhibit the disease transmission.

Topics: Adolescent; Adult; Aged; Antitubercular Agents; Child; Child, Preschool; Female; Humans; Male; Middle Aged; Mycobacterium tuberculosis; Pakistan; Prevalence; Public Health; Retrospective Studies; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant; Young Adult

Resistance pattern both in newly and previously treated-TB patients and risk factors associated in spread of tuberculosis are investigated in the current study. A total 244 Mycobacterium tuberculosis isolates were used for drug-susceptibility test against four drugs. Environmental risk factors were assessed by using self-designed history proforma. Among 244 TB-isolates, 64% were categorized as MDR-TB in drug-susceptibility test. Male proportion was 51% while 32% belonged to 15-34 years age group and 49% were from city Lahore whereas majority of people (31%) was working on daily wages. Divergent drug-resistance pattern was obtained; RIF (68%), SM (52%), EMB (51%). INH showed only (27%) resistance against first-line anti-TB drug. Drug-resistance prevalence for two drug combination was highest (50%) for (INH+SM) and (INH+EMB) followed by (RIF+SM) (49%) whereas for three drugs combination (INH+RIF+EMB) and (INH+RIF+SM) the prevalence was almost same 50% and 49% respectively while 66% patients were categorized as previously treated and 34% as new TB cases. In drug susceptibility test, 71% were identified as MDR-TB among New TB cases, while 63% were identified as MDR-TB from previously treated cases. Surprisingly DST results displayed that percentage prevalence of MDR-TB both in newly and previously treated cases was almost same.

Topics: Adolescent; Adult; Aged; Antitubercular Agents; Environment; Female; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Pakistan; Prevalence; Rifampin; Risk Factors; Tuberculosis; Tuberculosis, Multidrug-Resistant; Young Adult

In Lao People's Democratic Republic (PDR), tuberculosis (TB) prevalence was estimated at 540/100,000 in 2011. Nevertheless, little is known about the genetic characteristics and anti-TB drug resistance of the Mycobacterium tuberculosis population. The main objective of this work was to study the genetic characteristics and drug resistance of M. tuberculosis population collected during the first National TB Prevalence Survey (TBPS) of Lao PDR (2010-2011).. Two hundred and twenty two isolates collected during TBPS (2010-2011) were analyzed with the GenoType MTBDRplus test for M. tuberculosis identification and drug resistance detection. Then, 206 of the 222 isolates were characterized by spoligotyping and MIRU-VNTR typing.. Among the 222 M. tuberculosis isolates, 11 were mono-resistant to isoniazid and 2 were resistant to isoniazid and rifampicin (MDR-TB), using the GenoType MTBDRplus test. Among the 202 genetically characterized isolates, the East African-Indian (EAI) family was predominant (76.7%) followed by the Beijing (14.4%) and T (5.5%) families. EAI isolates came from all the country provinces, whereas Beijing isolates were found mainly in the northern and central provinces. A higher proportion of Beijing isolates was observed in people younger than 35 years compared to EAI. Moreover, the percentage of drug resistance was higher among Beijing (17.2%) than EAI (5.2%) isolates, and the two MDR-TB isolates belonged to the Beijing family. Combined analysis of the MIRU-VNTR and spoligotyping results (n = 202 isolates) revealed an estimated clustering rate of 11% and the occurrence of mini-outbreaks of drug-resistant TB caused by Beijing genotypes.. The EAI family, the ancient and endemic family in Asia, is predominant in Lao PDR whereas the prevalence of Beijing, the most harmful M. tuberculosis family for humans, is still low, differently from neighboring countries. However, its association with drug resistance, its presence in young patients and its potential association with recent transmission suggest that the Beijing family could change TB epidemiological pattern in Lao PDR. Therefore, efficient TB control and surveillance systems must be maintained and reinforced to prevent the emergence of highly transmissible and drug-resistant strains in Lao PDR, as observed in neighboring countries.

Topics: Adolescent; Adult; Antitubercular Agents; Cluster Analysis; Drug Resistance, Multiple, Bacterial; Female; Genotype; Humans; Isoniazid; Laos; Male; Middle Aged; Mycobacterium tuberculosis; Phylogeny; Prevalence; Rifampin; Tuberculosis, Multidrug-Resistant; Young Adult

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antitubercular Agents; Child; Child, Preschool; Female; Humans; Infant; Male; Middle Aged; Mobile Applications; Mycobacterium tuberculosis; Prospective Studies; Rifampin; Smartphone; South Africa; Time-to-Treatment; Tuberculosis, Multidrug-Resistant; Young Adult

South Africa led the world with guidelines on bedaquiline (BDQ) use as a single drug substitution to manage rifampin resistant tuberculosis regimen toxicity. We examined reasons for giving BDQ in a retrospective cohort: >75% of patients were switched to BDQ for toxicity (ototoxicity or renal dysfunction) rather than drug resistance.

Topics: Adult; Antitubercular Agents; Coinfection; Diarylquinolines; Drug Substitution; Drug Therapy, Combination; Female; HIV Infections; Humans; Male; Middle Aged; Mycobacterium tuberculosis; Retreatment; Retrospective Studies; Rifampin; South Africa; Treatment Outcome; Tuberculosis, Multidrug-Resistant

Tuberculosis is a bacterial infectious disease that is usually transmitted by inhalation of droplets containing the bacteria. The World Health Organization (WHO) estimates that approximately 10 million patients were newly diagnosed with tuberculosis in 2017. Rapid diagnosis relies on a combination of imaging and microbiological, molecular, and, rarely, immunological tests. Genotypic methods enable early diagnosis and allow highly accurate prediction of drug resistance. Phenotypic (culture-based) methods are the diagnostic gold standard. Standard management of patients with pan drug-susceptible pulmonary tuberculosis includes a combination of rifampicin, isoniazid, ethambutol and pyrazinamide for 2 months followed by rifampicin and isoniazid for additional 4 months, which leads to cure rates of >80%. With individualized treatment schemes, similar cure rates can be achieved for patients with multidrug-resistant tuberculosis.

Topics: Antitubercular Agents; Ethambutol; Humans; Isoniazid; Mycobacterium tuberculosis; Pyrazinamide; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Multidrug-resistant tuberculosis (MDR-TB) is a man-made problem when bacteria are resistant to at least two anti TB drugs (Rifampicin and Isoniazid). Currently from tuberculosis infected patients, two out of ten are developing MDR-TB and it is an emerging public health problem in Ethiopia. Despite high burden of MDR-TB in Ethiopia, the treatment outcomes and predictors related to incidence among MDR-TB patients is not studied in Oromia region, Ethiopia. Therefore, the present study assessed the predictors of time to unfavorable treatment outcomes among patients with multidrug resistant tuberculosis in Oromia region, Ethiopia.. Facility based retrospective cohort study was conducted at hospitals in Oromia Region. All registered MDR-TB patient charts from 2015 to 2017 were considered for the study. Data entry was done by using EPI data version 3.1 Statistical Software and data analysis was done by SPSS version 20. The descriptive statistics, frequency, median and range were employed. Bivariate and multivariate Cox proportional hazard regression analysis was used to identify predictors of time to unfavorable treatment outcomes of multidrug resistant tuberculosis. In multivariate Cox proportional hazard regression analysis, the variables with P- value less than and equal to 0.05 were considered as predictor variables for time to unfavorable treatment outcome of MDR-TB.. From the total of 415 (92.84%) complete MDR-TB charts, the overall cumulative probability of unfavorable treatment outcome at the end of the treatment (two years) was 21.21%. In multivariate Cox proportional hazard analysis initial culture result [AHR = 0.52; 95% CI: 0.29, 0.96], HIV test result [AHR = 3.76; 95% CI: 2.45, 5.78] and culture at the end of continuation phases [AHR = 0.12; 95% CI: 0.08, 0.20] were the predictors of unfavorable treatment outcome.. The magnitude of unfavorable treatment outcome at Oromia hospitals was lower than WHO regional report of 2018. This finding demonstrated that low unfavorable treatment outcomes for MDR-TB patients can be achieved in a resource-constrained and high TB-burden setting. Whereas, Initial culture result, HIV test result and culture at the end of continuation phases were determined as predictor factors with associated unfavorable treatment outcomes. Culture positive and HIV positive MDR-TB patients need special attention at the time of treatment.

Topics: Adolescent; Adult; Antitubercular Agents; Ethiopia; Female; Humans; Isoniazid; Male; Retrospective Studies; Rifampin; Survival Analysis; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Young Adult

South Africa ranks among the highest drug-resistant tuberculosis (DR-TB) burdened countries in the world. This study assessed the changes in resistance levels in culture confirmed. This study was conducted at the central academic laboratory of the KwaZulu-Natal province of South Africa.. We analysed data for all MTB cultures performed in the KwaZulu-Natal province between 2011 and 2014. The data were collected from the laboratory information system.. Out of 88 559 drug susceptibility results analysed, 18 352 (20.7%) were resistant to rifampicin (RIF) and 19 190 (21.7%) showed resistance to isoniazid (INH). The proportion of rifampicin resistant cases that were mono-resistant increased from 15.3% in 2011 to 21.4% in 2014 while INH mono-resistance (IMR) showed a range between 13.8% and 21.1%. The multidrug-resistant tuberculosis (MDR-TB) rates increased from 18.8% to 23.9% and the proportion of MDR-TB cases that had extensively drug-resistant tuberculosis remained between 10.2% and 11.1%. Most drug resistance was found in females between the ages of 15 and 44 years and the northern districts bordering high MDR-TB regions had the highest MDR-TB rates.. Our findings show increasing RIF mono-resistance (RMR) and a substantial amount of IMR. This highlights a need for an initial test that detects resistance to both these drugs so as to avoid using RIF monotherapy during continuous phase of treatment in patients with IMR. Furthermore, addition of INH will benefit patients with RMR. Although DR-TB is widespread, HIV and migration influence its distribution; therefore, TB control strategies should include interventions that target these aspects.

Topics: Adolescent; Adult; Antitubercular Agents; Extensively Drug-Resistant Tuberculosis; Female; Humans; Isoniazid; Male; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; South Africa; Tuberculosis, Multidrug-Resistant; Young Adult

To assess the quality and completeness of treatment and outcome data in the electronic tuberculosis (TB) and antiretroviral treatment (ART) registers in drug-resistant (DR-) TB patients at three treatment facilities in South Africa.. We did a retrospective cohort study using routinely-collected data from DR-TB registers of rifampicin resistant adults (≥18 years old), on ART, initiating DR-TB treatment between January 2012 and December 2013. We linked patient information from the DR-TB register to the ART register using patient identifiers and an algorithm based on string edit distance and date of birth. We describe data gaps and discrepancies found.. Overall, 2852 DR-TB patients met our inclusion criteria based on the DR-TB register data, and of these, 1685 (59%) could be matched to the ART registers. An additional 253 patients from the DR-TB registers were found in the ART registers, having initiated ART, despite the DR-TB register indicating that they were not on ART (or this data was missing). 11% of matched patients did not have TB treatment status recorded in the ART register despite being recorded as being on TB treatment in the DR-TB register, and 78% did not have an ART start date recorded in DR-TB register despite being on ART treatment as per the ART register. 11% of matched patients had a death recorded in one register but not the other, and of those with death recorded in both, 15% of dates differed by > 1 month.. The underreporting of death and the lack of ART or TB status in the electronic DR-TB and ART registers could negatively impact monitoring efforts by downplaying the state of the TB/HIV epidemic. Improved recording of these data sources, and data integration across systems, could improve the accuracy of reporting for the national HIV/ART and TB programs.

Topics: Adult; Anti-Retroviral Agents; Data Accuracy; Female; HIV Infections; Humans; Male; Registries; Retrospective Studies; Rifampin; South Africa; Tuberculosis; Tuberculosis, Multidrug-Resistant

Ethiopia stood third in drug-resistant tuberculosis (TB) in Africa, and more than 5,000 MDR-TB patients are reported each year. Greater than 90% of rifampicin (RIF) resistant strains are resistant to isoniazid (INH) and hence the objective of this study was to determine the prevalence and risk factors of RIF resistant MTB among presumptive TB cases at Dubti General Hospital, Afar, Ethiopia.. In this cross-sectional study, 384 presumptive TB cases were recruited and a structured questionnaire was used to collect socio-demographic and clinical data. Sputum samples were collected and examined using X-pertMTB/RIF assay. Bivariate, multivariate logistic regressions, and fishers' exact analysis were done to assess the associations between the prevalence of TB and MDR-TB with different socio-demographic and clinical variables.. In the present study, the overall prevalence of pulmonary TB was 24.5% (94/384), of this 4 (4.3%) isolates were resistant to RIF. History of anti-TB treatment (AOR = 2.4, 95% CI: 1.3-4.4 and TB contact (AOR = 3.6, 95% CI: 2.1-6.2 were significantly associated with gene X-pert MTB/RIF positive TB. Moreover, resistance to rifampicin was statistically associated with the history of TB contact with multi-drug resistant TB (P = 0.027) and khat chewer cases (P = 0.04).. The overall prevalence of TB and its drug-resistant were relatively higher than that of in the general population in Ethiopia. History of anti-TB treatment and TB contact were significantly associated with X-pert MTB/RIF positive MDR-TB.

Topics: Adolescent; Adult; Aged; Antibiotics, Antitubercular; Bacteriological Techniques; Child; Cross-Sectional Studies; Drug Resistance, Bacterial; Ethiopia; Female; Genotyping Techniques; Hospitals; Humans; Male; Middle Aged; Prevalence; Rifampin; Risk Factors; Sputum; Surveys and Questionnaires; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

Paradoxical reactions (PRs) are exaggerated inflammatory responses owing to recovery of cellular immunity following initiation of anti-tuberculous therapy (ATT). The presentation is worsening of pre-existing symptoms or development of new lesions. A 14-year-old girl with multi-drug-resistant tuberculosis developed a recurrent asymptomatic retropharyngeal abscess while on ATT. She required multiple aspirations of the abscess. Xpert MTB/RIF detected

Topics: Adolescent; Adrenal Cortex Hormones; Anti-Inflammatory Agents; Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Exudates and Transudates; Female; Humans; Mycobacterium tuberculosis; Paracentesis; Retropharyngeal Abscess; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant

To compare the incidence of anti tuberculosis drug-induced hepatotoxicity (ATDH) with those on old vs. revised WHO doses in human immunodeficiency virus (HIV) negative children. The secondary objective was to determine the overall incidence of hepatitis in children on Anti tubercular treatment (ATT) and isoniazid prophylactic therapy (IPT).. Children attending pediatric outpatient / admitted in wards, on ATT/ IPT between January 2007 and December 2017 (11 y) were included. Children were divided into Group 1 (treated based on old doses, from January 2007 to December 2011) and Group 2 (treated based on revised doses from January 2012 to December 2017). Children with multi drug resistant tuberculosis (MDRTB) and pre-existing liver disease were excluded.. A total of 515 children were enrolled. Twelve children developed ATDH with an overall incidence of 2.3%. Five out of 260 (1.9%) developed hepatitis with old doses vs. 7 of the 255 (2.7%) with revised doses; this difference was not statistically significant. When calculated only for active TB (excluding children on IPT), overall incidence of hepatitis was 2.7%. Comparison between group 1 (2.04%) and group 2 (3.5%) was again not statistically significant. Ten out of 12 children who developed hepatitis were restarted on ATT without recurrence. No child on IPT developed hepatitis. There was no mortality.. Revised WHO dosing does not increase incidence of hepatitis compared to old dosing in HIV negative children. Overall incidence was 2.3%. Hepatitis did not occur with IPT.

Topics: Adolescent; Antitubercular Agents; Chemical and Drug Induced Liver Injury; Child; Child, Preschool; Coinfection; Drug-Related Side Effects and Adverse Reactions; Female; Hepatitis; HIV; HIV Infections; Humans; Incidence; India; Infant; Isoniazid; Liver; Liver Function Tests; Male; Prospective Studies; Retrospective Studies; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Topics: Bacteriological Techniques; Humans; Microbial Sensitivity Tests; Microscopy; Molecular Diagnostic Techniques; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Accurate drug susceptibility testing (DST) of Mycobacterium tuberculosis in clinical specimens and culture isolates to first-line drugs is crucial for diagnosis and management of multidrug-resistant tuberculosis (MDR-TB). Resistance of M. tuberculosis to rifampicin is mainly due to mutations in hot-spot region of rpoB gene (HSR-rpoB). The prevalence of disputed (generally missed by rapid phenotypic DST methods) rpoB mutations, which mainly include L511P, D516Y, H526N, H526L, H526S, and L533P in HSR-rpoB and I572F in cluster II region of rpoB gene, is largely unknown. This study determined the occurrence of all disputed mutations in HSR-rpoB and at rpoB codon 572 in M. tuberculosis strains phenotypically susceptible to rifampicin in Kuwait.. A total of 242 M. tuberculosis isolates phenotypically susceptible to rifampicin were used. The DST against first-line drugs was performed by Mycobacteria growth indicator tube (MGIT) 960 system. Mutations in HSR-rpoB (and katG codon 315 and inhA-regulatory region for isoniazid resistance) were detected by GenoType MDBDRplus assay. The I572F mutation in cluster II region of rpoB was detected by developing a multiplex allele-specific (MAS)-PCR assay. Results were confirmed by PCR-sequencing of respective loci. Molecular detection of resistance for ethambutol and pyrazinamide and fingerprinting by spoligotyping were also performed for isolates with an rpoB mutation.. Among 242 rifampicin-susceptible isolates, 0 of 130 pansusceptible/monodrug-resistant isolates but 4 of 112 polydrug-resistant isolates contained a disputed rpoB mutation. All 4 isolates were also resistant to isoniazid and molecular screening identified additional resistance to pyrazinamide and ethambutol in one isolate each. In final analysis, 2 of 4 isolates were resistant to all 4 first-line drugs. Spoligotyping showed that the isolates belonged to different M. tuberculosis lineages.. Four of 242 (1.7%) rifampicin-susceptible M. tuberculosis isolates contained a disputed rpoB mutation including 2 isolates resistant to all four first-line drugs. The occurrence of a disputed rpoB mutation in polydrug-resistant M. tuberculosis isolates resistant at least to isoniazid (MDR-TB) suggests that polydrug-resistant strains should be checked for genotypic rifampicin resistance for optimal patient management since the failure/relapse rates are nearly same in isolates with a canonical or disputed rpoB mutation.

Topics: Antitubercular Agents; Bacterial Proteins; DNA-Directed RNA Polymerases; Drug Resistance, Multiple, Bacterial; Ethambutol; Genotype; Humans; Incidence; Isoniazid; Kuwait; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Polymerase Chain Reaction; Pyrazinamide; Rifampin; Tuberculosis, Multidrug-Resistant

Conventional indirect drug susceptibility testing (DST) of Mycobacterium tuberculosis with solid media is inexpensive and reliable, but time-consuming. This study aimed to evaluate direct DST for testing sputum samples without culture to significantly reduce the time required to detect multidrug-resistant tuberculosis (MDR-TB).. Direct and indirect DST of isoniazid (INH), rifampicin (RIF) and ethambutol (EMB) were performed on 334 sputum smear-positive specimens.. There was full agreement between the results obtained from direct testing and after isolation of the bacteria by culture. Thus, the sensitivity and specificity were observed to be 100% for all three tested drugs when compared with indirect DST. In comparison with indirect DST, none of the samples with the direct method took >25days to report the DST (between 15-25days with a mean detection time of 20 days).. Direct DST on solid media was shown to give reliable results at a much earlier stage than conventional phenotypic DST. The direct method was found to be more rapid, more accurate and simpler. In addition, it reduced the handling of pathogenic bacteria and thus reduced the bio hazards related to conventional DST.

Topics: Antitubercular Agents; Bacteriological Techniques; Drug Resistance, Multiple, Bacterial; Ethambutol; Humans; Iran; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant

To analyse the diagnostic performance of MTB/RIF assay for the diagnosis of pulmonary tuberculosis and detection of rifampicin resistance using sputum samples.. Observational cross-sectional study.. Provincial TB Reference Laboratory (PTRL), Hayatabad Medical Complex, Peshawar, Pakistan, from January to October 2015.. A total of 268 participants were consecutively enrolled in the study after meeting the inclusion criteria. Their sputum samples were collected and processed by N-acetyl-L-cysteine-sodium hydroxide (NALC-NaOH) method and GeneXpert MTB/RIF assay.. This study determined the overall sensitivity and specificity of MTB/RIF assay, it was 92.4% (86/93) and 97.1% (138/142), respectively. The sensitivity was 98.4% (60/61) in culture proven smear positive samples, whilst sensitivity in culture proven smear negative samples was 93.7% (30/32), using culture as reference standard.. GeneXpert MTB/RIF assay could greatly improve early diagnosis of PTB in smear negative cases as well as multidrug resistant tuberculosis.

Topics: Antibiotics, Antitubercular; Bacteriological Techniques; Cross-Sectional Studies; Female; Humans; Male; Molecular Diagnostic Techniques; Mycobacterium tuberculosis; Polymerase Chain Reaction; Rifampin; Sensitivity and Specificity; Sequence Analysis, DNA; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Topics: Antitubercular Agents; Child; Child, Preschool; Contact Tracing; Drug Resistance, Multiple, Bacterial; Drug Therapy, Combination; Ethambutol; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Prospective Studies; Pyrazinamide; Rifampin; Spain; Tuberculosis, Multidrug-Resistant

To evaluate modulatory effect of verapamil (VP) in rifampicin (RIF) activity and its effect in efflux pumps (EPs) transcript levels in Mycobacterium tuberculosis.. RIF and VP minimal inhibitory concentration, combinatory effect and detection of mutations were determined in 16 isolates. EPs transcript levels were determined in four isolates by real-time PCR after exposure to drugs.. VP showed good combinatory effect among RIF-resistant isolates. This effect was also observed in the relative transcript levels of EPs, mainly after 72 h of exposure, depending on the EP gene, genotype and the resistance profile of the isolate.. Additional regulatory mechanisms in the EP activities, as well as, interactions with other drug-specific resistance mechanisms need further investigation in M. tuberculosis.

Topics: Antitubercular Agents; Bacterial Proteins; Brazil; Catalase; DNA-Directed RNA Polymerases; Drug Resistance, Multiple, Bacterial; Drug Synergism; Drug Therapy, Combination; Gene Expression Regulation, Bacterial; Genotype; Humans; Membrane Transport Proteins; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Oxidoreductases; Rifampin; Time Factors; Tuberculosis, Multidrug-Resistant; Verapamil

To present results of the first national anti-tuberculosis (TB) drug resistance survey conducted in Lao PDR between May 2016 and August 2017 to determine the prevalence of resistance to first-line anti-TB drugs among new and previously treated pulmonary TB cases in the country.. Patients with sputum smear-positive pulmonary TB were enrolled from 42 TB laboratories distributed in 40 clusters throughout the country. Survey sites were selected using probability-proportional-to-size sampling among all diagnostic centres in the country. In addition to smear microscopy, all patients underwent Xpert MTB/RIF testing and those found positive to Mycobacterium tuberculosis underwent sputum culture and drug susceptibility testing using the proportion method on solid Löwenstein-Jensen medium.. Among 1006 eligible patients, 946 sputum smear-positive and Xpert MTB/RIF positive (Mycobacterium tuberculosis detected) patients were included in the survey, comprising 897 new and 49 previously treated TB cases. The prevalence of rifampicin-resistant TB was 1.2% (95% CI: 0.5-2.0%, n = 11/897) among new cases and 4.1% (95% CI: 0-9.6%, n = 2/49) among previously treated cases. Among the 946 TB cases confirmed by Xpert MTB/RIF, phenotypic drug sensitivity testing was available for 820 (776 new and 44 previously treated). The prevalence of multidrug-resistant TB (MDR-TB) was 0.5% (95% CI: 0-1.0%, n = 4/776) among new cases and 2.3% (95% CI: 0-6.7%, n = 1/44) among previously treated cases. No resistance to second-line injectable agents nor to fluoroquinolones was detected among MDR-TB patients.. The first national anti-TB drug resistance survey in Lao PDR demonstrated an encouragingly low prevalence of MDR-TB. The results appear lower than previous WHO estimates, and in line with the routine surveillance based on Xpert MTB/RIF testing (conducted among 50% of presumptive TB patients in 2017). The country should continue to expand its Xpert MTB/RIF network and strive to achieve universal drug susceptibility testing.. Présenter les résultats de la première surveillance nationale de la résistance aux médicaments antituberculeux, menée en République Démocratique Populaire (RDP) Lao entre mai 2016 et août 2017 afin de déterminer la prévalence de la résistance aux médicaments antituberculeux de première intention chez les nouveaux cas et les cas déjà traités de tuberculose (TB) pulmonaire dans le pays. MÉTHODES: Les patients atteints de TB pulmonaire à frottis d'expectoration positif ont été recrutés dans 42 laboratoires TB répartis dans 40 groupes à travers tout le pays. Les sites de surveillance ont été sélectionnés sur la base d'un échantillon probabiliste proportionnel à la taille parmi tous les centres de diagnostic du pays. Outre l'examen microscopique des frottis, tous les patients ont subi un test Xpert MTB/RIF et ceux trouvés positifs pour Mycobacterium tuberculosis ont subi une culture d'expectorations et un test de sensibilité aux médicaments en utilisant la méthode des proportions sur un milieu solide de Löwenstein-Jensen. RÉSULTATS: Parmi les 1.006 patients éligibles, 946 patients à frottis positif et Xpert MTB/RIF positif (Mycobacterium tuberculosis détecté) ont été inclus dans la surveillance, comprenant 897 nouveaux cas et 49 cas de TB déjà traités. La prévalence de la TB résistante à la rifampicine était de 1,2% (IC95%: 0,5-2,0%, n = 11/897) chez les nouveaux cas et de 4,1% (IC95%: 0-9,6%, n = 2/49) chez les cas traités. Parmi les 946 cas de TB confirmés par Xpert MTB/RIF, des tests de sensibilité phénotypique aux médicaments étaient disponibles pour 820 (776 nouveaux cas et 44 cas traités antérieurement). La prévalence de la TB multirésistante (TB-MDR) était de 0,5% (IC95%: 0-1,0%, n = 4/776) chez les nouveaux cas et de 2,3% (IC95%: 0 à 6,7%, n = 1/44) parmi les cas précédemment traités. Aucune résistance aux agents injectables de deuxième intention ni aux fluoroquinolones n'a été détectée chez les patients atteints de TB-MDR.. La première surveillance nationale de la résistance aux médicaments antituberculeux menée en RDP Lao a révélé une prévalence rassurante de la TB-MDR. Les résultats apparaissent inférieurs aux estimations précédentes de l’OMS et conformes à la surveillance de routine basée sur le test Xpert MTB/RIF (menée auprès de 50% des patients atteints de TB présumée en 2017). Le pays devrait continuer à élargir son réseau Xpert MTB/RIF et s'efforcer d'atteindre des tests universels de sensibilité aux médicaments.

Topics: Adolescent; Adult; Aged; Antibiotics, Antitubercular; Child; Child, Preschool; Drug Resistance, Bacterial; Female; Humans; Infant; Infant, Newborn; Laos; Male; Mass Screening; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Prevalence; Rifampin; Sputum; Surveys and Questionnaires; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

Isoniazid-resistant, rifampin susceptible tuberculosis (INHR-TB) is the most common form of drug resistant TB globally. Treatment of INHR-TB with standard first-line therapy is associated with high rates of multidrug resistant TB (MDR-TB). We modelled the potential impact of INHR-TB detection and appropriate treatment on MDR-TB prevalence.. A decision analysis model was developed to compare three different strategies for the detection of TB (AFB smear, Xpert MTB/RIF, and Line-Probe Assays (LPA)), combined with appropriate treatment. The population evaluated were patients with a globally representative prevalence of newly diagnosed, drug-susceptible (88.6%), isoniazid-resistant (7.3%), and multidrug resistant (4.1%) pulmonary TB. Our primary outcome was the proportion of patients with MDR-TB after initial attempt at diagnosis and treatment within a 2-year period. Secondary outcomes were the proportion of i) individuals with detected TB who acquired MDR-TB ii) individuals who died after initial attempt at diagnosis and treatment.. After initial attempt at diagnosis and treatment, LPA combined with appropriate INHR-TB therapy resulted in a lower proportion of prevalent MDR-TB (1.61%; 95% Uncertainty Range (UR: 2.5th and 97.5th percentiles generated from 10 000 Monte Carlo simulation trials) 1.61-1.65), when compared to Xpert (1.84%; 95% UR 1.82-1.85) and AFB smear (3.21%; 95% UR 3.19-3.26). LPA also resulted in fewer cases of acquired MDR-TB in those with detected TB (0.35%; 95% UR 0.34-0.35), when compared to Xpert (0.67%; 95% UR 0.65-0.67) and AFB smear (0.68%; 95% UR 0.67-0.69). The majority of acquired MDR-TB arose from the treatment of INHR-TB in all strategies. Xpert-based strategies resulted in a lower proportion of death (2.89%; 95% UR 2.87-2.90) compared to LPA (2.93%; 95% UR 2.91-2.94) and AFB smear (3.21%; 95% UR 3.19-3.23).. Accurate diagnosis and tailored treatment of INHR-TB with LPA led to an almost 50% relative decrease in acquired MDR-TB when compared with an Xpert MTB/RIF strategy. Continued reliance on diagnostic and treatment protocols that ignore INHR-TB will likely result in further generation of MDR-TB.

Topics: Antitubercular Agents; Decision Support Techniques; Drug Resistance, Bacterial; Humans; Isoniazid; Models, Theoretical; Prevalence; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant; Uncertainty

Tuberculosis (TB) is a worldwide public health concern, including in high-resource countries with a low prevalence of TB. Xpert MTB/RIF assay was developed to improve TB and rifampicin (RIF) resistance detection, but sensitivity remains poor on smear-negative sputum. Xpert MTB/RIF Ultra assay was designed to enhance the sensitivity of TB detection in clinical samples. Herein, we evaluated retrospectively the performance of this test on smear-negative respiratory samples. Respiratory specimens with smear-negative and a Mycobacterium tuberculosis (MTB) complex-positive culture were retrospectively selected from those taken from patients during routine care, and analysed in the Mycobacteria Laboratory of the Lyon University hospital, France. Specimens were stored at - 20 °C before testing by Xpert MTB/RIF Ultra. For each sample, growth delay and date of anti-TB treatment initiation were recorded. Forty-six samples-29 sputum, 8 bronchial aspirates, 6 broncho-alveolar lavages, and 3 gastric aspirates-were selected. Among samples collected before treatment initiation (n = 33), sensitivity was 81.8% (95% CI [64.5; 93.0]) and there was a significant correlation between the quantitative measurements (Ct) of Xpert MTB/RIF Ultra assay and the time to growth detection in culture. Among samples collected after treatment initiation (n = 12), sensitivity was 100%, without correlation with time to growth detection due to presence of afterglow DNA in samples. In high-resource settings, the Xpert MTB/RIF Ultra test represents a useful tool for pulmonary TB diagnosis, notably for the paucibacillary forms. Moreover, quantitative measurement of Xpert MTB/RIF Ultra could help to predict time to MTB culture positivity and be used as a quality indicator of MTB culture process.

Topics: Antibiotics, Antitubercular; Diagnostic Tests, Routine; Drug Resistance, Bacterial; Humans; Molecular Diagnostic Techniques; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

India has the world's highest tuberculosis burden, and Mumbai is particularly affected by multidrug resistant tuberculosis (MDR-TB). WHO recommends short, intensive treatment ("Short Course") for previously untreated pulmonary MDR-TB patients but does not require universal drug susceptibility testing (DST) before Short Course. DST would likely screen out many MDR-TB patients in places like Mumbai with significant drug resistance.. MDR-TB patients at a private clinic were recruited for a prospective observational cohort. Short Course eligibility was evaluated by clinical criteria and DST results. Eligibility by DST was classified as rifampin monoresistance (as tested by Xpert MTB/RIF), rifampin, fluoroquinolones, and 2nd-line injectable drugs resistance (as tested by line probe assays) and resistance to other drugs.. Of 559 participants with MDR-TB, 33% met clinical eligibility for Short Course. DST for rifampin, fluoroquinolones, and 2nd-line injectable drugs excluded 74.7% of participants. Complete phenotypic DST excluded 96.6% of participants. Prior treatment with either 1st or 2nd-line drugs did not significantly affect eligibility.. In a global MDR-TB hotspot, < 5% of participants with MDR-TB were appropriate for Short Course by clinical characteristics and DST results. Rapid molecular testing would not sufficiently identify drug resistance in this population. Eligibility rates were not significantly reduced by prior TB treatment.

Topics: Adult; Ambulatory Care Facilities; Antitubercular Agents; Cohort Studies; Drug Administration Schedule; Eligibility Determination; Female; Fluoroquinolones; Guideline Adherence; Hospitals, Private; Humans; India; Male; Middle Aged; Patient Selection; Rifampin; Tuberculosis, Multidrug-Resistant; Young Adult

The Mycobacterium tuberculosis lineage 4 strains CDC1551 and H37Rv develop tolerance to multiple antibiotics upon macrophage residence. To determine whether macrophage-induced tolerance is a general feature of clinical M. tuberculosis isolates, we assessed macrophage-induced drug tolerance in strains from lineages 1-3, representing the other predominant M. tuberculosis strains responsible for tuberculosis globally. All 3 lineages developed isoniazid tolerance. While lineage 1, 3, and 4 strains developed rifampin tolerance, lineage 2 Beijing strains did not. Their failure to develop tolerance may be explained by their harboring of a loss-of-function mutation in the Rv1258c efflux pump that is linked to macrophage-induced rifampicin tolerance.

Topics: Antitubercular Agents; ATP-Binding Cassette Transporters; Bacterial Proteins; Drug Resistance, Multiple, Bacterial; Humans; Isoniazid; Loss of Function Mutation; Macrophages; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; THP-1 Cells; Tuberculosis, Multidrug-Resistant

Multidrug-resistant tuberculosis (MDR-TB) jeopardizes global TB control. The prevalence and predictors of Rifampicin-resistant (RR) TB, a proxy for MDR-TB, and the treatment outcomes with standard and shortened regimens have not been assessed in post-conflict regions, such as the South Kivu province in the eastern Democratic Republic of the Congo (DRC). We aimed to fill this knowledge gap and to inform the DRC National TB Program.. of adults and children evaluated for pulmonary TB by sputum smear microscopy and Xpert MTB/RIF (Xpert) from February 2012 to June 2017. Multivariable logistic regression, Kaplan-Meier estimates, and multivariable Cox regression were used to assess independent predictors of RR-TB and treatment failure/death.. Of 1535 patients Xpert-positive for TB, 11% had RR-TB. Independent predictors of RR-TB were a positive sputum smear (adjusted odds ratio [aOR] 2.42, 95% confidence interval [CI] 1.63-3.59), retreatment of TB (aOR 4.92, 95% CI 2.31-10.45), and one or more prior TB episodes (aOR 1.77 per episode, 95% CI 1.01-3.10). Over 45% of RR-TB patients had no prior TB history or treatment. The median time from Xpert diagnosis to RR-TB treatment initiation was 12 days (interquartile range 3-60.2). Cures were achieved in 30/36 (83%) and 84/114 (74%) of patients on 9- vs 20/24-month MDR-TB regimens, respectively (P = .06). Predictors of treatment failure/death were the absence of directly observed therapy (DOT; adjusted hazard ratio [aHR] 2.77, 95% CI 1.2-6.66) and any serious adverse drug event (aHR 4.28, 95% CI 1.88-9.71).. Favorable RR-TB cure rates are achievable in this post-conflict setting with a high RR-TB prevalence. An expanded Xpert scale-up; the prompt initiation of shorter, safer, highly effective MDR-TB regimens; and treatment adherence support are critically needed to optimize outcomes.

Topics: Adult; Antibiotics, Antitubercular; Child; Cohort Studies; Democratic Republic of the Congo; Drug Resistance, Bacterial; Humans; Mycobacterium tuberculosis; Prevalence; Retrospective Studies; Rifampin; Sputum; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

To determine the proportion of rifampicin-resistant tuberculosis (RR-TB) patients who accessed second-line drug susceptibility testing (SL-DST) results following introduction of the Hain technology in southern provinces, Zimbabwe.. Cohort study using secondary data.. Xpert MTB/RIF results were used to identify 133 RR-TB patients for this study. Their mean age (SD) was 37.9 (11.1) years, 83 (62%) were males and 106 (80%) were HIV-infected. There were 6 (5%) participants who had pre-treatment attrition. Of the 133 pulmonary TB (PTB) patients, 117 (80%) had additional sputum specimens collected; 96 (72%) specimens reached the National TB Reference Laboratory (NTBRL); 95 (71%) were processed; 68 (51%) had SL-DST results. Only 53 (40%) SL-DST results reached the peripheral facilities. Median time from specimen reception at the NTBRL to SL-DSTs was 40 days, interquartile range (IQR: 28-67). Median time from presumptive diagnosis of RR-TB by health care worker to SL-DST results was 50days (IQR: 39-80), and increased to 79days (IQR: 39-101) in facilities >250km from the NTBRL. The proportion with any fluoroquinolone resistance was 9 (13.2%).. Although RR-TB patients with PTB were initiated timely on treatment, access to SL-DSTs by facilities needs improvement. Health inequities exist as remote areas are less likely to get SL-DST results in time.

Topics: Adolescent; Adult; Aged; Antitubercular Agents; Cohort Studies; Diagnostic Tests, Routine; Drug Resistance, Bacterial; Female; Fluoroquinolones; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant; Young Adult; Zimbabwe

Little is known about the treatment experiences of pregnant women with rifampin-resistant tuberculosis. We conducted qualitative interviews with 10 women who had this condition; 9 reported facing discrimination from healthcare providers. Our findings underscore an urgent need to ensure a human-rights-based, patient-centered approach for women with rifampin-resistant tuberculosis who are pregnant.

Topics: Antibiotics, Antitubercular; Drug Resistance, Bacterial; Female; Health Personnel; Humans; Pregnancy; Rifampin; Social Discrimination; Tuberculosis, Multidrug-Resistant

Department of Microbiology.. To determine the common mutations responsible for rifampicin resistance in TB cases detected by Xpert MTB/RIF assay.. Results of Xpert MTB/RIF assay performed from 2013 to 2017 were analysed for missing probes in different types of specimens containing rifampicin resistant MTB.. Successful results were obtained in14872 of the total 15129 specimens processed by Xpert MTB/RIF assay, of which 9458 (63.6%) were sputum and 5414 (36.4%) were extrapulmonary specimens. MTB was detected in 1624 (17.17%) sputum and 1121 (20.70%) extrapulmonary specimens of which 409 (25.18%) and 277 (24.71%) were rifampicin resistant respectively. Probe E (83.82%) was the commonest probe responsible for rifampicin resistance followed by D (3.93%) and B (3.79%). Mutation in probe C (0.29%) was very rare. Combination of missing probes like AB (0.73%), DE (1.16%) and ADE (0.14%) was observed. 22 (3.2%) specimens showed presence of all five probes.. Xpert MTB/RIF assay uses various combinations of probe to detect MTB along with rifampicin resistance and is a valuable diagnostic tool. It can become a useful epidemiological tool to identify dynamics of transmission of TB by addition of few more probes to identify mutations at specific codons.

Topics: Antibiotics, Antitubercular; Bacterial Proteins; DNA Probes; DNA-Directed RNA Polymerases; Drug Resistance, Bacterial; Female; Humans; India; Male; Molecular Epidemiology; Mutation; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Real-Time Polymerase Chain Reaction; Rifampin; Tertiary Care Centers; Tuberculosis, Multidrug-Resistant

During 2009-2013, Xpert MTB/RIF testing was decentralized in Tanzania. Standardized treatment of multidrug-resistant/rifampicin-resistant tuberculosis (MDR/RR-TB) was centralized at the Kibong'oto Infectious Diseases Hospital. Initially, Xpert MTB/RIF results were confirmed and complemented with phenotypic drug susceptibility testing before MDR-TB treatment was started. Since 2013, the decision to start MDR-TB treatment in patients with RR-TB relied on Xpert MTB/RIF results.. A retrospective cohort study of predictors of unsuccessful treatment outcomes (including death, lost to follow-up and treatment failure) was carried out.. During the study period, 201 patients started MDR-TB treatment. The number of patients starting MDR-TB treatment increased over time. Out of 201 patients, 48 (23.9%) had an unsuccessful treatment outcome. The median time between sample collection and MDR-TB treatment initiation was reduced from 155 d (IQR 40-228) in the 2009-2012 period to 26 d (IQR 13-64) in 2013. Patients who started MDR-TB treatment in 2013 were more likely (adjusted OR 2.3; 95% CI 1.1-4.7; p=0.02) to have an unsuccessful treatment outcome.. Xpert MTB/RIF testing increased enrolment on MDR-TB treatment. Reliance on Xpert MTB/RIF results to start MDR-TB treatment reduced time to treatment. However, treatment outcomes did not improve.

Topics: Adolescent; Adult; Female; Humans; Male; Middle Aged; Molecular Diagnostic Techniques; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Tanzania; Time-to-Treatment; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Young Adult

The genetic diversity of. To investigate mutations related to drug resistance and bacterial genotypes in. Isolates showed mutations in the. This is the first report from Ecuador; it describes five new mutations in

Topics: Antitubercular Agents; Drug Resistance, Bacterial; Ecuador; Genetic Variation; Genotype; Humans; Isoniazid; Minisatellite Repeats; Mutation; Mycobacterium tuberculosis; Phenotype; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant

Rifampicin-resistant tuberculosis (RR-TB) is largely underdetected in Indonesia. Xpert MTB/RIF (Xpert) has recently been introduced, prioritizing patients at risk of RR-TB, followed by phenotypic drug-susceptibility (DST) if rifampicin resistance is detected.. This study investigated Xpert-based management of presumptive RR-TB cases under routine practice in West Java, Indonesia.. We examined all records of patients tested with Xpert in the referral hospital for West Java in 2015-2016. We measured loss across a limited cascade of care, time to Xpert diagnosis and the commencement of initial second-line treatment, and identified factors associated with diagnostic and treatment delay. Additionally, we analyzed the appropriateness of treatment according to DST results.. Of 3415 patients with presumptive RR-TB, 3215 (94%) were tested by Xpert, of whom 339 (10.5%) were diagnosed as RR-TB. 288 (85%) of 339 RR-TB patients started initial second-line TB treatment, with 48 (14%) patients being lost between diagnosis and pre-treatment assessment. Second-line treatment was commenced at a median of 41 days (IQR 29-70) after RR-TB diagnosis. Delays in both diagnosis and treatment initiation were observed in 104 (52%) of 201 RR-TB patients with identifiable referral date. Rural residence was associated with delay to diagnosis (adjusted OR 2.7; 95%CI 1.5-5.2) and treatment initiation (adjusted OR 2.0; 1.2-3.4). Of 162 patients with available DST result, 107 (66%) had multidrug-resistant tuberculosis (MDR-TB) and 32 (20%) had either pre-extensively drug resistant (pre-XDR) or extensively drug resistant tuberculosis (XDR-TB). We estimated that with the current algorithm 41% of pre-XDR or XDR-TB patients are diagnosed, and 33% of them started on an appropriate treatment regimen.. Many patients with Xpert-diagnosed RR-TB either do not start MDR-TB treatment or encountered diagnostic and treatment delays under programmatic conditions in Indonesia, and most pre-XDR and XDR-TB cases remain undiagnosed. Further expansion and ongoing quality improvement of RR-TB services are urgently needed.

Topics: Adult; Antibiotics, Antitubercular; Cohort Studies; Drug Resistance, Bacterial; Expert Systems; Female; Humans; Indonesia; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Time-to-Treatment; Tuberculosis, Multidrug-Resistant

A major opportunistic infection among HIV-infected people is tuberculosis (TB). It accelerates the deadly progression of HIV which results in further decline in the patient's immune status and early death. More than 9 million people suffer from this debilitating coinfection worldwide. More worrisome is the fact that some patients now develop resistance to rifampicin, a first-line drug against TB. This study therefore aimed at determining the rifampicin-resistant TB prevalence rate among known HIV-positive patients in Oyo State. This cross-sectional study was performed by collecting suitable sputum samples from 397 known HIV patients who attended ART Clinic between January and December 2017. The samples were analyzed using the GeneXpert machine, a real-time polymerase chain reaction-based equipment. Of the total 397 tested, 172 (43.3%) were male while 225 (56.7%) were females. Fifty (12.6%) of the 397 known HIV patients tested positive to TB and 6 (12%) of the 50 were resistant to rifampicin. Four (2.3%) of the 172 males had rifampicin-resistant TB and 2 (0.9%) of the 225 females were resistant to rifampicin. Age group 31-40 years was the most affected with pulmonary TB while age group 10-20 years was the most affected with rifampicin-resistant TB. Six (1.5%) of the total 397 were rifampicin resistant. In conclusion, strict compliance with the infection control measures is strongly advocated for to prevent further transmission of Mycobacterium tuberculosis to people living with HIV most of whom have their immune system already weakened.

Topics: Adolescent; Adult; Aged, 80 and over; Antibiotics, Antitubercular; Child; Female; HIV Infections; Humans; Male; Mycobacterium tuberculosis; Nigeria; Rifampin; Tuberculosis, Multidrug-Resistant; Young Adult

The global rise of multi-drug resistant M. tuberculosis demands unconventional treatment to enhance the efficiency of current drugs. Punica granatum, which is known as pomegranate, is considered as a member of the Punicaceae family. Pomegranate, which is broadly documented for its activity against a wide spectrum of bacterial pathogens, deserves further scrutiny in this respect.. Within this scope, this study investigated the effect of fresh pomegranate juice (FPJ) on the antibacterial activity of anti-tuberculosis drugs (Rifampin (R) and Isoniazid (INH)) against MDR-TB clinical isolates. The drug resistance profiles in M. tuberculosis clinical isolates were determined by susceptibility test using BACTEC MGIT 960 system. Four concentrations of fresh pomegranate juice (FPJ) (5%, 10%, 15%, and 20%) were evaluated in combination with R and INH at a dose range of (1.0 µg/ml) and (0.1 µg/ml), respectively against the MDR-TB isolates by the BACTEC MGIT 960 system. Moreover, this study scrutinized individual phenolic compounds of FPJ by using highperformance liquid chromatography (HPLC). The total polyphenols (TP), total flavonoid (TF), total anthocyanins content (TAC), and the antioxidant capacity were also assessed in FPJ.. Synergistic effects were observed between R and INH with FPJ against all tested strains. However, combination therapy of rifampin was more effective than isoniazid one. Therefore, the combination of R and FPJ has been used against (27) MDR-TB clinical isolates. 5% of FPJ plus R (1.0 µg/ml) were found to suppress the growth of one isolates for first group (INH and R resistant). However, 5% of FPJ demonstrated no synergistic impact with R for second (SM, R and INH resistant) and third group (INH, EMB, R and SM resistant). Moreover, 10% of FPJ and R (1.0 μg/ml) inhibited the bacterial growth of three isolates of first group and two isolates and one isolate for second and third group, respectively. Remarkably, 15% of FPJ plus R (1.0 µg/ml) appeared to inhibit the growth of MDR-TB isolates for all tested groups indicating a strong synergistic effect. Regarding H37RV, the complete inhibition of the bacterial growth was found to occur at 15% and 20% concentrations of FPJ only. Minimum inhibitory concentration (MIC) of FPJ ranged from (4% to13%) for first group and from (10% to15%) for second and third group. Thus, FPJ at 15% inhibited 100% of bacteria for all tested isolates (MIC100% =15%). Phenolic compounds identified in FPJ were gallic acid, benzoic acid, syringic, folic acid, pelargonidin, naringin+ellagic acid, naringenin, chlorogenic acid, caffeic acid, catechin, myricetin, kaempferol, quercetin, cyanidin-3-glycoside, p-cummaric acid, ferulic acid, and rutin. Total phenolic (TP), total flavonoid (TF), and total anthocyanin (TA) content were 841.5 mg/L, 638.73 mg RE/L, and 47.43 mg/L, accordingly.. Overall, FPJ displayed synergistic effect with R against MDR-TB clinical isolates due to its high content of polyphenol and antioxidant capability.

Topics: Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Fruit and Vegetable Juices; Humans; Isoniazid; Lythraceae; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Polyphenols; Rifampin; Tuberculosis, Multidrug-Resistant

Tajikistan is among the 30 countries with the highest multidrug-resistant tuberculosis (MDR-TB) burden.. To investigate the risk factors for unfavourable treatment outcomes among rifampicin-resistant (RR)/MDR-TB patients.. Retrospective medical chart review of RR/MDR-TB patients enrolled for treatment in 2012-2013.. Of 601 RR/MDR-TB patients, 58 (9.7%) had pre-extensively drug-resistant TB (pre-XDR-TB; i.e., MDR-TB with additional resistance to a fluoroquinolone or second-line injectable agent) and 45 (8%) had XDR-TB (MDR-TB with additional resistance to both). Treatment failure and death were reported in respectively 40 (7%) and 89 (15%) cases; 60 (10%) patients were lost to follow-up (LTFU). In multivariable analysis, treatment failure was associated with pre-XDR-TB (adjusted odds ratio [aOR] 3.67, 95%CI 1.47-9.18) or XDR-TB (aOR 8.61, 95%CI 3.48-21.34). Death was associated with age >45 years vs. <25 years (aOR 3.47, 95%CI 1.68-7.19) and no record of any adverse event during treatment (aOR 2.55, 95%CI 1.48-4.39). Changing place of residence during treatment was an independent predictor of LTFU (aOR 4.61, 95%CI 2.41-8.8).. Our findings highlight the need for 1) the use of regimens with new anti-tuberculosis drugs; 2) good handover of TB patients and 3) effective tracing mechanisms if patients change a place of residence to prevent LTFU.

Topics: Adult; Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Extensively Drug-Resistant Tuberculosis; Female; Humans; Male; Middle Aged; Retrospective Studies; Rifampin; Risk Factors; Tajikistan; Treatment Failure; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Young Adult

Understanding why some multidrug-resistant tuberculosis cases are not detected by rapid phenotypic and genotypic routine clinical tests is essential to improve diagnostic assays and advance toward personalized tuberculosis treatment. Here, we combine whole-genome sequencing with single-colony phenotyping to identify a multidrug-resistant strain that had infected a patient for 9 years. Our investigation revealed the failure of rapid testing and genome-based prediction tools to identify the multidrug-resistant strain. The false-negative findings were caused by uncommon rifampicin and isoniazid resistance mutations. Although whole-genome sequencing data helped to personalize treatment, the patient developed extensively drug-resistant tuberculosis, highlighting the importance of coupling new diagnostic methods with appropriate treatment regimens.

Topics: Antitubercular Agents; Bacterial Proteins; Diagnostic Errors; Drug Resistance, Multiple, Bacterial; Extensively Drug-Resistant Tuberculosis; Genome, Bacterial; Genotype; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifampin; Sequence Analysis, DNA; Tuberculosis, Multidrug-Resistant; Whole Genome Sequencing

Drug resistance in tuberculosis (TB) is a major public health challenge in developing countries such as Pakistan. Multiplex allele specific polymerase chain reaction (MAS-PCR) is a DNA amplification method that could contribute to rapid detection and control of drug resistant tuberculosis (DR-TB) in Pakistan. The purpose of this study was to test the utility of MAS-PCR to detect resistance in Pakistan. Drug susceptibility testing (DST) was used to identify rifampicin resistant and susceptible clinical isolates from TB cases in Pakistan. MAS-PCR was used to detect the most frequent mutations in the gene rpoB among 213 resistant and 37 susceptible isolates. Among 213 clinical isolates, MAS-PCR identified mutation D435Y (Asp435Tyr) in 24 (11.3%) cases, H445Y (His445Tyr) in 14 (6.6%), S450L (Ser450Leu) in 124 (58.2%) and S450W (Ser450Trp) in 18 (8.4%) cases. MAS-PCR did not detect known mutations in 33 (15.5%) cases. Among 12 cases, a novel mutation at codon 434 (Met434Ile) and a common variant at codon 435 (Asp435Tyr) was detected in rpoB gene which is indicative of double mutation. In 4 isolates, a novel mutation at codon 432 (Gln432Pro) was identified. In an additional 4 isolates, mutations Met434Val and His445Asn were identified. Moreover, a mutation in rpoB (Leu452Pro) was found in 5 isolates. DNA sequencing confirmed the absence of mutations in rpoB in the 8 remaining isolates. MAS-PCR had 88.3% sensitivity and 100% specificity using DST as the reference, which suggested that this method could be implemented as an initial marker for screening of multi-drug resistant tuberculosis (MDR-TB) in Pakistan.

Topics: Bacterial Proteins; DNA-Directed RNA Polymerases; Drug Resistance, Multiple, Bacterial; Humans; Microbial Sensitivity Tests; Multiplex Polymerase Chain Reaction; Mycobacterium tuberculosis; Pakistan; Rifampin; Tuberculosis, Multidrug-Resistant

Tuberculosis (TB), an ancient scourge of humanity known for several thousands of years, is still a significant public health challenge in many countries today even though some progress has been made in recent years in controlling the disease. The study's aim was to determine the prevalence of mutations responsible for drug resistance in Mycobacterium tuberculosis among patients visiting selected health centers in Nairobi, Kenya.. The cross-sectional study involved 132 TB positive patients visiting Mbagathi and Chandaria hospitals between September 2015 and August 2016. Sputum samples were collected from the participants and handled in a biosafety level 3 laboratory at the Kenya Medical Research Institute (KEMRI). Samples were decontaminated using N-Acetyl-L-Cysteine (NALC) - Sodium Hydroxide (NALC-NaOH), stained using Zeihl-Neelsen (ZN), and cultured in Mycobacterium Growth Indicator Tube (MGIT). DNA extracted from cultured isolates using Genolyse™ technique was subjected to Multiplex PCR amplification and reverse hybridization for detection of drug resistance mutations on rpoB, katG, inhA, gyrA, gyrB, rrs and eis genes using Hain Genotype MTBDRplus and MTBDRsl.. All 132 (100%) patients included in the study were culture positive for M. tuberculosis. Among them, 72 (54%) were male while the remaining 60 (46%) were female. The mean age of the patients was 26.4 ± 19.4 (SD) with a range of 18 to 60 years. Overall, the prevalence of the resistance to first and second-line TB drugs was 1.5% (2/132). Resistance to isoniazid (INH) was observed in 1 of 132 patients (0.8%), as was multi-drug resistant tuberculosis (MDR-TB), also at 0.8%. No resistance to fluoroquinolones (FQ) or kanamycin (KAN) was observed. The INH resistant strain had the katG mutations S315 T, while mutations detected for the MDR-TB were katG S513 T for INH, rpoB S531 L for rifampicin (RIF) and rrs G1484 T for cross-resistance to aminoglycosides/capreomycin (AG/CP).. Molecular analysis confirms transmission of the drug-resistant M. tuberculosis strains. The data suggested that there is homogeneity when it comes to the type of drug resistance and mutation that occurs in the region. This calls for intensified drug resistance surveillance and drug adherence among patients infected with TB.

Topics: Adolescent; Adult; Antitubercular Agents; Capreomycin; Cross-Sectional Studies; Drug Resistance, Bacterial; Female; Gene Frequency; Genotype; Humans; Isoniazid; Kanamycin; Kenya; Male; Microbial Sensitivity Tests; Middle Aged; Mutation; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

Ethiopia is one of 30-high burden multidrug-resistant tuberculosis (MDR-TB) countries globally. The aim of this study was to describe the characteristics of patients with MDR-TB and to investigate risk factors for MDR-TB relative to having drug-susceptible tuberculosis (TB), in northwest Ethiopia. A hospital-based, unmatched case-control study was conducted. Cases were all MDR-TB patients (i.e., resistant to at least rifampicin and isoniazid) who were confirmed by culture and drug-susceptibility testing whilst enrolled on treatment at Gondar University Hospital. Controls were all drug-susceptible tuberculosis (DS-TB) patients who were confirmed by Gene Xpert MTB/RIF at Gondar University Hospital. Univariable and multivariable logistic regression models were used for comparisons, and odds ratios with 95% confidence intervals (CI) were computed to measure the strength of association between the dependent and independent variables. A total of 452 patients (242 MDR-TB and 210 DS-TB) were included in this study. The mean age of the study participants was 33 years (SD ± 14 years). Approximately one-fifth (78, 17%) of all study participants were human immunodeficiency virus (HIV) positive; 21% (51) of cases and 13% (27) of controls. Risk factors associated with MDR-TB were a history of previous TB treatment (Adjusted Odds Ratio (AOR): 83.8; 95% CI: 40.7, 172.5), low educational status (AOR: 5.32; 95% CI: 1.43, 19.81); and ages less than 20 years (AOR: 9.01; 95% CI: 2.30, 35.25) and 21-30 years (AOR: 2.61; 95% CI: 1.02, 6.64). HIV infection was also significantly associated with MDR-TB among new TB patients (AOR: 5.55; 95% CI: 1.17, 26.20). This study shows that clinical and demographic features can be used to indicate higher risks of drug resistance in this setting.

Topics: Adult; Antitubercular Agents; Case-Control Studies; Demography; Ethiopia; Female; HIV Infections; Hospitals; Humans; Isoniazid; Logistic Models; Male; Middle Aged; Mycobacterium tuberculosis; Odds Ratio; Regression Analysis; Rifampin; Risk Factors; Tuberculosis, Multidrug-Resistant; Young Adult

Private physicians in India see and treat more than half of all people with tuberculosis (TB) each year and thus have potential to make significant contributions to TB control. The EQUIP project was designed as a prospective cohort study to assess the potential of private providers to diagnose and appropriately treat drug-resistant TB (DR-TB) in the Central and South districts of Chennai, India.. The private-sector engagement model consisted of free access to rapid diagnostics; choice of free daily or thrice-weekly treatment regimens; support for notification of patients; and patient support including directly observed therapy through EQUIP centers staffed by a community-based interface agency. Data were collected on provider participation; referral results; treatment regimens prescribed; and treatment outcomes.. From October 2015 through June 2017, 227 of the 466 (48.7%) private providers approached referred at least 1 patient to an EQUIP center for evaluation. A total of 2,621 patients received testing and 1,232 (47.0%) were diagnosed with TB. Of those, 727 (59.0%) were bacteriologically confirmed, including 694 (56.3%) using GeneXpert and 33 (2.7%) using smear microscopy. A total of 26 (3.7% of GeneXpert diagnosed) patients were confirmed as rifampicin-resistant cases. EQUIP-related notifications comprised approximately 10% of TB and DR-TB notifications in Chennai during the project period. The project initiated 1,167 (96.8%) drug-sensitive TB patients on treatment. Of those, 691 (59.2%) received standard daily regimens with EQUIP support and 288 (24.7%) received standard intermittent regimens. At the time of writing, 89.4% of 868 drug-susceptible TB patients receiving EQUIP support had treatment success. Of the 26 rifampicin-resistant TB cases notified, 20 (77%) started and continued on second-line treatment; 2 died and 4 were lost to follow-up prior to treatment initiation.. Private providers can make a substantial contribution to detection and appropriate treatment of patients with TB and DR-TB in India when provided with access to rapid diagnostics, support for notification and patient treatment through interface agencies, and free, quality anti-TB drugs.

Topics: Communication; Diagnostic Services; Disclosure; Drug Resistance, Multiple; Humans; India; Physicians; Private Practice; Private Sector; Program Evaluation; Prospective Studies; Public Health; Public-Private Sector Partnerships; Quality Improvement; Referral and Consultation; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

The sites of mycobacterial infection in the lungs of tuberculosis (TB) patients have complex structures and poor vascularization, which obstructs drug distribution to these hard-to-reach and hard-to-treat disease sites, further leading to suboptimal drug concentrations, resulting in compromised TB treatment response and resistance development. Quantifying lesion-specific drug uptake and pharmacokinetics (PKs) in TB patients is necessary to optimize treatment regimens at all infection sites, to identify patients at risk, to improve existing regimens, and to advance development of novel regimens. Using drug-level data in plasma and from 9 distinct pulmonary lesion types (vascular, avascular, and mixed) obtained from 15 hard-to-treat TB patients who failed TB treatments and therefore underwent lung resection surgery, we quantified the distribution and the penetration of 7 major TB drugs at these sites, and we provide novel tools for treatment optimization.. A total of 329 plasma- and 1,362 tissue-specific drug concentrations from 9 distinct lung lesion types were obtained according to optimal PK sampling schema from 15 patients (10 men, 5 women, aged 23 to 58) undergoing lung resection surgery (clinical study NCT00816426 performed in South Korea between 9 June 2010 and 24 June 2014). Seven major TB drugs (rifampin [RIF], isoniazid [INH], linezolid [LZD], moxifloxacin [MFX], clofazimine [CFZ], pyrazinamide [PZA], and kanamycin [KAN]) were quantified. We developed and evaluated a site-of-action mechanistic PK model using nonlinear mixed effects methodology. We quantified population- and patient-specific lesion/plasma ratios (RPLs), dynamics, and variability of drug uptake into each lesion for each drug. CFZ and MFX had higher drug exposures in lesions compared to plasma (median RPL 2.37, range across lesions 1.26-22.03); RIF, PZA, and LZD showed moderate yet suboptimal lesion penetration (median RPL 0.61, range 0.21-2.4), while INH and KAN showed poor tissue penetration (median RPL 0.4, range 0.03-0.73). Stochastic PK/pharmacodynamic (PD) simulations were carried out to evaluate current regimen combinations and dosing guidelines in distinct patient strata. Patients receiving standard doses of RIF and INH, who are of the lower range of exposure distribution, spent substantial periods (>12 h/d) below effective concentrations in hard-to-treat lesions, such as caseous lesions and cavities. Standard doses of INH (300 mg) and KAN (1,000 mg) did not reach therapeutic thresholds in most lesions for a majority of the population. Drugs and doses that did reach target exposure in most subjects include 400 mg MFX and 100 mg CFZ. Patients with cavitary lesions, irrespective of drug choice, have an increased likelihood of subtherapeutic concentrations, leading to a higher risk of resistance acquisition while on treatment. A limitation of this study was the small sample size of 15 patients, performed in a unique study population of TB patients who failed treatment and underwent lung resection surgery. These results still need further exploration and validation in larger and more diverse cohorts.. Our results suggest that the ability to reach and maintain therapeutic concentrations is both lesion and drug specific, indicating that stratifying patients based on disease extent, lesion types, and individual drug-susceptibility profiles may eventually be useful for guiding the selection of patient-tailored drug regimens and may lead to improved TB treatment outcomes. We provide a web-based tool to further explore this model and results at http://saviclab.org/tb-lesion/.

Topics: Adult; Antitubercular Agents; Decision Support Techniques; Disease Progression; Drug Administration Schedule; Drug Dosage Calculations; Drug Resistance, Multiple, Bacterial; Drug Therapy, Combination; Female; Humans; Isoniazid; Kanamycin; Linezolid; Lung; Male; Middle Aged; Pyrazinamide; Retrospective Studies; Rifampin; Tissue Distribution; Treatment Failure; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

Whole genome sequencing (WGS) can elucidate Mycobacterium tuberculosis (Mtb) transmission patterns but more data is needed to guide its use in high-burden settings. In a household-based TB transmissibility study in Peru, we identified a large MIRU-VNTR Mtb cluster (148 isolates) with a range of resistance phenotypes, and studied host and bacterial factors contributing to its spread. WGS was performed on 61 of the 148 isolates. We compared transmission link inference using epidemiological or genomic data and estimated the dates of emergence of the cluster and antimicrobial drug resistance (DR) acquisition events by generating a time-calibrated phylogeny. Using a set of 12,032 public Mtb genomes, we determined bacterial factors characterizing this cluster and under positive selection in other Mtb lineages. Four of the 61 isolates were distantly related and the remaining 57 isolates diverged ca. 1968 (95%HPD: 1945-1985). Isoniazid resistance arose once and rifampin resistance emerged subsequently at least three times. Emergence of other DR types occurred as recently as within the last year of sampling. We identified five cluster-defining SNPs potentially contributing to transmissibility. In conclusion, clusters (as defined by MIRU-VNTR typing) may be circulating for decades in a high-burden setting. WGS allows for an enhanced understanding of transmission, drug resistance, and bacterial fitness factors.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antitubercular Agents; Bacterial Typing Techniques; DNA, Bacterial; Female; Genome, Bacterial; Genomics; Genotype; Humans; Isoniazid; Male; Middle Aged; Mycobacterium tuberculosis; Peru; Polymorphism, Single Nucleotide; Prevalence; Rifampin; Sequence Analysis, DNA; Tuberculosis, Multidrug-Resistant; Whole Genome Sequencing; Young Adult

Topics: Drug Resistance, Multiple, Bacterial; Female; Humans; Incidence; Male; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Drug resistant tuberculosis is a major public health problem in Morocco and worldwide. Treatment outcome of drug resistant tuberculosis is poor and requires a long period of treatment with many toxic and expensive antituberculosis drugs. The aim of this study is to evaluate treatment outcomes of drug resistant tuberculosis and to determine predictors of poor treatment outcomes in a large region of Morocco.. It is a multi-centric observational cohort study conducted from January 01, 2014 to January 01, 2016. A questionnaire was established to collect data from clinical charts of patients with confirmed resistant TB. The study was carried out in all the 11 centers located in the Rabat-Salé-Kénitra region of Morocco where drug resistant tuberculosis is treated. Treatment outcomes were reported and the definitions and classifications of these outcomes were defined according to the WHO guidelines. Univariate and multivariate logistic regression were conducted to determine factors associated with poor drug resistant tuberculosis treatment outcomes in Morocco.. In our study, 101 patients were treated for drug resistant tuberculosis between January 01, 2014 and January 01, 2016. Patients' age ranged from 9.5 to70 years; 72patients (71.3%) were male and 80 patients (79.2%) were living in urban areas. Thirty two patients were smokers, 74 patients had multidrug-resistant tuberculosis, 25 patients had rifampicin resistance and 2 patients had isoniazid resistance. Treatment outcomes of tuberculosis patients were as follows: 45 patients were cured (44.5%), 9 completed treatment (8.9%), 5 patients died before completing the treatment, 35 patients were lost to follow up (34.6%) and 7 patients had treatment failure. In the multivariate analysis, being a smoker is an independent risk factor for poor treatment outcomes, (p-value = 0.015, OR = 4.355, IC [1.327-14.292]).. Treatment success outcomes occurred in more than half of the cases, which is lower than the World Health Organization target of at least a 75% success rate. A significant number of patients abandoned their treatment before its completion. These dropouts are a serious public health hazard that needs to be addressed urgently.

Topics: Adolescent; Adult; Aged; Antitubercular Agents; Child; Cohort Studies; Female; Humans; Isoniazid; Male; Middle Aged; Morocco; Prospective Studies; Rifampin; Risk Factors; Treatment Failure; Treatment Outcome; Tuberculosis, Multidrug-Resistant; World Health Organization; Young Adult

To evaluate the rapid diagnosis of multidrug-resistant tuberculosis, by using a commercial line probe assay for rifampicin and isoniazid detection (LPA-plus), in the routine workflow of a tuberculosis reference laboratory.. The LPA-plus was prospectively evaluated on 341 isolates concurrently submitted to the automated liquid drug susceptibility testing system.. Among 303 phenotypically valid results, none was genotypically rifampicin false-susceptible (13/13; 100% sensitivity). Two rifampicin-susceptible isolates harboured rpoB mutations (288/290; 99.3% specificity) which, however, were non-resistance-conferring mutations. LPA-plus missed three isoniazid-resistant isolates (23/26; 88.5% sensitivity) and detected all isoniazid-susceptible isolates (277/277; 100% specificity). Among the 38 (11%) invalid phenotypic results, LPA-plus identified 31 rifampicin- and isoniazid-susceptible isolates, one isoniazid-resistant and six as non-Mycobacterium tuberculosis complex.. LPA-plus showed excellent agreement (≥91%) and accuracy (≥99%). Implementing LPA-plus in our setting can speed up the diagnosis of multidrug-resistant tuberculosis, yield a significantly higher number of valid results than phenotypic drug susceptibility testing and provide further information on the drug-resistance level.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antitubercular Agents; Child; Child, Preschool; DNA, Bacterial; Early Diagnosis; Female; Humans; Infant; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Molecular Diagnostic Techniques; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Phenotype; Prospective Studies; Reproducibility of Results; Rifampin; Sensitivity and Specificity; Time Factors; Tuberculosis, Multidrug-Resistant; Young Adult

There were an estimated 580,000 new cases of multidrug/rifampicin resistant TB (DR-TB) in 2015, and only 20% were initiated on treatment. This study explored health system and patient factors associated with initiation and timeliness of treatment among DR-TB patients in Nigeria, ranked 4th globally for estimated TB cases in 2015.. A retrospective cohort study using 2015 diagnosis and treatment data from the Nigerian TB program electronic records examined "treatment ever received" (yes/no) and "treatment within 30 days" (yes/no). We compared health system and patient characteristics using binomial logistic regression, while controlling for confounders.. Of 996 patients diagnosed nationwide in 2015 (aged 0-87 years, median 34), 47.8% were never treated. Of those treated (n = 520), 51.2% were treated within the 30 days prescribed in the National treatment guideline. Healthcare facility locations were significantly associated with ever receiving treatment and timely treatment. Predictors of timely treatment at the national level also included level of care and patient treatment history. The South-West zone, where DR-TB programs started, showed overall better access to DR-TB healthcare.. Healthcare facility geographic locations were significantly associated with treatment initiation and timeliness. Significant regional differences in access to DR-TB care in Nigeria persist, reflecting uneven contexts for national DR-TB treatment rollout.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antitubercular Agents; Child; Child, Preschool; Female; Healthcare Disparities; Humans; Infant; Infant, Newborn; Male; Middle Aged; Nigeria; Retrospective Studies; Rifampin; Rural Health Services; Time Factors; Time-to-Treatment; Tuberculosis, Multidrug-Resistant; Urban Health Services; Young Adult

Most studies assessing drug resistant tuberculosis (DRTB) in human immunodeficiency virus (HIV) co-infected patients in India have used conventional culture- based systems to diagnose DRTB that have a longer turnaround time leading to risk of amplification of resistance to an empirical regimen. We determined the prevalence of DRTB amongst people living with HIV (PLHIV) using the line probe assay and determined risk factors associated with the presence of multi drug resistant tuberculosis (MDRTB).. A Cross-sectional study was undertaken at Poona Hospital and Research Center (PHRC) and the Institute of Infectious Diseases, two tertiary level private care centers in Pune, India. Consenting PLHIV with confirmed Pulmonary TB (PTB) and/or extra-pulmonary TB (EPTB) diagnosed based on detection of Mycobacterium TB by line probe assay (Geno Type MTBDRplus version 2) on clinical specimens were included. Those with documented past history of DRTB were excluded. Resistance against anti-TB drugs was determined by the same assay. The prevalence of any form of drug resistant TB (DRTB), MDRTB, Rifampicin resistant TB (RRTB) and Isoniazid (INH) mono-resistant TB were determined as the proportion of these amongst all included PLHIV-TB. A multivariate analysis was conducted to determine risk factors that were statistically associated with MDRTB, DRTB, RRTB and INH mono-resistant TB.. Two hundred PLHIV were recruited. The prevalence (95% CI) of MDRTB, INH mono- resistance and RR resistance was 12.5% (7.9-17.1%), 9% (6.9-11.2%) and 2.5% (1.4-3.6%), respectively. The prevalence (95% CI) of MDRTB among new and relapsed patients was 8.8% (6.5-11.1%) and 23.1% (17.2-28.9%), respectively. Tuberculosis relapse was the only factor significantly associated with MDRTB, DRTB and INH mono-resistant TB.. We document a high prevalence of drug resistance to anti-TB drugs including MDRTB among PLHIV in our setting using Geno Type MTBDRplus directly on clinical specimens. This validates the WHO recommendation of performing routine rapid molecular resistance testing prior to initiating anti-TB treatment among all PLHIV with presumptive TB. Using rapid molecular testing especially Geno Type MTBDRplus (that detects resistance to INH and Rifampicin simultaneously) reduces the turn-around time helping in optimizing treatment.

Topics: Adolescent; Adult; AIDS-Related Opportunistic Infections; Antitubercular Agents; Child; Cross-Sectional Studies; Female; HIV Infections; Humans; India; Isoniazid; Male; Middle Aged; Prevalence; Rifampin; Risk Factors; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

In Myanmar, Rifampicin resistant tuberculosis (RR-TB, a proxy for Multi-drug resistant TB) case detection is very low. Our study objectives were to assess the proportion of eligible TB patients who had not undergone RR-TB testing (Xpert-MTB/Rif tests) in Bago Region, Myanmar and to understand the reasons and solutions for non-testing. We conducted a mixed-methods study involving analysis of routinely collected programme data followed by key informant interviews (KIIs) with 32 health care providers. From October 2016 to March 2017, of the 2,331 eligible patients, 1,066 (46%) had not undergone Xpert-MTB/Rif testing. Patients from townships without Xpert-MTB/Rif testing facilities, new TB patients, patients whose HIV status was negative or unknown and extra pulmonary TB patients were less likely to undergo Xpert-MTB/Rif testing. From the health care providers' perspective, the most common reasons for non-testing were: (a) lack of awareness of the eligibility criteria; (b) difficulties in collecting sputum and transportation from eligible patients to the testing sites. We conclude that nearly half of eligible patients were not tested for RR-TB. Training of health care providers about the latest eligibility criteria and improvement in sputum collection and transportation systems particularly for townships without Xpert-MTB/Rif testing facilities are required to improve RR-TB testing.

Topics: Adolescent; Adult; Early Diagnosis; Female; Health Services Accessibility; Humans; Male; Middle Aged; Myanmar; Mycobacterium tuberculosis; Qualitative Research; Retrospective Studies; Rifampin; Rural Health; Tuberculosis, Multidrug-Resistant; Young Adult

Topics: Antitubercular Agents; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Practice Guidelines as Topic; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant; World Health Organization

Xpert MTB/RIF assay rapidly diagnoses rifampicin resistance, enabling early initiation of second-line tuberculosis (TB) treatment. However, the impact of an earlier multidrug-resistant TB (MDR-TB) diagnosis on treatment outcomes is unknown.. To compare MDR-TB treatment outcomes in cases diagnosed with smear/culture and Xpert.. This was a retrospective cohort study with cohorts defined by the diagnostic assay used in presumptive TB cases. Data were extracted from a drug-resistant (DR)-TB register including cases from January 2012 to June 2014. Treatment outcomes were assessed at recorded endpoints or after 2 years for those completing treatment.. A total of 718 cases were enrolled into the study. Cure rates were 43.4% (n=158) for the smear/culture cohort and 33.5% (n=118) for the Xpert cohort (p<0.01). Xpert diagnosis (adjusted risk ratio (aRR) 0.65; p=0.02) and male gender (aRR 0.66; p=0.04) were associated with cure outcome. Xpert diagnosis increased time to sputum culture conversion from 4 to 5 months (log-rank test p=0.01). Time to treatment initiation was not associated with treatment success in logistic regression analysis.. Despite rapid treatment initiation, MDR-TB treatment outcomes were poorer in patients diagnosed with Xpert MTB/RIF assay than in the smear/culture cohort, and they were also poorer in men than in women. Additional studies are required to assess possible factors influencing DR-TB outcomes.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antibiotics, Antitubercular; Drug Resistance, Multiple, Bacterial; Female; Follow-Up Studies; Humans; Logistic Models; Male; Middle Aged; Nucleic Acid Amplification Techniques; Reagent Kits, Diagnostic; Retrospective Studies; Rifampin; South Africa; Time-to-Treatment; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Young Adult

Multidrug-resistant Mycobacterium tuberculosis (MDR-TB) is a severe health threat to human beings; however, the epidemic and molecular characteristics exist along with the change in the geographic environment and genealogy. Jiangxi province is located in southeast China, which is a high-MDR-TB burden area. Rifampin (RIF) and isoniazid (INH) are the most important first-line anti-tuberculosis drugs. The major drug target genes include rpoB for RIF and katG, inhA, and ahpC for INH. To determine the frequency and distribution of mycobacterial mutations in these genes, we sequenced specific genes of M. tuberculosis that are associated with resistance to RIF and INH in 157 phenotypic MDR isolates. At the same time, RD105 DTM-PCR and 15 loci MIRU-VNTR were performed to demonstrate the genetic lineage. It was shown that the Beijing genotype was predominant (84.1%) among these strains. The results also showed mutations within the 81 bp core region of rpoB in 93.6% of strains and mutations in a structural gene (katG) and two regulatory regions (the promoter of inhA and intergenic region of oxyR-ahpC) were shown in 88.5% of phenotypic MDR isolates. There were no significant differences in codon mutations between the Beijing and non-Beijing genotypes, as well as the clustered and no-clustered strains. The most prevalent mutations involved in RIF and INH were Ser531Leu in rpoB (55.4%) and Ser315Thr in KatG (56.1%), respectively. There was no significant difference in RIF and INH resistance between MDR-TB and other drug-resistant tuberculosis (DR-TB). The results demonstrated that some MDR-TB patients are predicted to have recent transmission.

Topics: Adult; Antitubercular Agents; Bacterial Proteins; Catalase; China; DNA-Directed RNA Polymerases; DNA, Bacterial; Female; Genes, Bacterial; Genotype; Genotyping Techniques; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Molecular Epidemiology; Molecular Typing; Mutation; Mycobacterium tuberculosis; Prevalence; Promoter Regions, Genetic; Rifampin; Tuberculosis, Multidrug-Resistant

This case report has tried to highlight the ease and benefit of Gene-Xpert testing in difficult to diagnose patient with sputum smear negative pulmonary tuberculosis. Early treatment of tuberculosis is usually delayed by lack of rapid and accurate diagnostic modalities, especially in resource-limited settings like ours. Gene-Xpert is a rapid test based on real time PCR assay and molecular technology for the detection of Mycobacterium tuberculosis. It is highly sensitive tool and enables simultaneous detection of rifampicin resistance within short period of time i,e. <2hrs. It has distinct advantage of providing same-day diagnosis which could potentially limit loss to follow up during diagnostic evaluation of smear negative tuberculosis patients. Keywords: Gene-Xpert; pulmonary tuberculosis; sputum microscopy.

Topics: Antitubercular Agents; False Negative Reactions; Humans; Male; Middle Aged; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Radiography, Thoracic; Rifampin; Sputum; Tomography, X-Ray Computed; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

世界卫生组织于2018年8月发布了"关于耐多药和利福平耐药结核病治疗重大变化"的文件，将长程耐多药结核病治疗方案推荐使用的药物分组进行了更新，重新分组后更加方便实用，增加了患者的依从性和疗效，但也出现价格昂贵、药物无法获得、注射类药物的取舍、组合方案的安全性及患者接受程度等问题。虽然这种分组在我国的实施会遇到不少问题，但对我国耐多药结核病治疗指南的制定提供了重要的参考价值。.

Topics: Antitubercular Agents; Humans; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

耐多药或利福平耐药结核病的治疗是我国乃至全球结核病控制的难点与挑战。本文在归纳结核病化疗疗程特点的基础上，分析了耐多药或利福平耐药结核病的长程（疗程≥20个月）和短程（疗程9~12个月）化疗方案的利弊，介绍长程和短程化疗方案的制定、方案特点及适应证等，以期为耐多药或利福平耐药结核病患者化疗方案的合理选择、短程化疗方案的应用与推广等提供依据。.

Topics: Antitubercular Agents; Humans; Isoniazid; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Drug-resistant tuberculosis (TB), especially multidrug-resistant TB (MDR-TB), poses a threat to public health. While standard surveillance focuses on Rifampicin and/or Isoniazid resistance, little is known about other resistance patterns. This study aims to identify predominant drug resistance (DR) patterns in Germany and risk factors associated with them in order to inform diagnostic and treatment strategies.. Case-based TB surveillance data notified in Germany from 2008-2017 were utilized to investigate DR and MDR-TB patterns for Isoniazid (H), Rifampicin (R), Pyrazinamide (Z), Ethambutol (E), and Streptomycin (S). Predominant patterns were further analyzed stratified by sex, age, country of birth, prior TB, and disease site. Multivariable logistic regression was conducted to determine risk factors associated with any resistance, MDR-TB, and complete HRZES resistance.. 26,228 cases with complete DST results were included in the study, among which 3,324 cases had any DR (12.7%). Four patterns were predominant, representing about ¾ of all cases with any resistance (S: 814 [3.1%]; H: 768 [2.9%]; HS: 552 [2.1%]; Z: 412 [1.6%]). High proportions of S and H resistances were found among both German and foreign-born populations, especially those born in Eastern Europe, and were unexpectedly high among children (H: 4.3%; S: 4.6%). Foreign-born cases had significantly higher proportion of any resistance (16.0%) and MDR-TB (3.3%) compared to German-born cases (8.3% and 0.6%). Of 556 MDR-TB cases, 39.2% showed complete HRZES resistance. Logistic regression revealed having prior TB and being foreign-born as consistently strong risk factors for any DR, MDR-TB, and complete HRZES resistance.. DR patterns observed in Germany, particularly for MDR-TB were more complex than expected, highlighting the fact that detailed drug-testing results are crucial before incorporating HRZES drugs in MDR-TB treatment. Furthermore, the relatively high rate of H-resistance in Germany provides strong rationale against the use of only H-based preventive therapy for LTBI.

Topics: Adolescent; Adult; Antitubercular Agents; Child; Child, Preschool; Drug Resistance, Multiple, Bacterial; Emigrants and Immigrants; Ethambutol; Female; Germany; Humans; Infant; Isoniazid; Logistic Models; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Prevalence; Public Health Surveillance; Pyrazinamide; Rifampin; Risk Factors; Streptomycin; Tuberculosis, Multidrug-Resistant

Both passive and active surveillance of drug resistance have an important role in tuberculosis (TB) control program. Surveillance data are important to estimate the magnitude of drug resistance TB, to know the trend of the disease, assess the performance of the program, and to forecast diagnosis and treatment supplies. Therefore, this study aimed to determine the prevalence and the proportion of drug resistant tuberculosis in Ethiopia based on passively collected data.. A cross-sectional study was conducted at the National Tuberculosis Reference Laboratory and seven Regional TB laboratories in Ethiopia on a retrospective data collected from July 2017 to June, 2018. Data were collected by standardized checklist from TB culture laboratory registration book. Percentage of recovery rate, contamination rate, and prevalence of drug resistance TB were determined by Statistical Package for Social Science (SPSS) version 23.. Of 10 134 TB suspected individuals included into this analysis, 1183 (11.7%) were culture positive. The overall contamination proportion was 5.3% and nontuberculous mycobacteria proportion was 0.98%. First-line drug susceptibility test was performed for 329 Mycobacterium tuberculosis complex isolates, and the proportion of resistance was 5.7 and 6.3% for isoniazid and rifampicin respectively. The proportion of multidrug-resistant tuberculosis (MDR-TB) was 4.3% in new patients, while 6.7% in previously treated patients. However, there was no category for 0.6% patients, and the overall proportion of MDR-TB was 11.6%.. The result of this study indicated that MDR-TB is a serious public health problem in Ethiopia. Thus, strengthen prevention and control program is vital to halt the burden of drug resistant TB in the country.

Topics: Antitubercular Agents; Cross-Sectional Studies; Ethiopia; Female; Humans; Isoniazid; Male; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant

The diagnosis of osteoarticular tuberculosis (TB) remains challenging and results in under- or over-diagnosis. The aim of the present study was to evaluate performance of the novel next-generation Xpert MTB/RIF Ultra (Xpert Ultra) in comparison to culture and Xpert MTB/RIF (Xpert) for osteoarticular TB diagnosis in high burden settings.. Osteoarticular TB suspected cases were enrolled consecutively during June 2017 to June 2018 at Beijing Chest Hospital and their pus specimens were subjected to smear, culture, Xpert and Xpert Ultra. Drug susceptibility testing (DST) was conducted for all of the recovered isolates. The performances of Xpert Ultra and Xpert were evaluated using composite reference standard (CRS) as gold standard, which included clinical, laboratory, histopathological, radiological and ≥6 months' follow-up data.. In total, 186 patients were recruited, and 132 of them were diagnosed with osteoarticular TB according to CRS. The direct head-to-head performance comparison for M. tuberculosis detection showed that Xpert Ultra (90.91%, 120/132) produced a higher sensitivity than Xpert (78.79%, 104/132, P = 0.006) and culture (39.39%, 52/132, P < 0.001). When Xpert Ultra outcomes were integrated, the percentage of confirmed osteoarticular TB case increased from 84.09% (111/132) to 93.94% (124/132). The specificities of Xpert and Xpert Ultra were 100% (34/34) and 97.06% (33/34), respectively. Both Xpert Ultra and Xpert accurately identified all of the 9 rifampicin (RIF)-resistant and 38 RIF-sensitive cases defined by phenotypic DST. Therefore, Xpert Ultra was 100% concordant with phenotypic DST for the detection of RIF resistance.. Xpert Ultra detected significantly more osteoarticular TB cases than Xpert or culture, making it a useful tool for rapid diagnosis of osteoarticular TB.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Drug Resistance, Bacterial; Female; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant; Tuberculosis, Osteoarticular; Young Adult

The diagnoses of active smear negative PTB, remains difficult. As a result, treatment is often carried out empirically relaying on clinical criteria. The distribution and magnitude of smear negative PTB, smear negative MDR-TB and associated factors in the same day diagnosis strategy are not clearly known in the study area. Therefore, this study aimed to determine the prevalence of TB, MDR-TB and associated risk factors among presumptive smear negative pulmonary tuberculosis patients in Addis Ababa, Ethiopia.. Analytic cross sectional study design was used. A total of 418 smear negative presumptive pulmonary TB patients were enrolled from selected health facilities since August 01, 2017 to January 5, 2018. Sputum samples were examined by Ziehl Neelsen microscopy, Xpert MTB/RIF assay and Culture. Drug susceptibility testing was performed by line probe assay and BACTEC MGIT 960 system. These laboratory tests were performed in Ethiopian Public Health Institute, National TB Reference Laboratory. Data was analyzed by SPSS Ver.20.. From the total of 418 enrolled patients, 27 (6.5%) were Xpert MTB/ RIF and 26 (6.4%) were culture confirmed smear negative PTB patients. The positivity rate among male and female was 10.2 and 3.5% (p = 0.005) respectively. From 26 culture positive isolates 3 (11.54%) were MDR TB; from MDR-TB confirmed isolates 2/23 (8.7%) were among new and 1/3 (33.3%) was among retreatment smear negative presumptive pulmonary TB patients. All Rifampicin resistant smear negative pulmonary TB isolates by Xpert MTB/ RIF assay were found to be MDR TB and 7/26 (26.9%) isolates were INH mono resistant. History of migration found to be a potential factor for developing smear negative pulmonary TB.. In this study a significant proportion of smear negative pulmonary TB was diagnosed. Furthermore, a high smear negative multi drug resistant (MDR) TB and other mono drug resistant TB prevalence was confirmed. Due to the limitations of smear microscopy which is used as a primary diagnostic tool, these TB strains are missed to be diagnosed and transmission continues in the community.

Topics: Adolescent; Adult; Aged; Child; Child, Preschool; Comorbidity; Cross-Sectional Studies; Ethiopia; Female; Humans; Infant; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Prevalence; Rifampin; Risk Factors; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Since in low incidence TB countries population migration and complex treatment of drug-resistant tuberculosis (DR-TB) patients are major issues, we aimed to analyse patient risk factors associated with the incidence of poor outcome of TB treatment among DR-TB patients in the Netherlands.. This retrospective cohort study included adult patients with confirmed DR-TB treated from 2005 to 2015. We obtained data from a nationwide exhaustive registry of tuberculosis patients in the Netherlands. Predictors for unsuccessful TB treatment (defaulted and failed treatment) and TB-associated mortality were analysed using multivariate logistic regression.. Among 10,303 registered TB patients, 545 patients with DR-TB were analysed. Six types of DR-TB were identified from the included patients, i.e. isoniazid mono- or poly-resistance (68%); rifampicin mono- or poly-resistance (3.1%); pyrazinamide mono-resistance (8.3%); ethambutol mono-resistance (0.1%); multidrug-resistance (18.9%); and extensively drug-resistance (0.7%). The majority of patients were foreign-born (86%) and newly diagnosed TB (89%) patients. The cumulative incidence of unsuccessful treatment and mortality were 5 and 1%, respectively. Among all DR-TB cases, patients with Multi Drug-Resistant Tuberculosis (MDR-TB) (OR 4.43; 95%CI 1.70-11.60) were more likely to have unsuccessful treatment, while miliary and central nervous system TB (OR 15.60; 95%CI 2.18-111.52) may also be predictors for TB mortality. Additionally, patients with substance abuse and homelessness tend to have unsuccessful treatment.. In recent years, we identified a low incidence of DR-TB as well as the poor outcome of DR-TB treatment. The majority of cases were primary drug-resistant and foreign-born. To further improve treatment outcome, special attention should be given to the high-risk DR-TB patients.

Topics: Adult; Aged; Antitubercular Agents; Ethambutol; Humans; Incidence; Isoniazid; Logistic Models; Middle Aged; Netherlands; Pyrazinamide; Registries; Retrospective Studies; Rifampin; Risk Factors; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Young Adult

To determine the prevalence of resistance to rifampicin alone; rifampicin and isoniazid, and second-line anti-TB drugs among sputum smear-positive tuberculosis patients in Zimbabwe.. A health facility-based cross-sectional survey.. In total, 1114 (87.6%) new and 158 (12.4%) retreatment TB patients were enrolled. MTB was confirmed by Xpert MTB/RIF among 1184 (93%) smear-positive sputum samples. There were 64 samples with Xpert MTB/RIF-determined rifampicin resistance. However, two were rifampicin susceptible on phenotypic drug susceptibility testing. The prevalence of RR-TB was [4.0% (95% CI, 2.9, 5.4%), n=42/1043) and 14.2% (95% CI, 8.9, 21.1%; n=20/141) among new and retreatment patients, respectively. The prevalence of MDR-TB was 2.0% (95% CI, 1.3, 3.1%) and 6.4% (95% CI, 2.4, 10.3%) among new and retreatment TB patients, respectively. Risk factors for RR-TB included prior TB treatment, self-reported HIV infection, travel outside Zimbabwe for ≥one month (univariate), and age <15 years. Having at least a secondary education was protective against RR-TB.. The prevalence of MDR-TB in Zimbabwe has remained stable since the 1994 subnational survey. However, the prevalence of rifampicin mono-resistance was double that of MDR-TB.

Topics: Adolescent; Adult; Aged; Anti-Bacterial Agents; Child; Cross-Sectional Studies; Drug Resistance, Bacterial; Female; Health Facilities; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Prevalence; Rifampin; Risk Factors; Sensitivity and Specificity; Sputum; Surveys and Questionnaires; Tuberculosis, Multidrug-Resistant; Young Adult; Zimbabwe

Genitourinary tuberculosis (GUTB) accounts for up to 40% of extrapulmonary tuberculosis cases. Rapid tests for GUTB are urgently needed because it is often associated with delayed health-care seeking, leading to serious consequences. This study evaluated the performance of the Xpert MTB/RIF assay in the rapid diagnosis of urinary tract tuberculosis (UTB) and rifampicin-resistant tuberculosis with urine specimens. In all, 302 patients were included from four hospitals in China. Suspected UTB patients were tested with Xpert, smear, and MGIT 960 culture. Drug susceptibility testing (DST) was conducted for culture-positive cases. The performance of the assays was evaluated against MGIT 960 culture and a composite reference standard (CRS). Among all participants, 150 (49.7%) had CRS-positive UTB, of whom 36 (24.0%) were culture-confirmed. Against culture, Xpert and smear achieved a sensitivity of 94.4% (95% CI: 81.3-99.3%) and 22.2% (95% CI: 10.1-39.2%), respectively. Against CRS, the sensitivity of Xpert, smear and culture was 41.3% (95% CI: 33.4-49.7%), 7.3% (95% CI: 3.7-12.7%), and 24.0% (95% CI: 17.4-31.6%). Xpert had better performance than smear and culture in detecting UTB from urine samples and could be considered for the diagnosis of UTB. Moreover, Xpert showed better performance than MGIT 960-based DST using urine culture.

Topics: Adult; Aged; Aged, 80 and over; Antibiotics, Antitubercular; Drug Resistance, Bacterial; Female; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Female Genital; Tuberculosis, Male Genital; Tuberculosis, Multidrug-Resistant; Young Adult

2018 World Health Organization (WHO) guidelines for the treatment of isoniazid (H)-resistant (Hr) tuberculosis recommend a four-drug regimen: rifampicin (R), ethambutol (E), pyrazinamide (Z) and levofloxacin (Lfx), with or without H ([H]RZE-Lfx). This is used once Hr is known, such that patients complete 6 months of Lfx (≥6[H]RZE-6Lfx). This cohort study assessed the impact of fluoroquinolones (Fq) on treatment effectiveness, accounting for Hr mutations and degree of phenotypic resistance.. This was a retrospective cohort study of 626 Hr tuberculosis patients notified in London, 2009-2013. Regimens were described and logistic regression undertaken of the association between regimen and negative regimen-specific outcomes (broadly, death due to tuberculosis, treatment failure or disease recurrence).. Of 594 individuals with regimen information, 330 (55.6%) were treated with (H)RfZE (Rf=rifamycins) and 211 (35.5%) with (H)RfZE-Fq. The median overall treatment period was 11.9 months and median Z duration 2.1 months. In a univariable logistic regression model comparing (H)RfZE with and without Fqs, there was no difference in the odds of a negative regimen-specific outcome (baseline (H)RfZE, cluster-specific odds ratio 1.05 (95% CI 0.60-1.82), p=0.87; cluster NHS trust). Results varied minimally in a multivariable model. This odds ratio dropped (0.57, 95% CI 0.14-2.28) when Hr genotype was included, but this analysis lacked power (p=0.42).. In a high-income setting, we found a 12-month (H)RfZE regimen with a short Z duration to be similarly effective for Hr tuberculosis with or without a Fq. This regimen may result in fewer adverse events than the WHO recommendations.

Topics: Adolescent; Adult; Aged; Antitubercular Agents; Drug Therapy, Combination; Duration of Therapy; Ethambutol; Female; Fluoroquinolones; Humans; Isoniazid; Levofloxacin; Logistic Models; London; Male; Middle Aged; Practice Guidelines as Topic; Pyrazinamide; Recurrence; Retrospective Studies; Rifampin; Treatment Failure; Tuberculosis, Multidrug-Resistant; World Health Organization; Young Adult

Mycobacterium tuberculosis protein-tyrosine-phosphatase B (MptpB) is a secreted virulence factor that subverts antimicrobial activity in the host. We report here the structure-based design of selective MptpB inhibitors that reduce survival of multidrug-resistant tuberculosis strains in macrophages and enhance killing efficacy by first-line antibiotics. Monotherapy with an orally bioavailable MptpB inhibitor reduces infection burden in acute and chronic guinea pig models and improves the overall pathology. Our findings provide a new paradigm for tuberculosis treatment.

Topics: Animals; Antitubercular Agents; Bacterial Proteins; Drug Design; Drug Resistance, Multiple; Female; Guinea Pigs; Macrophages; Male; Models, Molecular; Molecular Structure; Mycobacterium tuberculosis; Protein Conformation; Protein Tyrosine Phosphatases; Structure-Activity Relationship; Tuberculosis, Multidrug-Resistant

Diagnosis of drug-resistant tuberculosis predominantly relies on culture-based drug susceptibility testing, which take weeks to produce a result and a more time-efficient alternative method is multiplex allele-specific PCR (MAS-PCR). Also, understanding the role of mutations in causing resistance helps better drug designing.. To evaluate the ability of MAS-PCR in the detection of drug resistance and to understand the mechanism of interaction of drugs with mutant proteins in Mycobacterium tuberculosis.. Detection of drug-resistant mutations using MAS-PCR and validation through DNA sequencing. MAS-PCR targeted five loci on three genes, katG 315 and inhA -15 for the drug isoniazid (INH), and rpoB 516, 526, and 531 for rifampicin (RIF). Furthermore, the sequence data were analyzed to study the effect on interaction of the anti-TB drug molecule with the target protein using in silico docking.. We identified drug-resistant mutations in 8 out of 114 isolates with 2 of them as multidrug-resistant TB using MAS-PCR. DNA sequencing confirmed only six of these, recording a sensitivity of 85.7% and specificity of 99.3% for MAS-PCR. Molecular docking showed estimated free energy of binding (ΔG) being higher for RIF binding with RpoB S531L mutant. Codon 315 in KatG does not directly interact with INH but blocks the drug access to active site.. We propose DNA sequencing-based drug resistance detection for TB, which is more accurate than MAS-PCR. Understanding the action of resistant mutations in disrupting the normal drug-protein interaction aids in designing effective drug alternatives.

Topics: Alleles; Antitubercular Agents; Bacterial Proteins; Catalytic Domain; Drug Resistance, Multiple, Bacterial; Humans; India; Isoniazid; Microbial Sensitivity Tests; Molecular Docking Simulation; Multiplex Polymerase Chain Reaction; Mutation; Mycobacterium tuberculosis; Rifampin; Sequence Analysis, DNA; Tuberculosis, Multidrug-Resistant

Nearly 20,000 people were diagnosed with multi-drug and rifampicin-resistant tuberculosis (MDR/RR-TB) in South Africa in 2015, yet only one-half of the patients who start treatment are expected to have a successful outcome. There is increasing evidence of the effectiveness and safety of new drug regimens containing bedaquiline for MDR/RR-TB; however, whether they are affordable for high-burden, limited-resource settings is uncertain.. Our objective was to determine the incremental cost effectiveness of a bedaquiline-based regimen for MDR/RR-TB treatment in South Africa compared with the standard kanamycin-based regimen.. We established a Markov model for ambulatory treatment of MDR/RR-TB in a high-HIV prevalence setting, parameterized using clinical outcomes from the South African National TB Programme (SA NTP) before (2012-2014) and after (2015-2016) bedaquiline roll-out. The effectiveness of treatment was evaluated in disability-adjusted life-years (DALYs). Ingredient costs from the provider's perspective were collected in 2016 South African Rand and converted to $US, including bedaquiline at $US675.23 per 6-month treatment course. Culture conversion rates were derived from the phase IIb trial of bedaquiline, and disability adjustments were adapted from published literature. Costs and effectiveness were discounted at 3%.. For non-bedaquiline regimens, the total expected cost over the 10-year time horizon for a patient with MDR/RR-TB was $US4439 with disability-adjusted survival of 5.1 years. Replacing capreomycin with bedaquiline in patients who failed MDR/RR-TB treatment and required treatment for extensively drug-resistant (XDR-TB) resulted in cost savings ($US4356; 1.8% less) and similar effectiveness (0.02 DALYs averted). As a result, the standard regimen (no bedaquiline) was dominated. Replacing kanamycin with bedaquiline to provide all patients with MDR/RR-TB access to bedaquiline cost $US4647 (4.3% more) and averted 0.17 DALYs compared with the no bedaquiline regimen. The incremental cost-effectiveness ratio was $US1242/DALY averted.. Markov modelling indicates providing bedaquiline for all patients with MDR/RR-TB could increase the 24-month treatment success rate in South Africa from 56.3% using the current regimen to 60.6%, at a cost $US2.6 million over a 10-year horizon, less than 1% of the estimated $US425 million SA NTP annual budget.

Topics: Antitubercular Agents; Coinfection; Cost-Benefit Analysis; Diarylquinolines; Drug Costs; Health Care Costs; HIV Infections; Humans; Markov Chains; Rifampin; South Africa; Time Factors; Treatment Outcome; Tuberculosis, Multidrug-Resistant

The number of multidrug-resistant tuberculosis (MDR-TB) cases is rising worldwide. The present investigation aimed to evaluate, using the GenoType. A total of 319 Mycobacterium tuberculosis isolates sent to the National Tuberculosis Reference Laboratory between 2013 and 2015 were subjected to GenoType. The most frequent mutations observed were rpoBS531L (67.2%) and katGS315T1/2 (66.5%). Isolates with inhA gene mutation, katG gene mutation, and dual mutations in katG and inhA had MICs ranging from 0.5-1μg/mL, 2-10μg/mL and ≥12μg/mL, respectively.. In Morocco, 66.5% and 76.7% of M. tuberculosis strains carried mutations causing high-level resistance to INH and RIF, respectively.

Topics: Adult; Antitubercular Agents; Bacterial Proteins; Bacterial Typing Techniques; Drug Resistance, Multiple, Bacterial; Female; Genotype; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Morocco; Mutation; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant; Young Adult

The Xpert MTB/RIF test (Cepheid, Sunnyvale, CA) can simultaneously detect the Mycobacterium tuberculosis (MTB) complex DNA and rifampicin (RFP) resistance and can rapidly determine RFP resistance and predict multidrug-resistant tuberculosis (MDR-TB). In this study, we analyzed clinical examination results of a hospital specializing in TB treatment in Wuhan, Hubei, China, and examined the use of traditional culture and drug-sensitive test (DST) results as a gold standard to assess the diagnosis value of the Xpert MTB/RIF test in RFP resistance and MDR-TB.. A total of 2,910 specimens were received in the Mycobacteriology Laboratory, Wuhan Pulmonary Hospital, for Xpert MTB/RIF testing between December 2013 and December 2014. After the results were reviewed by exclusion criteria, 1,066 Xpert test results were eligible for our study. We then compared the Xpert test results with sputum acid-fast bacilli staining, cultures, and DST results.. In total, Xpert correctly identified 96.71% (147/152) RFP-resistant TB and 98.25% (898/914) RFP-sensitive TB specimens. Of the 147 RFP-resistant TB specimens detected by Xpert, 122 MDR-TB (82.99%) were identified by traditional culture and DST techniques.. Xpert can simultaneously detect MTB and RFP resistance with high sensitivity and specificity. Thus, Xpert testing aids in saving a considerable amount of time in the diagnosis and treatment of MDR-TB.

Topics: Anti-Bacterial Agents; Antibiotics, Antitubercular; China; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Drug susceptibility testing (DST) of clinical isolates of Mycobacterium tuberculosis is critical in treating tuberculosis. We demonstrate the possibility of using a microbial sensor to perform DST of M. tuberculosis and shorten the time required for DST.. The sensor is made of an oxygen electrode with M. tuberculosis cells attached to its surface. This sensor monitors the residual oxygen consumption of M. tuberculosis cells after treatment with anti-TB drugs with glycerine as a carbon source. In principle, after drug pretreatment for 4-5 days, the response differences between the sensors made of drug-sensitive isolates are distinguishable from the sensors made of drug-resistant isolates. The susceptibility of the M. tuberculosis H37Ra strain, its mutants and 35 clinical isolates to six common anti-TB drugs: rifampicin, isoniazid, streptomycin, ethambutol, levofloxacin and para-aminosalicylic acid were tested using the proposed method. The results agreed well with the gold standard method (LJ) and were determined in significantly less time. The whole procedure takes approximately 11 days and therefore has the potential to inform clinical decisions.. To our knowledge, this is the first study that demonstrates the possible application of a dissolved oxygen electrode-based microbial sensor in M. tuberculosis drug resistance testing. This study used the microbial sensor to perform DST of M. tuberculosis and shorten the time required for DST.. The overall detection result of the microbial sensor agreed well with that of the conventional LJ proportion method and takes less time than the existing phenotypic methods. In future studies, we will build an O

Topics: Antitubercular Agents; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Streptomycin; Tuberculosis; Tuberculosis, Multidrug-Resistant

The emergence of drug-resistant tuberculosis has generated great concern in the control of tuberculosis and HIV/TB patients have established severe complications that are difficult to treat. Although, the gold standard of drug-susceptibility testing is highly accurate and efficient, it is time-consuming. Diagnostic biomarkers are, therefore, necessary in discriminating between infection from drug-resistant and drug-susceptible strains. One strategy that aids to effectively control tuberculosis is understanding the function of secreting proteins that mycobacteria use to manipulate the host cellular defenses. In this study, culture filtrate proteins from Mycobacterium tuberculosis H37Rv, isoniazid-resistant, rifampicin-resistant and multidrug-resistant strains were gathered and profiled by shotgun-proteomics technique. Mass spectrometric analysis of the secreted proteome identified several proteins, of which 837, 892, 838 and 850 were found in M. tuberculosis H37Rv, isoniazid-resistant, rifampicin-resistant and multidrug-resistant strains, respectively. These proteins have been implicated in various cellular processes, including biological adhesion, biological regulation, developmental process, immune system process localization, cellular process, cellular component organization or biogenesis, metabolic process, and response to stimulus. Analysis based on STITCH database predicted the interaction of DNA topoisomerase I, 3-oxoacyl-(acyl-carrier protein) reductase, ESAT-6-like protein, putative prophage phiRv2 integrase, and 3-phosphoshikimate 1-carboxyvinyltransferase with isoniazid, rifampicin, pyrazinamide, ethambutol and streptomycin, suggesting putative roles in controlling the anti-tuberculosis ability. However, several proteins with no interaction with all first-line anti-tuberculosis drugs might be used as markers for mycobacterial identification.

Topics: Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Ethambutol; Gene Expression Profiling; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Proteomics; Pyrazinamide; Rifampin; Streptomycin; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Bacterial Typing Techniques; Cohort Studies; Drug Resistance, Multiple, Bacterial; Extensively Drug-Resistant Tuberculosis; Genome, Bacterial; Genotype; Humans; Kanamycin; Levofloxacin; Microbial Sensitivity Tests; Moxifloxacin; Mycobacterium tuberculosis; Phenotype; Rifampin; Tuberculosis, Multidrug-Resistant; Whole Genome Sequencing

Lopinavir-ritonavir forms the backbone of current first-line antiretroviral regimens in young HIV-infected children. As multidrug-resistant (MDR) tuberculosis (TB) frequently occurs in young children in high-burden TB settings, it is important to identify potential interactions between MDR-TB treatment and lopinavir-ritonavir. We describe the pharmacokinetics of and potential drug-drug interactions between lopinavir-ritonavir and drugs routinely used for MDR-TB treatment in HIV-infected children. A combined population pharmacokinetic model was developed to jointly describe the pharmacokinetics of lopinavir and ritonavir in 32 HIV-infected children (16 with MDR-TB receiving treatment with combinations of high-dose isoniazid, pyrazinamide, ethambutol, ethionamide, terizidone, a fluoroquinolone, and amikacin and 16 without TB) who were established on a lopinavir-ritonavir-containing antiretroviral regimen. One-compartment models with first-order absorption and elimination for both lopinavir and ritonavir were combined into an integrated model. The dynamic inhibitory effect of the ritonavir concentration on lopinavir clearance was described using a maximum inhibition model. Even after adjustment for the effect of body weight with allometric scaling, a large variability in lopinavir and ritonavir exposure, together with strong correlations between the pharmacokinetic parameters of lopinavir and ritonavir, was detected. MDR-TB treatment did not have a significant effect on the bioavailability, clearance, or absorption rate constants of lopinavir or ritonavir. Most children (81% of children with MDR-TB, 88% of controls) achieved therapeutic lopinavir trough concentrations (>1 mg/liter). The coadministration of lopinavir-ritonavir with drugs routinely used for the treatment of MDR-TB was found to have no significant effect on the key pharmacokinetic parameters of lopinavir or ritonavir. These findings should be considered in the context of the large interpatient variability found in the present study and the study's modest sample size.

Topics: Anti-HIV Agents; Antitubercular Agents; Child; Drug Administration Schedule; Drug Combinations; Drug Interactions; Ethambutol; Female; HIV; HIV Infections; Humans; Isoniazid; Lopinavir; Male; Models, Statistical; Mycobacterium tuberculosis; Pyrazinamide; Rifampin; Ritonavir; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Topics: Humans; Mycobacterium tuberculosis; Prospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

The Xpert MTB/RIF assay is an automated molecular test that has improved the detection of tuberculosis and rifampicin resistance, but its sensitivity is inadequate in patients with paucibacillary disease or HIV. Xpert MTB/RIF Ultra (Xpert Ultra) was developed to overcome this limitation. We compared the diagnostic performance of Xpert Ultra with that of Xpert for detection of tuberculosis and rifampicin resistance.. In this prospective, multicentre, diagnostic accuracy study, we recruited adults with pulmonary tuberculosis symptoms presenting at primary health-care centres and hospitals in eight countries (South Africa, Uganda, Kenya, India, China, Georgia, Belarus, and Brazil). Participants were allocated to the case detection group if no drugs had been taken for tuberculosis in the past 6 months or to the multidrug-resistance risk group if drugs for tuberculosis had been taken in the past 6 months, but drug resistance was suspected. Demographic information, medical history, chest imaging results, and HIV test results were recorded at enrolment, and each participant gave at least three sputum specimen on 2 separate days. Xpert and Xpert Ultra diagnostic performance in the same sputum specimen was compared with culture tests and drug susceptibility testing as reference standards. The primary objectives were to estimate and compare the sensitivity of Xpert Ultra test with that of Xpert for detection of smear-negative tuberculosis and rifampicin resistance and to estimate and compare Xpert Ultra and Xpert specificities for detection of rifampicin resistance. Study participants in the case detection group were included in all analyses, whereas participants in the multidrug-resistance risk group were only included in analyses of rifampicin-resistance detection.. Between Feb 18, and Dec 24, 2016, we enrolled 2368 participants for sputum sampling. 248 participants were excluded from the analysis, and 1753 participants were distributed to the case detection group (n=1439) and the multidrug-resistance risk group (n=314). Sensitivities of Xpert Ultra and Xpert were 63% and 46%, respectively, for the 137 participants with smear-negative and culture-positive sputum (difference of 17%, 95% CI 10 to 24); 90% and 77%, respectively, for the 115 HIV-positive participants with culture-positive sputum (13%, 6·4 to 21); and 88% and 83%, respectively, across all 462 participants with culture-positive sputum (5·4%, 3·3 to 8·0). Specificities of Xpert Ultra and Xpert for case detection were 96% and 98% (-2·7%, -3·9 to -1·7) overall, and 93% and 98% for patients with a history of tuberculosis. Xpert Ultra and Xpert performed similarly in detecting rifampicin resistance.. For tuberculosis case detection, sensitivity of Xpert Ultra was superior to that of Xpert in patients with paucibacillary disease and in patients with HIV. However, this increase in sensitivity came at the expense of a decrease in specificity.. Government of Netherlands, Government of Australia, Bill & Melinda Gates Foundation, Government of the UK, and the National Institute of Allergy and Infectious Diseases.

Topics: Adult; Africa; Antibiotics, Antitubercular; Asia; Bacteriological Techniques; Brazil; Drug Resistance, Bacterial; Europe; Female; Humans; Male; Middle Aged; Molecular Diagnostic Techniques; Mycobacterium tuberculosis; Prospective Studies; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Mycobacterium tuberculosis isolates that fail to hybridize to at least one rpoB wild-type or any mutation probe on the Genotype MTBDRplus strip are assumed to be rifampicin-resistant. However, the precise mutation(s) are unknown. We sought to identify the mutations in isolates with such hybridization patterns and determine if the mutations are associated with resistance to rifampicin.. In this study, 275 M. tuberculosis isolates were screened with the Genotype MTBDRplus assay to identify isolates with the hybridization pattern. These isolates were sequenced and their minimum inhibitory concentrations (MIC) determined using the Bactec MGIT 960 system.. Among the 275 isolates tested, 15 (6%) isolates with the hybridization pattern were identified. Sequencing showed that failure to hybridize to rpoB wild-type probes resulted from the presence of 'disputed' rifampicin mutations, which are mutations not always associated with a rifampicin-resistant phenotype. All, except 3/15, isolates had a rifampicin-resistant phenotype (MIC > 1 μg/mL). One of the three isolates with a rifampicin-susceptible phenotype had the same mutation at position 526 (His526Leu) as another isolate that had a rifampicin-resistant phenotype.. The recommendation of the Genotype MTBDRplus assay to assume rifampicin resistance based solely on failure to hybridize to rpoB wild-type probe allows the identification of important RIF-resistant isolates. About 20% (3/15) of such isolates could be missed by relying only on the standard MGIT 960 DST assay for drug susceptibility testing.

Topics: Antitubercular Agents; Bacterial Proteins; Base Sequence; Diagnosis, Differential; Diagnostic Tests, Routine; DNA-Directed RNA Polymerases; DNA, Bacterial; Drug Resistance, Bacterial; Genes, Bacterial; Genotype; Humans; Isoniazid; Microbial Sensitivity Tests; Microbial Viability; Mutation; Mycobacterium tuberculosis; Phenotype; Rifampin; Tuberculosis, Multidrug-Resistant

Correct and rapid determination of Mycobacterium tuberculosis (MTB) resistance against available tuberculosis (TB) drugs is essential for the control and management of TB. Conventional molecular diagnostic test assumes that the presence of any well-studied single nucleotide polymorphisms is sufficient to cause resistance, which yields low sensitivity for resistance classification.. Given the availability of DNA sequencing data from MTB, we developed machine learning models for a cohort of 1839 UK bacterial isolates to classify MTB resistance against eight anti-TB drugs (isoniazid, rifampicin, ethambutol, pyrazinamide, ciprofloxacin, moxifloxacin, ofloxacin, streptomycin) and to classify multi-drug resistance.. Compared to previous rules-based approach, the sensitivities from the best-performing models increased by 2-4% for isoniazid, rifampicin and ethambutol to 97% (P < 0.01), respectively; for ciprofloxacin and multi-drug resistant TB, they increased to 96%. For moxifloxacin and ofloxacin, sensitivities increased by 12 and 15% from 83 and 81% based on existing known resistance alleles to 95% and 96% (P < 0.01), respectively. Particularly, our models improved sensitivities compared to the previous rules-based approach by 15 and 24% to 84 and 87% for pyrazinamide and streptomycin (P < 0.01), respectively. The best-performing models increase the area-under-the-ROC curve by 10% for pyrazinamide and streptomycin (P < 0.01), and 4-8% for other drugs (P < 0.01).. The details of source code are provided at http://www.robots.ox.ac.uk/~davidc/code.php.. david.clifton@eng.ox.ac.uk.. Supplementary data are available at Bioinformatics online.

Topics: Antitubercular Agents; Ciprofloxacin; Ethambutol; Humans; Isoniazid; Machine Learning; Microbial Sensitivity Tests; Moxifloxacin; Mycobacterium tuberculosis; Ofloxacin; Pyrazinamide; Rifampin; Sequence Analysis, DNA; Streptomycin; Tuberculosis, Multidrug-Resistant

To evaluate the performance of nitrate reductase assay on smear positive pulmonary specimens for detection of multi and extensively drug resistant tuberculosis simultaneously.. Cross-sectional analytical study.. Microbiology Department, Armed Forces Institute of Pathology, Rawalpindi from June to December 2016.. Smear positive pulmonary samples were processed both by nitrate reductase method on Lowenstein Jenson medium and also inoculated on gold standard Bactec MGIT 960 TB system. All the specimens were first digested and decontaminated according to standard protocol before inoculation.. Out of total 76 samples, three did not give color and, therefore, were excluded from the final data analysis. Among the remaining 73 samples, mycobacterial index was: 28 specimens were having 1+ (1-9 bacilli/100 fields), 26 samples were 2+ (1-9 bacilli/ field), and 19 samples were having 3+ index (>9 bacilli/field). The respective sensitivity and specificity were 84% and 100% for isoniazid (INH); 82% and 100% for rifampin (RIF); 67% and 100% for amikacin (AK); and both 100% for ofloxacin (OFX). Overall agreement in case of INH, RIF, AK, and OFX was 94.5%, 97.2%, 98.6% and100%, respectively. Overall average agreement was 97.5%.. Nitrate reductase assay is a reliable, low cost and accurate method that can be used for early for diagnosis of multi and extensively drug resistant tuberculosis.

Topics: Amikacin; Antitubercular Agents; Cross-Sectional Studies; Drug Resistance, Multiple, Bacterial; Early Diagnosis; Extensively Drug-Resistant Tuberculosis; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Nitrate Reductase; Predictive Value of Tests; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant

The treatment of drug-susceptible tuberculosis (TB) is long and cumbersome. Mismanagement of TB treatment can lead to the emergence of drug resistance in patients, so shortening the treatment duration could significantly improve TB chemotherapy and prevent the development of drug resistance. We previously discovered that high concentrations of vitamin C sterilize cultures of drug-susceptible and drug-resistant

Topics: Animals; Antitubercular Agents; Ascorbic Acid; Disease Models, Animal; Drug Resistance, Bacterial; Drug Synergism; Drug Therapy, Combination; Female; Humans; Injections, Intraperitoneal; Isoniazid; Lung; Mice; Mice, Inbred CBA; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant

Heteroresistant Mycobacterium tuberculosis (mixture of susceptible and resistant subpopulations) is thought to be a preliminary stage to full resistance and timely detection, initiation of correct treatment is vital for successful anti tubercular therapy. The aim of this study was to detect multi drug resistant (MDR) and heteroresistant M. tuberculosis with the associated gene mutations from patients of tuberculous meningitis.. A total of 197 M. tuberculosis isolates from 478 patients of TBM were isolated from July 2012 to July 2015 and subjected to drug susceptibility testing (DST) by BACTEC MGIT and Genotype MTBDR line probe assay (LPA). Heteroresistance was defined as presence of both WT and mutant genes in LPA.. Of 197 M. tuberculosis isolates, 11 (5.6%) were MDR, 23 (11.6%), 1 (0.5%) were mono resistant to isoniazid (INH) and rifampicin (RMP) respectively. Heteroresistance was detected in 8 (4%), 2 (1%) isolates to INH and RMP respectively. INH heteroresistant strains had WT bands with mutation band S315T1 whereas RMP heteroresistant strains had WT bands with mutation band S531L.. The prevalence of MDR M. tuberculosis was 5.6% in TBM patients with the most common mutation being ΔWT band with S315T1 for INH and ΔWT band with S531T for RMP. MGIT DST was found to be more sensitive for detecting overall resistance in M. tuberculosis but inclusion of LPA not only reduced time for early initiation of appropriate treatment but also enabled detection of heteroresistance in 8 (4%), 2 (1%) isolates for INH and RMP respectively.

Topics: Antitubercular Agents; Female; Humans; Incidence; India; Isoniazid; Male; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Prospective Studies; Rifampin; Tuberculosis, Meningeal; Tuberculosis, Multidrug-Resistant

In this work, we conducted bacterial population profile studies to assess trends of rifampin (RIF) resistance of

Topics: Bacterial Proteins; China; Codon; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

There is limited data that investigates the national rates of drug-resistant tuberculosis (TB) in Saudi Arabia.This study aimed to estimate the rates of multi-drug-resistant tuberculosis (MDR-TB), rifampicin-resistant tuberculosis (RR-TB), and monoresistance (MR) in Saudi Arabia.. A retrospective cohort study was conducted on all TB cases reported to the National TB Control and Prevention Program (NTCPP) registry at the Saudi Ministry of Health between January 1, 2014 and December 31, 2015. A total of 2098 TB patients with positive TB cultures were included in the study. Subgroup analyses and multivariate binary logistic regression models were performed with IBM SPSS 23.0.. Of the total TB cases, 4.4% (95% CI: 3.59%-5.40%) were found to have MDR-TB. The rates of MR were 3.8% (95% CI: 2.99%-4.67%) for ethambutol, 5.4% (95% CI: 4.50%-6.49%) for pyrazinamide, 10.2% (95% CI: 5.89%-11.52%) for isoniazid, 11% (95% CI: 9.70%-12.43%) for streptomycin, and 5.9% (95% CI: 4.90%-6.96%) for rifampicin. The high rates of MDR and RR-TB were found among the younger age group, female gender, and those who had a previous history of TB. We also discovered that renal failure tends to increase the risk of rifampicin resistance.. National TB data in Saudi Arabia shows that the rate of MDR-TB was similar to the global rate reported by the World Health Organization (WHO). It is a relatively high rate as compared to Western countries. The proportion of MDR/RR-TB patients tends to be higher in the younger age group, female gender, and in patients with a previous history of TB treatment. Effective strategies for prevention of all multi-drug-resistant TB cases are warranted.

Topics: Adult; Age Factors; Antitubercular Agents; Ethambutol; Female; Humans; Isoniazid; Logistic Models; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Pyrazinamide; Regression Analysis; Retrospective Studies; Rifampin; Saudi Arabia; Sex Factors; Streptomycin; Tuberculosis, Multidrug-Resistant; World Health Organization; Young Adult

The gap between patients diagnosed with multi-drug resistant tuberculosis (MDR-TB) and enrolment in treatment is one of the major challenges in tuberculosis control programmes. A 4-year (2013-2016) retrospective review of patients' clinical data and subsequent in-depth interviews with health providers were conducted to assess the effectiveness of the GeneXpert GxAlert platform for MDR-TB diagnosis and its impact on linkage of patients to care in Tanzania.. A total of 782 new rifampicin resistant cases were notified, but only 242 (32.3%) were placed in an MDR-TB regimens. The remaining 540 (67.07%) patients were not on treatment, of which 103 patients had complete records on the GxAlert database. Of the 103 patients: 39 were judged as untraceable; 27 died before treatment; 12 were treated with first-line anti-TBs; 9 repeat tests did not show rifampicin resistance; 15 were not on treatment due to communication breakdown, and 1 patient was transferred outside the country. In-depth interviews with health providers suggested that the pre-treatment loss for the MDR-TB patients was primarily attributed to health system and patients themselves. We recommend strengthening the health system by developing and implementing well-defined interventions to ensure all diagnosed MDR-TB patients are accurately reported and timely linked to treatment.

Topics: Adult; Antibiotics, Antitubercular; Drug Resistance, Multiple, Bacterial; Humans; Patient Acceptance of Health Care; Patient Navigation; Rifampin; Tanzania; Tuberculosis, Multidrug-Resistant

In high tuberculosis (TB)-burden countries such as China, the diagnosis of multidrug-resistant tuberculosis (MDR-TB) using conventional drug susceptibility testing (DST) takes months, making treatment delay inevitable. Poor outcomes of MDR-TB might be associated with delayed, even inappropriate, treatment. The purposes of this study were to investigate the time to MDR-TB treatment initiation and to assess the association between early treatment and treatment outcomes. Between April 2011 and December 2014, this population-based retrospective cohort study collected the demographic and clinical characteristics and the drug susceptibility profiles of all registered MDR-TB patients in Shanghai, China. The dates of TB and MDR-TB diagnoses, DST performance, and treatment initiation were extracted to calculate the times to treatment. In total, 284 of 346 MDR-TB patients were eligible for analysis, and 68.3% (194/284) had favored outcomes. The median time to treatment initiation from TB diagnosis was 172 days among those with favored outcomes and 190 days among those with poor outcomes. Treatments initiated within 60 days after performing DST (odds ratio [OR], 2.56; 95% confidence interval [CI], 1.22 to 5.36) and empirical treatments (OR, 2.09; 95% CI, 1.01 to 4.32) were positively associated with favored outcomes. Substantial delays to MDR-TB treatment were observed when conventional DST was used. Early treatment predicted favored outcomes. Rapid diagnostic methods should be scaled up and improvements should be made in patient management and information linkage to reduce treatment delay.

Topics: Adult; Antitubercular Agents; China; Female; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Humans; Rifampin; Tuberculosis, Multidrug-Resistant

Tuberculosis (TB) is caused by M. tuberculosis complex and remains a major global public health problem. The epidemic remains a threat to sub-Saharan Africa, including Ethiopia, with further emergence of drug resistant TB. We investigated the drug sensitivity pattern and molecular epidemiology of mycobacterial strains isolated from pulmonary TB patients in and around Ambo town in Oromia Region, Central Ethiopia.. A cross-sectional study was conducted involving 105 consecutive new smear positive pulmonary TB patients diagnosed at Ambo Hospital and surrounding Health Centers between May 2014 and March 2015 upon informed consent. Sputum samples were cultured on Löwenstein-Jensen (LJ) media using standard techniques to isolate mycobacteria. Region of difference 9 (RD9)-based polymerase chain reaction (PCR) and spoligotyping was employed for the identification of the isolates at species and strain levels. The spoligotype patterns were entered into the SITVIT database to determine Octal and SIT (Spoligotyping International Typing) numbers for each strain. The sensitivity of the isolates to isoniazid (INH), rifampicin (RIF), ethambutol (ETB) and streptomycin (STM) was evaluated on LJ-medium with the indirect proportion method.. Cultures were positive in 86/105 (82%) of newly diagnosed smear positive pulmonary TB cases. All of the 86 isolates were confirmed as M. tuberculosis. The majority (76.7%) of them were clustered into seven groups while the rest (23.3%) appeared unique. The most predominant Spoligotypes were SIT53 and SIT149, consisting of 24.4% and 20.9% of the isolates, respectively. Assigning of the isolates to family using SPOTCLUST software revealed that 45.3% of the isolates belonged to T1, 23.3% to T3 and 13% to CAS family. The majority (76.7%) of the M. tuberculosis isolates were susceptible to all the four drugs. Any resistance to any one of the four drugs was detected in 23.3% of the isolates. The highest proportion of any resistance was observed against isoniazid (9.3%) and ethambutol (7%). There was only a single case (1.2%) of multidrug resistant/rifampicin resistant (MDR/RR) TB.. The majority of the isolates were clustered suggesting on-going active transmission in the study area. Mono resistance is relatively prevalent while the magnitude of MDR/RR-TB was found to be lower than in previous studies.

Topics: Adolescent; Adult; Cross-Sectional Studies; Ethambutol; Ethiopia; Female; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Molecular Epidemiology; Mycobacterium tuberculosis; Rifampin; RNA, Viral; Streptomycin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

Drug resistant tuberculosis (TB) is increasing in prevalence worldwide. Treatment failure and relapse is known to be high for patients with isoniazid resistant TB treated with standard first line regimens. However, risk factors for unfavourable outcomes and the optimal treatment regimen for isoniazid resistant TB are unknown. This cohort study was conducted when Vietnam used the eight month first line treatment regimen and examined risk factors for failure/relapse among patients with isoniazid resistant TB.. Between December 2008 and June 2011 2090 consecutive HIV-negative adults (≥18 years of age) with new smear positive pulmonary TB presenting at participating district TB units in Ho Chi Minh City were recruited. Participants with isoniazid resistant TB identified by Microscopic Observation Drug Susceptibility (MODS) had extended follow-up for 2 years with mycobacterial culture to test for relapse. MGIT drug susceptibility testing confirmed 239 participants with isoniazid resistant, rifampicin susceptible TB. Bacterial and demographic factors were analysed for association with treatment failure and relapse.. Using only routine programmatic sputum smear microscopy for assessment, (months 2, 5 and 8) 30/239 (12.6%) had an unfavourable outcome by WHO criteria. Thirty-nine patients were additionally detected with unfavourable outcomes during 2 year follow up, giving a total of 69/239 (28.9%) of isoniazid (INH) resistant cases with unfavourable outcome by 2 years of follow-up. Beijing lineage was the only factor significantly associated with unfavourable outcome among INH-resistant TB cases during 2 years of follow-up. (adjusted OR = 3.16 [1.54-6.47], P = 0.002).. One third of isoniazid resistant TB cases suffered failure/relapse within 2 years under the old eight month regimen. Over half of these cases were not identified by standard WHO recommended treatment monitoring. Intensified research on early identification and optimal regimens for isoniazid resistant TB is needed. Infection with Beijing genotype of TB is a significant risk factor for bacterial persistence on treatment resulting in failure/relapse within 2 years. The underlying mechanism of increased tolerance for standard drug regimens in Beijing genotype strains remains unknown.

Topics: Adolescent; Adult; Antitubercular Agents; Cohort Studies; Female; Humans; Isoniazid; Male; Middle Aged; Mycobacterium tuberculosis; Recurrence; Rifampin; Risk Factors; Sputum; Treatment Failure; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Vietnam; Young Adult

Regional tuberculosis (TB) centres of the Yangon and Mandalay Regions of Myanmar, which account for 65% of all notified rifampicin-resistant tuberculosis (RR-TB) cases countrywide.. To determine 1) initial loss to follow-up (LTFU), 2) treatment delay, and 3) factors associated with initial LTFU and treatment delay among RR-TB patients residing in the Yangon and Mandalay regions diagnosed using Xpert® during January-August 2016.. This was a retrospective cohort study. Each diagnosed patient was tracked in the drug-resistant TB treatment registers of the Yangon and Mandalay regional treatment centres for January-December 2016 using patient name, age, sex, township and date of diagnosis. If the diagnosed patient was not found in the treatment register by 31 December 2016, he/she was considered 'initial LTFU'.. Of the 1037 RR-TB patients diagnosed, 310 (30%) experienced initial LTFU, which was significantly higher among patients aged 55 years and among those diagnosed in the Mandalay Region. A treatment delay of >1 month was observed in 440 (70%) patients (median delay 41 days). Delay was uniformly high across patient subgroups, and was not associated with any factor.. Initial LTFU and treatment delays among RR-TB patients were high. Future studies using qualitative research methods are needed to ascertain the reasons for this observation.

Topics: Adolescent; Adult; Child; Child, Preschool; Female; HIV Infections; Humans; Infant; Infant, Newborn; Lost to Follow-Up; Male; Middle Aged; Multivariate Analysis; Myanmar; Mycobacterium tuberculosis; Regression Analysis; Retrospective Studies; Rifampin; Time-to-Treatment; Tuberculosis, Multidrug-Resistant; Young Adult

To estimate the provider costs of managing adverse drug reactions (ADRs) to standard long-course treatment for multidrug- and rifampicin-resistant tuberculosis (MDR/RR-TB) according to South African guidelines.. We parameterised a published Markov health state model for MDR/RR-TB with guidelines-based, bottom-up public-sector provider costing of ADR management. Frequency of ADR occurrence was extracted from the literature. Costs were estimated over 10 years, discounted 3% annually and tested using probabilistic sensitivity analysis.. On average, guidelines-based costing of moderate ADRs weighted by the frequency of occurrence was US$135.76 (standard deviation [SD] US$17.18) and the cost of serious ADRs was US$521.29 (SD US$55.99). We estimated that the incremental costs of ADR management were US$380.17 annually per patient initiating MDR/RR-TB treatment. The incremental costs of ADR management for the public health sector in South Africa was US$4.76 million, 8.3% of the estimated cohort costs of MDR/RR-TB treatment ($57.55 million) for the 2015 cohort of 12 527 patients.. Management of multiple ADRs and serious ADRs, which are common during the first 6 months of standard, long-course MDR/RR-TB treatment, substantially increases provider treatment costs. These results need to be taken into account when comparing regimen costs, and highlight the urgent need to identify drug regimens with improved safety profiles.

Topics: Antitubercular Agents; Cost-Benefit Analysis; Drug-Related Side Effects and Adverse Reactions; Health Care Costs; Humans; Markov Chains; Rifampin; South Africa; Tuberculosis, Multidrug-Resistant

The aim of this study was to identify mutations of rpoB, katG, inhA and ahp-genes associated Mycobacterium tuberculosis resistance to rifampicin (RIF) and isoniazid (INH) in Kyrgyz Republic. We studied 633 smear samples from the primary pulmonary tuberculosis (TB) patients. We verified Mycobacterium tuberculosis susceptibility to RIF and INH using culture method of absolute concentrations, and commercially available test named "TB-BIOCHIP" (Biochip-IMB, Moscow, Russian Federation).. For RIF-resistance, TB-BIOCHIP's sensitivity and specificity were 88% and 97%, 84% and 95% for INH-resistance, and 90% and 97% for multi-drug resistance (MDR). In RIF-resistant strains, TB-BIOCHIP showed mutations in codons 531 (64.8%), 526 (17.3%), 516 (8.1%), 511 (5.4%), 533 (3.2%), 522 (0.6%) and 513 (0.6%) of rpoB gene. The most prevalent was Ser531 > Leu mutation (63.7%). 91.2% of mutations entailing resistance to INH were in katG gene, 7% in inhA gene, and 1.8% in ahpC gene. Ser315→Thr (88.6%) was the most prevalent mutation leading to resistance to INH.. In Kyrgyz Republic, the most prevalent mutation in RIF-resistant strains was Ser531 → Leu in rpoB gene, as opposed to Ser315 → Thr in katG gene in INH-resistant Mycobacterium tuberculosis. In Kyrgyz Republic, the major reservoir of MDR Mycobacterium tuberculosis were strains with combined mutations Ser531 → Leu in rpoB gene and Ser315 → Thr in katG gene. TB-BIOCHIP has shown moderate sensitivity with the advantage of obtaining results in only two days.

Topics: Adolescent; Adult; Aged; Antitubercular Agents; Bacterial Proteins; Catalase; DNA-Directed RNA Polymerases; DNA, Bacterial; Drug Resistance, Multiple, Bacterial; Female; Humans; Isoniazid; Kyrgyzstan; Male; Microbial Sensitivity Tests; Middle Aged; Molecular Epidemiology; Mutation; Mutation Rate; Mycobacterium tuberculosis; Oxidoreductases; Peroxidases; Phenotype; Rifampin; Tuberculosis, Multidrug-Resistant; Young Adult

Topics: Antitubercular Agents; Communicable Disease Control; Databases, Factual; Diarylquinolines; Humans; Infectious Disease Medicine; Isoniazid; Mycobacterium tuberculosis; Nitroimidazoles; Oxazoles; Patient Safety; Public Health; Rifampin; Tuberculosis, Multidrug-Resistant; World Health Organization

For

Topics: Antitubercular Agents; Bacterial Proteins; DNA, Bacterial; Drug Resistance, Multiple, Bacterial; Genotype; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Sequence Analysis, DNA; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Drug Therapy, Combination; Humans; Isoniazid; Mycobacterium tuberculosis; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Multidrug-resistant tuberculosis (MDR-TB) is resistant to the two main first-line anti-tuberculosis drugs: rifampicin and isoniazid. It is a major threat to public health worldwide. The objective of this study was to assess the potential risk factors for multidrug-resistant tuberculosis among patients undergoing MDR-TB treatment at two community hospitals in Ethiopia.. A case-control study design was conducted from February 1, 2016, to April 29, 2016. TB-positive patients with MDR-TB and non-MDR-TB were considered as cases and controls, respectively. A total of 219 study participants were included in the study. An interviewer-administered structured questionnaire was used to collect primary data from the patients, and a checklist was used to collect data from the clinical records. Bivariate and multivariate logistic regression analyses were used to assess the potential risk factors for the occurrence of MDR-TB.. The odds of developing MDR-TB were higher in patients previously treated with anti-TB drugs (odds ratio [OR] = 6.1, 95%CI: 2.92-12.62, P < 0.001), those with a history of contact with known TB patients (OR = 2.1, 95%CI: 1.04-4.43, P < 0.001), those living in a rural setting (OR = 5.6, 95%CI: 2.14-14.46, P = 0.001), those with a history of alcohol consumption (OR = 4.3, 95%CI: 2.29-10.49, P < 0.001) and those without a job (OR = 2.4, 95%CI: 1.06-5.42, P = 0.001).. The study revealed that contact with known TB patients, previous TB treatment, residence area, lack of a job, and alcohol consumption were potential risk factors for the occurrence of MDR-TB. Enhancing public health education, intensifying directly observed therapy programmes for all TB patients and designing control strategies are recommended.

Topics: Adult; Aged; Aged, 80 and over; Antitubercular Agents; Case-Control Studies; Ethiopia; Female; Hospitals, Community; Humans; Isoniazid; Male; Middle Aged; Rifampin; Risk Factors; Surveys and Questionnaires; Tuberculosis, Multidrug-Resistant; Young Adult

Tuberculosis continues to be a major health problem worldwide. Multidrug resistant tuberculosis (MDR-TB) infection that occurs in childhood is caused by adult MDR-TB agents which are in circulation and resistant to primary drugs. In this case report a 17-month-old child with MDR-TB who was cured after a 24-month therapy regimen was presented. Physical examination of a 17-month-old girl admitted to the hospital with the cause of recurrent pneumonia revealed a rubbery lymphadenopathy less than 2 cm in the right upper cervical region. Crepitant rales were detected in the right basal on auscultation of the lung. Interferon gamma release assay (IGRA) and tuberculin skin (TST) tests were negative. Computed tomography (CT) scan of the chest showed mediastinal conglomerate pathologic lymphadenopathy and air bronchograms were detected near the lower lobe of the left lung. Treatment of isoniazid, rifampicin, pyrazinamide with the diagnosis of epituberculosis was started by taking a sample of gastric aspirate culture sample. In the sixth month of the treatment patient was admitted to our clinic with enlarged cervical rubbery lymphadenopathy. It was determined that microbiological test of gastric aspirate culture specimen was positive for M.tuberculosis complex resistant to isoniazid, rifampin, ethambutol, streptomycin, ethionamide and rifabutin. Control CT showed residual peribronchial infiltrations and hilar calcific lymph nodes. Hearing test, vision control and, thyroid function tests were performed and treatment of moxifloxacin, amikacin, para-amino salicylic acid, protionamide and pyrazinamide was started based on minor drug susceptibility results of M.tuberculosis isolate which was still growing in gastric aspirate culture. Gastric aspirate culture for M.tuberculosis was still positive after 3 months of treatment and the current treatment was continued. Amikacin was stopped after 6 months. Therapy regimen was stopped after 24-months. Over the course of a follow-up period of more than 3 years, the clinical and radiological resultsof the patient has improved significantly. The clinical presentation of TB in children is often nonspecific and differs from the patterns seen in adults. MDR-TB cases can be seen in this age group since tuberculosis in children is mainly caused by transmission of drug-resistant strains from adults. This situation is particularly problematic due to the long-term treatment and the lack of specific drug formulations for children.

Topics: Adult; Antitubercular Agents; Female; Humans; Infant; Isoniazid; Mycobacterium tuberculosis; Pyrazinamide; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Tuberculosis (TB) remains one of the most deadly infections with approximately a quarter of cases not being identified and/or treated mainly due to a lack of resources. Rapid detection of TB or drug-resistant TB enables timely adequate treatment and is a cornerstone of effective TB management. We evaluated the analytical performance of a single-tube assay for multidrug-resistant TB (MDR-TB) on an experimental platform utilising RT-PCR and melting curve analysis that could potentially be operated as a point-of-care (PoC) test in resource-constrained settings with a high burden of TB. Firstly, we developed and evaluated the prototype MDR-TB assay using specimens extracted from well-characterised TB isolates with a variety of distinct rifampicin and isoniazid resistance conferring mutations and nontuberculous Mycobacteria (NTM) strains. Secondly, we validated the experimental platform using 98 clinical sputum samples from pulmonary TB patients collected in high MDR-TB settings. The sensitivity of the platform for TB detection in clinical specimens was 75% for smear-negative and 92.6% for smear-positive sputum samples. The sensitivity of detection for rifampicin and isoniazid resistance was 88.9 and 96.0% and specificity was 87.5 and 100%, respectively. Observed limitations in sensitivity and specificity could be resolved by adjusting the sample preparation methodology and melting curve recognition algorithm. Overall technology could be considered a promising PoC methodology especially in resource-constrained settings based on its combined accuracy, convenience, simplicity, speed, and cost characteristics.

Topics: Antitubercular Agents; Base Sequence; Drug Resistance, Multiple, Bacterial; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Nucleic Acid Denaturation; Point-of-Care Systems; Rifampin; Sensitivity and Specificity; Sequence Analysis, DNA; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

In 2015, 10.4 million people developed tuberculosis (TB) and 580,000 amongst them suffered from multidrug-resistant TB (MDR-TB). From those 580,000 cases of MDR-TB, only 125,000 were detected and reported. A total of 111,000 people began to receive MDR-TB treatment in 2014 while 190,000 MDR-TB patients were estimated to have died, largely due to lack of access to effective treatment. The mechanism of drug resistance can be caused by genetic factors, factors related to previous treatment and other factors such as comorbidity with diabetes mellitus. Although there is some evidence which postulate host genetic predisposition is the basis for the development of MDR-TB, changes in the genomic content is the major underlying event in the emergence of variants strains in the M. tuberculosis complex. Spontaneous chromosomally-borne mutation occurring in M. tuberculosis at predictable rates are thought to confer resistance to anti-TB drugs. Factors related to previous anti-tuberculosis treatments consists of incomplete or inadequate treatment and also poor treatment adherence. A review of the published literature strongly suggest that the most powerful predictor for the presence of MDR-TB is a history of TB treatment. Many new cases of MDR-TB are created by physician's errors related to drugs regimen, dosing interval and duration of treatment. Multidrug-resistance TB developed due to error in TB management in the past such as initiation of an inadequat regimen using first line anti-TB drugs, the addition of single drug to a failing regimen, the failure to identify pre-existing resistance and variations in bioavailability of anti-TB drugs that predispose the patient to the development of MDR-TB. Non-adherence to prescribed treatment is often underestimated by physicians and difficult to predict. Certain factors such as psychiatric illness, alcoholism, drug additiction and homelessness can predict non-adherence to treatment. Poor compliance with the treatment is also an important factor in the development of acquired drug resistance.Diabetes mellitus has been a well-known risk factor for TB in the past. The global convergence of the accelerating type 2 DM pandemic, high TB prevalence and drug-resistant TB during the past couple of decades has become a serious challenge to clinicians worldwide. Over the past few years, some studies have shown that the treatment failure rate is higher in TB patients with DM as comorbidity. Moreover, there is significant association be

Topics: Antibiotics, Antitubercular; Diabetes Mellitus, Type 2; Humans; Medication Adherence; Mycobacterium tuberculosis; Rifampin; Risk Assessment; Risk Factors; Tuberculosis, Multidrug-Resistant

Bacterial susceptibility is categorized as susceptible, intermediate-susceptible dose-dependent (ISDD), and resistant. The strategy is to use higher doses of first-line agents in the ISDD category, thereby preserving the use of these drugs. This system has not been applied to antituberculosis drugs. Pharmacokinetic/pharmacodynamic (PK/PD) target exposures, in tandem with Monte Carlo experiments, recently identified susceptibility breakpoints of 0.0312 mg/L for isoniazid, 0.0625 mg/L for rifampin, and 50 mg/L for pyrazinamide. These have been confirmed in clinical studies.. Target attainment studies were carried out using Monte Carlo experiments to investigate whether rifampin, isoniazid, and pyrazinamide dose increases would achieve the PK/PD target in >90% of 10000 patients with tuberculosis caused by bacteria, revealing minimum inhibitory concentrations (MICs) between the proposed and the traditional breakpoints.. We found that an isoniazid dose of 900 mg/day identified a new ISDD MIC range of 0.0312-0.25 mg/L and resistance at MIC ≥0.5 mg/L. Rifampin 1800 mg/day would result in an ISDD of 0.0625-0.25 mg/L and resistance at MIC ≥0.5 mg/L. At a dose of pyrazinamide 4 g/day, the ISDD MIC range was 37.5-50 mg/L and resistance at MIC ≥100 mg/L. Based on MIC distributions, 93% (isoniazid), 78% (rifampin), and 27% (pyrazinamide) of isolates would be within the ISDD range.. Drug susceptibility testing at 2 concentrations delineating the ISDD range, and subsequently using higher doses, could prevent switching to a more toxic second-line treatment. Confirmatory clinical studies would provide evidence to change treatment guidelines.

Topics: Algorithms; Antitubercular Agents; Humans; Isoniazid; Microbial Sensitivity Tests; Monte Carlo Method; Mycobacterium tuberculosis; Pyrazinamide; Rifampin; South Africa; Tuberculosis, Multidrug-Resistant

Experience with delamanid (Dlm) is limited, particularly among HIV-positive individuals. We describe early efficacy and safety data from a programmatic setting in South Africa.This was a retrospective cohort study of patients receiving Dlm-containing treatment regimens between November 2015 and August 2017. We report 12-month interim outcomes, sputum culture conversion (SCC) by months 2 and 6, serious adverse events (SAEs) and QT intervals corrected using the Frederica formula (QTcF).Overall, 103 patients were initiated on Dlm; 79 (77%) were HIV positive. The main indication for Dlm was intolerance to second-line anti-tuberculosis (TB) drugs (n=58, 56%). There were 12 months of follow-up for 46 patients; 28 (61%) had a favourable outcome (cure, treatment completion or culture negativity). Positive cultures were found for 57 patients at Dlm initiation; 16 out of 31 (52%) had SCC within 2 months and 25 out of 31 (81%) within 6 months. There were 67 SAEs reported in 29 patients (28%). There were four instances of QTcF prolongation >500 ms in two patients (2%), leading to permanent discontinuation in one case; however, no cardiac arrhythmias occurred.This large cohort of difficult-to-treat patients receiving Dlm for rifampicin-resistant TB treatment in a programmatic setting with high HIV prevalence had favourable early treatment response and tolerated treatment well. Dlm should remain available, particularly for those who cannot be treated with conventional regimens or with limited treatment options.

Topics: Adult; Antitubercular Agents; Female; Humans; Logistic Models; Male; Nitroimidazoles; Oxazoles; Retrospective Studies; Rifampin; South Africa; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Topics: Antitubercular Agents; Emigrants and Immigrants; Extensively Drug-Resistant Tuberculosis; Humans; Italy; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

To evaluate prevalence and patterns of drug resistance among pulmonary tuberculosis (TB) patients in Hangzhou City, China.. Sputum samples of smear positive TB patients enrolled in 2011 and 2015 were collected and tested for drug susceptibility, and demographic and medical record data were extracted from the electronic database of China Information System for Disease Control and Prevention. Chi-square test was used to compare drug resistance prevalence between new and treated patients and between male and female patients, and Chi-square test for trend was used to compare the prevalence over calendar years 2011 and 2015.. Of 1326 patients enrolled in 2015, 22.3% had resistance to any first-line anti-TB drugs and 8.0% had multi-drug resistance (MDR); drug resistance rates among previously treated cases were significantly higher than among new cases. Significant declines of resistance to isoniazid, rifampin, ethambutol and streptomycin, and MDR from 2011 to 2015 were observed among previously treated patients, while a significant decline of resistance to rifampin was observed among new cases.. While the prevalence of acquired drug resistance decreased due to due to implementation of DOTS-Plus program, the prevalence of primary drug resistance due to transmission remained high. Greater efforts should be made to screen drug resistance for case finding and to reduce transmission through improving the treatment and management of drug-resistant patients.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antitubercular Agents; Child; China; Drug Resistance, Multiple, Bacterial; Ethambutol; Female; Humans; Isoniazid; Male; Middle Aged; Mycobacterium tuberculosis; Rifampin; Streptomycin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

Drug resistant tuberculosis is increasing world-wide. Resistance against isoniazid (INH), rifampicin (RIF), or both (multi-drug resistant TB, MDR-TB) is of particular concern, since INH and RIF form part of the standard regimen for TB disease. While it is known that suboptimal treatment can lead to resistance, it remains unclear how host immune responses and antibiotic dynamics within granulomas (sites of infection) affect emergence and selection of drug-resistant bacteria. We take a systems pharmacology approach to explore resistance dynamics within granulomas. We integrate spatio-temporal host immunity, INH and RIF dynamics, and bacterial dynamics (including fitness costs and compensatory mutations) in a computational framework. We simulate resistance emergence in the absence of treatment, as well as resistance selection during INH and/or RIF treatment. There are four main findings. First, in the absence of treatment, the percentage of granulomas containing resistant bacteria mirrors the non-monotonic bacterial dynamics within granulomas. Second, drug-resistant bacteria are less frequently found in non-replicating states in caseum, compared to drug-sensitive bacteria. Third, due to a steeper dose response curve and faster plasma clearance of INH compared to RIF, INH-resistant bacteria have a stronger influence on treatment outcomes than RIF-resistant bacteria. Finally, under combination therapy with INH and RIF, few MDR bacteria are able to significantly affect treatment outcomes. Overall, our approach allows drug-specific prediction of drug resistance emergence and selection in the complex granuloma context. Since our predictions are based on pre-clinical data, our approach can be implemented relatively early in the treatment development process, thereby enabling pro-active rather than reactive responses to emerging drug resistance for new drugs. Furthermore, this quantitative and drug-specific approach can help identify drug-specific properties that influence resistance and use this information to design treatment regimens that minimize resistance selection and expand the useful life-span of new antibiotics.

Topics: Antitubercular Agents; Computer Simulation; Drug Resistance, Bacterial; Drug Resistance, Multiple; Granuloma; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

The fast and accurate diagnosis of drug-resistant tuberculosis (DR-TB) is critical to reducing the spread of disease. Although commercial genotypic drug-susceptibility tests (DST) are close to the goal, they are still not able to detect all relevant DR-TB related mutations. Whole genome sequencing (WGS) allows better comprehension of DR-TB with a great discriminatory power. We aimed to evaluate WGS in M. tuberculosis isolates compared with phenotypic and genotypic DST.. This cross-sectional study evaluated 30 isolates from patients with detected DR-TB in Brazil and Mozambique. They were evaluated with phenotypic (MGIT-SIRE™) and genotypic (Xpert-MTB/RIF™, Genotype-MTBDRplus™, and MTBDRsl™) DST. Isolates with resistance to at least one first- or second-line drug were submitted to WGS and analyzed with TB profiler database.. WGS had the best performance among the genotypic DST, compared to the phenotypic test. There was a very good concordance with phenotypic DST for rifampicin and streptomycin (89.6%), isoniazid (96.5%) and ethambutol (82.7%). WGS sensitivity and specificity for detection resistance were respectively 87.5 and 92.3% for rifampicin; 95.6 and 100% for isoniazid; 85.7 and 93.3% for streptomycin while 100 and 77.2% for ethambutol. Two isolates from Mozambique showed a Val170Phe rpoB mutation which was neither detected by Xpert-MTB/RIF nor Genotype-MTBDRplus.. WGS was able to provide all the relevant information about M. tuberculosis drug susceptibility in a single test and also detected a mutation in rpoB which is not covered by commercial genotypic DST.

Topics: Antitubercular Agents; Cross-Sectional Studies; DNA, Bacterial; Drug Resistance, Bacterial; Drug Resistance, Multiple, Bacterial; Ethambutol; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Phenotype; Rifampin; Streptomycin; Tuberculosis, Multidrug-Resistant; Whole Genome Sequencing

Multidrug-resistant (MDR) tuberculosis, defined as tuberculosis resistant to the two first-line drugs isoniazid and rifampin, poses a serious problem for global tuberculosis control strategies. Lack of a safe and convenient model organism hampers progress in combating the spread of MDR strains of

Topics: Animals; Antitubercular Agents; Arginine; Bacterial Proteins; Containment of Biohazards; Drug Resistance, Multiple, Bacterial; Female; Humans; Isoniazid; Mice; Mice, Inbred C57BL; Mice, SCID; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Nutrients; Rifampin; Tuberculosis, Multidrug-Resistant

Multidrug drug-resistant tuberculosis (MDR-TB) is a major health problem and seriously threatens TB control and prevention efforts globally. Ethiopia is among the 30th highest TB burden countries for MDR-TB with 14% prevalence among previously treated cases. The focus of this study was on determining drug resistance patterns of Mycobacterium tuberculosis among MDR-TB suspected cases and associated risk factors.. A cross-sectional study was conducted in Addis Ababa from June 2015 to December 2016. Sputum samples and socio-demographic data were collected from 358 MDR-TB suspected cases. Samples were analyzed using Ziehl-Neelsen technique, GeneXpert MTB/RIF assay, and culture using Lowenstein-Jensen and Mycobacterial growth indicator tube. Data were analyzed using SPSS version 23.. A total of 226 the study participants were culture positive for Mycobacterium tuberculosis, among them, 133 (58.8%) participants were males. Moreover, 162 (71.7%) had been previously treated for tuberculosis, while 128 (56.6%) were TB/HIV co-infected. A majority [122 (54%)] of the isolates were resistant to any first-line anti-TB drugs. Among the resistant isolates, 110 (48.7%) were determined to be resistant to isoniazid, 94 (41.6%) to streptomycin, 89 (39.4%) to rifampicin, 72 (31.9%) to ethambutol, and 70 (30.9%) to pyrazinamide. The prevalence of MDR-TB was 89 (39.4%), of which 52/89 (58.4%) isolates were resistance to all five first-line drugs. Risk factors such as TB/HIV co-infection (AOR = 5.59, p = 0.00), cigarette smoking (AOR = 3.52, p = 0.045), alcohol drinking (AOR = 5.14, p = 0.001) hospital admission (AOR = 3.49, p = 0.005) and visiting (AOR = 3.34, p = 0.044) were significantly associated with MDR-TB.. The prevalence of MDR-TB in the study population was of a significantly high level among previously treated patients and age group of 25-34. TB/HIV coinfection, smoking of cigarette, alcohol drinking, hospital admission and health facility visiting were identified as risk factors for developing MDR-TB. Therefore, effective strategies should be designed considering the identified risk factors for control of MDR-TB.

Topics: Antitubercular Agents; Ethambutol; Ethiopia; Female; HIV Infections; Humans; Isoniazid; Male; Mycobacterium tuberculosis; Pyrazinamide; Rifampin; Risk Factors; Sputum; Streptomycin; Tuberculosis, Multidrug-Resistant

The emergence and spread of drug-resistant Tuberculosis (TB) is a major public health threat. TB resistance originates in the course of treatment due to genomic mutations in. A cross-sectional retrospective study was conducted on a panel of 141(n=141) MTB clinical isolates recovered between June 2010 and January 2012 from >2+ Ziehl-Neelsen smear positive new pulmonary-TB patients with no history of treatment. Frozen isolates were revived using the BACTEC MGIT detection system. DNA was extracted using GenoLyse DNA extraction kit and detection of genomic mutations was carried out using the GenoType MTBDRplus Ver 2.0 assay.. Out of the 141 isolates studied, 3 (2.1%) were found carrying mutations in the. The

Topics: Antibiotics, Antitubercular; Bacterial Proteins; Catalase; Cross-Sectional Studies; DNA-Directed RNA Polymerases; Humans; Isoniazid; Malawi; Molecular Diagnostic Techniques; Mutation; Mycobacterium tuberculosis; Oxidoreductases; Polymerase Chain Reaction; Promoter Regions, Genetic; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant

Topics: Drug Resistance, Bacterial; Humans; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Meningitis caused by Mycobacterium tuberculosis is a major cause of morbidity and mortality worldwide. We evaluated the performance of cerebrospinal fluid (CSF) testing with the GeneXpert MTB/RIF assay versus traditional approaches for diagnosing tuberculosis meningitis (TBM).. Patients were adults (n = 37) presenting with suspected TBM to the Hospital Nacional Dos de Mayo, Lima, Peru, during 12 months until 1st January 2015. Each participant had a single CSF specimen that was divided into aliquots that were concurrently tested for M. tuberculosis using GeneXpert, Ziehl-Neelsen smear and culture on solid and liquid media. Drug susceptibility testing used Mycobacteria Growth Indicator Tube (MGIT 960) and the proportions method.. 81% (30/37) of patients received a final clinical diagnosis of TBM, of whom 63% (19/30, 95% confidence intervals, CI: 44-80%) were HIV-positive. 22% (8/37, 95%CI: 9.8-38%), of patients had definite TBM. Because definite TBM was defined by positivity in any laboratory test, all laboratory tests had 100% specificity. Considering the 30 patients who had a clinical diagnosis of TBM: diagnostic sensitivity was 23% (7/30, 95%CI: 9.9-42%) for GeneXpert and was the same for all culture results combined; considerably greater than 7% (2/30, 95%CI: 0.82-22%) for microscopy; whereas all laboratory tests had poor negative predictive values (20-23%). Considering only the 8 patients with definite TBM: diagnostic sensitivity was 88% (7/8, 95%CI: 47-100%) for GeneXpert; 75% (6/8, 95%CI: 35-97%) for MGIT culture or LJ culture; 50% (4/8, 95%CI 16-84) for Ogawa culture and 25% (2/8, 95%CI: 3.2-65%) for microscopy. GeneXpert and microscopy provided same-day results, whereas culture took 20-56 days. GeneXpert provided same-day rifampicin-susceptibility results, whereas culture-based testing took 32-71 days. 38% (3/8, 95%CI: 8.5-76%) of patients with definite TBM with data had evidence of drug-resistant TB, but 73% (22/30) of all clinically diagnosed TBM (definite, probable, and possible TBM) had no drug-susceptibility results available.. Compared with traditional culture-based methods of CSF testing, GeneXpert had similar yield and faster results for both the detection of M. tuberculosis and drug-susceptibility testing. Including use of the GeneXpert has the capacity to improve the diagnosis of TBM cases.

Topics: Adolescent; Adult; Antitubercular Agents; Autoanalysis; Cerebrospinal Fluid; Clinical Laboratory Techniques; Drug Resistance, Bacterial; Female; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Reproducibility of Results; Rifampin; Sensitivity and Specificity; Tuberculosis, Meningeal; Tuberculosis, Multidrug-Resistant; Young Adult

India has the world's highest estimated burden of multi-drug-resistant tuberculosis (MDR-TB). While prevalence of MDR-TB is known to be 2-3% among new TB patients and 12-17% in previously treated patients, programmatic information on the extent of transmission of TB and MDR-TB among household contacts of known MDR-TB patients is scarce. Systematic screening of household contacts of all MDR-TB patients on treatment was implemented as an intervention in the states of Andhra Pradesh and Telangana states of India. We undertook this prospective interventional study to measure the extent of TB symptoms developed among the household contacts of the known MDR-TB patients treated under Revised National TB Control Programme (RNTCP). The extent of rifampicin sensitive or resistance TB, bacteriologically confirmed using Xpert MTB-RIF, was examined among the symptomatic household contacts.. All MDR-TB patients registered and on treatment under RNTCP between July 2011 and Sep 2013 in Andhra Pradesh and Telangana States were selected for the study. They were contacted through home visit by the trained RNTCP teams during 11th Dec 2013 and 7th Jan 2014. All household contacts of MDR-TB patients were screened once for TB symptoms such as cough, fever, weight loss, night sweats, and haemoptysis and extra pulmonary site specific symptoms if any. If found symptomatic, two sputum specimen were collected (spot-morning) from each of the contact and transported for testing on Xpert MTB-RIF for detection of pulmonary TB with or without RR-TB.. A total of 1750 MDR-TB patients were registered between July 2011 and Sep 2013. Of these, 1602 (91.5%) MDR-TB patients were included in the study. A total of 4858 household contacts of these 1602 patients were identified with an average of 3 contacts per MDR-TB patient. Of these, after excluding 87 (1.8%) contacts with past history of diagnosis and/or treatment for TB, 4771 (98.2%) contacts were screened for current signs and symptoms suggestive of TB. Their mean age was 28.5 years and 2151 (45%) were females. Of the 4771 contacts screened, 793 (16.6%) had at least one of the symptoms suggestive of TB of whom 781 (98.5%) had two sputum specimen transported and tested on Xpert MTB-Rif. Specimen could not be collected during the study period in 12 symptomatic patients including 4 with symptoms of extra pulmonary TB. Among 781 symptomatic contacts examined, 34 (4.4%) were bacteriologically confirmed with TB and 15 (44%) also had Rif resistance (RR).. High extent of TB, particularly RR-TB was observed among household contacts of known MDR-TB patients with symptom screening and early diagnosis using Xpert-MTB-Rif. Regular systematic active screening for TB and MDR-TB among this highly vulnerable group using Xpert-MTB-Rif is useful in India for early diagnosis among close contacts of known MDR-TB patients.

Topics: Adolescent; Adult; Aged; Antibiotics, Antitubercular; Child; Child, Preschool; Contact Tracing; Drug Resistance, Bacterial; Family Characteristics; Female; Humans; India; Male; Mass Screening; Middle Aged; Mycobacterium tuberculosis; Prospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Curable disease tuberculosis is becoming incurable or difficult to treat due to drug resistance. Multi drug resistance tuberculosis is a major health problem for less developed countries. Development of drug resistance is mainly as result of man related factors and poor lifestyle. Identifying predictors of drug resistance and working on them is the important way of reducing the expansion in high burden countries. Ethiopia is one of TB, TB/HIV, and multi-drug resistant tuberculosis (MDR-TB) high burden country globally. This study was aimed to assess predictor of MDR-TB in southwest part of Ethiopia.. Unmatched case control study was conducted in case to control ratio of 1:1.2 in southwest part of Ethiopia. The cases were recruited from confirmed MDR-TB patient enrolled on second line treatment in Shenen Gibe Hospital (MDR-TB treatment center of the prefecture) and the controls were recruited from previously TB patients who cured or patient with smear negative at the end of treatment month during the study period in the same area. The data was collected by structured questionnaire by interview and logistic regression analyses were used to identify predictors of MDR-TB. Odds ratios with 95% CI were computed to determine the predictors.. From the total 132 participants about 45% of them were cases. None disclosed tuberculosis infected to relatives [AOR = 3.4, 95% CI (1.2-9.8)], insufficient instruction on how to take anti-TB drug [AOR = 4.7, 95% CI (1.4-14.6)], contact history with MDR-TB [AOR = 8.5, 95% CI (2.9-25.5)], interruption of first-line anti-TB treatment for at list 1 day [AOR = 7.9, 95% CI (2.5-24.9)], and having alcohol drinking habits [AOR = 5.1, 95% CI (1.4-18.7)] were identified predictors for MDR-TB infection in study area.. TB infection disclosure status, insufficient instruction on drug usage, contact history with MDR-TB, interruption of first-line anti-TB drugs, and alcohol drinking habits were identified predictor of MDR-TB case. Therefore, early detection and proper treatment of drug susceptible TB, strengthening directly observed treatment, short-course on daily bases, community involvement, and supporting the patient to intervene identified factors is paramount.

Topics: Adolescent; Adult; Antitubercular Agents; Case-Control Studies; Child; Drug Resistance, Multiple, Bacterial; Early Diagnosis; Ethiopia; Female; Humans; Isoniazid; Male; Mycobacterium tuberculosis; Rifampin; Surveys and Questionnaires; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

Topics: Antitubercular Agents; Humans; India; Isoniazid; Rifampin; Tuberculosis, Multidrug-Resistant

Drug resistance is a leading concern in control of TB. Resistance against rifampin as one of the most important drugs in the treatment of. This study was conducted on referred samples of patients who did not respond to anti-TB treatment, in Tuberculosis Regional Reference Laboratory at Shariati Hospital. Drug susceptibility of M. tuberculosis isolates was surveyed using a proportional method on LJ medium. The isolates with resistant to rifampin were reconfirmed and then the rpoB gene was amplified and sequenced.. Among 27 resistant cases, 8, 11 and 8 people were from Iran, Afghanistan, and Turkmenistan, respectively. In 26 out of 27 isolates, rpoB gene mutations were observed. The most prevalent mutations belonged to the codon 53.. The use of rpoB gene sequencing led to the lack of the need for growth of the organism in the culture medium, the direct use of clinical samples, reduction of biological risks and a detection about 96.3% of MDR TB cases lowering the cost of the treatment.

Topics: Adult; Antitubercular Agents; Bacterial Proteins; Codon; DNA-Directed RNA Polymerases; Drug Resistance, Bacterial; Female; Genes, Bacterial; Humans; Iran; Male; Microbial Sensitivity Tests; Middle Aged; Mutation; Mycobacterium tuberculosis; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant; Young Adult

Pakistan ranks fourth among the countries with a high burden of multidrug-resistant tuberculosis (MDR-TB), with only 19.2% of the 15 000 estimated incident cases being notified. Increasing treatment coverage for MDR-TB is a key priority for Pakistan's National Tuberculosis Programme. The World Health Organization recommends the use of the Xpert® MTB/RIF assay as the first-line diagnostic test for individuals with presumed TB.. To describe a multifaceted case-finding intervention targeting public and private sector health care facilities that used the Xpert assay as a frontline diagnostic test for individuals with presumptive TB, in Karachi, Pakistan, and its impact on case notifications of MDR-TB.. Cross-sectional study.. A total of 51 168 individuals were tested using Xpert, of whom respectively 7581 and 1534 people were diagnosed with TB in the public sector (reverse public-private mix) and private sector (social business model) arms; 574 (6.3% of all TB cases) were identified as having rifampicin (RMP) resistance. A total of 517 (90.1%) people with RMP-resistant TB (RR-TB) identified through the project were initiated on second-line treatment. The intervention resulted in 194 additional cases of RR-TB, an increase of 43% over the baseline.. This project, one of the largest Xpert testing programmes conducted at city level, resulted in significantly increased detection and treatment of MDR-TB.

Topics: Antibiotics, Antitubercular; Cross-Sectional Studies; Drug Resistance, Bacterial; Humans; Microbial Sensitivity Tests; Pakistan; Private Sector; Public Sector; Rifampin; Tuberculosis, Multidrug-Resistant

Cape Town, South Africa.. To model the diagnosis of rifampicin-resistant tuberculosis (RR-TB) and laboratory costs of smear/culture and Xpert-based algorithms and the effect of varying adherence and human immunodeficiency virus (HIV) testing in the Xpert-based algorithm.. We used a validated operational model (100 000 population) and published laboratory cost data. We estimated the number and cost of RR-TB cases identified using the smear/culture- and Xpert-based algorithms. We modelled varying adherence and different levels of known HIV status against the Xpert-based algorithm.. The number of RR-TB cases identified increased from 603 with smear/culture to 1178 with the Xpert-based algorithm (100% adherence; 60% knew their HIV status). The overall laboratory cost increased from US$1 073 858 to US$2 430 050 and the cost per RR-TB case identified increased from US$1781 to US$2063 in the respective algorithms. When adherence to the Xpert-based algorithm was increased from 50% to 100% (60% knew their HIV status), the number of RR-TB cases identified increased from 721 to 1178.. The Xpert-based algorithm is efficient in identifying RR-TB, as the increase in costs is offset by the increase in the number of cases identified. Adherence to the Xpert-based algorithm is important to ensure that all presumptive TB cases receive the benefit of simultaneous TB and RR-TB testing.

Topics: Algorithms; Antibiotics, Antitubercular; Costs and Cost Analysis; Diagnostic Techniques and Procedures; HIV Infections; Humans; Models, Economic; Rifampin; South Africa; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Adverse drug reactions (ADRs) are common during standard, long-course treatment for multidrug-resistant and rifampicin-resistant tuberculosis (MDR-/RR-TB). In particular, second-line injectables (SLIs) are associated with permanent hearing loss, acute renal injury and electrolyte imbalance. We adapted an established Markov model for ambulatory treatment to estimate the impact of the toxicity profile on the incremental cost-effectiveness ratio (ICER) for a proposed MDR-/RR-TB regimen replacing the SLI with bedaquiline (BDQ).. Treatment effectiveness was evaluated in disability-adjusted life-years (DALYs). Clinical outcomes and ingredient costs from a provider perspective were derived from the South African public-sector treatment program or extracted from the literature. Costs and effectiveness were discounted at 3% per year over 10 years.. A BDQ-based MDR-/RR-TB regimen compared with the SLI regimen had a mean ICER of US$516 per DALY averted using the standard Markov model. Costs for both regimens increased and effectiveness decreased for the SLI regimen once adjusted for toxicity. The resulting ICER for the BDQ-based regimen was cost saving (US$96/patient) and more effective (0.96 DALYs averted) after adjusting for ADRs.. Decision-analysis models of treatment for MDR-/RR-TB, including new drug regimens, should consider the costs of managing ADRs and their sequelae.

Topics: Antitubercular Agents; Cost-Benefit Analysis; Diarylquinolines; Drug Costs; Health Care Costs; Humans; Markov Chains; Quality-Adjusted Life Years; Rifampin; South Africa; Treatment Outcome; Tuberculosis, Multidrug-Resistant

In Zimbabwe, while the Xpert MTB/RIF assay is being used for diagnosing tuberculosis and rifampicin-resistance, re-treatment tuberculosis (TB) patients are still expected to have culture and drug sensitivity testing (CDST) performed at national reference laboratories for confirmation. The study aim was to document the Xpert MTB/RIF assay scale-up and assess how the CDST system functioned for re-treatment TB patients.. We performed an ecologic study using national aggregate data.. Use of the Xpert MTB/RIF assay increased from 11 829 to 68 153 between 2012 and 2016. Xpert assays worked well, with successful tests in more than 90% of cases, TB detection rates at 15-17% and rifampicin resistance in <10%. During Xpert scale-up, the number of sputum specimens from re-treatment TB patients reaching national reference laboratories for CDST increased from 12% to 51%. In terms of laboratory performance, culture contamination increased from 3% to 17%, positive cultures from 13% to 17% and successful CDST from 6% to 14%: the proportion of CDST showing any resistance to rifampicin averaged 44%. From 2009 to 2016, the proportion of notified re-treatment TB patients with successful CDST increased from <1% to 7%.. While components of Zimbabwe's CDST system for re-treatment TB patients showed some changes during the scale-up of the Xpert MTB/RIF assay, overall performance was poor. The country must either invest in improving CDST performance or in advanced molecular diagnostic technology.

Topics: Antibiotics, Antitubercular; Health Surveys; Humans; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Public Health; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant; Zimbabwe

Timely diagnosis of drug-resistant tuberculosis (DR-TB) is beneficial for case treatment and management. We implemented an algorithm to improve molecular diagnostic utilization to intensify DR-TB case findings. The GeneXpert MTB/RIF (Xpert) test was used for initial diagnosis. Samples with Mycobacterium tuberculosis complex (MTBC)-positive and rifampicin resistance (RR) results were subsequently and simultaneously tested using the GenoType MTBDRplus (DRplus) and MTBDRsl (DRsl) tests. This prospective cohort study enrolled 2957 high-risk DR-TB cases. We tested sputum specimens using conventional mycobacteriological and molecular tests. Gene sequencing was performed to resolve discordant results. According to the Xpert test, 33.6% of specimens were MTBC-positive and 5.1% were RR. RR specimens were further analyzed in the DRplus and DRsl tests. We identified 1 extensively drug-resistant (XDR), 8 pre-XDR, 18 simple multidrug-resistant (MDR), 22 mono-RR, and 2 RR cases with concurrent second-line injection DR-TB. Of these, 25 (49%) were relapses, 13 (25.5%) were treatment failures, 10 (19.6%) were from MDR-TB high-incidence areas/countries, 1 was from MDR-TB contact and 2 were unknown. Among culture-positive TB cases, the sensitivities, specificities, and positive predictive values (PPVs) of the Xpert test and RR cases were 73.6% and 100.0%, 85.7% and 98.6%, and 73.5% and 80.0%, respectively. Gene sequencing of discordant results revealed 7 disputed rpoB mutations and 2 silent mutations for RIF, 1 ahpC mutation for isoniazid and 1 gyrA mutation for fluoroquinolone. The algorithm effectively identified approximately 23% of annual MDR-/XDR-TB and 37.5% of RR-TB cases that were enrolled in our DR-TB treatment and management program within 3 days.

Topics: Adult; Aged; Algorithms; Antitubercular Agents; Communicable Disease Control; Drug Resistance, Bacterial; Female; Fluoroquinolones; Genotype; Humans; Incidence; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Mutation; Mycobacterium tuberculosis; Predictive Value of Tests; Prospective Studies; Rifampin; Sequence Analysis, DNA; Taiwan; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Multidrug resistant TB (MDR-TB), defined as resistance to at least rifampicin and isoniazid together, has been rapidly spreading in recent years. In new pulmonary tuberculosis patients, rapid spread of MDR-TB and XDR-TB challenging the effectiveness of national TB control programs especially in many low-income countries. This study was aimed to determine the resistance pattern of Mycobacterium tuberculosis among new cases, cured, failure, relapse, defaulted, treatment completed, treatment not evaluated and suspect to be resistant to first line antitubercular drugs of pulmonary tuberculosis (PTB).. The study was conducted during 2013-2016 in which 148 patients were enrolled infected with pulmonary TB. Three sputum samples were consecutively collected and transported for drug analysis to the Provincial Reference Laboratory (PRL) at Hayatabad Medical complex Peshawar (HMCP) TB laboratory, within three days of collection at +4°C in a cold box. Using the standard proportion method, drug susceptibility test was performed on 132 (89.2%) sputum samples for rifampicin (R), isoniazid (H), pyrazinamide (Z), ethambutol (E), and streptomycin (S).. Prevalence of resistance to one drug was 5 (3.4%). The highest proportion of mono-drug resistance was observed against E, 3 (2%), followed by H, 1 (0.7%), and R, 1 (0.7%). Pattern of resistant to two drugs was 14 (9.5%). The proportion of poly resistant was 3 (2%). 112 (93.33%) diagnose patients were MDR-TB.. To formulate an effective regimen, it is important to know drug resistant pattern because drug resistant pattern varies from different period of time also from one place to another.

Topics: Adult; Antitubercular Agents; Ethambutol; Female; Humans; Isoniazid; Male; Mycobacterium tuberculosis; Pakistan; Prevalence; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

The increasing prevalence of drug-resistant tuberculosis (TB) infection represents a global public health emergency. We evaluated the usefulness of a newly developed multiplexed, bead-based bioassay (Quantamatrix Multiplexed Assay Platform [QMAP], QuantaMatrix, Seoul, Korea) to rapidly identify the Mycobacterium tuberculosis complex (MTBC) and detect rifampicin (RIF) and isoniazid (INH) resistance-associated mutations.. A total of 200 clinical isolates from respiratory samples were used. Phenotypic anti-TB drug susceptibility testing (DST) results were compared with those of the QMAP system, reverse blot hybridization (REBA) MTB-MDR assay, and gene sequencing analysis.. Compared with the phenotypic DST results, the sensitivity and specificity of the QMAP system were 96.4% (106/110; 95% confidence interval [CI] 0.9072-0.9888) and 80.0% (72/90; 95% CI 0.7052-0.8705), respectively, for RIF resistance and 75.0% (108/144; 95% CI 0.6731-0.8139) and 96.4% (54/56; 95% CI 0.8718-0.9972), respectively, for INH resistance. The agreement rates between the QMAP system and REBA MTB-MDR assay for RIF and INH resistance detection were 97.6% (121/124; 95% CI 0.9282-0.9949) and 99.1% (109/110; 95% CI 0.9453-1.0000), respectively. Comparison between the QMAP system and gene sequencing analysis showed an overall agreement of 100% for RIF resistance (110/110; 95% CI 0.9711-1.0000) and INH resistance (124/124; 95% CI 0.9743-1.0000).. The QMAP system may serve as a useful screening method for identifying and accurately discriminating MTBC from non-tuberculous mycobacteria, as well as determining RIF- and INH-resistant MTB strains.

Topics: Antitubercular Agents; DNA, Bacterial; Drug Resistance, Bacterial; Humans; Isoniazid; Multiplex Polymerase Chain Reaction; Mycobacterium tuberculosis; Nontuberculous Mycobacteria; Rifampin; Sequence Analysis, DNA; Tuberculosis, Multidrug-Resistant

This study was undertaken to evaluate the efficiency of the pyrosequencing (PSQ) assay for the rapid detection of resistance to rifampicin (RIF), fluoroquinolones (FQs) and second-line injectables (SLIs) such as capreomycin (CAP) and kanamycin (KAN) in Mycobacterium tuberculosis (Mtb) clinical isolates.. Pyrosequencing is a simple and accurate short read DNA sequencing method for genome analysis. DNA extraction from Mtb clinical isolates was performed using Tris-HCl buffer and chloroform. The rpoB (RIF), gyrA (FQs) and rrs (aminoglycosides) genes were amplified, followed by sequencing using the PyroMark Q24 ID system. The PSQ results were compared with the results from the conventional drug susceptibility testing performed in the laboratory.. The sensitivity of the PSQ assay for the detection of resistance to RIF, FQ, CAP and KAN was 100 %, 100 %, 40 % and 50 %, respectively. The specificity of the PSQ assay was 100 %.. The PSQ assay is a rapid and effective method for detecting drug resistance mutations from Mtb clinical isolates in a short period of time.

Topics: Antitubercular Agents; Bacterial Proteins; Drug Resistance, Multiple, Bacterial; High-Throughput Nucleotide Sequencing; Humans; Kanamycin; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

To evaluate direct drug susceptibility testing on MGIT 960 system for detection of multidrug resistant tuberculosis from smear positive pulmonary specimens.. Cross-sectional analytical study.. Microbiology Department, Armed Forces Institute of Pathology, Rawalpindi, from July 2016 to September 2017.. Smear positive specimens were pretreated according to guidelines and then tested on MGIT 960 TB system for direct drug susceptibility testing (DST) of isoniazid and rifampin. Samples were also processed by gold standard indirect method, which comprises culture and then DST from positive growth by MGIT 960 TB system.. Out of 108 specimens, 95 (88%) DST results were reportable. Out of 95 reportable specimens, 17 isolates were resistant to both isoniazid (INH) and rifampin (RIF) by direct DST. The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy for INH were 92%, 93%, 82%, 97% and 92.6%, respectively; and 95%, 96%, 86.3%, 98.6% and 95.7%, respectively for RIF. Average time to report DST by indirect method was 23.6 ±3.9 days, while it was 11.4 ±2.7 days for the direct method.. Direct susceptibility testing on MGIT 960 system showed very good agreement when compared with indirect method. Time saving is crucial factor in initiation of early effective therapy, especially in drug resistant cases. Further studies on large scale are required for more accurate evaluation of this method.

Topics: Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Female; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Predictive Value of Tests; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant

We proposed to: 1) introduce an intermediate-susceptible, dose-dependent (ISDD) category for Mycobacterium tuberculosis infection; and 2) treat patients with M. tuberculosis infection in this category with a high dose of rifampicin (RMP) and isoniazid (INH).. To examine the impact of our strategy on quality-adjusted life-years (QALY) and costs in a low-income country with a high prevalence of multidrug-resistant tuberculosis (MDR-TB) (Belarus) and a high-income, low MDR-TB prevalence country (The Netherlands).. A Markov model comprising 14 health states was used to simulate treatment outcomes and costs accrued over 5 years for a hypothetical cohort of 10 000 patients. One-way sensitivity analysis, probabilistic sensitivity analysis and a scenario analysis were also performed.. Our strategy was shown to be cost-effective for Belarus, but not for the Netherlands. At a willingness-to-pay of 50 000 euros per QALY, the probability of our strategy being cost-effective was 50% for the Netherlands and 57% for Belarus.. The study shows that our strategy could be cost-effective and more efficacious. However, more studies are needed on the outcomes of using higher doses of INH and RMP.

Topics: Antitubercular Agents; Cohort Studies; Cost-Benefit Analysis; Dose-Response Relationship, Drug; Drug Costs; Humans; Isoniazid; Markov Chains; Mycobacterium tuberculosis; Netherlands; Quality-Adjusted Life Years; Rifampin; Treatment Outcome; Tuberculosis; Tuberculosis, Multidrug-Resistant

Most epidemiological studies on Mycobacterium tuberculosis focus on pulmonary tuberculosis (TB), whereas extra-pulmonary TB (EPTB) remains poorly explored.. To study the rate of resistant EPTB cases among individuals with suspected EPTB using a commercial line-probe assay (LPA), polymerase chain reaction (PCR) and reverse hybridisation test. We also examined the molecular profile of the EPTB isolates obtained at the Himalayan Institute of Medical Sciences, Dehradun, India.. EPTB samples were collected from 249 patients with clinical and radiological suspicion of EPTB and subjected to automated liquid culture, PCR and GenoType MDRTBplus according to the manufacturers' instructions.. A diagnostic yield of 15% was observed among individuals with suspected EPTB using MGIT™ (Mycobacterium Growth Indicator Tubes), which increased to 38% on LPA and PCR. LPA results had 100% concordance with MGIT, with all culture-positive samples also being positive on LPA. However, 70.2% of LPA-positive samples did not grow Mycobacterium tuberculosis in liquid culture. Two (2.1%) of the culture-negative EPTB PCR-positive samples were multidrug-resistant, 20 (21.2%) were rifampicin-monoresistant and 12 (12.7%) isoniazid-monoresistant on LPA.. Given the paucibacillary nature of EPTB, we demonstrated that PCR and LPA can have a vital role in establishing TB diagnosis in extra-pulmonary tissues.

Topics: Antitubercular Agents; Bacteriological Techniques; Cross-Sectional Studies; Drug Resistance, Bacterial; Early Diagnosis; Genotype; Humans; India; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Polymerase Chain Reaction; Rifampin; Tertiary Care Centers; Tuberculosis, Multidrug-Resistant

The diagnosis of tuberculosis and its treatment is challenging in resource - limited settings. The growth and speed of multi drug - resistant tuberculosis (MDR-TB) in high burden countries like Nigeria is a growing concern. This study is aimed at determining the prevalence of rifampicin resistance in sputum specimens of patients with pulmonary tuberculosis in Yenagoa, Nigeria.. A descriptive survey of all consecutive sputum specimens of adults greater than 15 years of age that presented to the Tuberculosis Referral Hospital Laboratory were subjected to the automated Genexpert test between January and December 2016.. All 446 specimens were tested using the Genexpert automated system. 102 (22.9%) of the sputum specimens were positive for Mycobacterium tuberculosis, with 15 (14.7%) showing rifampicin resistance.. There was significantly high prevalence of MDR-TB much higher than the World Health Organisation (WHO) prediction of 3.2 -5.4% for Nigeria.Pan African Medical Journal - ISSN: 1937- 8688 (www.panafrican-med-journal.com)Published in partnership with the African Field Epidemiology Network (AFENET). (www.afenet.net)Pan African Medical Journal - ISSN: 1937- 8688 (www.panafrican-med-journal.com)Published in partnership with the African Field Epidemiology Network (AFENET). (www.afenet.net).

Topics: Adolescent; Adult; Antitubercular Agents; Humans; Mycobacterium tuberculosis; Nigeria; Nucleic Acid Amplification Techniques; Prevalence; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

In Cameroon, tuberculosis (TB) cases are diagnosed and treated within a nationwide network of 248 diagnostic and treatment centres. In 2016, the centers notified a total of 175 multidrug-resistant (MDR-)TB cases, most of them retreatment cases. According to the WHO, the expected number of MDR-TB cases was estimated to be 1200 (1000-2200) corresponding to a rate of 6.8 (4.3-9.4) per 100,000 population. This indicates a notification gap of more than 80%. The objective of this study was to estimate the prevalence of MDR-TB in new bacteriologically confirmed pulmonary TB cases. We undertook a nationwide cross sectional survey during 6 weeks.. During the study period, the NTP notified 1478 new bacteriologically confirmed pulmonary TB cases. Among them, 1029 (70%) had a valid Xpert result and 16 were identified with rifampicin resistant (RR-TB), a tracer of MDR-TB. This gives a prevalence of 1.6% (95% CI 0.8-2.3) among incident cases. The rate of RR-TB in the regions varied between 0 and 3.3%. If the results of this study are confirmed, the incidence rate given by WHO (2.8%, 95% CI 2.1-3.4) might be an over-estimation.

Topics: Adolescent; Antitubercular Agents; Cameroon; Cross-Sectional Studies; Female; Humans; Male; Mycobacterium tuberculosis; Rifampin; Surveys and Questionnaires; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

Topics: Adjuvants, Immunologic; Anti-Bacterial Agents; Antitubercular Agents; Cell Line; Drug Therapy, Combination; Ethambutol; Glutathione; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Pyrazinamide; Rifampin; THP-1 Cells; Tuberculosis; Tuberculosis, Multidrug-Resistant

South Africa has the highest tuberculosis incidence globally (781/100,000), with an estimated 4.3% of cases being rifampicin resistant (RR). Control and elimination strategies will require detailed spatial information to understand where drug-resistant tuberculosis exists and why it persists in those communities. We demonstrate a method to enable drug-resistant tuberculosis monitoring by identifying high-burden communities in the Western Cape Province using routinely collected laboratory data.. We retrospectively identified cases of microbiologically confirmed tuberculosis and RR-tuberculosis from all biological samples submitted for tuberculosis testing (n = 2,219,891) to the Western Cape National Health Laboratory Services (NHLS) between January 1, 2008, and June 30, 2013. Because the NHLS database lacks unique patient identifiers, we performed a series of record-linking processes to match specimen records to individual patients. We counted an individual as having a single disease episode if their positive samples came from within two years of each other. Cases were aggregated by clinic location (n = 302) to estimate the percentage of tuberculosis cases with rifampicin resistance per clinic. We used inverse distance weighting (IDW) to produce heatmaps of the RR-tuberculosis percentage across the province. Regression was used to estimate annual changes in the RR-tuberculosis percentage by clinic, and estimated average size and direction of change was mapped. We identified 799,779 individuals who had specimens submitted from mappable clinics for testing, of whom 222,735 (27.8%) had microbiologically confirmed tuberculosis. The study population was 43% female, the median age was 36 years (IQR 27-44), and 10,255 (4.6%, 95% CI: 4.6-4.7) cases had documented rifampicin resistance. Among individuals with microbiologically confirmed tuberculosis, 8,947 (4.0%) had more than one disease episode during the study period. The percentage of tuberculosis cases with rifampicin resistance documented among these individuals was 11.4% (95% CI: 10.7-12.0). Overall, the percentage of tuberculosis cases that were RR-tuberculosis was spatially heterogeneous, ranging from 0% to 25% across the province. Our maps reveal significant yearly fluctuations in RR-tuberculosis percentages at several locations. Additionally, the directions of change over time in RR-tuberculosis percentage were not uniform. The main limitation of this study is the lack of unique patient identifiers in the NHLS database, rendering findings to be estimates reliant on the accuracy of the person-matching algorithm.. Our maps reveal striking spatial and temporal heterogeneity in RR-tuberculosis percentages across this province. We demonstrate the potential to monitor RR-tuberculosis spatially and temporally with routinely collected laboratory data, enabling improved resource targeting and more rapid locally appropriate interventions.

Topics: Adult; Antitubercular Agents; Data Collection; Epidemiological Monitoring; Female; Geographic Information Systems; Humans; Incidence; Isoniazid; Male; Retrospective Studies; Rifampin; South Africa; Spatio-Temporal Analysis; Tuberculosis, Multidrug-Resistant

Self-administered treatment (SAT), a differentiated model of care for rifampicin-resistant tuberculosis (RR-TB), might address adherence challenges faced by patients and health care systems. This study explored patient, health-care worker (HCW) and community care worker (CCW) perspectives on a SAT pilot programme in South Africa, in which patients were given medication to take at home with the optional support of a CCW.. We conducted a mixed-methods study from July 2016-June 2017. The quantitative component included semi-structured questionnaires with patients, HCWs and CCWs; the qualitative component involved in-depth interviews with patients enrolled in the pilot programme. Interviews were conducted in isiXhosa, translated, transcribed and manually coded.. Overall, 27 patients, 12 HCWs and 44 CCWs were enrolled in the quantitative component; nine patients were also interviewed. Of the 27 patients who completed semi-structured questionnaires, 22 were HIV-infected and 17 received a monthly supply of RR TB treatment. Most HCWs and CCWs (10 and 32, respectively) understood the pilot programme; approximately half (n = 14) of the patients could not correctly describe the pilot programme. Overall, 11 and 41 HCWs and CCWs reported that the pilot programme promoted treatment adherence. Additionally, 11 HCWs reported that the pilot programme relieved pressure on the clinic. Key qualitative findings highlighted the importance of a support person and how the flexibility of SAT enabled integration of treatment into their daily routines and reduced time spent in clinics. The pilot programme was also perceived to allow patients more autonomy and made it easier for them to manage side-effects.. The SAT pilot programme was acceptable from the perspective of patients, HCWs and CCWs and should be considered as a differentiated model of care for RR-TB, particularly in settings with high burdens of HIV, in order to ease management of treatment for patients and health-care providers.

Topics: Adult; Attitude to Health; Community Networks; Female; Health Knowledge, Attitudes, Practice; Health Personnel; Humans; Longitudinal Studies; Male; Middle Aged; Patient Compliance; Patients; Rifampin; Self Care; South Africa; Surveys and Questionnaires; Tuberculosis; Tuberculosis, Multidrug-Resistant

New therapeutic strategies are needed to treat drug resistant tuberculosis (TB) and to improve treatment for drug sensitive TB. Pyrazinamide (PZA) is a critical component of current first-line TB therapy. However, the rise in PZA-resistant TB cases jeopardizes the future utility of PZA. To address this problem, we used the guinea pig model of TB and tested the efficacy of an inhaled dry powder combination, referred to as Pyrazinoic acid/ester Dry Powder (PDP), which is comprised of pyrazinoic acid (POA), the active moiety of PZA, and pyrazinoic acid ester (PAE), which is a PZA analog. Both POA and PAE have the advantage of being able to act on PZA-resistant Mycobacterium tuberculosis. When used in combination with oral rifampicin (R), inhaled PDP had striking effects on tissue pathology. Effects were observed in lungs, the site of delivery, but also in the spleen and liver indicating both local and systemic effects of inhaled PDP. Tissue granulomas that harbor M. tuberculosis in a persistent state are a hallmark of TB and they pose a challenge for therapy. Compared to other treatments, which preferentially cleared non-necrotic granulomas, R+PDP reduced necrotic granulomas more effectively. The increased ability of R+PDP to act on more recalcitrant necrotic granulomas suggests a novel mechanism of action. The results presented in this report reveal the potential for developing therapies involving POA that are optimized to target necrotic as well as non-necrotic granulomas as a means of achieving more complete sterilization of M. tuberculosis bacilli and preventing disease relapse when therapy ends.

Topics: Aerosols; Animals; Antitubercular Agents; Bacterial Load; Disease Models, Animal; Drug Therapy, Combination; Dry Powder Inhalers; Granuloma, Respiratory Tract; Guinea Pigs; Male; Mycobacterium tuberculosis; Necrosis; Pyrazinamide; Respiratory Tract Absorption; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Treatment success rates of rifampicin resistant (RR)/multi-drug resistant (MDR) tuberculosis (TB) in South Africa range from 43-48%, falling short of the World Health Organization's target of ≥75%. We present rates and assess predictors of attrition by 12 months on treatment.. Prospective observational cohort analysis of adults (≥18 years) initiating RR/MDR-TB treatment from 01 March 2013 to 30 September 2016. Attrition was defined as a combination of death and loss to follow-up (LTFU; treatment interruption ≥2 months) by 12 months on treatment. Predictors of attrition were identified using Cox Proportional Hazards models to estimate crude (HR) and adjusted hazard ratios (aHR) with corresponding 95% confidence intervals.. By 12 months on treatment, 75/240 (31.3%) patients had either died (37/240; 15.4%) or been LTFU (38/240; 15.8%). Patients with moderate/severe anaemia (aHR: 2.10; 95% CI 1.00-4.39), and those who were smear positive at baseline (aHR: 2.04; 95% CI 1.01-4.12) were significantly more likely to die or be lost from care.. At this outpatient DR-TB treatment site, there was a high rate of attrition halfway through the standard treatment course at 12 months of 31%. High rates of attrition by 12 months on treatment may continue during the second-half of therapy.

Topics: Adolescent; Adult; Anemia; Antitubercular Agents; Drug Administration Schedule; Drug Resistance, Bacterial; Female; Humans; Kaplan-Meier Estimate; Male; Medication Adherence; Middle Aged; Observational Studies as Topic; Proportional Hazards Models; Prospective Studies; Rifampin; Severity of Illness Index; Tuberculosis; Tuberculosis, Multidrug-Resistant; Young Adult

Topics: Antitubercular Agents; Disease Outbreaks; Humans; Rifampin; South Africa; Tuberculosis, Multidrug-Resistant

The detection of multidrug-resistant tuberculosis (MDR-TB) using rapid drug susceptibility testing (DST) has increased steadily in recent years in Peru, from 9216 tests in 2010 to 27 021 tests in 2015. Research examining the impact of rapid DST on treatment outcomes is required.. To evaluate the association between rapid DST use (nitrate reductase assay, microscopic observation drug susceptibility assay [MODS] and GenoType. Retrospective cohort study of patients diagnosed with pulmonary MDR-TB between 2010 and 2013 (with treatment outcomes up to December 2015) using the electronic registry of the Peruvian National TB Programme.. A total of 2671 MDR-TB patients were included; the median age was 27 years, 2.8% were co-infected with the human immunodeficiency virus. Use of rapid DST was associated with a 40% increase in the adjusted odds of treatment success (aOR 1.40, 95%CI 1.19-1.64) and a 54% reduction in mortality (aOR 0.46, 95%CI 0.33-0.64). Higher treatment success rates were driven by MODS and GenoType. The use of rapid DST (MODS and MTBDR

Topics: Adolescent; Adult; Antitubercular Agents; Coinfection; Female; HIV Infections; Humans; Isoniazid; Logistic Models; Male; Microbial Sensitivity Tests; Middle Aged; Multivariate Analysis; Mycobacterium tuberculosis; Peru; Registries; Retrospective Studies; Rifampin; Time-to-Treatment; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Young Adult

The diagnosis of multidrug-resistant tuberculosis (MDR-TB) and gaps in linkage to care are the principal health challenges in Mozambique. Five GeneXpert machines and GxAlert, an eHealth platform, were installed in Sofala and Manica Provinces between 2012 and 2014.. We conducted a retrospective clinical review of patients with RR-TB from March 2012 to September 2015 at these five sites. Time-series analyses were conducted to investigate the impact of Xpert on case detection and treatment. Pre- and post- analyses were conducted to investigate the impact of GxAlert.. A total of 32 182 Xpert tests were conducted: 4010 (12.5%) detected TB without rifampin resistance, and 306 (7.1%) had RR-TB. Of the RR-TB cases, 161 (52.6%) were started on MDR-TB treatment, 6.9% had documented culture results, and time from diagnosis to treatment initiation decreased over time. The absolute number of patients diagnosed and started on MDR-TB treatment increased by 0.26 (95%CI 0.15-0.38,. Implementation of Xpert testing was associated with increases in the number of patients diagnosed and started on MDR-TB treatment.

Topics: Adult; Antibiotics, Antitubercular; Bacterial Proteins; DNA, Bacterial; Drug Resistance, Bacterial; Female; Humans; Male; Middle Aged; Molecular Diagnostic Techniques; Mozambique; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant; Young Adult

In low-income countries of the Horn of Africa, pulmonary infections are usually considered as tuberculosis, which diagnosis relies on clinical data and positive microscopic observation. This strategy allows non-tuberculous mycobacteria to escape detection, facilitating their emergence in populations. A non-tuberculous mycobacterium strain FB-527 was unexpectedly cultured from the sputum of a Djiboutian patient otherwise diagnosed with multi-drug resistant (MDR) tuberculosis. The sequencing of the rpoB and 16S rRNA genes showed that the isolate was identical to strain FI-09026 previously named "Mycobacterium simulans" and reported only once from a Somali patient. Strain FB-527 mimicked Mycobacterium tuberculosis colonies and enzymatic profile using API ZYM strip and was in vitro resistant to rifampicin and isoniazid. Isolation of two MDR mycobacteria complicated the diagnosis and therapeutic management of the patient. We here report on the complete description of strain FB-527 and strain FI-09026 including genome sequencing, finalizing the description of the proposed new species "Mycobacterium simulans".

Topics: Adult; Africa; Antitubercular Agents; Bacterial Proteins; Drug Resistance, Multiple, Bacterial; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Nontuberculous Mycobacteria; Phenotype; Phylogeny; Rifampin; RNA, Ribosomal, 16S; Sputum; Tuberculosis, Multidrug-Resistant

In 2011, South Africa improved its ability to test for rifampicin-resistant TB (RR-TB) by introducing GeneXpert MTB/RIF. At the same time, the South African National TB program adopted a policy decentralized, outpatient treatment for drug resistant (DR-) TB. We aim to analyze the impact of these changes on linkage to care and DR-TB treatment outcomes.. We retrospectively matched adult patients diagnosed with laboratory-confirmed RR-TB in Johannesburg from 07/2011-06/2012 (early cohort) and 07/2013-06/2014 (late cohort) with records of patients initiating DR-TB treatment at one of the city's four public sector treatment sites. We determine the proportion of persons diagnosed with RR-TB who initiated DR-TB treatment and report time to treatment initiation (TTI) before and after the implementation of Xpert MTB/RIF roll-out in Johannesburg, South Africa. We conducted a sub-analysis among those who initiated DR-TB treatment at the decentralized outpatient DR-TB centers to determine if delays in treatment initiation have a subsequent impact on treatment outcomes.. Five hundred ninety four patients were enrolled in the early cohort versus 713 in the late cohort. 53.8 and 36.8% of patients were diagnosed with multi-drug resistant TB in the early and late cohorts, respectively. The proportion of RR-TB confirmed cases diagnosed by Xpert MTB/RIF increased from 43.4 to 60.5% between the early and late cohorts, respectively. The proportion who initiated treatment increased from 43.1% (n = 256) to 60.3% (n = 430) in the late cohort. Pre-treatment mortality during the early and the late cohort reduced significantly from 17.5 to 5.8% while lost to follow-up remained high. Although TTI reduced by a median of 19 days, from 33 days (IQR 12-52) in the early cohort to 14 days (IQR 7-31) in the late cohort, this did not translate to improved treatment outcomes and we found no difference in terms of treatment success or on-treatment mortality for those that initiated without delay vs. those that deferred initiation.. Pre-treatment mortality reduced significantly during late Xpert MTB/RIF coverage but there was no significant difference after treatment was initiated. Despite improvements there is still a significant diagnosis and treatment gap for patients diagnosed with RR-TB and improving treatment outcomes remains critical.

Topics: Adult; Aged; Antibiotics, Antitubercular; Cohort Studies; Delayed Diagnosis; Female; Humans; Male; Middle Aged; Molecular Diagnostic Techniques; Mycobacterium tuberculosis; Public Sector; Referral and Consultation; Retrospective Studies; Rifampin; South Africa; Time-to-Treatment; Treatment Outcome; Tuberculosis, Multidrug-Resistant

For lowering prevalence of drug resistance it is necessary to diagnose TB in tuberculosis sputum suspect patients instead of TB-cultured samples which required a long time of culturing. Comparison of the results of drug resistant bacterial genes in both tuberculosis suspect sputum and multi-drug resistant DNA isolates detected by MAS-PCR. In the current study, the genetic mutations linked with INH, RIF as well as EMB drugs were detected by MAS-PCR simultaneously in MDR as well as TB suspect sputum isolates. 175/291 samples belonged to MDR and 116/291 samples belonged to tuberculosis suspect group. In all the isolates, presence of Mycobacterium tuberculosis-species (100%) was confirmed by targeting hupB gene. In MDR group, maximum prevalence of gene mutation was detected in rpoB531 (92.57%) and embB306 (97.71%) while in TB-suspect group, equal percentage (96.55%) of mutation was detected in rpoB531 and embB306 by MAS-PCR. Collectively, rpoB531 (n=274, 94.15%) and embB306 (n=283, 97.25%) mutation were observed in maximum tuberculosis cases. MAS-PCR technique yielded reliable results and showed massive Isoniazid, Rifampicin and Ethambutol drugs resistance in TB-isolates from Pakistan; hence it can be used in clinical laboratories with high burden of tuberculosis to detect drug resistance rapidly and cost effectively.

Topics: Alleles; Antitubercular Agents; Humans; Isoniazid; Multiplex Polymerase Chain Reaction; Mutation; Mycobacterium tuberculosis; Pakistan; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant

Lebanon hosts a heterogeneous population coming from underdeveloped and developing countries, resulting in increasing incidences of tuberculosis over the past years. The genetic heterogeneity and lineages associated with tuberculosis, along with their resistance determinants have not been studied at the genomic level previously in the region.. Isolates were recovered from the American University of Beirut Medical Center (AUBMC). Antimicrobial susceptibility profiles were determined using the MGIT automated system for the first-line drugs at AUBMC, while second-line drug susceptibility was tested at Mayo Clinic Laboratories. Whole Genome Sequencing (WGS) was performed to classify mycobacterial lineages and highlight single nucleotide mutations causing resistance to both 1st line and 2nd line antimicrobials. wgSNP analysis provided insights on the phylogeny of the isolates along with spoligotyping and core genomic SNVs, IS6110 insertion sites, and variable number tandem repeats (VNTR).. The analyzed isolates carry distinct resistance determinants to isoniazid, rifampicin, ethambutol, quinolones, and streptomycin. The isolates belonged to different lineages including the Euro/American lineage (Lineage 4) (53.8%), M. bovis (15.4%) and Delhi/Central Asia (Lineage 1) (15.4%), Beijing/East Asia (Lineage 2) (7.7%), and East Africa/Indian Ocean lineage (Lineage 3) (7.7%) showing great phylogenetic differences at the genomic level.. The population diversity in Lebanon holds an equally diverse and uncharacterized population of drug resistant mycobacteria. To achieve the WHO "END-TB" milestones of 2025 and 2035, Lebanon must decrease TB incidences by 95% in the next decade. This can only be done through WGS-based patient centered diagnosis with higher throughput and genomic resolution to improve treatment outcomes and to monitor transmission patterns.

Topics: Adult; Bacterial Typing Techniques; Female; Genetic Variation; Genotype; Humans; Isoniazid; Lebanon; Male; Middle Aged; Minisatellite Repeats; Mutation; Mycobacterium tuberculosis; Phylogeny; Polymorphism, Single Nucleotide; Rifampin; Tuberculosis, Multidrug-Resistant

Nigeria is one of the 30 high burden countries for drug resistant tuberculosis (DR-TB). This study assessed the prevalence and factors associated with rifampicin resistant tuberculosis (RR-TB) in a secondary referral hospital in Lagos State Nigeria.. A total of 2497 clients were screened for MTB and RR-TB during the study period. The majority (51.4%) were between 25 - 44 years. Male: Female ratio was 1:0.8. Of the 2497 clients screened, MTB was detected in 942 (37.7%) out of which 220 (23.4%) had RR-TB. Age (AOR 1.8, 95%CI 1.3- 2.6, p = 0.001), symptomatic contact with DR-TB patients (AOR 3.3, 95%CI 2.1-5.1, p <0.001) and type of TB (AOR 2.9, 95% CI 1.7 - 5.0, <0.001) were associated with RR-TB after adjusting for age, gender, HIV status and symptomatic contacts with DR-TB patients.. The prevalence of RR-TB in new and previously treated TB patients was high in this study. Urgent steps are needed to avert an impending RR-TB epidemic.

Topics: Adult; Aged; Antibiotics, Antitubercular; Female; Humans; Male; Middle Aged; Mycobacterium tuberculosis; Nigeria; Polymerase Chain Reaction; Prevalence; Retrospective Studies; Rifampin; Sequence Analysis, DNA; Tuberculosis; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

Delayed diagnosis and treatment initiation of smear-negative tuberculosis (TB) patients can lead to increased morbidity and mortality, particularly among those co-infected with the human immunodeficiency virus (HIV).. Patient records of the dates and results of sputum analysis were extracted from TB laboratory registers and linked to those on treatment initiation as indicated in the TB treatment registers. The proportion of smear-negative presumptive patients who initiated anti-tuberculosis treatment was compared before and after Xpert implementation using χ² tests. Time to treatment was analysed using Kaplan-Meier survival analysis.. Xpert testing was associated with improved TB treatment initiation among smear-negative presumptive TB patients. Improved utilisation and linkage to treatment could improve the impact of this test on patient-centred outcomes.

Topics: Adolescent; Adult; Antibiotics, Antitubercular; Coinfection; Female; HIV Infections; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Molecular Diagnostic Techniques; Mycobacterium tuberculosis; Rifampin; Sputum; Survival Analysis; Tuberculosis, Multidrug-Resistant; Uganda; Young Adult

New anti-tuberculosis (anti-TB) drugs are urgently needed to battle drug-resistant Mycobacterium tuberculosis strains and to shorten the current 6-12-month treatment regimen. In this work, we have continued the efforts to develop chalcone-based anti-TB compounds by using an in silico design and QSAR-driven approach. Initially, we developed SAR rules and binary QSAR models using literature data for targeted design of new heteroaryl chalcone compounds with anti-TB activity. Using these models, we prioritized 33 compounds for synthesis and biological evaluation. As a result, 10 heteroaryl chalcone compounds (4, 8, 9, 11, 13, 17-20, and 23) were found to exhibit nanomolar activity against replicating mycobacteria, low micromolar activity against nonreplicating bacteria, and nanomolar and micromolar against rifampin (RMP) and isoniazid (INH) monoresistant strains (rRMP and rINH) (<1 μM and <10 μM, respectively). The series also show low activity against commensal bacteria and generally show good selectivity toward M. tuberculosis, with very low cytotoxicity against Vero cells (SI = 11-545). Our results suggest that our designed heteroaryl chalcone compounds, due to their high potency and selectivity, are promising anti-TB agents.

Topics: Animals; Antitubercular Agents; Chalcone; Chlorocebus aethiops; Dose-Response Relationship, Drug; Drug Design; Drug Discovery; Microbial Sensitivity Tests; Molecular Structure; Mycobacterium tuberculosis; Quantitative Structure-Activity Relationship; Tuberculosis, Multidrug-Resistant; Vero Cells

Topics: Antibiotics, Antitubercular; Antitubercular Agents; Extensively Drug-Resistant Tuberculosis; Humans; Isoniazid; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Alternative treatment strategies have become essential in overcoming the problem of drug-resistant Mycobacterium tuberculosis (Mtb). In this preliminary in vitro study, the anti-tuberculosis (anti-TB) activity of exogenous iron chelators (xenosiderophores) such as Exochelin-MS (Exo-MS) and Deferoxamine-B (DFO-B) was evaluated against ten multi-drug-resistant (MDR) and seven pyrazinamide-resistant (PZA. Mycobacteria Growth Indicator Tube-Drug Susceptibility Test was used to assess the anti-TB effect of Exo-MS or DFO-B individually and their combinations with isoniazid (INH), rifampicin (RIF) and pyrazinamide (PZA).. For the MDR-Mtb isolates, Exo-MS alone inhibited two out of the five isolates tested. Whereas, DFO-B alone inhibited nine out of the ten MDR isolates tested. For PZA-resistant Mtb isolates, both Exo-MS and DFO-B individually inhibited five out of the seven isolates. The MIC of Exo-MS in combination with INH, RIF and PZA remained the same. The MIC of DFO-B decreased when tested in combination with INH, RIF and PZA.. Exo-MS and DFO-B were shown to have activity against drug-resistant Mtb isolates. Therefore, these xenosiderophores may be useful adjuncts to antibiotics in overcoming the problem of drug-resistant Mtb in clinical setting.

Topics: Antitubercular Agents; Drug Evaluation, Preclinical; Drug Resistance, Bacterial; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Siderophores; Tuberculosis, Multidrug-Resistant

Antimicrobial resistance is a major global concern. Tuberculosis (TB) strains resistant to rifampicin and other TB medicines challenge patient survival and public health. The World Health Organization (WHO) has published treatment guidelines for drug-resistant TB since 1997 and last updated them in 2016 based on reviews of aggregated and individual patient data from published and unpublished studies. An international expert panel formulated recommendations following the GRADE approach. The new WHO guidelines recommend a standardised 9-12 months shorter treatment regimen as first choice in patients with multidrug- or rifampicin-resistant TB (MDR/RR-TB) strains not resistant to fluoroquinolones or second-line injectable agents; resistance to these two classes of core second-line medicines is rapidly detectable with molecular diagnostics also approved by WHO in 2016. The composition of longer regimens for patients ineligible for the shorter regimen was modified. A first-ever meta-analysis of individual paediatric patient data allowed treatment recommendations for childhood MDR/RR-TB to be made. Delamanid is now also recommended in patients aged 6-17 years. Partial lung resection is a recommended option in MDR/RR-TB care. The 2016 revision highlighted the continued shortage of high-quality evidence and implementation research, and reiterated the need for clinical trials and best-practice studies to improve MDR/RR-TB patient treatment outcomes and strengthen policy.

Topics: Antitubercular Agents; Disease Management; Drug Administration Schedule; Humans; Mycobacterium tuberculosis; Practice Guidelines as Topic; Rifampin; Tuberculosis, Multidrug-Resistant; World Health Organization

We describe the population structure of a representative collection of 3,133 Mycobacterium tuberculosis isolates, collected within the framework of a national resistance survey from 2007 in China. Genotyping data indicate that the epidemic strains in China can be divided into seven major complexes, of which 92% belonged to the East Asian (mainly Beijing strains) or the Euro-American lineage. The epidemic Beijing strains in China are closely related to the Beijing B0/W148 strain earlier described in Russia and a large cluster of these strains has spread national wide. The density of Beijing strains is high in the whole of China (average 70%), but the highest prevalence was found North of the Yellow river. The Euro-American lineage consists of three sublineages (sublineage_1, 2, and 3) and is more prevalent in the South. Beijing lineage showed the highest cluster rate of 48% and a significantly higher level of resistance to rifampicin (14%, p<0.001), ethambutol (9%, p = 0.001), and ofloxacin (5%, p = 0.011). Within the Euro-American Lineage, sublineage_3 revealed the highest cluster rate (28%) and presented a significantly elevated level of resistance to streptomycin (44%, p<0.001). Our findings suggest that standardised treatment in this region may have contributed to the successful spread of certain strains: sublineage_3 in the Euro-American lineage may have thrived when streptomycin was used without rifampicin for treatment, while later under DOTS based treatment, in which rifampicin plays a key role, Beijing lineage appears to be spreading.

Topics: Antitubercular Agents; China; Genotype; Humans; Microbial Sensitivity Tests; Minisatellite Repeats; Mycobacterium tuberculosis; Rifampin; Streptomycin; Surveys and Questionnaires; Tuberculosis, Multidrug-Resistant

Despite recent diagnostic advances, the majority of multidrug-resistant tuberculosis (MDR-TB) cases remain undiagnosed. Line probes assays (LiPAs) hold great promise to curb the spread of MDR-TB as they can rapidly detect MDR-TB even when laboratory infrastructure is limited, yet few of these assays are currently widely available or supported by World Health Organization (WHO) policy.. The aim of this prospective, blinded, non-inferiority study was to compare the performance of YD Diagnostics REBA MTB MDR LiPA (YD) to the WHO-endorsed Hain MTBDRplus V1 LiPA (Hain V1) for the detection of rifampicin and isoniazid resistance. In phase 1, YD and Hain V1 diagnostic performance was assessed with selected culture isolates and results were compared to phenotypic drug susceptibility testing (DST) results and targeted sequencing data. In phase 2, both assays were tested on processed sputum samples and results were compared to phenotypic DST results.. In phase 1, YD did not achieve non-inferiority to Hain V1. For isoniazid resistance detection, Hain V1 had a sensitivity of 89% (95%CI 83.8-93%) and specificity of 99.4% (95%CI 96.9-100%). While YD had a similar sensitivity of 92% (95%CI 87.3-95.4%), the specificity was inferior at 92.6% (95%CI 87.6-96%). For rifampicin resistance detection, Hain V1 had a sensitivity of 90.2% (95%CI 84.8-94.2%) and specificity of 98.5% (95%CI 95.7-99.7%) while YD had an inferior sensitivity of 72.4% (95%CI 65.1-78.9%) and a comparable specificity of 98% (95%CI 95-99.5%). Similar results were observed in phase 2. For MDR-TB detection, the sensitivity and specificity of Hain V1 was 93.4% (95%CI 88.2-96.2%) and 96.2% (95%CI 88.2-96.8%), respectively, compared to 75.7% (95%CI 68-82.2%) and 92% (95%CI 88.2-94.9%) for YD.. YD did not achieve non-inferiority with Hain V1. Further improvements and repeat evaluation of YD is necessary prior to recommending its use for clinical settings.

Topics: Antitubercular Agents; Humans; Isoniazid; Microbial Sensitivity Tests; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

In Côte d'Ivoire, multidrug-resistant tuberculosis (MDR-TB) is a serious public health problem with a prevalence estimated at 2.5% in 2006. Zinc and copper are essential Trace element needed to strengthen the immune system and also useful in the fight against tuberculosis. The Cu / Zn ratio is a good indicator of oxidative stress. The principal aim of this study was to evaluate the serum concentration of some trace element and determine the Cu / Zn ratio in patients with multidrug resistant pulmonary tuberculosis (MDR-TB) before and after second line treatment of TB.. Blood samples were obtained from 100 MDR-TB patients after confirmation of their status through the microscopic and molecular diagnosis of resistance to Isoniazid and Rifampicin by GeneXpert. The concentration level of zinc and copper were determined using flame air / acetylene atomic absorption spectrometer (AAS) Type Varian Spectr AA-20 Victoria, Australlia.. A significant decrease in zinc levels (P < 0.05) and an increased Cu / Zn ratio (P < 0.05) was observed in MDR-TB patients compared to controls TB free. During treatment a significant reduction in Cu / Zn ratio (P < 0.05) was observed compared to the initial result.. The decrease in serum zinc level and the high Cu / Zn ratio could explain the immune system dysfunction and the high level of oxidative stress in patients with MDR-TB. Therefore the evaluation of the zinc and copper status could represent essential parameters in monitoring of TB second line treatment for better treatment management.

Topics: Adolescent; Adult; Antitubercular Agents; Copper; Cote d'Ivoire; Female; Humans; Isoniazid; Male; Middle Aged; Oxidative Stress; Prevalence; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Victoria; Young Adult; Zinc

Multidrug-resistant tuberculosis (MDR-TB) is considered to be less transmissible due to the fitness cost associated with drug resistance-conferring mutations in essential genes.. To test the hypothesis that TB drug resistance-conferring mutations with fitness cost are more frequent among human immunodeficiency virus (HIV) positive than among HIV-negative patients.. We analysed all strains from the two TB drug resistance surveys conducted in Uganda between 2008 and 2011. Strains phenotypically susceptible to rifampicin and/or isoniazid were assumed to be wild-type; in all other cases, we performed whole-genome sequencing. Mutations at the rpoB531 and katG315 codons were considered without fitness loss, whereas other rpoB codons and non-katG were considered with fitness loss.. Of the 897 TB patients, 286 (32.1%) were HIV-positive. Mutations with fitness loss in HIV-positive and HIV-negative patients were respectively as follows: non-531 rpoB: 1.03% (n = 3), 0.71% (n = 4) (OR 1.46, 95%CI 0.58-3.68); non-katG: 0.40% (n = 1), 1.0% (n = 6) (OR 0.40, 95%CI 0.07-2.20); rpoB531: 1.49% (n = 4), 0.69% (n = 4) (OR 2.29, 95%CI 0.83-5.77); katG315: 3.86% (n = 11), 2.55% (n = 15) (OR 1.54, 95%CI 0.81-2.90). The odds of mutations with and without fitness cost were higher for patients with a history of previous anti-tuberculosis treatment.. Our data do not support the hypothesis that resistance-conferring mutations with fitness cost are likely to be often present in HIV-positive individuals.

Topics: Adolescent; Adult; Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Female; Genome, Bacterial; HIV Infections; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Mutation; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant; Uganda; Young Adult

Multi drug resistant tuberculosis (MDR-TB) poses formidable challenges to TB control due to its complex diagnostic and treatment challenges and often associated with a high rate of mortality. Accurate and rapid detection of MDR-TB is critical for timely initiation of treatment. Line Probe Assay (LPA) is a qualitative in vitro diagnostic test based on DNA-STRIP technology for the identification of the M. tuberculosis complex and its resistance to rifampicin (RMP) and/or isoniazid (INH). Hain Lifescience, GmbH, Germany has improved the sensitivity of Genotype MTBDRplus VER 2.0 LPA for the detection of MDR-TB; with the possibility of applying the tool in smear negative sputum samples.. A cross sectional study was conducted on 274 presumptive MDR-TB patients referred to the National TB Reference Laboratory (NTRL), Ethiopian Public Health Institute (EPHI) who submitted sputum samples for laboratory diagnosis of drug resistant-TB testing. Seventy-two smear and culture positive samples processed in smear positive direct LPA category and 197 smear negative sputum samples were processed for direct LPA. Among the smear negative samples 145 (73.6%) were culture negative and 26 (13.2%) were culture positive. All specimens were processed using NALC-NaOH method and ZN smear microscopy done from sediments. Genotype MTBDRplus VER 2.0 done from processed sputum sediments and the result was compared against the reference, BACTEC MGIT 960 culture and DST. Sensitivity, specificity, PPV and NPV of Genotype MTBDRplus VER 2.0 assay was determined and P-value <0.05 was considered as statistically significant.. The sensitivity, specificity, PPV and NPV of Genotype MTBDRplus VER 2.0 LPA were 96.4, 100, 100 and 96.9%, respectively for the detection of MDR-TB from direct smear positive sputum samples. The sensitivity, specificity, PPV and NPV of Genotype MTBDR plus VER 2.0 LPA were 77.8, 97.2, 82.4 and 97.2%, respectively, for the detection of M. tuberculosis from direct smear negative sputum samples. Fourteen (53.8%) samples had valid results with LPA among the 26 smear negative culture positive samples. The remaining 8 (30.8%) and 4 (15.4%) were invalid and negative with LPA, respectively. The sensitivity and specificity of Genotype MTBDRplus VER 2.0 LPA were 100% for the detection of MDR-TB among 14 direct smear negative and culture positive sputum samples. The most common mutations associated with RMP and INH resistance were S531L and S315TL, respectively. A single rare mutation (C15T/A16G) was detected for INH resistance.. The diagnostic performance of Genotype MTBDRplus VER 2.0 LPA in direct smear positive sputum sample was highly sensitive and specific for early detection of MDR-TB. However, the diagnostic performance of this molecular assay in direct smear negative sputum sample was low and showed a high level of invalid results for detection of M. tuberculosis and its resistance to RMP and/or INH so it is unlikely to implement Genotype MTBDRplus VER 2.0 for the detection of MDR-TB in direct smear negative sample in our routine settings. The sensitivity of the assay should be improved for detection of MDR-TB in direct smear negative sputum specimens.

Topics: Adult; Antitubercular Agents; Bacterial Typing Techniques; Cross-Sectional Studies; Cytodiagnosis; Early Diagnosis; Ethiopia; Female; Genotype; Humans; Isoniazid; Male; Molecular Diagnostic Techniques; Point Mutation; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant

Tuberculosis (TB) is a serious public health problem in developing countries such as Pakistan. Rapid diagnosis of TB and detection of drug resistance are very important for timely and appropriate management of multidrug-resistant TB (MDR-TB).. The purpose of this study was to determine the diagnostic efficacy of the Xpert MTB/RIF assay for rapid diagnosis of TB and detection of rifampicin (RIF) resistance in extrapulmonary and smear-negative pulmonary TB suspects.. A total of 98 bronchoalveolar lavage fluid (BALF) and 168 extrapulmonary specimens were processed by Xpert MTB/RIF. Culture results are considered as the gold standard for diagnosis of TB, and drug susceptibility testing for detection of RIF resistance. Diagnostic efficacy was measured in terms of sensitivity, specificity and positive and negative predictive values.. The Xpert MTB/RIF assay detected 40 (40.8 %) of 98 BALF of presumptive pulmonary TB and 60 (35.7 %) of 168 extrapulmonary specimens. Sensitivity and specificity of the Xpert MTB/RIF assay for detection of TB was 86 and 88.4 %, respectively. The positive predictive value was 71.5 % while negative predictive value was 95.1 %.. The Xpert MTB/RIF assay is a rapid and simple technique with high sensitivity and specificity for diagnosing TB and detecting drug resistance in extrapulmonary and smear-negative TB cases.

Topics: Bronchoalveolar Lavage Fluid; Drug Resistance, Multiple, Bacterial; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Pakistan; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Emergence of multidrug- and extensively drug-resistant tuberculosis (M/XDR-TB) is a major hurdle for TB control programs especially in developing countries like China. Resistance to fluoroquinolones is high among MDR-TB patients. Early diagnosis of MDR/pre-XDR-TB is essential for lowering transmission of drug-resistant TB and adjusting the treatment regimen.. Smear-positive sputum specimens (n = 186) were collected from Wuhan Institute for Tuberculosis Control. The DNA was extracted from the specimens and run through a Sanger sequencing assay to detect mutations associated with MDR/pre-XDR-TB including the rpoB core region for rifampicin (RIF) resistance; katG and inhA promoter for isoniazid (INH) resistance; and gyrA for fluoroquinolone (FQ) resistance. Sequencing data were compared to phenotypic Lowenstein-Jensen (L-J) proportion method drug susceptibility testing (DST) results for performance analysis.. By comparing the mutation data with phenotypic results, the detection rates of MDR-TB and pre-XDR-TB were 84.31% (43/51) and 83.33% (20/24), respectively. The sequencing assay illustrated good sensitivity for the detection of resistance to RIF (96.92%), INH (86.89%), FQ (77.50%). The specificities of the assay were 98.35% for RIF, 99.20% for INH, and 97.26% for FQ.. The sequencing assay is an efficient, accurate method for detection of MDR-TB and pre-XDR-TB from clinical smear-positive sputum specimens, should be considered as a supplemental method for obtaining early DST results before the availability of phenotypic DST results. This could be of benefit to early diagnosis, adjusting the treatment regimen and controlling transmission of drug-resistant TB.

Topics: Amino Acid Substitution; Antitubercular Agents; Bacterial Proteins; China; Early Diagnosis; Extensively Drug-Resistant Tuberculosis; Fluoroquinolones; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Promoter Regions, Genetic; Rifampin; Sensitivity and Specificity; Sequence Analysis, DNA; Sputum; Tuberculosis, Multidrug-Resistant

Simultaneous use of genotypic and phenotypic diagnostic tools for detection of rifampicin (RIF) susceptibility may yield discrepant results.. To measure the discordance between the RIF-susceptibility results by Xpert MTB/RIF and Mycobacterium Growth Indicator Tube (MGIT), to evaluate if application of both tests to the same sample affects the discrepancy, and to evaluate treatment outcome in patients with the discordant strains.. Sputa from patients with tuberculosis managed in the penitentiary system of Azerbaijan during 2011-2015 were examined for RIF susceptibility using Xpert MTB/RIF and MGIT. Strains with discrepant results were sequenced.. Of 532 patients included, 6.2% had discordant RIF-susceptibility results. No significant association of the discordant RIF-susceptibility results with application of both tests on one sample versus sequential samples was found. L511P mutation accounted significantly (p = 0.006) for the discrepancy among those RIF resistant on Xpert MTB/RIF, but sensitive on MGIT. No significant association was identified between the outcomes of treatment with the first- or second-line drugs and the presence of any mutation.. The Xpert MTB/RIF and MGIT testing may be used in sequential sputum samples without increase in the RIF-susceptibility discordance rate. L511P mutation significantly accounts for discordant RIF-susceptibility results, but its clinical relevance may be low.

Topics: Anti-Bacterial Agents; Azerbaijan; Drug Resistance, Bacterial; Humans; Mycobacterium tuberculosis; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Delayed diagnosis of tuberculosis (TB) and drug-resistant TB are major challenges of TB control in Thailand. This study assessed the practicality of the Xpert MTB/RIF assay in a real-life setting with high prevalence of human immunodeficiency virus (HIV) infection and pulmonary tuberculosis (PTB).. This prospective study was conducted at 3 large tertiary care hospitals. Patients who had suspected PTB were enrolled into the study. Expectorated sputum samples were sent for staining, mycobacterial culture, and Xpert MTB/RIF.. Four hundred ninety-four patients were enrolled. From 355 cases with final diagnosis of PTB, 263 (71.8%) had definite diagnosis and 92 cases had probable diagnosis. Among TB culture-positive cases, Xpert MTB/RIF had 100% and 81% sensitivity in sputum smear-positive and smear-negative groups, respectively. The specificity was 95.7%. The sensitivity and positive predictive value of Xpert MTB/RIF in culture-negative but clinically diagnosed PTB was 37.8% and 83.8%, respectively. Centrifugation was required in 59% cases with scanty sputum. Five cases were false-positive by Xpert MTB/RIF in patients with nontuberculous mycobacteria, old PTB scar, and immune reconstitution syndrome. Discordant rifampicin susceptibility results of Xpert MTB/RIF and mycobacteria growth indicator tube (MGIT) were confirmed by using rpoB gene sequencing, which raised the sensitivity of Xpert MTB/RIF in detecting rifampicin resistance to 93.8%.. Xpert MTB/RIF is an effective tool in diagnosing PTB but will be more cost-effective for sputum-negative patients and in settings with high prevalence of rifampicin resistance. Early diagnosis of TB results in early treatment and implementation of strategies to limit spreading of TB. Sputum centrifugation may increase the yield of Xpert MTB/RIF.

Topics: Adult; Bacterial Proteins; Coinfection; Delayed Diagnosis; DNA-Directed RNA Polymerases; Female; HIV Infections; Humans; Male; Middle Aged; Molecular Diagnostic Techniques; Mycobacterium tuberculosis; Prevalence; Prospective Studies; Rifampin; Sensitivity and Specificity; Sputum; Tertiary Care Centers; Thailand; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

The incidence of drug-resistant tuberculosis (DR-TB) in pediatric populations is a critical indicator of national TB management and treatment strategies. Limited data exist regarding the rate of pediatric DR-TB. In this study, we aimed to analyze the status of DR-TB in Korean children from 2007 to 2013. We analyzed specimens submitted to the Korean Institute of Tuberculosis using Mycobacterium tuberculosis culture and drug susceptibility tests (DSTs) from January 2007 through December 2013. Specimens from patients ≤ 19 years of age were included. Among the 2,690 cases, 297 cases were excluded because of insufficient data, leaving 2,393 cases for the final analysis. In total, resistance to one or more TB drugs was 13.5%. The resistance rates of each of the drugs were as follows: isoniazid (INH) 10.2%, rifampin (RFP) 5.1%, ethambutol (EMB) 3.7%, and pyrazinamide (PZA) 3.1%. The resistance rate of multidrug-resistant TB (MDR-TB) was 4.2%, and that of extensively drug-resistant TB (XDR-TB) was 0.8%. The overall drug resistance rate demonstrated significant increase throughout the study period (P < 0.001) but showed no significant difference compared to previous study from 1999 to 2007. The drug resistance rate of PZA in ≤ 15 years of age group was significantly greater than that of > 15 years (P < 0.001). The drug resistance rate has increased throughout the study period.

Topics: Adolescent; Antitubercular Agents; Asian People; Child; Child, Preschool; Drug Resistance, Multiple, Bacterial; Ethambutol; Female; Humans; Incidence; Infant; Isoniazid; Male; Mycobacterium tuberculosis; Pyrazinamide; Republic of Korea; Rifampin; Tuberculosis, Multidrug-Resistant; Young Adult

Topics: Antitubercular Agents; Beijing; China; DNA, Bacterial; Drug Resistance, Multiple, Bacterial; Epidemiologic Studies; Genotype; Humans; Isoniazid; Mycobacterium tuberculosis; Polymorphism, Genetic; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant

Drug-resistant tuberculosis (TB) is an emerging health problem. Rifampicin (RIF) is the major first-line drug against TB. RIF resistance can be used as a marker for the detection of multidrug-resistant TB (MDR-TB). The purpose of this study was to determine the RIF resistance pattern of Mycobacterium tuberculosis complex isolates among treated and untreated patients in Khyber Pakhtunkhwa, Pakistan.. A total of 349 drug-treated and untreated TB-diagnosed patients were enrolled in this study. RIF resistance was detected using a GeneXpert. The overall prevalence of RIF resistance was 5.2% (18/349). Among 49 untreated TB patients, 3 samples (6.1%) were found resistant to RIF. Among 235 patients with a category 1 treatment regimen, 10 samples (4.3%) were resistant to RIF, whilst among 65 patients with a category 2 (Cat-2) treatment regimen, 5 samples (7.7%) were resistant to RIF. A comparison based on patient sex revealed high RIF resistance among male compared with female patients. RIF resistance was highest (4/21; 19.0%) in the 21-40 years age group among Cat-2 patients.. The overall prevalence of RIF resistance was high among treated and untreated TB patients. These findings will be helpful for better monitoring and management of RIF resistance in TB patients from Khyber Pakhtunkhwa, Pakistan.

Topics: Adolescent; Adult; Antibiotics, Antitubercular; Child; Child, Preschool; Drug Resistance, Bacterial; Female; Genotyping Techniques; Humans; Infant; Infant, Newborn; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Pakistan; Prevalence; Rifampin; RNA Polymerase II; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

The impact of the genetic characteristics of Mycobacterium tuberculosis on the clustering of multidrug-resistant tuberculosis (MDR-TB) has not been analyzed together with clinical and demographic characteristics.. To determine factors associated with genotypic clustering of MDR-TB in a community-based study.. We measured the proportion of clustered cases among MDR-TB patients and determined the impact of clinical and demographic characteristics and that of three M. tuberculosis genetic characteristics: lineage, drug resistance-associated mutations, and rpoA and rpoC compensatory mutations.. Of 174 patients from California and Texas included in the study, the number infected by East-Asian, Euro-American, Indo-Oceanic and East-African-Indian M. tuberculosis lineages were respectively 70 (40.2%), 69 (39.7%), 33 (19.0%) and 2 (1.1%). The most common mutations associated with isoniazid and rifampin resistance were respectively katG S315T and rpoB S531L. Potential compensatory mutations in rpoA and rpoC were found in 35 isolates (20.1%). Hispanic ethnicity (OR 26.50, 95%CI 3.73-386.80), infection with an East-Asian M. tuberculosis lineage (OR 30.00, 95%CI 4.20-462.40) and rpoB mutation S531L (OR 4.03, 95%CI 1.05-23.10) were independent factors associated with genotypic clustering.. Among the bacterial factors studied, East-Asian lineage and rpoB S531L mutation were independently associated with genotypic clustering, suggesting that bacterial factors have an impact on the ability of M. tuberculosis to cause secondary cases.

Topics: Adult; Antitubercular Agents; Bacterial Proteins; California; Cluster Analysis; Drug Resistance, Multiple, Bacterial; Female; Genotype; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Mutation; Mycobacterium tuberculosis; Rifampin; Texas; Tuberculosis, Multidrug-Resistant; Young Adult

The GenoType®MTBDRplusV.2 assay is a molecular technique endorsed by the World Health Organization and the Pan American Health Organization that allows for the identification of the Mycobacterium tuberculosis complex and the detection of mutations in the rpoβ gene for rifampicin resistance, and katG and inhA genes for isoniazid resistance. Due to the genetic variability in the circulating strains around the world, the national tuberculosis control programs should assess the performance of these new diagnostic technologies and their use under program conditions as rapid tests.. To describe the mutations identified by the GenoType®MTBDRplusV.2 assay in pulmonary samples and Mycobacterium tuberculosis isolates in the Laboratorio Nacional de Referencia of the Instituto Nacional de Salud in 2014.. We conducted a retrospective, descriptive study to detect the expression of inhA, KatG and rpoβ genes, responsible for resistence against isoniazid and rifampicin using the GenoType® MTBDRplus V.2 assay in 837 samples and isolates from tuberculosis cases.. Several mutations in the rpoβ gene were identified. Ser531Leu was the most frequent (36.6%) followed by Asp516Val (21.6%), while Ser315Thr1 was the most frequent mutation in the katG gene (91.9%).. We were able to identify different mutations present in MDR-TB strains in the country, with frequencies similar to those reported in other countries in the South American region.

Topics: Antitubercular Agents; Colombia; Genotype; Genotyping Techniques; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant

One third of the increase in tuberculosis cases is attributed to the spread of HIV. In 2012, 1,397 HIV-associated tuberculosis cases were reported in Colombia, i.e., 11.8% of the total cases. Molecular epidemiology tools help to understand the transmission of tuberculosis.. To characterize clinical isolates of Mycobacterium tuberculosis derived from HIV-infected individuals, received at the Laboratorio Nacional de Referencia in the Instituto Nacional de Salud.. This was a descriptive observational study. We analyzed 63 isolates of M. tuberculosis from HIV-infected individuals. Identification, drug susceptibility and genotyping assays were performed.. Of the new cases evaluated, three (5.0%) were resistant to isoniazid combined with streptomycin; two (3.3%) to rifampicin, and one (1.6%) to isoniazid. Previously treated cases were sensitive. No multidrug resistance was evident. Among the predominant genotypes, 20 isolates were (31.7%) LAM9, eight (12.7%), H1, and seven (11.1%), T1. Nineteen isolates corresponded to orphan patterns. One single grouping was observed among tested isolates. We found no statistically significantdifference between the proportions of the antituberculous drug resistance and genotypes.. We found resistant isolates to the most powerful drugs, rifampicin and isoniazid, among new cases, showing the transmission of resistant strains. Genetic families of M. tuberculosis LAM9, T1 and H1 correspond to those described in the general population. We detected no active transmission among studied isolates. More comprehensive studies are needed to assess the real situation of HIV associated tuberculosis in the country regarding sensitivity and transmission.

Topics: Antitubercular Agents; Colombia; HIV Infections; Humans; Isoniazid; Rifampin; Streptomycin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Multidrug-resistant and rifampicin-resistant tuberculosis (MDR/RR-TB) represent an important challenge for global tuberculosis (TB) control. The high rates of MDR/RR-TB observed among re-treatment cases can arise from diverse pathways: de novo amplification during initial treatment, inappropriate treatment of undiagnosed MDR/RR-TB, relapse despite appropriate treatment, or reinfection with MDR/RR-TB. Mathematical modelling allows quantification of the contribution made by these pathways in different settings. This information provides valuable insights for TB policy-makers, allowing better contextualised solutions. However, mathematical modelling outputs need to consider local data and be easily accessible to decision makers in order to improve their usefulness. We present a user-friendly web-based modelling interface, which can be used by people without technical knowledge. Users can input their own parameter values and produce estimates for their specific setting. This innovative tool provides easy access to mathematical modelling outputs that are highly relevant to national TB control programs. In future, the same approach could be applied to a variety of modelling applications, enhancing local decision making.

Topics: Antitubercular Agents; Decision Making; Drug Resistance, Bacterial; Humans; Models, Theoretical; Precision Medicine; Retreatment; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant; User-Computer Interface

Drug-resistant tuberculosis, especially multidrug-resistant tuberculosis (MDR-TB), is a major public health problem. Effective management of MDR-TB relies on accurate and rapid diagnosis. In this study, we assessed the diagnostic accuracy of the Genotype MTBDRplus assay in diagnosing MDR-TB in Cameroon, and then discuss on its utility within the diagnostic algorithm for MDR-TB.. In this cross-sectional study, 225 isolates of Mycobacterium tuberculosis cultured from sputum samples collected from new and previously treated pulmonary tuberculosis patients in Cameroon were used to determine the accuracy of the Genotype MTBDRplus assay. We compared the results of the Genotype MTBDRplus assay with those from the automated liquid culture BACTEC MGIT 960 SIRE system for sensitivity, specificity, and degree of agreement. The pattern of mutations associated with resistance to RIF and INH were also analyzed.. The Genotype MTBDRplus assay correctly identified Rifampicin (RIF) resistance in 48/49 isolates (sensitivity, 98% [CI, 89%-100%]), Isoniazid (INH) resistance in 55/60 isolates (sensitivity 92% [CI, 82%-96%]), and MDR-TB in 46/49 (sensitivity, 94% [CI, 83%-98%]). The specificity for the detection of RIF-resistant and MDR-TB cases was 100% (CI, 98%-100%), while that of INH resistance was 99% (CI, 97%-100%). The agreement between the two tests for the detection of MDR-TB was very good (Kappa = 0.96 [CI, 0.92-1.00]). Among the 3 missed MDR-TB cases, the Genotype MTBDRplus assay classified two samples as RIF-monoresistant and one as INH monoresistant. The most frequent mutations detected by the Genotype MTBDRplus assay was the rpoB S531 L MUT3 41/49 (84%) in RIF-resistant isolates, and the KatG S315 T1 (MUT1) 35/55 (64%) and inhA C15T (MUT1) 20/55 (36%) mutations in INH-resistant isolates.. The Genotype MTBDRplus assay had good accuracy and could be used for the diagnosis of MDR-TB in Cameroon. For routine MDR-TB diagnosis, this assay could be used for Mycobacterium tuberculosis cultures containing contaminants, to complement culture-based drug susceptibility testing or to determine drug resistant mutations.

Topics: Adult; Antitubercular Agents; Bacterial Proteins; Cameroon; Cross-Sectional Studies; Female; Genotype; Genotyping Techniques; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Molecular Diagnostic Techniques; Mutation; Mutation Rate; Mycobacterium tuberculosis; Oxidoreductases; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Mycobacterium tuberculosis complex may sometimes not be detected in sputum samples of suspected multidrug-resistant tuberculosis (MDR-TB) patients by line probe assay (LPA) even though they are smear positive for acid-fast bacilli (AFB). This retrospective analysis was attempted to understand and document our experience with LPA for detection of M. tuberculosis complex and diagnosis of MDR-TB under programmatic conditions.. One thousand two hundred and ninety four sputum samples of MDR-TB suspects that were smear positive for AFB, and received from February to November 2013, were tested by LPA for the presence of M. tuberculosis complex and resistance to isoniazid (INH) and rifampicin as per the diagnostic mandate of an accredited reference laboratory. As per the mandate, those samples that were negative for M. tuberculosis complex were cultured, and the growth again tested by LPA. A retrospective analysis of the results was carried out.. M. tuberculosis complex could be detected in 1217 (94.04%) but not in 77 (5.9%) of smear-positive sputum samples. Of the 1217 positive samples, 232 (19.1%) were MDR, 130 (10.6%) were rifampicin monoresistant and 101 (8.3%) were INH monoresistant. Seven hundred and fifty four (61.9%) strains were found to be pansensitive. Overall, 5.1 per cent of the sputum samples were negative for M. tuberculosis complex by LPA and culture. In at least 10 (0.77%) sputum samples smear positive for AFB, M. tuberculosis complex could not be identified by LPA though M. tuberculosis was present, as evidenced by culture positivity.. LPA is a robust technique for diagnosis of drug-resistant TB that has provided the basis for rapid and effective control of drug-resistant TB in India. While the reasons for concomitantly negative LPA and culture results of smear-positive sputum samples from MDR-TB suspects may be many, the possible presence of non-tubercular mycobacteria in these samples and the likelihood of inappropriate therapy in these patients cannot be ruled out. Addition of culture to the diagnostic algorithm may enhance the diagnostic yield.

Topics: Female; Humans; India; Isoniazid; Male; Mycobacterium tuberculosis; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant

Slums are considered as hotspots of tuberculosis (TB). The study of genetic diversity and drug susceptibility profile of Mycobacterium tuberculosis (MTB) will help understand the transmission dynamics and can be used for better prevention and control of the disease. The aim of this study was to determine the drug susceptibility profiles and genetic diversity using the random amplified polymorphic DNA (RAPD) and mycobacterial interspersed repetitive units-variable number of tandem repeats (MIRU VNTR) of MTB isolates from sputum samples of pulmonary TB patients residing in the two slums of Jaipur city in Rajasthan, India.. Sputum samples collected from pulmonary TB patients, their contacts and suspects during 2010-2012 were processed for microscopy and mycobacterial culture. Drug susceptibility testing was done by one per cent indirect proportion method on Lowenstein-Jensen medium for first-line anti-TB drugs rifampicin, isoniazid, ethambutol and streptomycin. MTB DNA was extracted by physicochemical method, and DNA fingerprinting was done by RAPD and MIRU VNTR analysis.. Among 175 sputum samples collected, 75 were positive (43.8%) for acid-fast bacilli, 83 for MTB culture and four were contaminated. Fifty two isolates (62.7%) were fully sensitive to four drugs, and five (6%) were multidrug resistant (MDR). RAPD analysis of 81 isolates revealed six clusters containing 23 (28.4%) isolates, and 58 (71.6%) were unique. MIRU VNTR analysis clustered 20 (24.7%) isolates, and 61 (75.3%) were unique.. About 62.7 per cent isolates from the sputum samples from slum areas were sensitive to four drugs; six per cent of isolates were MDR. Poly-resistance other than MDR was high (16%). About one-fourth isolates were clustered by either method. RAPD was rapid, less expensive but had low reproducibility. MIRU VNTR analysis could identify to greater extent the epidemiological link in the population studied.

Topics: Adolescent; Adult; Aged; Child; Child, Preschool; Drug Resistance, Multiple, Bacterial; Female; Genetic Variation; Genotype; Humans; Interspersed Repetitive Sequences; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Minisatellite Repeats; Mycobacterium tuberculosis; Phylogeny; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Young Adult

To cope with the emergence of multidrug-resistant tuberculosis (MDR-TB), new molecular methods that can routinely be used to screen for a wide range of drug resistance related genetic markers in the Mycobacterium tuberculosis genome are urgently needed.. To evaluate the performance of multiplex ligaton-dependent probe amplification (MLPA) against Genotype® MTBDRplus to detect resistance to isoniazid (INHr) and rifampicin (RIFr).. 96 culture isolates characterised for identification, drug susceptibility testing (DST) and sequencing of rpoB, katG, and inhA genes were evaluated by the MLPA and Genotype®MTBDRplus assays.. With sequencing as a reference standard, sensitivity (SE) to detect INHr was 92.8% and 85.7%, and specificity (SP) was 100% and 97.5%, for MLPA and Genotype®MTBDRplus, respectively. In relation to RIFr, SE was 87.5% and 100%, and SP was 100% and 98.8%, respectively. Kappa value was identical between Genotype®MTBDRplus and MLPA compared with the standard DST and sequencing for detection of INHr [0.83 (0.75-0.91)] and RIFr [0.93 (0.88-0.98)].. Compared to Genotype®MTBDRplus, MLPA showed similar sensitivity to detect INH and RIF resistance. The results obtained by the MLPA and Genotype®MTBDRplus assays indicate that both molecular tests can be used for the rapid detection of drug-resistant TB with high accuracy. MLPA has the added value of providing information on the circulating M. tuberculosis lineages.

Topics: Antibiotics, Antitubercular; DNA, Bacterial; Drug Resistance, Multiple, Bacterial; Genotype; Humans; Isoniazid; Microbial Sensitivity Tests; Multiplex Polymerase Chain Reaction; Mycobacterium tuberculosis; Phenotype; Rifampin; Tuberculosis, Multidrug-Resistant

Pyrazinamide is used in the treatment of tuberculosis (TB) because its sterilizing effect against tubercle bacilli allows the shortening of treatment. It is part of standard treatment for drug-susceptible and drug-resistant TB, and it is being considered as a companion drug in novel regimens. The aim of this analysis was to characterize factors contributing to the variability in exposure and to evaluate drug exposures using alternative doses, thus providing evidence to support revised dosing recommendations for drug-susceptible and multidrug-resistant tuberculosis (MDR-TB). Pyrazinamide pharmacokinetic (PK) data from 61 HIV/TB-coinfected patients in South Africa were used in the analysis. The patients were administered weight-adjusted doses of pyrazinamide, rifampin, isoniazid, and ethambutol in fixed-dose combination tablets according to WHO guidelines and underwent intensive PK sampling on days 1, 8, 15, and 29. The data were interpreted using nonlinear mixed-effects modeling. PK profiles were best described using a one-compartment model with first-order elimination. Allometric scaling was applied to disposition parameters using fat-free mass. Clearance increased by 14% from the 1st day to the 29th day of treatment. More than 50% of patients with weight less than 55 kg achieved lower pyrazinamide exposures at steady state than the targeted area under the concentration-time curve from 0 to 24 h of 363 mg · h/liter. Among patients with drug-susceptible TB, adding 400 mg to the dose for those weighing 30 to 54 kg improved exposure. Average pyrazinamide exposure in different weight bands among patients with MDR-TB could be matched by administering 1,500 mg, 1,750 mg, and 2,000 mg to patients in the 33- to 50-kg, 51- to 70-kg, and greater than 70-kg weight bands, respectively.

Topics: Adolescent; Adult; Antitubercular Agents; Coinfection; Drug Combinations; Ethambutol; HIV Infections; Humans; Isoniazid; Male; Metabolic Clearance Rate; Middle Aged; Pyrazinamide; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

The differentiation of Mycobacterium tuberculosis complex (MTBC) from non-tuberculous mycobacteria (NTM) is of primary importance for infection control and the selection of anti-tuberculosis drugs. Up to date data on rifampicin (RIF)-resistant tuberculosis (TB) is essential for the early management of multidrug-resistant TB. The aim of this study was to evaluate the usefulness of a newly developed multiplexed, bead-based bioassay (Quantamatrix Multiplexed Assay Platform, QMAP) for the rapid differentiation of 23 Mycobacterium species including MTBC and RIF-resistant strains.. A total of 314 clinical Mycobacterium isolates cultured from respiratory specimens were used in this study.. The sensitivity and specificity of the QMAP system for Mycobacterium species were 100% (95% CI 99.15-100%, p<0.0001) and 97.8% (95% CI 91.86-99.87%, p<0.0001), respectively. The results of conventional drug susceptibility testing and the QMAP Dual-ID assay were completely concordant for all clinical isolates (100%, 95% CI 98.56-100%). Out of 223 M. tuberculosis (MTB) isolates, 196 were pan-susceptible and 27 were resistant to RIF according to QMAP results. All of the mutations in the RIF resistance-determining region detected by the QMAP system were confirmed by rpoB sequence analysis and a REBA MTB-Rifa reverse blot hybridization assay. The majority of the mutations (n=26, 96.3%), including those missing wild-type probe signals, were located in three codons (529-534, 524-529, and 514-520), and 17 (65.4%) of these mutations were detected by three mutation probes (531TTG, 526TAC, and 516GTC).. The entire QMAP system assay takes about 3h to complete, while results from the culture-based conventional method can take up to 48-72h. Although improvements to the QMAP system are needed for direct respiratory specimens, it may be useful for rapid screening, not only to identify and accurately discriminate MTBC from NTM, but also to identify RIF-resistant MTB strains in positive culture samples.

Topics: Bacterial Typing Techniques; Drug Resistance, Microbial; Humans; Microspheres; Mutation; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis; Tuberculosis, Multidrug-Resistant

Tuberculosis (TB) caused by Mycobacterium tuberculosis (MTB) poses a major public health problem in Nepal. Although it has been reported as one of the dominant genotypes of MTB in Nepal, little information on the Central Asian Strain (CAS) family is available, especially isolates related to multidrug resistance (MDR) cases. This study aimed to elucidate the genetic and epidemiological characteristics of MDR CAS isolates in Nepal.. A total of 145 MDR CAS isolates collected in Nepal from 2008 to 2013 were characterized by spoligotyping, mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR) analysis, and drug resistance-associated gene sequencing.. Spoligotyping analysis showed CAS1_Delhi SIT26 as predominant (60/145, 41.4%). However, by combining spoligotyping and MIRU-VNTR typing, it was possible to successfully discriminate all 145 isolates into 116 different types including 18 clusters with 47 isolates (clustering rate 32.4%). About a half of these clustered isolates shared the same genetic and geographical characteristics with other isolates in each cluster, and some of them shared rare point mutations in rpoB that are thought to be associated with rifampicin resistance.. Although the data obtained show little evidence that large outbreaks of MDR-TB caused by the CAS family have occurred in Nepal, they strongly suggest several MDR-MTB transmission cases.

Topics: Adolescent; Adult; Bacterial Proteins; Bacterial Typing Techniques; Child; Child, Preschool; DNA-Directed RNA Polymerases; DNA, Bacterial; Drug Resistance, Multiple, Bacterial; Female; Genotyping Techniques; Humans; Infant; Male; Middle Aged; Minisatellite Repeats; Mycobacterium tuberculosis; Nepal; Public Health; Rifampin; Sequence Analysis, DNA; Tuberculosis, Multidrug-Resistant; Young Adult

The DOTS strategy has been regarded as the most cost-effective way to stop the spread of tuberculosis (TB) since its launch by the World Health Organization.. To estimate the effects of DOTS by tracking long-term trends in multidrug-resistant TB (MDR-TB).. A retrospective cohort study was conducted from 2000 to 2013 to analyse trends in resistance to anti-tuberculosis drugs and the effect of DOTS-based treatment in Shenzhen, China, using the χ2 test.. An overall MDR-TB rate of 4.2% was observed between 2000 and 2013, with an annual reduction of 0.16%. From 2000 to 2013, trends in resistance to isoniazid (INH), rifampicin (RMP) and MDR-TB declined significantly in new TB patients (P < 0.01), but not in retreatment cases. Sputum smear conversion rates after 2 months of treatment decreased significantly, in particular after 2007, in new and retreatment cases.. INH and RMP resistance and MDR-TB rates declined significantly, suggesting that DOTS-based programmes were successful in reducing drug resistance in new cases but not in retreatment cases. The decreasing sputum smear conversion rates may have been due to an increase in the number of migrants. These two findings suggest that TB is unlikely to be completely eliminated by 2050 in Shenzhen.

Topics: Adolescent; Adult; Antitubercular Agents; Child; Child, Preschool; China; Cohort Studies; Directly Observed Therapy; Female; Humans; Infant; Isoniazid; Male; Middle Aged; Mycobacterium tuberculosis; Retreatment; Retrospective Studies; Rifampin; Sputum; Time Factors; Tuberculosis, Multidrug-Resistant; Young Adult

The WHO recently has recommended the GenoType MTBDRplus version 1.0 and MTBDRsl version 1.0 assays for widespread use in countries endemic with drug-resistant tuberculosis. Despite this, these assays have rarely been evaluated in China, where the burden of drug-resistant tuberculosis is among the highest globally.. Mycobacterium tuberculosis clinical isolates were obtained between January 2008 and December 2008. Isolates were tested for drug resistance against rifampicin (RFP) and isoniazid (INH) using the GenoType MTBDRplus assay and drug resistance against ethambutol (EMB), ofloxacin (OFX), and kanamycin (KM) using the Genotype MTBDRsl assay. These results were compared with conventional drug-susceptibility testing (DST).. Readable results were obtained from 235 strains by GenoType MTBDRplus assay. Compared to DST, the sensitivity of GenoType MTBDRplus assay to detect RFP, INH, and multidrug resistance was 97.7%, 69.9%, and 69.8%, respectively, whereas the specificity for detecting RFP, INH, and multidrug resistance was 66.7%, 69.2%, and 76.8%, respectively. The sensitivity and specificity of the GenoType MTBDRsl assay were 90.9% and 95.2% for OFX, 77.8% and 99.5% for KM, 63.7% and 86.4% for EMB, respectively. Mutations in codon S531L of the rpoB gene and codon S315T1 of KatG gene were dominated in multidrug-resistant tuberculosis (MDR-TB) strains.. In combination with DST, application of the GenoType MTBDRplus and MTBDRsl assays may be a useful supplementary tool to allow a rapid and safe diagnosis of multidrug resistance and extensively drug-resistant tuberculosis.

Topics: Adult; Antitubercular Agents; China; Drug Resistance, Multiple, Bacterial; Female; Genotype; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Molecular Diagnostic Techniques; Mutation; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

The various aspects of MDR-TB, type of pathogen, different drug sensitive methods and mutation (s) in specific genes were determined. The histone-like protein (hupB) gene of M. tuberculosis was targeted by using primer sets: N & S and M & S (produced 645 bp & 318 bp fragment respectively). The most significant risk factors were the poverty and male gender of ages 11-25 years. All samples were detected as M. tuberculosis. By Drug Proportion method, the highest percentage (37%) was found resistant to only Rifampin. By MGIT method, the highest percentage (82.2%) was found resistant with the triple combination (Rifampin-RIF + Isoniazid-INH + Ethambutol-EMB) of the drugs. The highest mutations (76.92%) were found in gene rpoB (codon 531) in MDR TB patients. By, MAS-PCR, the highest percentage (34%) were found resistant to combination (INH + RIF) of the drugs. Minimum samples were resistant to RIF and RIF + INH drugs by MGIT, while proportionate results were observed from MAS-PCR and DP. Moreover, by MAS-PCR mutation in gene embB (306) caused EMB resistance (51.64%). We found that M. tuberculosis was the main cause of MDR-TB. Our findings may further be used for an early diagnosis of multi-drug resistant tuberculosis.

Topics: Adolescent; Adult; Aged; Bacterial Proteins; Child; DNA-Directed RNA Polymerases; DNA, Bacterial; Ethambutol; Genes, Bacterial; Histones; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Molecular Typing; Mutation; Mycobacterium bovis; Mycobacterium tuberculosis; Pakistan; Pathology, Molecular; Pentosyltransferases; Rifampin; Risk Factors; Tuberculosis, Multidrug-Resistant; Young Adult

Topics: Antibiotics, Antitubercular; Bacterial Proteins; DNA-Directed RNA Polymerases; False Positive Reactions; Humans; Mycobacterium tuberculosis; Reagent Kits, Diagnostic; Rifampin; Sensitivity and Specificity; Tuberculosis; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Topics: Anti-Bacterial Agents; Antibiotics, Antitubercular; Clindamycin; Contraindications, Drug; Drug Administration Schedule; Drug Therapy, Combination; Fluoroquinolones; Hidradenitis Suppurativa; Humans; Moxifloxacin; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Cohort Studies; Communicable Disease Control; Drug Resistance, Bacterial; Genotype; Humans; India; Infectious Disease Medicine; Linezolid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Predictive Value of Tests; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Antituberculosis drug resistance is increasing among tuberculosis (TB) patients globally, particularly in those who are human immunodeficiency virus (HIV)-positive. The aim of this study was to determine the pattern of anti-TB drug resistance in these patients in an effort to improve successful treatment outcomes with a proper regimen.. A cross-sectional study was conducted on adult TB/HIV co-infected patients from 2005-2015. The pattern of anti-TB drug resistance was evaluated among HIV-positive patients with and without a history of TB treatment. Categorisation was made as follows: isoniazid (INH)-resistant; rifampicin (RIF)-resistant; or multidrug-resistant (MDR).. A total of 52 patients were enrolled in this study (median age 38 years). Among the 52 patients, 18 (34.6%) were MDR-TB patients and the rest were monoresistant TB (resistant either to INH or RIF). INH resistance was the most common resistance pattern (36.5%) noted among patients and was significantly associated with new TB cases (69% vs. 31%; P=0.01). During TB treatment, 3/48 patients (6.3%) failed treatment and 11/48 (22.9%) died. Patients with MDR-TB were more likely to die during treatment (44.4% vs. 10%; P=0.011).. Any drug resistance in previously treated TB cases among HIV-infected patients remains high. The risk of death is increasing in MDR-TB/HIV co-infected patients.

Topics: Adult; Antitubercular Agents; Coinfection; Cross-Sectional Studies; Drug Resistance, Multiple, Bacterial; Female; HIV Infections; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Prevalence; Rifampin; Tuberculosis, Multidrug-Resistant

In South Africa, roughly half of the drug-resistant TB cases diagnosed are reported to have been started on treatment. We determined the proportion of persons diagnosed with rifampicin resistant (RR-) TB who initiated treatment in Johannesburg after the introduction of decentralized RR-TB care in 2011.. We retrospectively matched adult patients diagnosed with laboratory-confirmed RR-TB in Johannesburg from 07/2011-06/2012 with records of patients initiating RR-TB treatment at one of the city's four public sector treatment sites (one centralized, three decentralized). Patients were followed from date of diagnosis until the earliest of RR-TB treatment initiation, death, or 6 months' follow-up. We report diagnostic methods and outcomes, proportions initiating treatment, and median time from diagnosis to treatment initiation.. 594 patients were enrolled (median age 34 (IQR 29-42), 287 (48.3%) female). Diagnosis was by GenoType MTBDRplus (Hain-Life-Science) line probe assay (LPA) (281, 47.3%), Xpert MTB/RIF (Cepheid) (258, 43.4%), or phenotypic drug susceptibility testing (DST) (30, 5.1%) with 25 (4.2%) missing a diagnosis method. 320 patients (53.8%) had multi-drug resistant TB, 158 (26.6%) rifampicin resistant TB by Xpert MTB/RIF, 102 (17.2%) rifampicin mono-resistance, and 14 (2.4%) extensively drug-resistant TB. 256/594 (43.0%) patients initiated treatment, representing 70.7% of those who were referred for treatment (362/594). 338/594 patients (57.0%) did not initiate treatment, including 104 (17.5%) who died before treatment was started. The median time from sputum collection to treatment initiation was 33 days (IQR 12-52).. Despite decentralized RR-TB treatment, fewer than half the patients diagnosed in Johannesburg initiated appropriate treatment. Offering treatment at decentralized sites alone is not sufficient; improvements in linking patients diagnosed with RR-TB to effective treatment is essential.

Topics: Adult; Antibiotics, Antitubercular; Antitubercular Agents; Female; Humans; Male; Middle Aged; Mycobacterium tuberculosis; Outcome Assessment, Health Care; Primary Health Care; Proportional Hazards Models; Public Sector; Retrospective Studies; Rifampin; South Africa; Sputum; Survival Analysis; Time Factors; Tuberculosis, Multidrug-Resistant

The objectives of this study were to analyse the frequency of gene mutations associated with antitubercular drug resistance in clinical samples from the population of Jalisco State (Mexico) and to evaluate the genetic variability of Mycobacterium tuberculosis and multidrug-resistant (MDR) M. tuberculosis strains to describe the frequency of various families.. Clinical isolates of M. tuberculosis obtained from Jalisco State were analysed. Isolates were subjected to drug susceptibility testing, and mutations were characterised by sequencing, followed by genotyping using spoligotyping and mycobacterial interspersed repetitive units-variable-number of tandem repeats (MIRU-VNTR). Moreover, the prevalence of mutations was analysed by phylogenetic lineages.. Resistant strains were analysed by sequencing of katG, inhA and rpoB genes to determine the presence of mutations associated with isoniazid and rifampicin resistance. In MDR, monoresistant and polyresistant isolates, mutations were found in 17 (54.84%) of 31 strains. Spoligotyping identified six different strain lineages [T1 (25.40%), H3 (7.94%), MANU (4.76%), X1 (3.17%), EAI5 (1.59%) and LAM1 (1.59%)], with the remaining strains identified as orphans. In additional tree-based identification, a dendrogram of spoligotype patterns generated five different similarity clusters. When combining 24-loci MIRU-VNTR and spoligotyping approaches, the results shows that there is no cluster formation, indicating low transmission of the samples.. This study using spoligotyping and MIRU-VNTR showed that the analysed strains were not related to each other since no two identical strains were found. Families with the highest prevalence in the study were orphans followed by T family.

Topics: Antitubercular Agents; Bacterial Proteins; Catalase; DNA-Directed RNA Polymerases; DNA, Bacterial; Genetic Variation; Genotyping Techniques; Humans; Isoniazid; Mexico; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Oxidoreductases; Phylogeny; Rifampin; Tuberculosis, Multidrug-Resistant

Abbott RealTime MTB (Abbott-RT) in conjunction with Abbott RealTime MTB RIF/INH Resistance (Abbott-RIF/INH) is a new, high-throughput automated nucleic acid amplification platform (Abbott-MDR) for detection of Mycobacterium tuberculosis complex (MTBC) and the genotypic markers for rifampicin (RIF) and isoniazid (INH) resistance directly from respiratory specimens. This prospective study evaluated the diagnostic performance of this new platform for MTBC and multidrug-resistant tuberculosis (MDR-TB) using 610 sputum specimens in a tuberculosis high-burden setting. Using conventional culture results and clinical background as reference standards, Abbott-RT exhibited an overall sensitivity and specificity of 95.2% and 99.8%, respectively. Genotypic RIF/INH resistance of 178 "MTB detected" specimens was subsequently analyzed by Abbott-RIF/INH. Compared to phenotypic drug susceptibility test results, Abbott-RIF/INH detected resistance genotypic markers in 84.6% MDR-TB, 80% mono-RIF-resistant and 66.7% mono-INH-resistant specimens. Two of the RIF-resistant specimens carried a novel single, nonsense mutation at rpoB Q513 and in silico simulation demonstrated that the truncated RpoB protein failed to bind with other subunits for transcription. Overall, Abbott-MDR platform provided high throughput and reliable diagnosis of MDR-TB within a TB high-burden region.

Topics: Antibiotics, Antitubercular; Bacterial Proteins; DNA-Directed RNA Polymerases; High-Throughput Screening Assays; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Prospective Studies; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant

The study aimed at assessing the Tuberculosis (TB) medication adherence level and the efficacy of smear microscopy in the diagnosing pulmonary TB at month 2.. A prospective study was conducted at the four sites located in the Northern-western Tanzania. New smear positive, pulmonary TB patients were followed up and their adherence to TB medication assessed after 2 months of the treatment. In addition, the acid fast bacilli (AFB) smear microscopy was performed after 2 and 5 months of the treatment. All smear positive samples were subjected to geneXpert (MTB/RIF) assay and culture on the Lowenstein Jensen (LJ) media.. A total of 331 smear positive, newly diagnosed patients with pulmonary TB were enrolled. The median age was 36 [Interquartile range (IQR): 28-45] years and males formed the slightly majority, 187 (56.5%) of the participants. A total of 105 (31.7%) patients were infected with HIV. Out of 331 patients, 36 (10.9%) were still AFB smear positive at the end of two month. Of these 19 (52.8%) were positive on GeneXpert MTB RIF and none was Rifampicin resistant. Of note, only 13 (31.1%) were culture positive (viable). None of the patients was positive at month 5. Poor adherence to TB medications in the first 2 months of treatment was observed in 56/331 (16.9%) [95% CI=12.9-21.0] of the patients.. Over two thirds of smear positive patients are wrongly put in one month extension of the intensive phase treatment; this may cause increased costs and drug toxicity. Culture should be advocated to confirm smear positivity after 2 months of medications. TB treatment drug adherence in our setting is good and is associated with successful cure. No multidrug resistant tuberculosis (MDR-TB) was observed. Continued surveillance and emphasizing of TB drug adherence should be kept upbeat in order to control tuberculosis in developing countries.

Topics: Adult; Drug Resistance, Multiple, Bacterial; Female; Humans; Male; Medication Adherence; Microscopy; Middle Aged; Mycobacterium tuberculosis; Prospective Studies; Rifampin; Tanzania; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; World Health Organization

Multidrug resistant tuberculosis (MDR-TB) is rising and the World Health Organization has recommended the line probe assay (LPA) for screening. In this study we assess LPA at a tertiary care centre from North India in 1758 samples from suspected MDR-TB cases. All smear-positive and/or Mycobacterium tuberculosis culture confirmed cases (n = 1170) were subjected to the GenoType-MTBDR assay. Amongst these the majority were retreatment cases, smear-positive at diagnosis (n = 637). An MDR prevalence of 7·8% was observed with the highest cases reported amongst MDR contacts (33·3%). The most common rifampicin resistance encoding mutation seen overall and in individual patient groups was H531L (53·3%). A higher prevalence of H526D mutation was observed in retreatment cases, smear-positive at 4 months of anti-tubercular therapy vs other patient groups (P = 0·052). The most common mutation encoding isoniazid resistance was S315T1 in the katG (79·9%) and C-15T in the inhA gene (91·1%). Thirty rifampicin and nine isoniazid resistant isolates had wild type gene deletion but no detectable mutation by LPA. Although LPA is a practical and rapid screening method for most mutations expected to result in MDR-TB, we observed that it only detects the known major mutations in specific genes. Such studies can provide the knowledge required to formulate customized strips based on prevalent mutations in our region and in specific patient groups.. To the best of our knowledge this is the largest study evaluating the GenoType-MTBDR line probe assay from India. We have studied the prevalence of mutations encoding rifampicin and isoniazid resistance in different patient groups based on criteria for multidrug resistance (MDR) suspicion. The translational impact of this study is in the design of customized country- or region-wise line probe assay strips. The identification of a few mutations in particular patient groups and the detection of wild type deletion mutants with no observable mutations both point toward the need for such customization enabling us to combat the rising trend of MDR tuberculosis.

Topics: Antitubercular Agents; Gene Deletion; Genotype; Humans; India; Isoniazid; Mutation; Mycobacterium tuberculosis; Polymerase Chain Reaction; Rifampin; Sequence Deletion; Tuberculosis, Multidrug-Resistant

The worldwide emergence of multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) has posed additional challenges for global tuberculosis (TB) control efforts, as limited treatment options are available and treatment outcomes are often sub-optimal. This study determined treatment outcomes among a cohort of MDR-TB and XDR-TB patients in Hunan Province, China, and identified factors associated with poor treatment outcomes.. We conducted a retrospective study using data obtained from medical records of TB patients in Hunan Chest Hospital, and from the internet-based TB management information system managed by the Tuberculosis Control Institute of Hunan Province, for the period 2011 to 2014. Treatment outcomes were assessed for patients diagnosed with MDR-TB (TB resistant to at least isoniazid and rifampicin) and XDR-TB (MDR-TB plus resistance to any fluoroquinolone and at least 1 second-line injectable drug). Cumulative incidence functions were used to estimate time to events (i.e. poor treatment outcomes, loss to follow-up, and unfavourable treatment outcomes); and a competing-risks survival regression model was used to identify predictors of treatment outcomes.. Of 481 bacteriologically-confirmed patients, with a mean age of 40 years (standard deviation SD ± 13 years), 10 (2%) had XDR-TB and the remainder (471; 98%) had MDR-TB. For the entire cohort, treatment success was 57% (n = 275); 58% (n = 272) for MDR-TB and 30% (n = 3) for XDR-TB. Overall, 27% were lost to follow-up (n = 130), 27% (n = 126) for MDR-TB and 40% (n = 4) for XDR-TB; and 16% had a poor treatment outcome (n = 76), 15% for MDR-TB and 30% (n = 3) for XDR-TB. Of the 10 XDR-TB patients, 3 (30%) completed treatment, 3 (30%) died and 4 (40%) were lost to follow-up. Of the 471 MDR-TB patients, 258 (57%) were cured, 16 (3%) completed treatment, 13 (3%) died, 60 (13%) experienced treatment failure, and 126 (27%) were lost to follow-up. Resistance to ofloxacin was an independent predictor of poor (AHR = 3.1; 95%CI = 1.5, 6.3), and unfavourable (AHR = 1.7; 95%CI = 1.07, 2.9) treatment outcomes. Patients who started treatment during 2011-2012 (AHR = 2.8; 95% CI = 1.5, 5.3) and 2013 (AHR = 2.1; 95% CI = 1.2, 3.9) had poorer treatment outcomes compared to patients who started treatment during 2014.. Patients with MDR-TB and XDR-TB had low rates of treatment success in Hunan Province, especially among patients who started treatment during 2011 to 2013, with evidence of improved treatment outcomes in 2014. Resistance to ofloxacin was an independent predictor of poor treatment outcomes.

Topics: Adult; Antitubercular Agents; China; Cohort Studies; Extensively Drug-Resistant Tuberculosis; Female; Fluoroquinolones; Humans; Isoniazid; Lost to Follow-Up; Male; Middle Aged; Ofloxacin; Retrospective Studies; Rifampin; Treatment Failure; Treatment Outcome; Tuberculosis, Multidrug-Resistant

Molecular screening of new patients suspected for TB could help in the effective control of TB in Pakistan as it is a high TB burden country. It will be informative to understand the prevalence of multi drug resistance for a better drug regimen management in this geographical area. The Rifampicin resistance determining region (RRDR) sequencing was used to identify mutations associated with drug resistance in DNA extracts from 130 known multidrug resistant (MDR) cultured strains and compared with mutations observed in DNA extracts directly from 86 sputum samples from consecutive newly diagnosed cases in Lahore, Pakistan. These newly diagnosed samples were positive for smear microscopy, chest X-ray and presumed sensitive to first line drugs. In the known MDR group the most frequent mutations conferring resistance were found in rpoB531 (n = 51, 39.2%). In the newly diagnosed tuberculosis group with no history of MDR, mutations in rpoB531 were seen in 10 of the samples (11.6%). Collectively, all mutations in the RRDR region studied were observed in 80 (61.5%) of known MDR cases and in 14 (16.3%) of the newly diagnosed cases. Using the RRDR as a surrogate marker for MDR, sequences for the newly diagnosed (presumed sensitive) group indicate much higher levels of MDR than the 3.9% WHO 2015 global estimate and suggests that molecular screening directly from sputum is urgently required to effectively address the detection and treatment gaps to combat MDR in this high burden country.

Topics: Antitubercular Agents; Bacterial Proteins; DNA-Directed RNA Polymerases; Humans; Microbial Sensitivity Tests; Mutation; Pakistan; Rifampin; Tuberculosis, Multidrug-Resistant

The Mycobacterium tuberculosis (M.tb) protein kinase B (PknB) which is now proved to be essential for the growth and survival of M.tb, is a transmembrane protein with a potential to be a good drug target. However it is not known if this target remains conserved in otherwise resistant isolates from clinical origin. The present study describes the conservation analysis of sequences covering the inhibitor binding domain of PknB to assess if it remains conserved in susceptible and resistant clinical strains of mycobacteria picked from three different geographical areas of India.. A total of 116 isolates from North, South and West India were used in the study with a variable profile of their susceptibilities towards streptomycin, isoniazid, rifampicin, ethambutol and ofloxacin. Isolates were also spoligotyped in order to find if the conservation pattern of pknB gene remain consistent or differ with different spoligotypes. The impact of variation as found in the study was analyzed using Molecular dynamics simulations.. The sequencing results with 115/116 isolates revealed the conserved nature of pknB sequences irrespective of their susceptibility status and spoligotypes. The only variation found was in one strains wherein pnkB sequence had G to A mutation at 664 position translating into a change of amino acid, Valine to Isoleucine. After analyzing the impact of this sequence variation using Molecular dynamics simulations, it was observed that the variation is causing no significant change in protein structure or the inhibitor binding.. Hence, the study endorses that PknB is an ideal target for drug development and there is no pre-existing or induced resistance with respect to the sequences involved in inhibitor binding. Also if the mutation that we are reporting for the first time is found again in subsequent work, it should be checked with phenotypic profile before drawing the conclusion that it would affect the activity in any way. Bioinformatics analysis in our study says that it has no significant effect on the binding and hence the activity of the protein.

Topics: Antitubercular Agents; Base Sequence; DNA, Bacterial; Drug Resistance, Multiple, Bacterial; Ethambutol; Genetic Variation; Humans; India; Isoniazid; Microbial Sensitivity Tests; Mitoxantrone; Molecular Docking Simulation; Mutation; Mycobacterium tuberculosis; Ofloxacin; Phenotype; Protein Serine-Threonine Kinases; Protein Structure, Tertiary; Rifampin; Sequence Analysis; Streptomycin; Tuberculosis; Tuberculosis, Multidrug-Resistant

National Institute of Diseases of the Chest and Hospital, Dhaka; Bangladesh Institute of Research and Rehabilitation in Diabetes, Endocrine and Metabolic Disorders, Dhaka; and Chittagong Chest Disease Hospital, Chittagong, Bangladesh.. To present operational data and discuss the challenges of implementing FAST (Find cases Actively, Separate safely and Treat effectively) as a tuberculosis (TB) transmission control strategy.. FAST was implemented sequentially at three hospitals.. Using Xpert® MTB/RIF, 733/6028 (12.2%, 95%CI 11.4-13.0) patients were diagnosed with unsuspected TB. Patients with a history of TB who were admitted with other lung diseases had more than twice the odds of being diagnosed with unsuspected TB as those with no history of TB (OR 2.6, 95%CI 2.2-3.0, P < 0.001). Unsuspected multidrug-resistant TB (MDR-TB) was diagnosed in 89/1415 patients (6.3%, 95%CI 5.1-7.7). Patients with unsuspected TB had nearly five times the odds of being diagnosed with MDR-TB than those admitted with a known TB diagnosis (OR 4.9, 95%CI 3.1-7.6, P < 0.001). Implementation challenges include staff shortages, diagnostic failure, supply-chain issues and reliance on external funding.. FAST implementation revealed a high frequency of unsuspected TB in hospitalized patients in Bangladesh. Patients with a previous history of TB have an increased risk of being diagnosed with unsuspected TB. Ensuring financial resources, stakeholder engagement and laboratory capacity are important for sustainability and scalability.

Topics: Bangladesh; Hospitalization; Humans; Mycobacterium tuberculosis; Prevalence; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

India is considering the scale-up of the Xpert MTB/RIF assay for detection of tuberculosis (TB) and rifampicin resistance. We conducted an economic analysis to estimate the costs of different strategies of Xpert implementation in India.. Using a decision analytical model, we compared four diagnostic strategies for TB patients: (i) sputum smear microscopy (SSM) only; (ii) Xpert as a replacement for the rapid diagnostic test currently used for SSM-positive patients at risk of drug resistance (i.e. line probe assay (LPA)); (iii) Upfront Xpert testing for patients at risk of drug resistance; and (iv) Xpert as a replacement for SSM for all patients.. The total costs associated with diagnosis for 100,000 presumptive TB cases were: (i) US$ 619,042 for SSM-only; (ii) US$ 575,377 in the LPA replacement scenario; (iii) US$ 720,523 in the SSM replacement scenario; and (iv) US$ 1,639,643 in the Xpert-for-all scenario. Total cohort costs, including treatment costs, increased by 46% from the SSM-only to the Xpert-for-all strategy, largely due to the costs associated with second-line treatment of a higher number of rifampicin-resistant patients due to increased drug-resistant TB (DR-TB) case detection. The diagnostic costs for an estimated 7.64 million presumptive TB patients would comprise (i) 19%, (ii) 17%, (iii) 22% and (iv) 50% of the annual TB control budget. Mean total costs, expressed per DR-TB case initiated on treatment, were lowest in the Xpert-for-all scenario (US$ 11,099).. The Xpert-for-all strategy would result in the greatest increase of TB and DR-TB case detection, but would also have the highest associated costs. The strategy of using Xpert only for patients at risk for DR-TB would be more affordable, but would miss DR-TB cases and the cost per true DR-TB case detected would be higher compared to the Xpert-for-all strategy. As such expanded Xpert strategy would require significant increased TB control budget to ensure that increased case detection is followed by appropriate care.

Topics: Antibiotics, Antitubercular; Biological Assay; Humans; India; Rifampin; Sputum; Tuberculosis; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Diarylquinolines; Drug Resistance, Bacterial; Humans; Mycobacterium tuberculosis; Nitroimidazoles; Oxazoles; Rifampin; Tuberculosis, Multidrug-Resistant

Multidrug-resistant tuberculosis (TB) presents a major public health dilemma. Heteroresistance, the coexistence of drug-resistant and drug-susceptible strains or of multiple drug-resistant strains with discrete haplotypes, may affect accurate diagnosis and the institution of effective treatment. Subculture, or passage of cells onto fresh growth medium, is utilized to preserve

Topics: Antitubercular Agents; Bacterial Proteins; DNA Gyrase; DNA-Directed RNA Polymerases; Drug Resistance, Multiple, Bacterial; Fluoroquinolones; High-Throughput Nucleotide Sequencing; Humans; Isoniazid; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Tuberculosis remains the leading causes of death worldwide with frequencies of mutations in rifampicin and isoniazid resistant Mycobacterium tuberculosis isolates varying according to geographical location. There is limited information in Zimbabwe on specific antibiotic resistance gene mutation patterns in MTB and hence, increased rate of discordant results and mortality due to inappropriate antibiotic prescriptions. The rpoB and katG genes molecular markers are used for detecting rifampicin and isoniazid resistance respectively. Some mutations within these gene sequences are associated with drug resistance as they directly alter gene function. The objectives of this research was to determine the drug resistance profiles in M. tuberculosis isolates that are phenotypically resistant but not detected by the GeneXpert and MTBDRplus kit and also to detect mutations in the rpoB and katG genes which are not detected by the Hain Genotype MTBDRplus kit and GeneXpert diagnosis.. PCR was used for the amplification of the rpoB and katG genes from MTB isolates collected from human clinical samples between 2008 and 2015. The genes were sequenced and compared to the wild type MTB H37Rv rpoB (accession number L27989) and kat G genes (KP46920), respectively. Sequence analysis results were compared to genotyping results obtained from molecular assays and culture results of all isolates.. The most frequent mutation responsible for rifampicin resistance was (25/92) S531L that was detected by using all molecular assays. Some inconsistencies were observed between phenotypic and genotypic assay results for both katG and rpoB genes in 30 strains. For these, eight codons; G507S, T508A, L511V, del513-526, P520P, L524L, R528H, R529Q and S531F were novel mutations. In addition, the I572P/F, E562Q, P564S, and Q490Y mutations were identified as novel mutations outside the rifampicin resistance determining region. In katG gene, amino acid changes to threonine, asparagine and isoleucine exhibited high degrees of polymorphism such as V473N, D311N, and L427I. The R463L (20/92) amino acid substitution was most common but was not associated with isoniazid resistance.. These finding indicate that molecular assay kit diagnosis that is based on the rpoB and katG genes should be improved to cater for the genetic variations associated with the geographic specificity of the target genes and be able to detect most prevalent mutations in different areas.

Topics: Adolescent; Adult; Aged; Amino Acid Substitution; Antitubercular Agents; Bacterial Proteins; Catalase; Child; DNA-Directed RNA Polymerases; Drug Resistance, Multiple, Bacterial; Female; Genotype; Humans; Isoniazid; Male; Middle Aged; Molecular Diagnostic Techniques; Mutation; Mycobacterium tuberculosis; Polymerase Chain Reaction; Rifampin; Sequence Analysis, DNA; Tuberculosis, Multidrug-Resistant; Young Adult; Zimbabwe

To describe the timing and predictors of mortality among multidrug- and rifampicin-resistant tuberculosis (MDR/RR-TB) patients reported in the South African electronic drug-resistant TB register (EDRweb), 2012-2014.. We present time-to-event survival analysis and Cox proportional hazards regression. Identity numbers were matched to the National Vital Statistics Register.. Of the 20 653 patients included in the analysis (median age 35 years, interquartile range 28-43), over half were male (n = 10 944, 53.0%). Most were human immunodeficiency virus (HIV) positive (n = 14 174, 68.9%), most of whom were on antiretroviral therapy (ART; n = 12 471, 88.0%). At 24 months, 4689 patients had died (22.7%); 2072 deaths (44.2%) were reported within 12 weeks of initiating treatment for MDR/RR-TB. From week 12 to week 24, there were 717 deaths/18 048 persons; 59.5% of mortality occurred within the first 24 weeks. During the first 12 weeks, the adjusted hazard rate (aHR) for mortality was highest among patients with a missing baseline culture result (aHR 3.78, 95%CI 2.94-4.86) and among HIV-positive, ART-naïve patients (aHR 3.40, 95%CI 2.90-3.99). Patients initiating MDR/RR-TB treatment within 4 weeks of diagnosis had higher mortality than those with delayed initiation (aHR 1.57, 95%CI 1.41-1.75).. In EDRweb, mortality is highest in the first few weeks after MDR/RR-TB treatment initiation.

Topics: Adult; Anti-HIV Agents; Antitubercular Agents; Female; HIV Infections; Humans; Male; Proportional Hazards Models; Retrospective Studies; Rifampin; South Africa; Time Factors; Tuberculosis, Multidrug-Resistant

To assess the proportion of rifampicin-resistant tuberculosis (RR-TB) patients with potential earlier RR-TB diagnoses in Khayelitsha, South Africa.. We conducted a retrospective analysis among RR-TB patients diagnosed from 2012 to 2014. Patients were considered to have missed opportunities for earlier diagnosis if 1) they were incorrectly screened according to the Western Cape diagnostic algorithm; 2) the first specimen was not tested using Xpert® MTB/RIF; 3) no specimen was ever tested; or 4) the initial Xpert test showed a negative result, but no subsequent specimen was sent for follow-up testing in human immunodeficiency virus-positive patients.. Among 543 patients, 386 (71%) were diagnosed with Xpert and 112 (21%) had had at least one presentation at a health care facility within the 6 months before the presentation at which RR-TB was diagnosed. Overall, 95/543 (18%) patients were screened incorrectly at some point: 48 at diagnostic presentation only, 38 at previous presentation only, and 9 at both previous and diagnostic presentations.. These data show that a significant proportion of RR-TB patients might have been diagnosed earlier, and suggest that case detection could be improved if diagnostic algorithms were followed more closely. Further training and monitoring is required to ensure the greatest benefit from universal Xpert implementation.

Topics: Algorithms; Antitubercular Agents; Female; Health Services Accessibility; HIV Infections; Humans; Male; Mass Screening; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; South Africa; Time Factors; Tuberculosis, Multidrug-Resistant

xtra-pulmonary tuberculosis (EPTB) is a growing public health concern, and data on drug resistance are limited.. Specimens from 2468 clinically diagnosed EPTB patients received at the Intermediate Reference Laboratory (IRL) of a tertiary centre in India were subjected to Ziehl-Neelsen staining, Xpert® MTB/RIF testing, liquid culture and drug susceptibility testing (DST) using automated BACTEC MGIT™ 960™. Line-probe assay (LPA) was performed on all culture-positive isolates. Gene sequencing was performed on rifampicin-resistant/multidrug-resistant TB (RR/MDR-TB) and phenotypic/genotypic discrepant isolates.. The culture positivity rate was 18.9% (483/2553). The sensitivity and specificity of Xpert in diagnosing EPTB were respectively 70.8% (95%CI 66.5-74.8) and 97.7% (95%CI 96.9-98.3), with liquid culture as the reference standard. Prevalence of RR/MDR-TB was 10.1% (49/483). Prevalence of pre-extensively drug-resistant TB (pre-XDR-TB) was 18.4% (09/49), whereas the prevalence of XDR-TB among MDR-TB patients was 2% (01/49). The sensitivity of genotypic DST for the detection of rifampicin resistance was 92.7% (95%CI 81.1-98.5) and specificity was 99.3% (95%CI 97.5-99.9), with 100% concordance between Xpert and LPA.. The burden of drug resistance, including M/XDR-TB, among EPTB patients is high. Novel molecular tests can help in early diagnosis and treatment to prevent disease progression and amplification of resistance.

Topics: Adult; Antitubercular Agents; Drug Resistance, Bacterial; Early Diagnosis; Extensively Drug-Resistant Tuberculosis; Female; Genotype; Humans; India; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Prevalence; Rifampin; Sensitivity and Specificity; Tertiary Care Centers; Tuberculosis, Multidrug-Resistant; Young Adult

Rifampin (RIF) mono-resistant tuberculosis (RMR-TB) is a rare disease. Current guidelines recommend that RMR-TB be treated as multidrug-resistant TB (MDR-TB) but the evidence is scarce.. We conducted a retrospective cohort study on pulmonary TB patients to investigate the characteristics and outcomes of RMR-TB. The characteristics of RMR-TB were compared with those with adverse events to rifampin (RAE-TB).. Forty-four RMR-TB and 29 RAE-TB patients were enrolled. RMR-TB patients showed more alcohol use, prior history of TB, and radiologically severe disease, while RAE-TB patients were older and had more comorbidities and combined extrapulmonary TB. A fluoroquinolone (FQ) was the drug most commonly added (70.5%, RMR-TB; 82.8%, RAE-TB). Median treatment duration was 453 days in RMR-TB and 371 days in RAE-TB (p = 0.001) and treatment success rates were 87.2% (34/39) and 80.0% (20/25), respectively (p = 0.586). Subanalysis of the RMR-TB group by treatment regimen (standard regimen [n = 11], standard regimen + FQ [n = 12], MDR-TB regimen [n = 21]) revealed a higher rate of radiologically severe disease in the MDR-TB subgroup, with similar treatment success rates for the subgroups (85.7% [6/7]), 91.7% [11/12], and 85.0% [17/20], respectively) despite different durations of treatment (345, 405, and 528 days, respectively). Two recurrences (33.3% [2/6]) developed only in standard regimen subgroup, suggesting that standard regimen is not enough to treat RMR-TB patients.. The treatment outcome of RMR-TB with 1

Topics: Adult; Age Distribution; Aged; Alcohol Drinking; Aminosalicylic Acid; Antitubercular Agents; Cohort Studies; Comorbidity; Cycloserine; Ethambutol; Female; Fluoroquinolones; HIV Infections; Humans; Isoniazid; Male; Middle Aged; Prothionamide; Pyrazinamide; Republic of Korea; Retrospective Studies; Rifampin; Severity of Illness Index; Treatment Outcome; Tuberculosis; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

The aim of this study was to describe the secular trends in drug-resistant tuberculosis (DR-TB) and to identify unique characteristics of multidrug-resistant tuberculosis (MDR-TB) in rural China.. A retrospective study was conducted using TB data collected from 36 TB prevention and control institutions serving rural populations in Shandong Province, China, for the period 2006-2015.. Approximately 8.3% of patients suffered from MDR-TB, among whom 70% were newly treated patients; this rate increased by 1.3% annually during the 10-year study period. An increase in the percentage of overall first-line drug resistance against isoniazid, rifampicin, ethambutol, and streptomycin was confirmed (p<0.05). The percentage of MDR-TB in new and previously treated cases increased at yearly rates of 9.9% and 11.1%, respectively. MDR-TB patients were more likely to be female (odds ratio (OR) 1.58, 95% confidence interval (CI) 1.32-1.89), smokers (OR 1.75, 95% CI 1.47-2.07), to have had recent TB contact (OR 1.58, 95% CI 1.04-2.42), or to have been retreated (OR 2.89, 95% CI 2.46-3.41).. Increasing MDR-TB and rates of primary MDR-TB characterize DR-TB cases in rural China. Persistent efforts need to be made among MDR-TB patients in future TB control strategies.

Topics: Adolescent; Adult; Aged; Antitubercular Agents; Child; Child, Preschool; China; Ethambutol; Female; Follow-Up Studies; Humans; Infant; Isoniazid; Logistic Models; Male; Middle Aged; Prevalence; Retrospective Studies; Rifampin; Rural Population; Streptomycin; Tuberculosis, Multidrug-Resistant; Young Adult

We evaluated the performance of two multiplex, real-time PCR tests (Anyplex II MTB/MDR and MTB/XDR; Seegene, Seoul, Korea), designed to detect the Mycobacterium tuberculosis complex (MTC) and drug-resistance mutations associated with isoniazid, rifampicin, fluoroquinolones, and second-line injectable drugs. We analyzed 122 clinical isolates with the Anyplex II MTB/MDR test, 68 of which were also tested with the Anyplex II MTB/XDR test. The Anyplex II MTB/MDR and MTB/XDR tests showed the following respective sensitivities and specificities: 68.8% and 100% for detecting isoniazid resistance, 93.8% and 100% for rifampicin, 82.8% and 100% for levofloxacin, 75.0% and 100% for kanamycin, and 92.6% and 100% for MTC identification. These kits correctly identified 61.8% of multi-drug resistant M. tuberculosis isolates and 64.7% of extensively drug-resistant M. tuberculosis isolates, and enabled semi-automatic detection of drug-resistant MTC in 3 hours. The Anyplex II kits could be useful as rule-in tests for detecting MTC and drug resistance.

Topics: Antitubercular Agents; DNA, Bacterial; Drug Resistance, Multiple, Bacterial; Extensively Drug-Resistant Tuberculosis; Fluoroquinolones; Humans; Isoniazid; Kanamycin; Levofloxacin; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Reagent Kits, Diagnostic; Real-Time Polymerase Chain Reaction; Rifampin; Sensitivity and Specificity; Seoul; Sequence Analysis, DNA; Tuberculosis, Multidrug-Resistant

A tertiary referral hospital in Bangkok, Thailand.. To evaluate the efficacy of a bronchoalveolar lavage fluid (BALF) tuberculosis (TB) polymerase chain reaction (PCR) assay for the diagnosis of sputum smear-negative pulmonary TB (PTB) and the usefulness of a drug-resistant (DR) TB-PCR assay compared with standard drug susceptibility testing (DST).. BALF samples from 918 patients with acid-fast bacilli (AFB) negative sputum smears who underwent bronchoscopy for diagnostic evaluations of pulmonary diseases were prospectively determined for specific genetic elements of TB using the AnyplexTM MTB/NTM Real-Time Detection kit. Positive TB-PCR samples were subsequently evaluated for DR-TB using the Anyplex II MTB/MDR Detection kit.. A total of 224 patients were finally diagnosed with PTB. The sensitivity, specificity, positive predictive value and negative predictive value of the TB-PCR assay were respectively 38.8%, 100%, 100%, and 83.5%. The TB-PCR assay was more sensitive than culture (30.4%) and smear (6.7%). Of the 68 TB-positive culture samples, three cases with either isoniazid (INH) or rifampicin (RMP) resistance were detected by DST. The Anyplex II MTB/MDR assay provided similar results.. The BALF TB-PCR assay is a useful tool in the diagnosis of sputum smear-negative PTB. It can also provide INH and RMP susceptibility patterns similar to those of standard DST.

Topics: Adult; Aged; Antitubercular Agents; Bronchoalveolar Lavage Fluid; Drug Resistance, Bacterial; Female; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Polymerase Chain Reaction; Predictive Value of Tests; Prospective Studies; Rifampin; Sensitivity and Specificity; Sputum; Tertiary Care Centers; Thailand; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Performance of the Xpert MTB/RIF assay, designed to simultaneously detect Mycobacterium tuberculosis complex (MTBC) and rifampin (RIF) resistance, has been well documented in low-resource settings with high TB-incidence. However, few studies have assessed its accuracy in low TB incidence settings. We evaluated the performance of Xpert MTB/RIF using clinical sputum specimens routinely collected from suspect pulmonary TB patients over a 4-year time period in San Diego County, California. Xpert MTB/RIF results were compared to acid-fast bacilli (AFB) smear microscopy, mycobacterial culture, and phenotypic drug susceptibility testing (DST). Of 751 sputum specimens, 134 (17.8%) were MTBC culture-positive and 2 (1.5%) were multidrug-resistant (MDR). For the detection of MTBC, Xpert MTB/RIF sensitivity was 89.6% (97.7% and 74.5% in smear-positive and -negative sputa, respectively) and specificity was 97.2%; while AFB smear sensitivity and specificity were 64.9% and 77.8%, respectively. Xpert MTB/RIF detected 35 of 47 smear-negative culture-positive specimens, and excluded 124 of 137 smear-positive culture-negative specimens. Xpert MTB/RIF also correctly excluded 99.2% (121/122) of nontuberculous mycobacteria (NTM) specimens, including all 33 NTM false-positives by smear microscopy. For the detection of RIF resistance, Xpert MTB/RIF sensitivity and specificity were 100% and 98.3%, respectively. Our findings demonstrate that Xpert MTB/RIF is able to accurately detect MTBC and RIF resistance in routinely collected respiratory specimens in a low TB-incidence setting, with comparable performance to that achieved in high-incidence settings; and suggest that under these conditions the assay has particular utility in detecting smear-negative TB cases, excluding smear-positive patients without MTBC disease, and differentiating MTBC from NTM.

Topics: Biological Assay; California; Drug Resistance, Microbial; Humans; Mycobacterium tuberculosis; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Topics: Antitubercular Agents; Humans; Isoniazid; Moldova; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Tuberculosis (TB) is considered as one of the most important infectious diseases in the world, and recent rise and spread of multidrug-resistant (MDR) Mycobacterium tuberculosis (MTB) strains, have made the matter worsened. Due to the importance of TB prevalence in Iran, this study was designed to investigate the genetic diversity among MDR strains of MTB by MIRU-VNTR typing scheme. A total of 88 drug resistant M. tuberculosis isolates belong to pulmonary TB cases were collected from several TB reference centers of Iran. Drug susceptibility testing for Isoniazid and Rifampin was performed using the agar proportion method and MDR isolates were underwent genotyping by using 12-locus- based MIRU-VNTR typing. On performing proportion method, 22 isolates were identified as MDR. By typing of MDR isolates using 12-loci MIRU-VNTR technique, high diversity were demonstrated in MDR strains and these were classified into 20 distinct MIRU-VNTR genotypes. MIRU loci 10 and 26 were the most discriminatory loci with 8 and 7 alleles respectively; while MIRU loci 2, 20, 24 and 39 were found to be the least discriminatory with 1-2 alleles each. We noticed a mixed infection in isolate 53, as this isolate comprised simultaneous two alleles in MIRU loci 40, 10, 16 and 39. In conclusion, this result represents MIRU-VNTR typing as a useful tool for studying genetic diversity of MDR-MTB in regional settings, and will help the health sectors to construct a preventive program for MDR-TB. Additionally, it can detect mixed infection which can facilitate management of treatment.

Topics: Alleles; Antitubercular Agents; DNA, Bacterial; Drug Resistance, Multiple, Bacterial; Genetic Loci; Humans; Iran; Isoniazid; Microbial Sensitivity Tests; Minisatellite Repeats; Multilocus Sequence Typing; Mycobacterium tuberculosis; Polymorphism, Genetic; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Tuberculosis is a major public health concern, and diagnostic strategies applied to animal populations are scarce. As part of ongoing efforts to control tuberculosis dissemination at our animal facility, two non-human primates (NHP, Saimiri sciureus) presenting cutaneous lesions were examined for mycobacterial infection. Both animals tested positive for acid-fast bacilli and Mycobacterium tuberculosis using a molecular assay (IS6110 PCR). Animals were euthanized and several samples were tested for M. tuberculosis using the Xpert MTB/RIF assay. Many samples were positive for M. tuberculosis and rifampicin resistance, and some produced mycobacterial growth. Oral swabs from cage mates were then tested with Xpert MTB/RIF, and the majority tested positive for M. tuberculosis and rifampicin resistance, and produced growth in culture. To our knowledge, this is the first report of multidrug-resistant mycobacterial infection in NHP. Additionally, our data shows that the Xpert MTB/RIF assay can be useful as a screening tool for tuberculosis infection in NHP.

Topics: Animals; Antitubercular Agents; Bacteriological Techniques; DNA, Bacterial; Drug Resistance, Multiple, Bacterial; Genotype; Monkey Diseases; Mycobacterium tuberculosis; Polymerase Chain Reaction; Predictive Value of Tests; Rifampin; Saimiri; Tuberculosis, Cutaneous; Tuberculosis, Multidrug-Resistant

China has a high burden of drug-resistant tuberculosis (TB). As irrational use and inadequate dosing of anti-TB drugs may contribute to the epidemic of drug-resistant TB, we assessed the drug types and dosages prescribed in the treatment of TB cases in a representative sample of health care facilities in Yunnan.. We applied multistage cluster sampling using probability proportion to size to select 28 counties in Yunnan. Consecutive pulmonary TB patients were enrolled from either the TB centers of Yunnan Center of Disease Control or designated TB hospitals. Outcomes of interest included the regimen used in the treatment of new and retreatment TB patients; and the proportion of patients treated with adequate dosing of anti-TB drugs. Furthermore, we assess whether there has been reduction in the use of fluoroquinolone and second line injectables in Tuberculosis Clinical Centre (TCC) after the training activity in late 2012.. Of 2390 TB patients enrolled, 582 (24.4%) were prescribed second line anti-TB drugs (18.0% in new cases and 60.9% in retreatment cases); 363(15.2%) prescribed a fluoroquinolone. General hospitals (adjusted odds ratio (adjOR) 1.97, 95% confidence interval (CI) 1.47-2.66), retreatment TB cases (adjOR 4.75, 95% CI 3.59-6.27), smear positive cases (adjOR 1.69, 95% CI 1.22-2.33), and extrapulmonary TB (adjOR 2.59, 95% CI 1.66-4.03) were significantly associated with the use of fluoroquinolones. The proportion of patients treated with fluoroquinolones decreased from 41.4% before 2013 to 13.5% after 2013 (adjOR 0.19, 95% CI 0.12-0.28) in TCC. The proportion of patients with correct, under and over dosages of isoniazid was 88.2%, 1.5%, and 10.4%, respectively; of rifampicin was 50.2%, 46.8%, and 2.9%; of pyrazinamide was 67.6%, 31.7% and 0.7%; and of ethambutol was 41.4%, 57.5%, and 1.0%.. The prescribing practice of anti-TB drugs was not standardized, findings with significant programmatic implication.

Topics: Adult; Aged; Antitubercular Agents; Asian People; China; Clinical Audit; Ethambutol; Female; Fluoroquinolones; Humans; Isoniazid; Male; Middle Aged; Outcome Assessment, Health Care; Prescriptions; Pyrazinamide; Retreatment; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Mycobacterium tuberculosis (MTB) is one of the most significant causes of mortality and morbidity. Early diagnose is important especially in multiple drug resistant tuberculosis to avoid transmission. Traditional techniques requires at least one to three weeks for diagnosis of tuberculosis. Diagnostic delays with multiple drug resistant tuberculosis are associated with worse clinical outcomes and increased transmission The Xpert MTB/RIF assay is one of the new diagnostic device for the diagnosis of tuberculosis and rapid detection of rifampicin resistance.. We assessed the performance of Xpert MTB/RIF assay for detecting rifampicin resistance using phenotypic drug susceptibility tests as automated BD MGIT 960.. Total of 2136 specimens were included in the study. Xpert MTB/RIF testing was performed on samples, using version 4 cartridges, according to the manufacturer's recommendations. The MTBC culture and first-line phenotypic DST were performed in automated BD MGIT 960 (Becton & Dickinson, USA) according to the recommendations of the manufacturer. Agar proportion was used in the case of inconsistency for rifampicin resistance.. Thirty-four samples (19 respiratory and 15 nonrespiratory samples) were determined as positive for M. tuberculosis complex by Xpert MTB/RIF (Cepheid GeneXpert® System, USA). Xpert MTB/RIF assay detected 4/34 (11.7%) specimens as rifampicin resistant. One of the rifampicin resistant isolates was determined susceptible in MGIT 960 automated system. This isolate was also tested with agar proportion method and found susceptible to rifampicin.. The Xpert MTB/RIF assay can be used as first-line assay for the detection of M. tuberculosis. However, microbiologists must be aware of the limitations of the assay.

Topics: Antibiotics, Antitubercular; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Phenotype; Reproducibility of Results; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Multidrug resistant (MDR) and extensively drug resistant tuberculosis (TB) are a threat to the TB control programs in developing countries, and the situation is worsened by the human immunodeficiency virus (HIV) pandemic. This study was performed to correlate treatment outcome with the resistance patterns in HIV-seropositive patients coinfected with pulmonary TB. Sputum specimens were collected from 1643 HIV-seropositive patients and subjected to microscopy and liquid culture for TB. The smear- and culture-positive Mycobacterium tuberculosis isolates were subjected to Genotype MTBDRplus assay version 2.0. The M. tuberculosis culture-positivity rate was 39.44% (648/1643) among the 1643 HIV-seropositive patients and the overall MDR-TB rate was 5.6% (36/648). There were 421 newly diagnosed and 227 previously treated patients, among whom, MDR-TB was associated with 2.9% and 10.57% cases, respectively. The rate of rifampicin monoresistant TB among the cases of MDR-TB was 2.31% (15/648) and the rate of combined rifampicin and isoniazid resistance was 3.24% (21/648). The cure and death rates among the 20 registered cases were 30% (6/20) and 35% (7/20), respectively. Five cases were on treatment and two cases were defaulters among the 20 registered cases. High death rate (13, 36.1%, 95% confidence interval 20.8-53.8) was observed in this study among the patients who had mutations at the 530-533 codons. The present study emphasized the prerequisite to monitor the trend of drug-resistant TB in various mutant populations in order to timely implement appropriate interventions to curb the threat of MDR-TB.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antitubercular Agents; Child; Child, Preschool; Female; HIV Infections; Humans; Infant; Infant, Newborn; Male; Middle Aged; Mycobacterium tuberculosis; Prevalence; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

While tuberculosis incidence and mortality are declining in South Africa, meeting the goals of the End TB Strategy requires an invigorated programmatic response informed by accurate data. Enumerating the losses at each step in the care cascade enables appropriate targeting of interventions and resources.. We estimated the tuberculosis burden; the number and proportion of individuals with tuberculosis who accessed tests, had tuberculosis diagnosed, initiated treatment, and successfully completed treatment for all tuberculosis cases, for those with drug-susceptible tuberculosis (including human immunodeficiency virus (HIV)-coinfected cases) and rifampicin-resistant tuberculosis. Estimates were derived from national electronic tuberculosis register data, laboratory data, and published studies.. The overall tuberculosis burden was estimated to be 532005 cases (range, 333760-764480 cases), with successful completion of treatment in 53% of cases. Losses occurred at multiple steps: 5% at test access, 13% at diagnosis, 12% at treatment initiation, and 17% at successful treatment completion. Overall losses were similar among all drug-susceptible cases and those with HIV coinfection (54% and 52%, respectively, successfully completed treatment). Losses were substantially higher among rifampicin- resistant cases, with only 22% successfully completing treatment.. Although the vast majority of individuals with tuberculosis engaged the public health system, just over half were successfully treated. Urgent efforts are required to improve implementation of existing policies and protocols to close gaps in tuberculosis diagnosis, treatment initiation, and successful treatment completion.

Topics: Antibiotics, Antitubercular; Antitubercular Agents; Black People; Coinfection; Community Health Services; Cost of Illness; Disease Eradication; Drug Resistance, Multiple, Bacterial; HIV Infections; Humans; Incidence; Lost to Follow-Up; Mycobacterium tuberculosis; Patient Care; Rifampin; South Africa; Treatment Outcome; Tuberculosis; Tuberculosis, Multidrug-Resistant

Topics: Antibiotics, Antitubercular; Antitubercular Agents; Humans; Mycobacterium tuberculosis; Rifabutin; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

The discrepancy rates of drug susceptibility testing (DST) results between solid and liquid media have been reported to range from 2.4 to 7.4% for isoniazid. Most isolate with isoniazid DST discrepancies between solid and liquid media test as susceptible on solid medium and resistant in liquid medium, however, the optimal management of patients with discordant testing is unknown. This study was conducted to evaluate the effect of treatment regimen on treatment outcomes when patients with rifampicin-susceptible pulmonary tuberculosis have isoniazid resistance (INH-R) in liquid medium but isoniazid susceptibility (INH-S) on solid medium.. This study was retrospectively conducted by reviewing patient medical records on the liquid compared to solid culture based phenotypic testing at Samsung Medical Center between January 2009 and December 2015. The study population which have INH-R in liquid medium and INH-S on solid medium was divided into two groups: group A (n = 30), which included patients treated for INH-S tuberculosis by discontinuing pyrazinamide (and ethambutol), and group B (n = 56), which included patients treated for INH-R tuberculosis by continuing pyrazinamide and/or adding fluoroquinolone. Unfavorable outcomes included treatment failure and relapse.. There were no statistically significant differences between the two groups including demographic data, comorbidities, radiologic data, and treatment duration. However, baseline smear positive rates were more frequent in group A (19/30, 63.3%) than in group B (22/56, 39.3%; P = 0.033). Only three patients had unfavorable outcomes; one was bacteriologically proven treatment failure and the other two were clinically judged as unfavorable outcomes. All of them were in the group A (3/30, 10%); no unfavorable outcomes occurred in the group B (0/56, 0%; P = 0.040).. Unfavorable outcomes were less frequent in the group B than in the group A, indicating that treatment regimen modification according to DST results on liquid medium could improve treatment outcomes in patients with rifampicin-susceptible pulmonary tuberculosis. Further studies are required to confirm these findings to overcome the small number of unfavorable outcomes.

Topics: Aged; Antitubercular Agents; Drug Resistance, Bacterial; Drug Therapy, Combination; Ethambutol; Female; Fluoroquinolones; Humans; Isoniazid; Male; Middle Aged; Mycobacterium tuberculosis; Nucleic Acid Synthesis Inhibitors; Pyrazinamide; Republic of Korea; Retrospective Studies; Rifampin; Treatment Failure; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Multidrug-resistant tuberculosis (MDR-TB) case finding progressively increased in Ethiopia mainly as a result of the utilization of World Health Organization (WHO)-endorsed rapid technologies including MTBDRplus assay. However, there is inadequate data on routine testing performance of the MTBDRplus assay. Consequently, the aim of the study was to assess the routine performance of the MTBDRplus assay in detecting MDR-TB at St. Peter's TB Specialized Hospital.. The sensitivity and specificity of MTBDRplus in detecting isoniazid (INH) resistance were 96.3 and 100%, respectively. While for rifampicin (RIF) 100% was recorded for both. Similarly, a sensitivity of 97.96% and a specificity of 100% was measured for detecting MDR-TB. Among 49 MTBDRplus RIF resistant isolates, 46 (93.9%) strains had rpoB mutation. S531L was the most common rpoB mutant (81.6% of RIF resistant cases). All MTBDRplus INH resistant isolates (n = 52) had S315T1 katG mutation.

Topics: Antitubercular Agents; Biological Assay; Drug Resistance, Bacterial; Ethiopia; Hospitals; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

Europe has the highest documented caseload and greatest increase in multidrug and extensively drug-resistant tuberculosis (M/XDR-TB) of all World Health Organization (WHO) regions. This survey examines how recommendations for M/XDR-TB management are being implemented.. TBNET is a pan-European clinical research collaboration for tuberculosis. An email survey of TBNET members collected data in relation to infection control, access to molecular tests and basic microbiology with drug sensitivity testing.. 68/105 responses gave valid information and were from countries within the WHO European Region. Inpatient beds matched demand, but single rooms with negative pressure were only available in low incidence countries; ultraviolet decontamination was used in 5 sites, all with >10 patients with M/XDR-TB per year. Molecular tests for mutations associated with rifampicin resistance were widely available (88%), even in lower income and especially in high incidence countries. Molecular tests for other first line and second line drugs were less accessible (76 and 52% respectively). A third of physicians considered that drug susceptibility results were delayed by > 2 months.. Infection control for inpatients with M/XDR-TB remains a problem in high incidence countries. Rifampicin resistance is readily detected, but tests to plan regimens tailored to the drug susceptibilities of the strain of Mycobacterium tuberculosis are significantly delayed, allowing for further drug resistance to develop.

Topics: Antitubercular Agents; Decontamination; Developing Countries; Drug Resistance, Bacterial; Europe; Extensively Drug-Resistant Tuberculosis; Humans; Infection Control; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Patient Isolation; Rifampin; Surveys and Questionnaires; Tuberculosis, Multidrug-Resistant; Ultraviolet Rays

Djibouti is a small country in the Horn of Africa with a high TB incidence (378/100,000 in 2015). Multidrug-resistant TB (MDR-TB) and resistance to second-line agents have been previously identified in the country but the extent of the problem has yet to be quantified. A national survey was conducted to estimate the proportion of MDR-TB among a representative sample of TB patients. Sputum was tested using XpertMTB/RIF and samples positive for MTB and resistant to rifampicin underwent first line phenotypic susceptibility testing. The TB supranational reference laboratory in Milan, Italy, undertook external quality assurance, genotypic testing based on whole genome and targeted-deep sequencing and phylogenetic studies. 301 new and 66 previously treated TB cases were enrolled. MDR-TB was detected in 34 patients: 4.7% of new and 31% of previously treated cases. Resistance to pyrazinamide, aminoglycosides and capreomycin was detected in 68%, 18% and 29% of MDR-TB strains respectively, while resistance to fluoroquinolones was not detected. Cluster analysis identified transmission of MDR-TB as a critical factor fostering drug resistance in the country. Levels of MDR-TB in Djibouti are among the highest on the African continent. High prevalence of resistance to pyrazinamide and second-line injectable agents have important implications for treatment regimens.

Topics: Adolescent; Adult; Africa; Aged; Antitubercular Agents; Child; Child, Preschool; Djibouti; Female; Fluoroquinolones; High-Throughput Nucleotide Sequencing; Humans; Infant; Infant, Newborn; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Phylogeny; Prevalence; Rifampin; Surveys and Questionnaires; Tuberculosis, Multidrug-Resistant; Young Adult

Drug resistance surveillance is crucial for control of drug-resistant tuberculosis (TB). However, limited data exists on the burden of drug-resistant TB in children. The goal of this work was to generate prevalence data regarding rifampicin- (RIF-) resistant childhood TB in northern China and to test the feasibility of Xpert for surveying pediatric TB drug resistance prevalence. We enrolled 362 clinically diagnosed childhood TB patients and collected sputum, gastric lavage aspirate (GLA), bronchoalveolar lavage fluid (BALF), and cerebral spinal fluid (CSF) samples. Xpert and solid culture were utilized to detect RIF resistance. The detection rate of Xpert-positive TB among new clinically diagnosed TB cases was 38.4% (139/362), significantly higher than that of solid culture-positive TB (16.3%, 59/362,

Topics: Adolescent; Anti-Bacterial Agents; Child; Child, Preschool; China; Drug Resistance, Bacterial; Feasibility Studies; Female; Humans; Infant; Male; Molecular Diagnostic Techniques; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Public Health Surveillance; Rifampin; Tuberculosis, Multidrug-Resistant

To investigate the application value of Xpert MTB/RIF in diagnosis of spinal tuberculosis and detection of rifampin resistance.. The 109 pus specimens were obtained from patients who were primaryly diagnosed as spinal tuberculosis. All of the pus specimens were detected by acid-fast stain, liquid fast culturing by BACTEC MGIT 960 and Xpert MTB/RIF assay to definite the differences in sensitivity and specificity of mycobacterium tuberculosis among detecting methods. Pus specimens obtained by different methods were deteceded by MTB/RIF test to analyze the self-influence on Xpert MTB/RIF test. The result of liquid fast culturing by BACTEC MGIT 960 was used as the gold standard; and the value of Xpert MTB/RIF assay in detecting rifampin resistance was analyzed.. The sensitivity of acid-fast stain, liquid fast culturing by BACTEC MGIT 960 and Xpert MTB/RIF assay were 25.92%, 48.15%, 77.78%, respectively. The sensitivity of pus specimens obtained from open surgery, ultrasound positioning puncture and biopsy the sensitivity were 83.78%, 76.47%, 44.68% respectively deteceded by MTB/RIF test. According to the gold standard of the results of liquid fast culturing by BACTEC MGIT 960 assay, the sensitivity and specificity of Xpert MTB/RIF assay in detecting rifampin resistance were 80%(4/5) and 90.70%(39/43), respectively.. Xpert MTB/RIF assay has higher value in diagnosis of spinal tuberculosi, and also can detect rifampin resistance. The number of mycobacterium tuberculosis in pus specimens has a great influence in the sensitivity of Xpert MTB/RIF assay.

Topics: Antibiotics, Antitubercular; Humans; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Staining and Labeling; Suppuration; Tuberculosis, Multidrug-Resistant; Tuberculosis, Spinal

The spread of multidrug resistant Mycobacterium tuberculosis is one of the major challenges in tuberculosis control. In Eurasia, the spread of multidrug resistant tuberculosis is driven by the M. tuberculosis Beijing genotype. In this study, we examined whether selective advantages are present in the proteome of Beijing isolates that contribute to the emergence of this genotype. To this end, we compared the proteome of M. tuberculosis Beijing to that of M. tuberculosis H37Rv, both in the presence and absence of the first-line antibiotic rifampicin. During rifampicin exposure, both M. tuberculosis genotypes express proteins belonging to the DosR dormancy regulon, which induces a metabolically hypoactive-, drug tolerant phenotype. However, these markers of rifampicin tolerance were already more abundant in the M. tuberculosis Beijing isolate prior to drug exposure. To determine whether the a priori high abundance of specific proteins contribute to the formation of antibiotic resistance in M. tuberculosis Beijing, we quantified the abundance of 33 selected proteins in 27 clinical isolates from the five most common M. tuberculosis lineages using parallel reaction monitoring. The observed pre-existing high abundance of dormancy proteins in Beijing strains provides an evolutionary advantage that allows these strains to persist for prolonged periods during rifampicin treatment.. M. tuberculosis is the leading cause of death by a bacterial infection worldwide. Treatment-regimen to eradicate this pathogen make use of the first-line antibiotic rifampicin, which is considered to be the cornerstone of modern day anti-tuberculosis treatment. Despite the potency of rifampicin, there is an increasing occurrence of rifampicin resistant mutants in a specific cluster of M. tuberculosis, the Beijing genotype. Using both a data dependent acquisition and a targeted proteomic approach we identified markers of rifampicin tolerance to be high abundant in members of the M. tuberculosis Beijing genotype, already prior drug exposure. The identification of this M. tuberculosis Beijing specific trait will contribute to improved diagnostics and treatment of M. tuberculosis.

Topics: Bacterial Typing Techniques; Biomarkers, Pharmacological; China; Communicable Diseases, Emerging; Drug Resistance, Multiple, Bacterial; Epidemiological Monitoring; Humans; Molecular Diagnostic Techniques; Mycobacterium tuberculosis; Proteomics; Rifampin; Tuberculosis, Multidrug-Resistant

The diagnosis of smear-negative pulmonary tuberculosis (PTB) is particularly challenging, and automated liquid culture and molecular line probe assays (LPA) may prove particularly useful. The objective of our study was to evaluate the diagnostic potential of automated liquid culture (ALC) technology and commercial LPA in sputum smear-negative PTB suspects. Spot sputum samples were collected from 145 chest-symptomatic smear-negative patients and subjected to ALC, direct drug susceptibility test (DST) testing and LPA, as per manufacturers' instructions. A diagnostic yield of 26.2% was observed among sputum smear-negative TB suspects with 47.4% of the culture isolates being either INH- and/or rifampicin-resistant. Complete agreement was observed between the results of ALC assay and LPA except for two isolates which demonstrated sensitivity to INH and rifampicin at direct DST but were rifampicin-resistant in LPA. Two novel mutations were also detected among the multidrug isolates by LPA. In view of the diagnostic challenges associated with the diagnosis of TB in sputum smear-negative patients, our study demonstrates the applicability of ALC and LPA in establishing diagnostic evidence of TB.

Topics: Adult; Bacteriological Techniques; Bronchoalveolar Lavage Fluid; Drug Resistance, Multiple; Female; Humans; Male; Middle Aged; Molecular Probe Techniques; Mutation; Mycobacterium tuberculosis; Pleura; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

The pattern of Mycobacterium tuberculosis susceptibility to first line drugs and multidrug resistance in Al-Madinah Al-Munawarah, a seasonally overcrowded are during Hajj and Omrah, is not well studied.. This study aimed to investigate anti-tuberculosis drug resistance and its distribution among new cases in Al-Madinah Al-Monawarah.. Study subjects included 622 patients with first time confirmed TB referred to the central tuberculosis laboratory in Al-Madinah between January 2012 and December 2014.. Out of the 622 isolates, 99 (15.9%) were Mycobacteria Other Than Tuberculosis (MOTTS) and 25 (4.0%), three of which (12%) were children under five years of age, revealed multidrug resistance (MDR). Monoresistance to isoniazid (H) was (1.8%), to rifampin (R) was (1.4%), to streptomycin (S) was (1.9 %) to ethambutol (E) was (1.1 %) and to pyrazinamide (Z) was (2.1%).. Being among the new cases, multidrug resistant tuberculosis (MDR TB) is supposed to be caused by strains which are originally multidrug resistant. Neither nationality nor gender was found to be associated with MDR TB. Since 12% of MDR cases were among children, a probability of primary infection with MDR strains is to be considered. Moreover, mass gathering during Hajj and Omrah seasons does not seem to increase the burden of MDR in the region. However, further investigation is needed to molecularly characterize MDR isolates and their phylogenetics and geographical origin.

Topics: Adolescent; Adult; Antitubercular Agents; Child; Cost of Illness; Female; Humans; Islam; Isoniazid; Male; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Phylogeny; Rifampin; Saudi Arabia; Streptomycin; Travel; Tuberculosis, Multidrug-Resistant; Young Adult

Topics: Antitubercular Agents; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

To characterize rifampicin-resistant strains missed by the Mycobacteria Growth Indicator Tube (MGIT) 960 system but not by egg-based media in the UK and Ireland and to ascertain their prevalence.. All strains sent for second-line susceptibility testing were prospectively collected. Drug Susceptibility Testing was performed by Resistance Ratio (RR), Proportion Method (PM), MGIT 960 and MIC determination by microdilution. Rifampicin-resistance-conferring mutations were detected with line probe assays and sequencing. At the end of the study period, retrospective archived strains from 2010 to 2014 showing key mutations were analysed phenotypically and genotypically.. Seventeen of 7234 prospective isolates were included. All of them were susceptible by MGIT. One was borderline by RR (MIC to rifampicin of 4 mg/L) and was resistant by PM. Eight were resistant and eight were highly resistant on RR. These 16 isolates had MICs between 1 and 8 mg/L on microdilution. With PM, 16/17 were susceptible to rifampicin. 17/17 had mutations in the rpoB gene. D516Y was the mutation most frequently found (13/17). Retrospectively, ten additional strains with key genotypes were found in our collection: 6/10 were susceptible in the MGIT and resistant in RR. Of the 27 studied strains, the MGIT only detected resistance in four.. Rifampicin resistance is missed by the MGIT system. In the UK and Ireland the prevalence of these strains is low. The introduction of routine molecular testing would detect false susceptibility. Further research is needed to ascertain the role of these strains in clinical failure and their prevalence in other settings.

Topics: Antitubercular Agents; Drug Resistance, Bacterial; Genotype; Humans; Ireland; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Phenotype; Population Surveillance; Prevalence; Rifampin; Tuberculosis, Multidrug-Resistant; United Kingdom

Xpert MTB/RIF is an automated nucleic acid amplification test (NAT) that can detect the presence of Mycobacterium tuberculosis complex (MTC) in clinical specimens as well as rifampicin (RIF) resistance resulting from rpoB mutation. Despite its high sensitivity and specificity for diagnosing tuberculosis (TB) with or without RIF resistance, the clinical performance of the test is variable. In this study, we evaluated the performance of Xpert MTB/RIF in a setting of moderate TB burden and high medical resources. A total of 427 sputum specimens were obtained from 237 suspected TB cases. Of these, 159 were identified as active TB, while the other 78 were non-TB diseases. The overall sensitivity and specificity of MTC detection by Xpert MTB/RIF using culture results as a reference were 86.8% [95% confidence interval (CI): 81.8%-90.6%] and 96.8% (95% CI: 93.1%-98.5%), respectively. Among MTC-positive culture specimens, Xpert MTB/RIF positivity was 95.2% (95% CI: 91.2%-97.5%) in smear-positive and 44.7% (95% CI 30.1-60.3) in smear-negative specimens. Xpert MTB/RIF was similar to other NATs (TaqMan MTB and TRCRapid M.TB) in terms of performance. Xpert MTB/RIF detected 25 RIF-resistant isolates as compared to 22 with the mycobacterial growth indicator tube antimicrobial susceptibility testing system, yielding a sensitivity of 100% (95% CI: 85.1%-100%) and specificity of 98.3% (95% CI: 95.1%-99.4%). These results indicate that although sensitivity in smear-negative/culture-positive specimens was relatively low, Xpert MTB/RIF is a useful diagnostic tool for detecting TB and RIF resistance even in settings of moderate TB burden.

Topics: Adult; Aged; Aged, 80 and over; Antibiotics, Antitubercular; Female; Humans; Incidence; Male; Middle Aged; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Prospective Studies; Rifampin; ROC Curve; Sensitivity and Specificity; Sputum; Statistics, Nonparametric; Tuberculosis, Multidrug-Resistant; Young Adult

We investigated discrepant results determined using the Genotype. Among 1373 MTBDRplus assays performed at our tertiary referral center in South Korea between August 2009 and December 2015, the results for 46 (3.4%) differed from those for ADST. KatG and inhA gene sequencing analysis results were available for 23 patients. ADSTs were carried out using the absolute concentration method with Löwenstein-Jensen media.. Results from 11 patients indicated INH susceptibility by MTBDRplus assay and INH resistance by ADST. For 5 of these patients, sequencing revealed no evidence of mutations, whereas specific mutations were detected in the remaining 6 patients. These should have been detected using the MTBDRplus assay. The other 12 patients had isolates with the opposite discrepancy, that is INH resistance by MTBDRplus assay but INH susceptibility by ADST. For 7 of these cases, sequencing results were consistent with those of the MTBDRplus assay. However, sequencing analysis did not explain the discrepancies in the remaining 5 patients. All 23 patients with discrepant results received individualized treatment regimens determined by the attending physician according to their test results and susceptibility to other drugs, such as rifampin. Good outcomes were reported for the majority.. Discrepancies between test results for INH resistance on the MTBDRplus assay and ADST appear to be infrequent. Gene sequencing analysis is useful for identifying the cause of the discrepancy.

Topics: Adult; Aged; Antitubercular Agents; Bacterial Proteins; Catalase; Female; Genotype; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Oxidoreductases; Republic of Korea; Retrospective Studies; Rifampin; Sequence Analysis, DNA; Treatment Outcome; Tuberculosis; Tuberculosis, Multidrug-Resistant

Resistance-associated variants (RAVs) in Rv0678 , a regulator of the MmpS5-MmpL5 efflux pump, have been shown to lead to increased MICs of bedaquiline (2- to 8- fold) and clofazimine (2- to 4-fold). The prevalence of these Rv0678 RAVs in clinical isolates and their impact on treatment outcomes are important factors to take into account in bedaquiline treatment guidelines.. Baseline isolates from two bedaquiline MDR-TB clinical trials were sequenced for Rv0678 RAVs and corresponding bedaquiline MICs were determined on 7H11 agar. Rv0678 RAVs were also investigated in non-MDR-TB sequences of a population-based cohort.. Rv0678 RAVs were identified in 23/347 (6.3%) of MDR-TB baseline isolates. Surprisingly, bedaquiline MICs for these isolates were high (> 0.24 mg/L, n  =   8), normal (0.03-0.24 mg/L, n  =   11) or low (< 0.03 mg/L, n  =   4). A variant at position -11 in the intergenic region mmpS5 - Rv0678 was identified in 39 isolates (11.3%) and appeared to increase the susceptibility to bedaquiline. In non-MDR-TB isolates, the frequency of Rv0678 RAVs was lower (6/852 or 0.7%). Competition experiments suggested that rifampicin was not the drug selecting for Rv0678 RAVs.. RAVs in Rv0678 occur more frequently in MDR-TB patients than previously anticipated, are not associated with prior use of bedaquiline or clofazimine, and in the majority of cases do not lead to bedaquiline MICs above the provisional breakpoint (0.24 mg/L). Their origin remains unknown. Given the variety of RAVs in Rv0678 and their variable effects on the MIC, only phenotypic drug-susceptibility methods can currently be used to assess bedaquiline susceptibility.

Topics: Anti-Inflammatory Agents; Antibiotics, Antitubercular; Antitubercular Agents; Clinical Trials as Topic; Clofazimine; Diarylquinolines; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Prevalence; Rifampin; Sequence Analysis, DNA; Tuberculosis, Multidrug-Resistant

Prevailing data on rifampicin-resistant M. tuberculosis is essential for early management of MDR-TB. Therefore, this study was conducted to determine the prevalence of rifampicin-resistant Mycobacterium tuberculosis and associated factors among presumptive TB cases in Debre Markos Referral Hospital, Ethiopia.. A cross-sectional study was conducted from September 2014 to March 2015. Detection of M. tuberculosis and resistance to rifampicin was performed using Gene Xpert MTB/RIF assay. Data was collected using structured questionnaire by face to face interview. Logistic regression analysis was computed to determine the associated factors of rifampicin-resistant M. tuberculosis.. A total of 505 presumptive TB patients included in the study. The prevalence of M. tuberculosis confirmed cases was 117 (23.2%) (95% CI 19.7-27%). It was higher among males (27.9%) than females (17.9%) (AOR: 2.17; CI 1.35-3.49). Of the 117 M. tuberculosis confirmed cases, 12 (10.3%) (95% CI 6.0-17.1%) were resistant to rifampicin. Rifampicin-resistant M. tuberculosis was noticed in 7 previously treated TB patients (17.1%) and 5 treatment naive patients (6.7%) (AOR: 4.16; CI 1.04-16.63). The prevalence of rifampicin-resistant M. tuberculosis was 6 (9.8%) and 6 (11.3%) in pulmonary and extra-pulmonary infections, respectively. Of the 30, MTB/HIV co-infection, 3 (10%) were rifampicin-resistant M. tuberculosis.. Rifampicin-resistant M. tuberculosis is prevalent in both pulmonary and extra-pulmonary tuberculosis patients. Previous treatment with anti-TB drugs was significantly associated with rifampicin resistance. Therefore, the use of Gene Xpert should be scaled up across the country for rapid detection and management of drug resistant M. tuberculosis.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Child; Cross-Sectional Studies; Drug Resistance, Bacterial; Ethiopia; Female; Humans; Male; Middle Aged; Mycobacterium tuberculosis; Prevalence; Regression Analysis; Rifampin; Sample Size; Surveys and Questionnaires; Tuberculosis; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

Globally 3.9% of new and 21% of re-treatment tuberculosis (TB) cases are multidrug-resistant or rifampicin-resistant (MDR/RR), which is often interpreted as evidence that drug resistance results mainly from poor treatment adherence. This study aims to assess the respective contributions of the different causal pathways leading to MDR/RR-TB at re-treatment.. We use a simple mathematical model to simulate progression between the different stages of disease and treatment for patients diagnosed with TB. The model is parameterised using region and country-specific TB disease burden data reported by the World Health Organization (WHO). The contributions of four separate causal pathways to MDR/RR-TB among re-treatment cases are estimated: I) initial drug-susceptible TB with resistance amplification during treatment; II) initial MDR/RR-TB inappropriately treated as drug-susceptible TB; III) MDR/RR-TB relapse despite appropriate treatment; and IV) re-infection with MDR/RR-TB.. At the global level, Pathways I, II, III and IV contribute 38% (28-49, 95% Simulation Interval), 44% (36-52, 95% SI), 6% (5-7, 95% SI) and 12% (7-19, 95% SI) respectively to the burden of MDR/RR-TB among re-treatment cases. Pathway II is dominant in the Western Pacific (74%; 67-80 95% SI), Eastern Mediterranean (68%; 60-74 95% SI) and European (53%; 48-59 95% SI) regions, while Pathway I makes the greatest contribution in the American (53%; 40-66 95% SI), African (43%; 28-61 95% SI) and South-East Asian (50%; 40-59 95% SI) regions.. Globally, failure to diagnose MDR/RR-TB at first presentation is the leading cause of the high proportion of MDR/RR-TB among re-treatment cases. These findings highlight the need for contextualised solutions to limit the impact and spread of MDR/RR-TB.

Topics: Antitubercular Agents; Humans; Models, Statistical; Retreatment; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; World Health Organization

Topics: Adult; Antitubercular Agents; Communicable Disease Control; Drug Resistance, Bacterial; Equatorial Guinea; Female; Geography; HIV Seropositivity; Humans; Infectious Disease Medicine; Male; Mycobacterium tuberculosis; Recurrence; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Young Adult

Multidrug-resistant tuberculosis (MDR-TB), caused by drug-resistant strains of Mycobacterium tuberculosis, is an increasingly serious problem worldwide. Here we examined a data set of whole-genome sequences from 5,310 M. tuberculosis isolates from five continents. Despite the great diversity of these isolates with respect to geographical point of isolation, genetic background and drug resistance, the patterns for the emergence of drug resistance were conserved globally. We have identified harbinger mutations that often precede multidrug resistance. In particular, the katG mutation encoding p.Ser315Thr, which confers resistance to isoniazid, overwhelmingly arose before mutations that conferred rifampicin resistance across all of the lineages, geographical regions and time periods. Therefore, molecular diagnostics that include markers for rifampicin resistance alone will be insufficient to identify pre-MDR strains. Incorporating knowledge of polymorphisms that occur before the emergence of multidrug resistance, particularly katG p.Ser315Thr, into molecular diagnostics should enable targeted treatment of patients with pre-MDR-TB to prevent further development of MDR-TB.

Topics: Antitubercular Agents; Bacterial Proteins; Catalase; Drug Resistance, Multiple, Bacterial; Genomics; Humans; Isoniazid; Mutation; Mycobacterium tuberculosis; Polymorphism, Genetic; Rifampin; Tuberculosis, Multidrug-Resistant

In Mali early detection and treatment of multidrug-resistant tuberculosis (MDR-TB) are still challenging due to the cost, time and/or complexity associated with regular tests. Microscopic Observation Drug Susceptibility (MODS) is a low-cost assay validated by WHO in 2010. It is a liquid-culture-based assay to detect the 'cording' characteristic of Mycobacterium tuberculosis complex and to assess susceptibility to both isoniazid and rifampicin defining multidrug-resistant tuberculosis (MDR-TB). In this study we aimed to evaluate the performance of MODS as diagnostic tool compared with a validated method-Mycobacteria Growth Indicator Tube/Antimicrobial Susceptibility Testing/Streptomycin, Isoniazid, Rifampicin and Ethambutol (MGIT/AST/SIRE).. Between January 2010 and October 2015 we included 98 patients with suspected TB in an observational cohort study. The sensitivity and specificity of MODS assay for detecting TB were respectively 94.12% and 85.71% compared with the reference MGIT/7H11 culture, with a Cohen κ coefficient of 0.78 (95% CI 0.517-1.043). The median time to culture positivity for MODS assay and MGIT (plus interquartile range, IQR) was respectively 8 days (IQR 5-11) and 6 days (IQR 5-6). In detecting patients with MDR-TB, the sensitivity and specificity of MODS assay were respectively 100% and 95.92%. The positive predictive value and negative predictive value were, respectively, 66.7% and 100%. The median turnaround times for obtaining MDR-TB results using MODS assay and MGIT/AST/SIRE was respectively 9 days and 35 days. Hence, the MODS assay rapidly identifies MDR-TB in Mali compared with the MGIT/AST/SIRE.. As an easy, simple, fast and affordable method, the MODS assay could significantly improve the management of TB.

Topics: Adolescent; Adult; Antitubercular Agents; Cohort Studies; Early Diagnosis; Ethambutol; Female; Humans; Isoniazid; Male; Mali; Microbial Sensitivity Tests; Microscopy; Middle Aged; Mycobacterium tuberculosis; Prospective Studies; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant; Young Adult

Tuberculosis (TB) remains one of the world's deadliest communicable diseases. In Ethiopia, tuberculosis patients have different pattern of health care seeking behavior. They usually adopt other approaches like traditional healers and spiritual holy water sites before consulting public health facilities. This study was aimed to assess the prevalence of smear positive pulmonary tuberculosis and associated risk factors among tuberculosis suspects attending spiritual holy water sites.. A cross-sectional study was conducted from February 01, 2015 to March 30, 2015 in seven selected holy water sites in Northwest Ethiopia. During the study period, a total of 1384 adult holy water users were screened for PTB symptoms. A total of 382 pulmonary tuberculosis suspects participated in the study. Socio-demographic data were collected using a semi-structured questionnaire. Spot-morning-spot sputum specimens were collected and examined for acid fast bacilli using Auramine O fluorescence staining technique. Smear positive sputum samples were tested by GeneXpert MTB/RIF assay for rifampicin resistance. Descriptive statistics, binary and multivariate logistic regression analysis were employed using SPSS-16 software.. The prevalence of smear positive pulmonary tuberculosis was 2.9% with point prevalence of 795/100, 000 holy water users. History of contact with tuberculosis patient (AOR = 9.174, 95% C.I = 2.195-38.34) and the number of family members > 5 per household (AOR = 9.258, 95% C.I = 1.14-74.97) were significantly associated with smear positive pulmonary tuberculosis. Rifampicin resistance was not detected from all smear positives by GeneXpert MTB/RIF assay.. The prevalence of smear positive pulmonary tuberculosis in spiritual holy water sites was 7.4 fold higher than the general population. History of contact with active tuberculosis patients and increased family size were significantly associated with smear positive pulmonary TB. The national tuberculosis program should consider spiritual holy water sites as potential foci for TB transmission and plan regular survey and health education in holy water sites for effective TB prevention and control in the country.

Topics: Adolescent; Adult; Antitubercular Agents; Cross-Sectional Studies; Ethiopia; Family Characteristics; Female; Humans; Male; Middle Aged; Mycobacterium tuberculosis; Prevalence; Religion; Rifampin; Risk Factors; Sputum; Travel; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

Topics: Antitubercular Agents; Humans; Isoniazid; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Xpert MTB/RIF (Xpert) detects rifampicin-resistant tuberculosis (RR-tuberculosis), enabling physicians to rapidly initiate a World Health Organization-recommended 5-drug regimen while awaiting second-line drug-susceptibility test (DST) results. We quantified the second-line DST results time and proportion of patients potentially placed on suboptimal therapy.. We included RR-tuberculosis patients detected using Xpert at the South African National Health Laboratory Services (NHLS) of the Western Cape between November 2011 and June 2013 and at Eastern Cape, Free State, and Gauteng NHLS between November 2012 and December 2013. We calculated time from specimen collection to phenotypic second-line DST results. We identified isoniazid and ethionamide resistance mutations on line probe assay and performed pyrazinamide sequencing.. Among 1332 RR-tuberculosis patients, only 44.7% (596) had second-line DST for both fluoroquinolones and second-line injectable: 55.8% (466 of 835) in the Western Cape and 26.2% (130 of 497) in the other provinces. Patients with smear negative disease and age ≤10 years were less likely to have a result (risk ratio [RR] = 0.72; 95% CI, 0.64-0.81 and RR = 0.49; 95% CI, 0.26-0.79). Median time to second-line DST was 53 days (range, 8-259). Of the 252 patients with complete second-line DST, 101 (40.1%) potentially initiated a suboptimal regimen: 46.8% in the Western Cape and 25.3% in the other provinces.. Many South Africans diagnosed with RR-tuberculosis by Xpert initiate a suboptimal regimen, with information to adjust therapy available in half of all patients after a median 7 weeks. Algorithm completion and time delays remain challenging.

Topics: Adult; Drug Resistance, Bacterial; Ethionamide; Female; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Molecular Diagnostic Techniques; Mutation; Mycobacterium tuberculosis; Reagent Kits, Diagnostic; Rifampin; South Africa; Sputum; Tuberculosis, Multidrug-Resistant; Young Adult

Topics: Antibiotics, Antitubercular; Clinical Trials as Topic; Humans; Mycobacterium tuberculosis; Real-Time Polymerase Chain Reaction; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

In July 2012, the United States Agency for International Development (USAID) Quality Health Care Project introduced the Xpert® MTB/RIF assay at the facility level of the primary health care system in Kyrgyzstan. This study analysed the results of the implementation of Xpert.. Test results from 2734 patients from July 2012 to December 2014 were analysed. The sensitivity and specificity of Xpert in routine programme conditions were evaluated using culture and phenotypic drug susceptibility testing (DST) as gold standard. Contribution to early start of treatment for multidrug-resistant tuberculosis (MDR-TB) was expressed as the median time between availability of the test result and start of treatment.. Compared to culture, the sensitivity and specificity of Xpert were respectively 92.7% and 90.4%. For the detection of rifampicin (RMP) resistance, Xpert sensitivity and specificity were respectively 90.1% and 90.7%. The median time to initiation of MDR-TB treatment decreased to 10 days (interquartile range [IQR] 6-16) in 2014 from 20 days (IQR 12-40, P < 0.001) in 2013.. The Xpert assay demonstrated good agreement in the detection of both Mycobacterium tuberculosis and RMP-resistant pulmonary TB in routine clinical practice. Although Xpert improved the time to treatment initiation from 2013 to 2014, more efforts are needed to further reduce this delay.

Topics: Antibiotics, Antitubercular; Humans; Kyrgyzstan; Mycobacterium tuberculosis; Primary Health Care; Real-Time Polymerase Chain Reaction; Retrospective Studies; Rifampin; Sensitivity and Specificity; Time Factors; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Current diagnostic tools for Mycobacterium tuberculosis (Mtb) have many disadvantages including low sensitivity, slow turnaround times, or high cost. Accurate, easy to use, and inexpensive point of care molecular diagnostic tests are urgently needed for the analysis of multidrug resistant (MDR) and extensively drug resistant (XDR) Mtb strains that emerge globally as a public health threat. In this study, we established proof-of-concept for a novel diagnostic platform (TB-DzT) for Mtb detection and the identification of drug resistant mutants using binary deoxyribozyme sensors (BiDz). TB-DzT combines a multiplex PCR with single nucleotide polymorphism (SNP) detection using highly selective BiDz sensors targeting loci associated with species typing and resistance to rifampin, isoniazid and fluoroquinolone antibiotics. Using the TB-DzT assay, we demonstrated accurate detection of Mtb and 5 mutations associated with resistance to three anti-TB drugs in clinical isolates. The assay also enables detection of a minority population of drug resistant Mtb, a clinically relevant scenario referred to as heteroresistance. Additionally, we show that TB-DzT can detect the presence of unknown mutations at target loci using combinatorial BiDz sensors. This diagnostic platform provides the foundation for the development of cost-effective, accurate and sensitive alternatives for molecular diagnostics of MDR- and XDR-TB.

Topics: Biosensing Techniques; DNA, Catalytic; Extensively Drug-Resistant Tuberculosis; Humans; Isoniazid; Microbial Sensitivity Tests; Multiplex Polymerase Chain Reaction; Mutation; Mycobacterium tuberculosis; Polymorphism, Single Nucleotide; Rifampin; Tuberculosis, Multidrug-Resistant

Topics: Antibiotics, Antitubercular; Bacteriological Techniques; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Real-Time Polymerase Chain Reaction; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Twenty-four quinoxaline derivatives were evaluated for their antimycobacterial activity using BacTiter-Glo microbial cell viability assay. Five compounds showed MIC values <3.1 μM and IC50 values<1.5 μM in primary screening and therefore, they were moved on for further evaluation. Compounds 21 and 18 stand out, showing MIC values of 1.6 μM and IC50 values of 0.5 and 1.0 μM, respectively. Both compounds were the most potent against three evaluated drug-resistant strains. Moreover, they exhibited intracellular activity in infected macrophages, considering log-reduction and cellular viability. In addition, compounds 16 and 21 were potent against non-replicating Mycobacterium tuberculosis and compound 21 was bactericidal. Therefore, quinoxaline derivatives could be considered for making further advances in the future development of antimycobacterial agents.

Topics: Animals; Antitubercular Agents; Cell Line; Cyclic N-Oxides; Drug Resistance, Multiple, Bacterial; Latent Tuberculosis; Mice; Mycobacterium tuberculosis; Quinoxalines; Tuberculosis, Multidrug-Resistant

Our team had previously identified certain indolecarboxamides that represented a new chemical scaffold that showed promising anti-TB activity at both an in vitro and in vivo level. Based on mutational analysis using bacteria found resistant to one of these indolecarboxamides, we identified the trehalose monomycolate transporter MmpL3 as the likely target of these compounds. In the present work, we now further elaborate on the SAR of these compounds, which has led in turn to the identification of a new analog, 4,6-difluoro-N-((1R,2R,3R,5S)-2,6,6-trimethylbicyclo[3.1.1]heptan-3-yl)-1H-indole-2-carboxamide (26), that shows excellent activity against drug-sensitive (MIC = 0.012 μM; SI ≥ 16000), multidrug-resistant (MDR), and extensively drug-resistant (XDR) Mycobacterium tuberculosis strains, has superior ADMET properties, and shows excellent activity in the TB aerosol lung infection model. Compound 26 is also shown to work in synergy with rifampin. Because of these properties, we believe that indolecarboxamide 26 is a possible candidate for advancement to human clinical trials.

Topics: Animals; Antitubercular Agents; Bacterial Proteins; Disease Models, Animal; Drug Design; Female; Humans; Indoles; Membrane Transport Proteins; Mice, Inbred BALB C; Microbial Sensitivity Tests; Models, Molecular; Molecular Docking Simulation; Molecular Targeted Therapy; Mycobacterium tuberculosis; Tuberculosis; Tuberculosis, Multidrug-Resistant

Mutations in several genetic loci have been implicated in the development of resistance to second-line anti-tuberculosis (TB) drugs (SLDs). The purpose of this study was to investigate the prevalence of resistance to SLDs and its association with specific mutations in multidrug-resistant (MDR) Mycobacterium tuberculosis clinical isolates.. The study included 46 MDR-TB isolates. Mutation profiling was performed by amplifying and sequencing the following six genes: gyrA/gyrB, rrs, tlyA, and ethA/ethR, in which mutations are implicated in resistance of tubercle bacilli to ofloxacin (OFX), amikacin (AMK), capreomycin, and ethionamide (ETH), respectively.. Of the strains analyzed, 14 (30.4%) showed resistance to at least one of the four SLDs tested. Mutations in the gyrA gene occurred in 34 (73.9%) strains, with the most common amino acid change being Ser95Thr. The Asp94Asn and Ala90Val substitutions in the gyrA were present exclusively in OFX-resistant strains, yet represented only 40% of all OFX-resistant strains. The only mutation in the gyrB gene was substitution Ser447Phe, detected in one OFX-resistant isolate. None of the AMK-resistant strains carried a mutation in the rrs gene. Mutations in the ethA/ethR loci were found in one ETH-resistant and 11 ETH-susceptible strains.. The results of this study challenge the usefulness of sequence analyses of tested genes (except gyrA) for the prediction of SLD resistance patterns and highlight the need for searching other genetic loci for detection of mutations conferring resistance to SLDs in M. tuberculosis.

Topics: Adult; Aged; Amikacin; Antitubercular Agents; Base Sequence; Capreomycin; DNA Gyrase; Drug Resistance, Multiple, Bacterial; Ethionamide; Female; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Mutation; Mycobacterium tuberculosis; Ofloxacin; Oxidoreductases; Rifampin; Sequence Analysis, DNA; Tuberculosis, Multidrug-Resistant

The widespread occurrence of drug-resistant Mycobacterium tuberculosis places importance on the detection of TB (tuberculosis) drug susceptibility. Conventional drug susceptibility testing (DST) is a lengthy process. We developed a rapid enzymatic color-reaction-based biochip assay. The process included asymmetric multiplex PCR/templex PCR, biochip hybridization, and an enzymatic color reaction, with specific software for data operating. Templex PCR (tem- PCR) was applied to avoid interference between different primers in conventional multiplex- PCR. We applied this assay to 276 clinical specimens (including 27 sputum, 4 alveolar lavage fluid, 2 pleural effusion, and 243 culture isolate specimens; 40 of the 276 were non-tuberculosis mycobacteria specimens and 236 were M. tuberculosis specimens). The testing process took 4.5 h. A sensitivity of 50 copies per PCR was achieved, while the sensitivity was 500 copies per PCR when tem-PCR was used. Allele sequences could be detected in mixed samples at a proportion of 10%. Detection results showed a concordance rate of 97.46% (230/236) in rifampicin resistance detection (sensitivity 95.40%, specificity 98.66%) and 96.19% (227/236) in isoniazid (sensitivity 93.59%, specificity 97.47%) detection with those of DST assay. Concordance rates of testing results for sputum, alveolar lavage fluid, and pleural effusion specimens were 100%. The assay provides a potential choice for TB diagnosis and treatment.

Topics: Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Humans; Isoniazid; Microarray Analysis; Microbial Sensitivity Tests; Multiplex Polymerase Chain Reaction; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

To overcome the undesirable side effects and reduce the cytotoxicity of isoniazid (INH) and rifampin (RMP) in the digestive tract, a poly(methacrylic acid) (PMAA) nanogel was developed as a carrier of INH and RMP. This PMAA/INH/RMP nanogel was prepared as a treatment for intestinal tuberculosis caused by multidrug-resistant Mycobacterium tuberculosis (MTB). The morphology, size, and in vitro release properties were evaluated in a simulated gastrointestinal medium, and long-term antibacterial performance, cytotoxicity, stability, and activity of this novel PMAA/INH/RMP nanogel against multidrug-resistant MTB in the intestine were investigated. Our results indicate that the PMAA/INH/RMP nanogel exhibited extended antibacterial activity by virtue of its long-term release of INH and RMP in the simulated gastrointestinal medium. Further, this PMAA/INH/RMP nanogel exhibited lower cytotoxicity than did INH or RMP alone, suggesting that this PMAA/INH/RMP nanogel could be a more useful dosage form than separate doses of INH and RMP for intestinal MTB. The novel aspects of this study include the cytotoxicity study and the three-phase release profile study, which might be useful for other researchers in this field.

Topics: Animals; Antitubercular Agents; Cell Survival; Drug Stability; Humans; Isoniazid; Mice; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Nanogels; NIH 3T3 Cells; Polyethylene Glycols; Polyethyleneimine; Polymethacrylic Acids; Rifampin; Tuberculosis, Gastrointestinal; Tuberculosis, Multidrug-Resistant

Our objective was to assess the cost-benefit of enhancing or replacing the conventional sputum smear with the real-time PCR Xpert MTB/RIF method in the inpatient diagnostic schema for tuberculosis (TB).Recent data from published per-case cost studies for TB/multidrug-resistant (MDR)-TB and from comparative analyses of sputum microscopy, mycobacterial culture, Xpert MTB/RIF and drug susceptibility testing, performed at the German National Reference Center for Mycobacteria, were used. Potential cost savings of Xpert MTB/RIF, based on test accuracy and multiple cost drivers, were calculated for diagnosing TB/MDR-TB suspects from the hospital perspective.Implementing Xpert MTB/RIF as an add-on in smear-positive and smear-negative TB suspects saves on average €48.72 and €503, respectively, per admitted patient as compared with the conventional approach. In smear-positive and smear-negative MDR-TB suspects, cost savings amount to €189.56 and €515.25 per person, respectively. Full replacement of microscopy by Xpert MTB/RIF saves €449.98. In probabilistic Monte-Carlo simulation, adding Xpert MTB/RIF is less costly in 46.4% and 76.2% of smear-positive TB and MDR-TB suspects, respectively, but 100% less expensive in all smear-negative suspects. Full replacement by Xpert MTB/RIF is also consistently cost-saving.Using Xpert MTB/RIF as an add-on to and even as a replacement for sputum smear examination may significantly reduce expenditures in TB suspects.

Topics: Bacterial Proteins; Cost-Benefit Analysis; DNA-Directed RNA Polymerases; Europe; Germany; Hospital Costs; Hospitalization; Humans; Microscopy; Models, Economic; Mycobacterium tuberculosis; Real-Time Polymerase Chain Reaction; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

We aimed to evaluate the GeneXpert® MTB/RIF test for the diagnosis of extrapulmonary tuberculosis. The test simultaneously detects Mycobacterium tuberculosis complex and resistance to rifampicin.. We analyzed 153 clinical samples collected in a tertiary hospital in Sfax, Tunisia, between 2013 and 2014. We performed the GeneXpert® test, a Ziehl-Neelsen and auramine-rhodamine staining, conventional culture on MGIT 960 and LJ media, and we tested the resistance to anti-tuberculosis drugs on MGIT 960 and LJ media for each sample. Diagnosis was based on clinical, radiological, microbiological, pathological, and therapeutic data.. We considered that 59 patients out of 153 presented with tuberculosis. PCR was positive in 50 samples and all of these samples were susceptible to rifampicin. Sensitivity, specificity, positive predictive value, and negative predictive value of the GeneXpert® test were 84.7%, 96.8%, 94.3%, and 91%, respectively, compared with diagnosis. We observed a statistically significant difference between the direct test and the GeneXpert® test, and between culture and the GeneXpert® test. No statistically significant difference was observed between pathological results and the GeneXpert® test. Sensitivity of the GeneXpert® test was 87.5% in biopsies, 80% in pus and abscesses, and 66.7% in biological fluids. All strains were susceptible to rifampicin with culture and GeneXpert® test.. The GeneXpert® test helped detect a higher proportion of M. tuberculosis complex. It does not replace conventional diagnostic methods but it is a useful addition to achieve better sensitivity and obtain rapid results.

Topics: Abscess; Antitubercular Agents; Biopsy; Body Fluids; DNA, Bacterial; Drug Resistance; Female; HIV Seronegativity; Humans; Male; Mycobacterium tuberculosis; Polymerase Chain Reaction; Predictive Value of Tests; Retrospective Studies; Rifampin; Sensitivity and Specificity; Staining and Labeling; Suppuration; Tuberculosis; Tuberculosis, Multidrug-Resistant

This case study examines the ethical dimensions of isolation for patients diagnosed with tuberculosis (TB) in Australia. It seeks to explore the issues of resource allocation, liberty, and public safety for wider consideration and discussion.

Topics: Adult; Antitubercular Agents; Australia; Ethics, Institutional; Family; Humans; Isoniazid; Male; Mycobacterium tuberculosis; Patient Isolation; Rifampin; Sputum; Transients and Migrants; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Many hospital inpatients in South Africa have undiagnosed active and drug-resistant tuberculosis (TB). Early detection of TB is essential to inform immediate infection control actions to minimize transmission risk. We assessed the utility of Xpert(®) MTB/RIF (GeneXpert) as a screening tool for medical admissions at a large public hospital in South Africa. Consecutive adult patients admitted to medical wards between March-June 2013 were enrolled; sputum specimens were collected and tested by GeneXpert, smear microscopy, and culture. Chest X-rays (CXRs) were conducted as standard care for all patients admitted. We evaluated the proportion of patients identified with TB disease through each diagnostic method. Among enrolled patients whose medical charts were available for review post-discharge, 61 (27%) were diagnosed with TB; 34 (56% of diagnosed TB cases) were GeneXpert positive. When patients in whom TB was identified by other means were excluded, GeneXpert yielded only four additional TB cases. However, GeneXpert identified rifampicin-resistant TB in one patient, who was initially diagnosed based on CXR. The utility of GeneXpert for TB screening was limited in an institution where CXR is conducted routinely and which serves a population in which TB and TB/HIV co-infection are highly prevalent, but it allowed for rapid detection of rifampicin resistance.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Coinfection; Drug Resistance, Bacterial; Female; HIV Infections; Humans; Male; Mass Screening; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Reproducibility of Results; Rifampin; South Africa; Tuberculosis, Multidrug-Resistant; Young Adult

Topics: Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Fluoroquinolones; Humans; Mycobacterium tuberculosis; Pyrazinamide; Rifampin; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Fluoroquinolones; Humans; Mycobacterium tuberculosis; Pyrazinamide; Rifampin; Tuberculosis, Multidrug-Resistant

Topics: Commerce; DNA, Bacterial; Health Care Costs; Health Care Sector; Health Services Accessibility; Humans; Molecular Diagnostic Techniques; Mycobacterium tuberculosis; Private Sector; Rifampin; Tuberculosis, Multidrug-Resistant

Developing a fast, inexpensive, and specific test that reflects the mutations present in Mycobacterium tuberculosis isolates according to geographic region is the main challenge for drug-resistant tuberculosis (TB) control. The objective of this study was to develop a molecular platform to make a rapid diagnosis of multidrug-resistant (MDR) and extensively drug-resistant TB based on single nucleotide polymorphism (SNP) mutations present in therpoB, katG, inhA,ahpC, and gyrA genes from Colombian M. tuberculosis isolates. The amplification and sequencing of each target gene was performed. Capture oligonucleotides, which were tested before being used with isolates to assess the performance, were designed for wild type and mutated codons, and the platform was standardised based on the reverse hybridisation principle. This method was tested on DNA samples extracted from clinical isolates from 160 Colombian patients who were previously phenotypically and genotypically characterised as having susceptible or MDR M. tuberculosis. For our method, the kappa index of the sequencing results was 0,966, 0,825, 0,766, 0,740, and 0,625 forrpoB, katG, inhA,ahpC, and gyrA, respectively. Sensitivity and specificity were ranked between 90-100% compared with those of phenotypic drug susceptibility testing. Our assay helps to pave the way for implementation locally and for specifically adapted methods that can simultaneously detect drug resistance mutations to first and second-line drugs within a few hours.

Topics: Antibiotics, Antitubercular; Colombia; DNA, Bacterial; Extensively Drug-Resistant Tuberculosis; Fluoroquinolones; Gene Amplification; Humans; Isoniazid; Molecular Diagnostic Techniques; Mutation; Mycobacterium tuberculosis; Nucleic Acid Hybridization; Polymorphism, Single Nucleotide; Rifampin; Sequence Analysis, DNA; Tuberculosis, Multidrug-Resistant

The failure of current Standard Short-Course Chemotherapy (SCC) in new and previously treated cases with tuberculosis (TB) was mainly due to drug resistance development. But little is known on the characteristics of acquired drug resistant TB during SCC and its correlation with SCC failure. The objective of the study is to explore the traits of acquired drug resistant TB emergence and evaluate their impacts on treatment outcomes.. A prospective observational study was performed on newly admitted smear positive pulmonary TB (PTB) cases without drug resistance pretreatment treated with SCC under China's National TB Control Program (NTP) condition from 2008 to 2010. Enrolled cases were followed up through sputum smear, culture and drug susceptibility testing (DST) at the end of 1, 2, and 5 months after treatment initiation. The effect factors of early or late emergence of acquired drug resistant TB , such as acquired drug resistance patterns, the number of acquired resistant drugs and previous treatment history were investigated by multivariate logistic regression; and the impact of acquired drug resistant TB emergence on treatment failure were further evaluated.. Among 1671 enrolled new and previously treated cases with SCC, 62 (3.7%) acquired different patterns of drug resistant TB at early period within 2 months or later around 3-5 months of treatment. Previously treated cases were more likely to develop acquired multi-drug resistant TB (MDR-TB) (OR, 3.8; 95%CI, 1.4-10.4; P = 0.015). Additionally, acquired MDR-TB cases were more likely to emerge at later period around 3-5 months after treatment starting than that of non-MDR-TB mainly appeared within 2 months (OR, 8.3; 95%CI, 1.7-39.9; P = 0.008). Treatment failure was associated with late acquired drug resistant TB emergence (OR, 25.7; 95%CI, 4.3-153.4; P < 0.001) with the reference of early acquired drug resistant TB emergence.. This study demonstrates that later development of acquired drug resistant TB during SCC is liable to suffer treatment failure and acquired MDR-TB pattern may be one of the possible causes.

Topics: Adolescent; Adult; Antitubercular Agents; China; Cohort Studies; Drug Resistance, Bacterial; Drug Therapy, Combination; Ethambutol; Female; Humans; Isoniazid; Male; Middle Aged; Mycobacterium tuberculosis; Prospective Studies; Pyrazinamide; Rifampin; Streptomycin; Treatment Failure; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

The extent to which the Xpert MTB/RIF (Gene Xpert) contributes to tuberculosis (TB) diagnosis in samples other than sputum and cerebrospinal fluid remains uncertain. We aimed to assess the role of Xpert MTB/RIF for detecting M. tuberculosis in post-mortem tissues. We conducted a study among 30 complete diagnostic autopsies (CDA) performed at the Maputo Central Hospital (Mozambique). Lung tissues were screened for TB in all cases. In addition other tissues were tested when compatible lesions were identified in the histological exam. We used in-house real time PCR and LAMP assays to confirm the presence of M. tuberculosis DNA. The diagnosis of tuberculosis at death was established based on microbiological and histopathological results. Eight out of 30 cases (26.7%) were diagnosed of tuberculosis. Xpert had a sensitivity to detect TB in lung tissue of 87.5% (95% CI 47.3-99.7) and a specificity of 95.7% (95% CI: 78.1-99.9). In-house DNA amplification methods and Xpert showed 93.6% concordance for lung tissue and 100% concordance for brain and liver tissues. The final cause of death was attributable to tuberculosis in four cases. Xpert MTB/RIF may represent a valuable, easy-to perform technique for post-mortem TB diagnosis.

Topics: Adolescent; Adult; Aged; Brain; Cause of Death; DNA, Bacterial; Drug Resistance, Multiple, Bacterial; Female; Humans; Liver; Lung; Male; Middle Aged; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Reagent Kits, Diagnostic; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

Topics: Amikacin; Antitubercular Agents; Capreomycin; Extensively Drug-Resistant Tuberculosis; Fluoroquinolones; Humans; India; Isoniazid; Kanamycin; Medication Adherence; Mycobacterium tuberculosis; Nonprescription Drugs; Rifampin; Tuberculosis, Multidrug-Resistant

Few studies have examined whether the Xpert MTB/RIF test improves time to treatment initiation for persons with multidrug-resistant tuberculosis (MDR TB). We determined the impact of this test in Latvia, where it was introduced in 2010. After descriptive analyses of pulmonary MDR TB patients in Latvia during 2009-2012, time to treatment initiation was calculated, and univariate and multivariable accelerated failure time models were constructed. Univariate results showed strong evidence of an association between having rifampin-resistant TB detected by Xpert MTB/RIF and reduced time to treatment initiation versus the test not being used. A multivariable model stratifying by previous TB showed similar results. Our finding that in Latvia, time to treatment initiation was decreased for MDR TB cases that were rifampin-resistant TB by XpertMTB/RIF has implications for the use of this test in other settings with a high burden of MDR TB in which rifampin resistance is highly predictive of MDR TB.

Topics: Adolescent; Adult; Antibiotics, Antitubercular; Drug Resistance, Microbial; Female; Humans; Latvia; Male; Middle Aged; Mycobacterium tuberculosis; Rifampin; Time-to-Treatment; Tuberculin Test; Tuberculosis, Multidrug-Resistant; Young Adult

Mycobacterium tuberculosis can acquire resistance to rifampin (RIF) through mutations in the rpoB gene. This is usually accompanied by a fitness cost, which, however, can be mitigated by secondary mutations in the rpoA or rpoC gene. This study aimed to identify rpoA and rpoC mutations in clinical M. tuberculosis isolates in northern China in order to clarify their role in the transmission of drug-resistant tuberculosis (TB). The study collection included 332 RIF-resistant and 178 RIF-susceptible isolates. The majority of isolates belonged to the Beijing genotype (95.3%, 486/510 isolates), and no mutation was found in rpoA or rpoC of the non-Beijing genotype strains. Among the Beijing genotype strains, 27.8% (89/320) of RIF-resistant isolates harbored nonsynonymous mutations in the rpoA (n = 6) or rpoC (n = 83) gene. The proportion of rpoC mutations was significantly higher in new cases (P = 0.023) and in strains with the rpoB S531L mutation (P < 0.001). In addition, multidrug-resistant (MDR) strains with rpoC mutations were significantly associated with 24-locus mycobacterial interspersed repetitive-unit-variable-number tandem-repeat clustering (P = 0.016). In summary, we believe that these findings indirectly suggest an epistatic interaction of particular mutations related to RIF resistance and strain fitness and, consequently, the role of such mutations in the spread of MDR M. tuberculosis strains.

Topics: Bacterial Proteins; China; Drug Resistance, Multiple, Bacterial; Genotype; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

We report investigation of 22 TB cases with positive Xpert MTB/RIF result for resistance to Rifampin and "Very Low" MTB detection level. Twelve cases were false positive without rpoB mutations, 2 were false-positives with a silent mutation in rpoB codon T508, and only 10 were true positives.

Topics: Bacterial Load; Humans; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Real-Time Polymerase Chain Reaction; Reproducibility of Results; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Understanding the circulating Mycobacterium tuberculosis resistance mutations is vital for better TB control strategies, especially to inform a new MDR-TB treatment programme. We complemented the phenotypic drug susceptibility testing (DST) based drug resistance surveys (DRSs) conducted in Uganda between 2008 and 2011 with Whole Genome Sequencing (WGS) of 90 Mycobacterium tuberculosis isolates phenotypically resistant to rifampicin and/or isoniazid to better understand the extent of drug resistance. A total of 31 (34.4 %) patients had MDR-TB, 5 (5.6 %) mono-rifampicin resistance and 54 (60.0 %) mono-isoniazid resistance by phenotypic DST. Pyrazinamide resistance mutations were identified in 32.3% of the MDR-TB patients. Resistance to injectable agents was detected in 4/90 (4.4%), and none to fluoroquinolones or novel drugs. Compensatory mutations in rpoC were identified in two patients. The sensitivity and specificity of drug resistance mutations compared to phenotypic DST were for rpoB 88.6% and 98.1%, katG 60.0% and 100%, fabG1 16.5% and 100%, katG and/or fabG1 71.8% and 100%, embCAB 63.0% and 82.5%, rrs 11.4% and 100%, rpsL 20.5% and 95.7% and rrs and/or rpsL 31.8% and 95.7%. Phylogenetic analysis showed dispersed MDR-TB isolate, with only one cluster of three Beijing family from South West Uganda. Among tuberculosis patients in Uganda, resistance beyond first-line drugs as well as compensatory mutations remain low, and MDR-TB isolates did not arise from a dominant clone. Our findings show the potential use of sequencing for complementing DRSs or surveillance in this setting, with good specificity compared to phenotypic DST. The reported high confidence mutations can be included in molecular assays, and population-based studies can track transmission of MDR-TB including the Beijing family strains in the South West of the country.

Topics: Adult; Antitubercular Agents; Bacterial Proteins; Female; Genome, Bacterial; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Mutation; Mycobacterium tuberculosis; Phylogeny; Pyrazinamide; Rifampin; Sequence Analysis, DNA; Tuberculosis, Multidrug-Resistant; Uganda; Young Adult

Tuberculosis remains a major public health challenge for India. Various studies have documented different levels of TB and multi-drug resistant (MDR) TB among diverse groups of the population. In view of renewed targets set under the End TB strategy by 2035, there is an urgent need for TB diagnosis to be strengthened. Drawing on data from a recent, multisite study, we address key questions for TB diagnosis amongst symptomatics presenting for care: are there subgroups of patients that are more likely than others, to be positive for TB? In turn, amongst these positive cases, are there factors-apart from treatment history-that may be predictive for multi-drug resistance?. We used data from a multi-centric prospective demonstration study, conducted from March 2012 to December 2013 in 18 sub-district level TB programme units (TUs) in India and covering a population of 8.8 million. In place of standard diagnostic tests, upfront Xpert MTB/RIF testing was offered to all presumptive TB symptomatics. Here, using data from this study, we used logistic regression to identify association between risk factors and TB and Rifampicin-Resistant TB among symptomatics enrolled in the study.. We find that male gender; history of TB treatment; and adult age compared with either children or the elderly are risk factors associated with high TB detection amongst symptomatics, across the TUs. While treatment history is found be a significant risk factor for rifampicin-resistant TB, elderly (65+ yrs) people have significantly lower risk than other age groups. However, pediatric TB cases have no less risk of rifampicin resistance as compared with adults (OR 1.23 (95% C.I. 0.85-1.76)). Similarly, risk of rifampicin resistance among both the genders was the same. These patterns applied across the study sites involved. Notably in Mumbai, amongst those patients with microbiological confirmation of TB, female patients showed a higher risk of having MDR-TB than male patients.. Our results cast fresh light on the characteristics of symptomatics presenting for care who are most likely to be microbiologically positive for TB, and for rifampicin resistance. The challenges posed by TB control are complex and multifactorial: evidence from diverse sources, including retrospective studies such as that addressed here, can be invaluable in informing future strategies to accelerate declines in TB burden.

Topics: Adolescent; Adult; Age Factors; Aged; Aged, 80 and over; Antibiotics, Antitubercular; Child; Drug Resistance, Bacterial; Female; Humans; India; Male; Middle Aged; Retrospective Studies; Rifampin; Risk Factors; Sex Factors; Tuberculosis; Tuberculosis, Multidrug-Resistant; Young Adult

To gain insight into the epidemiology of childhood drug resistant tuberculosis (DR-TB) in China that has the second largest burden of TB and the largest number of multidrug resistant (MDR) TB cases in the world, we performed the cross-sectional study to investigate drug resistance of four first-line anti-TB drugs (isoniazid, rifampicin, streptomycin and ethambutol) using Mycobacterium tuberculosis isolates from 196 culture-confirmed pediatric TB cases diagnosed in the Children's Hospital of Chongqing Medical University, China during 2008-2013. Univariate and multivariate logistic regression analyses were performed to assess the associations between patient demographic and clinical characteristics and DR-and MDR-TB, respectively. Twenty-eight percent (56/196) of the study patients exhibited resistance to at least one of the four first-line anti-TB drugs tested. MDR was found in 4.6% (9/196) of the study patients. More than half (5/9, 55.6%) of the MDR cases were from a single county of Chongqing. A significant association was found between being acid-fast bacilli-smear negative and DR-TB (adjusted OR, 2.33; 95% CI, 1.13-4.80) and between having concurrent thoracic-extrathoracic involvement and MDR-TB (adjusted OR, 9.49; 95% CI, 1.05-85.92), respectively. The findings of this study indicate that the rate of DR is high among pediatric TB patients in Chongqing and suggest an urgent need for studies to identify MDR transmission hotspots in Chongqing, thereby contributing to the control DR- and MDR-TB epidemics in China. The study also generates new insight into the pathogenesis of DR and MDR M. tuberculosis strains and highlights the importance of studying childhood TB to the goal of global TB control.

Topics: Adolescent; Antitubercular Agents; Child; Child, Preschool; China; Cross-Sectional Studies; Ethambutol; Female; Humans; Infant; Isoniazid; Logistic Models; Male; Rifampin; Tuberculosis, Multidrug-Resistant

The first national anti-tuberculosis drug resistance survey in Pakistan, a high tuberculosis (TB) and low human immunodeficiency virus (HIV) burden country.. To determine the proportion of patients with multidrug-resistant TB (MDR-TB) and to compare the performance of Xpert(®) MTB/RIF with conventional phenotypic drug susceptibility testing (DST).. Sputum samples were collected from 1972 consecutively enrolled pulmonary TB patients from 40 clusters. Phenotypic DST was performed in parallel with Xpert.. The proportion of MDR-TB patients was 3.7% (95%CI 2.5-5.0) among new and 18.1% (95%CI 13.0-23.4) among previously treated cases. A valid rifampicin (RMP) testing result was available from substantially more cases with Xpert (n = 1809) than with phenotypic DST (n = 1592). Among strains with discordant results, rpoB sequencing revealed only one false-resistant result (new TB case) with Xpert and 7.7% (8/104) of RMP-resistant cases missed with Xpert against 3.8% (4/14) by phenotypic DST. This difference was not significant.. This survey provides the first representative data for Pakistan on its MDR-TB burden. The Xpert assay had nearly 100% specificity, even in a low MDR-TB prevalence setting. The use of this assay greatly simplifies survey logistics, making it a feasible option for survey implementation, especially in resource-constrained settings.

Topics: Adolescent; Adult; Aged; Antibiotics, Antitubercular; Cluster Analysis; Cross-Sectional Studies; Drug Resistance, Multiple, Bacterial; Feasibility Studies; Female; Humans; Logistic Models; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Pakistan; Prevalence; Reproducibility of Results; Rifampin; Sensitivity and Specificity; Sputum; Surveys and Questionnaires; Tuberculosis, Multidrug-Resistant; Young Adult

For an effective control of tuberculosis, rapid detection of multidrug resistant tuberculosis (MDR-TB) is necessary. Therefore, we developed a modified nested multiplex allele-specific polymerase chain reaction (MAS-PCR) method that enables rapid MDR-TB detection directly from sputum samples. The efficacy of this method was evaluated using 79 sputum samples collected from suspected tuberculosis patients. The performance of nested MAS-PCR method was compared with other MDR-TB detection methods like drug susceptibility testing (DST) and DNA sequencing. As rifampicin (RIF) resistance conforms to MDR-TB in greater than 90% cases, only the presence of RIF-associated mutations in rpoB gene was determined by DNA sequencing and nested MAS-PCR to detect MDR-TB. The concordance between nested MAS-PCR and DNA sequencing results was found to be 96·3%. When compared with DST, the sensitivity and specificity of nested MAS-PCR for RIF-resistance detection were determined to be 92·9 and 100% respectively.. For developing- and high-TB burden countries, molecular-based tests have been recommended by the World Health Organization for rapid detection of MDR-TB. The results of this study indicate that, nested MAS-PCR assay might be a practical and relatively cost effective molecular method for rapid detection of MDR-TB from suspected sputum samples in developing countries with resource poor settings.

Topics: Adult; Alleles; Antitubercular Agents; Bacterial Proteins; DNA-Directed RNA Polymerases; Drug Resistance, Multiple, Bacterial; Female; Humans; Isoniazid; Multiplex Polymerase Chain Reaction; Mycobacterium tuberculosis; Rifampin; Sequence Analysis, DNA; Sputum; Tuberculosis, Multidrug-Resistant

In 2013 alone, the death rate among the 9.0 million people infected with Mycobacterium tuberculosis (TB) worldwide was around 14%, which is unacceptably high. An empiric treatment of patients infected with TB or drug-resistant Mycobacterium tuberculosis (MDR-TB) strain can also result in the spread of MDR-TB. The diagnostic tools which are rapid, reliable, and have simple experimental protocols can significantly help in decreasing the prevalence rate of MDR-TB strain. We report the evaluation of the 9G technology based 9G DNAChips that allow accurate detection and discrimination of TB and MDR-TB-RIF. One hundred and thirteen known cultured samples were used to evaluate the ability of 9G DNAChip in the detection and discrimination of TB and MDR-TB-RIF strains. Hybridization of immobilized probes with the PCR products of TB and MDR-TB-RIF strains allow their detection and discrimination. The accuracy of 9G DNAChip was determined by comparing its results with sequencing analysis and drug susceptibility testing. Sequencing analysis showed 100% agreement with the results of 9G DNAChip. The 9G DNAChip showed very high sensitivity (95.4%) and specificity (100%).

Topics: Biosensing Techniques; Drug Resistance, Microbial; Humans; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Although there is substantial risk to maternal and neonatal health in the situation of pregnancy during treatment for rifampicin-resistant tuberculosis (RR-TB), there is little evidence to guide clinicians as to how to manage this complexity. Of the 49 680 patients initiated on RR-TB treatment from 2009 to 2014 in South Africa, 47% were women and 80% of them were in their reproductive years (15 - 44). There is an urgent need for increased evidence of the safety of RR-TB treatment during pregnancy, increased access to contraception during RR-TB treatment, and inclusion of reproductive health in research on the prevention and treatment of TB.

Topics: Adolescent; Adult; Antibiotics, Antitubercular; Contraception; Evidence-Based Medicine; Female; Humans; Male; Pregnancy; Pregnancy Complications, Infectious; Rifampin; South Africa; Tuberculosis, Multidrug-Resistant; Young Adult

Recent advances have made molecular diagnosis of tuberculosis (TB) and drug susceptibility testing (DST) possible, but the high costs involved present a huge challenge. The refinement and improvement of affordable methods therefore remain a priority. Conventional indirect DST is inexpensive and reliable, but time-consuming. A direct DST method for the direct testing of sputum samples without culture has been developed to reduce the time required for DST, but there have been conflicting results.. Direct and indirect DST against isoniazid and rifampicin were performed on 208 sputum smear-positive specimens, 186 from newly diagnosed patients and 22 from previously treated patients; respectively 169 and 180 of the direct and indirect DST results were reportable. In comparison with indirect DST, direct DST resulted in a saving of on average 10.5 days. The time to direct DST results was inversely correlated with the number of acid-fast bacilli in the sputum samples.. Direct DST is highly sensitive, reliable, cost-effective and time-saving in comparison with indirect DST.

Topics: Antitubercular Agents; China; Cost-Benefit Analysis; Drug Resistance, Bacterial; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Specimen Handling; Sputum; Tuberculosis, Multidrug-Resistant

Electronic diagnostic tests, such as the Xpert® MTB/RIF assay, are being implemented in low- and middle-income countries (LMICs). However, timely information from these tests available via remote monitoring is underutilized. The failure to transmit real-time, actionable data to key individuals such as clinicians, patients, and national monitoring and evaluation teams may negatively impact patient care.. To describe recently developed applications that allow for real-time, remote monitoring of Xpert results, and initial implementation of one of these products in central Mozambique.. In partnership with the Mozambican National Tuberculosis Program, we compared three different remote monitoring tools for Xpert and selected one, GxAlert, to pilot and evaluate at five public health centers in Mozambique.. GxAlert software was successfully installed on all five Xpert computers, and test results are now uploaded daily via a USB internet modem to a secure online database. A password-protected web-based interface allows real-time analysis of test results, and 1200 positive tests for tuberculosis generated 8000 SMS result notifications to key individuals.. Remote monitoring of diagnostic platforms is feasible in LMICs. While promising, this effort needs to address issues around patient data ownership, confidentiality, interoperability, unique patient identifiers, and data security.

Topics: Antibiotics, Antitubercular; Developing Countries; Drug Resistance, Multiple, Bacterial; Feasibility Studies; Humans; Internet; Mozambique; Mycobacterium tuberculosis; Pilot Projects; Remote Consultation; Rifampin; Software; Sputum; Tuberculosis, Multidrug-Resistant

KwaZulu-Natal (KZN) has the highest burden of notified multidrug-resistant tuberculosis (MDR TB) and extensively drug-resistant (XDR) TB cases in South Africa. A better understanding of spatial heterogeneity in the risk of drug-resistance may help to prioritize local responses.. Between July 2012 and June 2013, we conducted a two-way Lot Quality Assurance Sampling (LQAS) study to classify the burden of rifampicin (RIF)-resistant TB among incident TB cases notified within the catchment areas of seven laboratories in two northern and one southern district of KZN. Decision rules for classification of areas as having either a high- or low-risk of RIF resistant TB (based on proportion of RIF resistance among all TB cases) were based on consultation with local policy makers.. We classified five areas as high-risk and two as low-risk. High-risk areas were identified in both Southern and Northern districts, with the greatest proportion of RIF resistance observed in the northernmost area, the Manguzi community situated on the Mozambique border.. Our study revealed heterogeneity in the risk of RIF resistant disease among incident TB cases in KZN. This study demonstrates the potential for LQAS to detect geographic heterogeneity in areas where access to drug susceptibility testing is limited.

Topics: Adolescent; Adult; Antitubercular Agents; Female; Humans; Male; Middle Aged; Prospective Studies; Quality Control; Retrospective Studies; Rifampin; Risk Factors; Sensitivity and Specificity; South Africa; Tuberculosis, Multidrug-Resistant; Young Adult

Multidrug-resistant tuberculosis (MDR-TB) is defined as resistance to at least isoniazid (INH) and rifampicin (RIF), and it complicates the implementation of tuberculosis control programmes. The rapid detection of MDR-TB is crucial to reduce the transmission of disease. The nitrate reductase assay (NRA) is one of the colorimetric susceptibility test methods for rapid detection of MDR-TB and based on the ability of reduction of nitrate to nitrite by Mycobacterium tuberculosis. The aim of this study was to evaluate the performance of the NRA for the rapid detection of MDR-TB. A total of 237 M.tuberculosis complex (MTC) isolates that were identified by the same method (BD MGIT(TM) TBc Identification Test, USA) from nine different medical centers in Turkey were included in the study. The susceptibility results of the isolates against INH and RIF obtained by reference test (Bactec MGIT(TM) 960, BD, USA) were then compared with NRA. In order to ensure consistency between centers, Löwenstein-Jensen (LJ) medium with antibiotics and without antibiotics (growth control) and Griess reagent solution were prepared in a single center (Ondokuz Mayıs University School of Medicine, Medical Microbiology Department) and sent to all participant centers with the standardized test procedure. After the inoculation of bacteria into the test tubes, the tubes were incubated at 37°C, and after seven days of incubation, 500 μl Griess reagent was added to the LJ medium without antibiotics. If a color change was observed, an equal volume of Griess reagent was added to test LJ media with antibiotics. When a color change was observed in LJ media with antibiotics, it was considered that the isolate was resistant to tested antibiotics. Among 237 MTC isolates, 16 were resistant only to INH and nine were resistant only to RIF; 93 isolates (39.2%) were resistant (MDR) and 119 isolates (50.2%) were susceptible to both of the drugs determined with the reference susceptibility test. In the study, five INH-resistant isolates determined with reference method were found susceptible with NRT and eight INH-susceptible isolates determined with reference method were found resistant with NRT. In contrast, one RIF-resistant isolate determined with reference method was found susceptible with NRT and three RIF-susceptible determined isolates were found resistant with NRT. Accordingly, the concordance rate between the reference method and NRA were estimated as 94.5% for INH and 98.3% for RIF. The sensitivi

Topics: Antitubercular Agents; Colorimetry; Drug Resistance, Multiple, Bacterial; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Nitrate Reductase; Nitrates; Nitrites; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant; Turkey

Less than 30% of multidrug-resistant tuberculosis (MDR-TB) patients are currently diagnosed, due to laboratory constraints. Molecular diagnostics enable rapid and simplified diagnosis. Newer-version line probe assays have not been evaluated against the WHO-endorsed Hain GenoType MTBDRplus (referred to as Hain version 1 [V1]) for the rapid detection of rifampin (RIF) and isoniazid (INH) resistance. A two-phase noninferiority study was conducted in two supranational reference laboratories to allow head-to-head comparisons of two new tests, Hain Genotype MTBDRplus version 2 (referred to as Hain version 2 [V2]) and Nipro NTM+MDRTB detection kit 2 (referred to as Nipro), to Hain V1. In phase 1, the results for 379 test strains were compared to a composite reference standard that used phenotypic drug susceptibility testing (DST) and targeted sequencing. In phase 2, the results for 644 sputum samples were compared to a phenotypic DST reference standard alone. Using a challenging set of strains in phase 1, the values for sensitivity and specificity for Hain V1, Hain V2, and Nipro, respectively, were 90.3%/98.5%, 90.3%/98.5%, and 92.0%/98.5% for RIF resistance detection and 89.1%/99.4%, 89.1%/99.4%, and 89.6%/100.0% for INH resistance detection. Testing of sputa in phase 2 yielded values for sensitivity and specificity of 97.1%/97.1%, 98.2%/97.8%, and 96.5%/97.5% for RIF and 94.4%/96.4%, 95.4%/98.8%, and 94.9%/97.6% for INH. Overall, the rates of indeterminate results were low, but there was a higher rate of indeterminate results with Nipro than with Hain V1 and V2 in samples with low smear grades. Noninferiority of Hain V2 and Nipro to Hain V1 was demonstrated for RIF and INH resistance detection in isolates and sputum specimens. These results serve as evidence for WHO policy recommendations on the use of line probe assays, including the Hain V2 and Nipro assays, for MDR-TB detection.

Topics: Antitubercular Agents; Cross-Sectional Studies; Drug Resistance, Bacterial; Genotyping Techniques; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

The emergence and spread of drug-resistant tuberculosis (DR-TB) has become the major concern in global TB control nowadays due to its limited therapy options and high mortality. A comprehensive evaluation for the epidemiological trends of DR-TB in mainland China, of which TB incidences remain high, is essential but lacking. This study aimed to describe the trends of DR-TB overtime, especially multidrug-resistant TB (MDR-TB); and to identify unique characteristics of MDR-TB cases compared with drug-susceptible TB cases in Mainland China. We retrospectively analyzed surveillance data collected from 36 TB prevention and control institutions in Shandong Province, China over an 8-year period. Unique characteristics of MDR-TB were identified; Chi-square test for trends and linear regression were used to assess the changes in proportions of different resistance patterns overtime. The overall MDR rate was 6.2% in our sample population. There were no statistically significant changes in the percentage of drug-susceptible, isoniazid (INH) resistance, ethambutol (EMB) resistance, streptomycin (SM) resistance, and MDR TB during our study period except that the overall rifampin (RFP) resistance and rifampin monoresistance (RMR) increased at a yearly rate of 0.2% and 0.1%, respectively. Among those with known treatment histories, a higher MDR rate of 8.7% was observed, in which 53.9% were primary MDR-TB patients, and this rate was increasing at a yearly rate of 4.1% over our study period. MDR-TB patients were more likely to be female (odds ratio [OR], 1.23; 95% confidence interval [CI], 1.05-1.34), aged 25 to 44 years (OR, 1.67; 95%CI, 1.45-1.93), retreated (OR, 11.95; 95%CI, 9.68-14.76), having prior TB contact (OR, 1.89; 95%CI, 1.19-2.78) and having cavity (OR, 1.57; 95%CI 1.36-1.81), or bilateral disease (OR, 1.45; 95%CI 1.19-1.76) on chest radiology. Persistent high levels of MDR-TB, increasing rates of primary MDR-TB and RMR characterize DR-TB cases in mainland China; community-acquired drug resistance may be one of the most modifiable factors in future TB control strategies.

Topics: Adolescent; Adult; Aged; Antitubercular Agents; Child; Child, Preschool; China; Ethambutol; Female; Humans; Infant; Infant, Newborn; Isoniazid; Male; Middle Aged; Regression Analysis; Residence Characteristics; Retrospective Studies; Rifampin; Streptomycin; Tuberculosis, Multidrug-Resistant; Young Adult

Molecular diagnostic assays, with their ability to rapidly detect resistance-associated mutations in bacterial genes, are promising technologies to control the spread of drug-resistant tuberculosis (DR-TB). Sequencing assays provide detailed information for specific gene regions and can help diagnostic assay developers prioritize mutations for inclusion in their assays. We performed pyrosequencing of seven Mycobacterium tuberculosis gene regions (katG, inhA, ahpC, rpoB, gyrA, rrs, and eis) for 1,128 clinical specimens from India, Moldova, and South Africa. We determined the frequencies of each mutation among drug-resistant and -susceptible specimens based on phenotypic drug susceptibility testing results and examined mutation distributions by country. The most common mutation among isoniazid-resistant (INH(r)) specimens was the katG 315ACC mutation (87%). However, in the Eastern Cape, INH(r) specimens had a lower frequency of katG mutations (44%) and higher frequencies of inhA (47%) and ahpC (10%) promoter mutations. The most common mutation among rifampin-resistant (RIF(r)) specimens was the rpoB 531TTG mutation (80%). The mutation was common in RIF(r) specimens in Mumbai (83%) and Moldova (84%) but not the Eastern Cape (17%), where the 516GTC mutation appeared more frequently (57%). The most common mutation among fluoroquinolone-resistant specimens was the gyrA 94GGC mutation (44%). The rrs 1401G mutation was found in 84%, 84%, and 50% of amikacin-resistant, capreomycin-resistant, and kanamycin (KAN)-resistant (KAN(r)) specimens, respectively. The eis promoter mutation -12T was found in 26% of KAN(r) and 4% of KAN-susceptible (KAN(s)) specimens. Inclusion of the ahpC and eis promoter gene regions was critical for optimal test sensitivity for the detection of INH resistance in the Eastern Cape and KAN resistance in Moldova. (This study has been registered at ClinicalTrials.gov under registration number NCT02170441.).

Topics: Bacterial Proteins; Capreomycin; Drug Resistance, Multiple, Bacterial; Isoniazid; Kanamycin; Microbial Sensitivity Tests; Moldova; Mutation; Mycobacterium tuberculosis; Rifampin; South Africa; Tuberculosis; Tuberculosis, Multidrug-Resistant

New diagnostic methods have provided a promising solution for rapid and reliable detection of drug-resistant TB strains. The aim of this study was to evaluate the performance of the MeltPro TB assay in identifying multidrug-resistant (MDR-) and extensively drug-resistant tuberculosis (XDR-TB) patients from sputum samples. The MeltPro TB assay was evaluated using sputum samples from 2057 smear-positive TB patients. Phenotypic Mycobacterial Growth Indicator Tube (MGIT) 960 drug susceptibility testing served as a reference standard. The sensitivity of the MeltPro TB assay was 94.2% for detecting resistance to rifampicin and 84.9% for detecting resistance to isoniazid. For second-line drugs, the assay showed a sensitivity of 83.3% for ofloxacin resistance, 75.0% for amikacin resistance, and 63.5% for kanamycin resistance. However, there was a significant difference for detecting kanamycin resistance between the two pilot sites in sensitivity, which was 53.2% in Guangdong and 81.5% in Shandong (P = 0.015). Overall, the MeltPro TB assay demonstrated good performance for the detection of MDR- and XDR-TB, with a sensitivity of 86.7% and 71.4%, respectively. The MeltPro TB assay is an excellent alternative for the detection of MDR- and XDR-TB cases in China, with high accuracy, short testing turn-around time, and low unit price compared with other tests.

Topics: Amikacin; China; Extensively Drug-Resistant Tuberculosis; Humans; Kanamycin; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Ofloxacin; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant

To classify the prevalence of multi-drug resistant tuberculosis (MDR-TB) in two different geographic settings in western Kenya using the Lot Quality Assurance Sampling (LQAS) methodology.. The prevalence of drug resistance was classified among treatment-naïve smear positive TB patients in two settings, one rural and one urban. These regions were classified as having high or low prevalence of MDR-TB according to a static, two-way LQAS sampling plan selected to classify high resistance regions at greater than 5% resistance and low resistance regions at less than 1% resistance.. This study classified both the urban and rural settings as having low levels of TB drug resistance. Out of the 105 patients screened in each setting, two patients were diagnosed with MDR-TB in the urban setting and one patient was diagnosed with MDR-TB in the rural setting. An additional 27 patients were diagnosed with a variety of mono- and poly- resistant strains.. Further drug resistance surveillance using LQAS may help identify the levels and geographical distribution of drug resistance in Kenya and may have applications in other countries in the African Region facing similar resource constraints.

Topics: Adolescent; Adult; Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Female; Humans; Isoniazid; Kenya; Lot Quality Assurance Sampling; Male; Middle Aged; Mycobacterium tuberculosis; Prevalence; Rifampin; Rural Population; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Urban Population

Pre-extensively drug resistant (pre-XDR) and extensively drug resistant tuberculosis (XDR-TB) have been areas of growing concern, and are posing threat to global efforts of TB control. The present study was planned to study the presence of pre-XDR and XDR Mycobacterium tuberculosis and their genotypes in clinical isolates obtained from previously treated cases of pulmonary TB.. A total of 219 isolates obtained from previously treated cases of pulmonary TB were subjected to first-line (streptomycin, isoniazid, rifampicin and ethambutol) and second-line (ofloxacin, kanamycin, capreomycin and amikacin) drug susceptibility testing on solid Lowenstein-Jensen medium by proportion method. Genotyping was done for pre-XDR and XDR-TB isolates using 12 loci Mycobacterial Interspersed Repetitive Units-Variable Number Tandem Repeats (MIRU-VNTR).. Multi-drug resistance was observed in 39.7 per cent (87/219) isolates. pre-XDR and XDR M. tuberculosis isolates amongst 87 multi-drug resistant (MDR) TB isolates were 43 (49.4%) and 10 (11.4%), respectively. Two most dominant genotypes among pre-XDR and XDR M. tuberculosis isolates were Beijing and Delhi/CAS types.. Resistance to second-line anti-tubercular drugs should be routinely assessed in areas endemic for TB. Similar genotype patterns were seen in pre-XDR and XDR-TB isolates. Beijing and Delhi/CAS were predominant genotypes.

Topics: Drug Resistance, Multiple, Bacterial; Extensively Drug-Resistant Tuberculosis; Genotype; Humans; India; Isoniazid; Kanamycin; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Ofloxacin; Rifampin; Tuberculosis, Multidrug-Resistant

Tuberculosis remains an important cause of mortality worldwide. Previous tuberculosis treatment is a strong determinant of multi-drug resistant tuberculosis. The study objective was to describe the mutations detected of Mycobacterium tuberculosis (MTB) complex clinical strains screened with GeneXpert isolated from previously treated patients in Côte d'Ivoire.. Sputum collected and decontaminated by the n-acetyl-l-cysteine method was used to perform Ziehl-Neelsen staining, GeneXpert MTB/rifampicin, and culture on Lowenstein-Jensen medium. Drug susceptibility testing (DST) for first-line drugs was performed in a Bactec 960 Automated System. After strain identification by antigen MPT64 detection, DNA extraction, and genotyping with MTBDRplus assay was performed and interpreted. The strains muted in rpoB without a specific protein identified and were sequenced.. Mutant sequences were detected in 60 sputum samples with GeneXpert MTB/rifampicin of which 55 were confirmed multi-drug resistant MTB strains after DST. The most frequent mutations responsible for rifampin resistance were detected with MTBDRplus assay for 49 (81.7%) clinical strains, while sequencing was required for 11 (18.3%). H526Q mutation, L533P, and D516V associated respectively with L533P, A532A, and S522L, and were observed for three relapse cases. For these cases, GeneXpert and sequencing results were concordant. Discrepancies between GeneXpert and mycobacteria growth indicator tube-DST for rifampin were observed for three strains, on which D516Y, H526C, and L533P were identified.. In the setting of a high prevalence of drug resistance, characterization of the genetic basis of MTB strains resistant to rifampin could be screened first with MTBDRplus.

Topics: Adult; Antitubercular Agents; Bacterial Proteins; Cote d'Ivoire; Drug Resistance, Multiple, Bacterial; Female; Genotype; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Mutation; Mycobacterium tuberculosis; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Young Adult

The nature and frequency of mutations in rifampicin (RIF) and isoniazid (INH) resistant Mycobacterium tuberculosis isolates vary considerably according to geographic locations. However, information regarding specific mutational patterns in Ethiopia remains limited.. A cross-sectional prospective study was carried out among confirmed pulmonary tuberculosis cases in Southwest Ethiopia. Mutations associated with RIF and INH resistances were studied using GenoType MTBDRplus line probe assay in 112 M. tuberculosis isolates. Culture (MGIT960) and identification tests were performed at the Mycobacteriology Research Center of Jimma University, Jimma, Ethiopia.. Mutations conferring resistance to INH, RIF, and multidrug resistance were detected in 36.6% (41/112), 30.4% (34/112), and 27.7% (31/112) of M. tuberculosis isolates respectively. Among 34 RIF-resistant isolates, 82.4% (28/34) had rpoB gene mutations at S531L, 2.9% (1/34) at H526D, and 14.7% (5/34) had mutations only at wild type probes. Of 41 INH-resistant strains, 87.8% (36/41) had mutations in the katG gene at Ser315Thr1 and 9.8% (4/41) had mutations in the inhA gene at C15T. Mutations in inhA promoter region were strongly associated with INH monoresistance.. A high rate of drug resistance was commonly observed among failure cases. The most frequent gene mutations associated with the resistance to INH and RIF were observed in the codon 315 of the katG gene and codon 531 of the rpoB gene, respectively. Further studies on mutations in different geographic regions using DNA sequencing techniques are warranted to improve the kit by including more specific mutation probes in the kit.

Topics: Adolescent; Antitubercular Agents; Bacterial Proteins; Drug Resistance, Bacterial; Ethiopia; Female; Humans; Isoniazid; Middle Aged; Mutation; Mycobacterium tuberculosis; Prospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Drug-resistant strains of tuberculosis (TB) represent a major threat to global TB control. In low- and middle-income countries, resource constraints make it difficult to identify and monitor cases of resistance using drug susceptibility testing and culture. Molecular assays such as the GeneXpert Mycobacterium tuberculosis/rifampicin may prove to be a cost-effective solution to this problem in these settings. The objective of this study is to evaluate the use of GeneXpert in the diagnosis of pulmonary TB since it was introduced into two tertiary hospitals in Ghana in 2013.. A 2-year retrospective audit of clinical cases involving patients who presented with clinically suspected TB or documented TB not improving on standard therapy and had samples sent for GeneXpert testing.. GeneXpert identified 169 cases of TB, including 17 cases of rifampicin-resistant TB. Of the seven cases with final culture and drug susceptibility testing results, six demonstrated further drug resistance and five of these were multidrug-resistant TB.. These findings call for a scale-up of TB control in Ghana and provide evidence that the expansion of GeneXpert may be an optimal means to improve case finding and guide treatment of drug-resistant TB in this setting.

Topics: Antibiotics, Antitubercular; Drug Resistance, Bacterial; Female; Ghana; Humans; Male; Middle Aged; Mycobacterium tuberculosis; Prevalence; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant

The emergence of multidrug-resistant strains is a major health problem especially for countries with high TB incidence such as Peru. In this study, we evaluated High Resolution Melting (HRM) assay in Peruvian isolates for the detection of mutations within rpoB, katG genes and promoter region inhA to determine isoniazid and rifampicin resistance in Mycobacterium tuberculosis (Mtb).. DNA samples extracted from a total of 167 clinical isolates of Mtb, 89 drug-sensitive and 78 multidrug-resistant, were blindly analyzed by HRM analysis and verified by DNA sequencing.. The HRM analysis generated patterns that were specific to distinguish between sensitive and resistance isolates. The sensitivity and specificity of the HRM assays in comparison with drug susceptibility testing (DST) for detection of rifampicin resistance were 98.7 % and 97.5 %, and for isoniazid resistance were 98.7 % and 100 %.. This study suggests that HRM Analysis could help with rapid diagnosis of MDR-TB cases in Peru.

Topics: Antitubercular Agents; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Peru; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

In order to detect the in vitro synergistic effect of 4 drugs-pasiniazid (PA), moxifloxacin, rifabutin and rifapentini on multidrug-resistant mycobacterium tuberculosis (MDR-MTB) and extensively drug-resistant mycobacterium tuberculosis(XDR-MTB), which were core drugs of"The program of retreatment research of tuberculosis".. The checkerboard method was used to detect the minimum inhibitory concentration (MIC) of antituberculosis drug combination schemes (moxifloxacin-PA, moxifloxacin-PA-rifabutin and moxifloxacin-PA-rifapentini) to 40 strains of clinical drug resistant MTB(20 strains of MDR-MTB and 20 XDR-MTB) and the standard strain H37Rv, by calculating the fractional inhibitory concentration index of joint action in vitro to judge the combined effect, with fractional inhibitory concentration index(FICI)≤0.5 and FICI≤0.75 as the basis of 2 drugs and 3 drugs showing synergy.. The FICI of moxifloxacin-PA scheme for DR-MTB was 0.125 to 1.000, only 5 strains with a FICI ≤0.5, showing synergistic effect. The FICI of moxifloxacin-Pa-rifabutin scheme with 20 strains of MDR-MTB ranged from 0.310 to 1.260, 10 strains with a FICI≤0.75, showing synergistic effect. The FICI of moxifloxacin-PA-rifabutin scheme with 20 strains of XDR-MTB ranged from 0.215 to 1.250, 11 strains with a FICI≤0.75, showing synergistic effect. The FICI of moxifloxacin-PA-rifapentini scheme with 20 strains of MDR-MTB ranged from 0.150 to 0.780, 19 strains with a FICI≤0.75, showing synergistic effect. The FICI of moxifloxacin-PA-rifapentini scheme with 20 strains of XDR-MTB ranged from 0.200 to 1.280, 16 strains with a FICI≤0.75, showing synergistic effect.. The synergistic effect of moxifloxacin-PA scheme was poor, but showing better synergy when further combined with rifabutin or rifapentini. Rifabutin showed better effect than rifapentini, but the synergistic effect of moxifloxacin-PA-rifabutin combination scheme was poor than that of moxifloxacin-PA-rifapentini combination scheme.

Topics: Aminosalicylic Acids; Antibiotics, Antitubercular; Drug Synergism; Drug Therapy, Combination; Extensively Drug-Resistant Tuberculosis; Fluoroquinolones; Isoniazid; Microbial Sensitivity Tests; Moxifloxacin; Mycobacterium tuberculosis; Retreatment; Rifabutin; Rifampin; Tuberculosis, Multidrug-Resistant

Rapid and correct diagnosis is crucial for the management of multidrug resistance (MDR) in Mycobacterium tuberculosis (MTB). The present study aims at rapid diagnosis for identification of multidrug resistance tuberculosis (MDR-TB) using real-time PCR. FRET hybridization probes targeting most prominent four selected codons for rpoB526 and 531 and for katG314 and 315 genes were designed and evaluated on 143 clinical MTB isolates and paired sputa for rapid detection of MDR-TB. The results of real-time PCR were compared with gold standard L-J proportion method and further validated by DNA sequencing. Of the 143 MTB positive cultures, 85 and 58 isolates were found to be 'MDR' and 'pan susceptible', respectively by proportion L-J method. The sensitivity of real-time PCR for the detection of rifampicin (RIF) and isoniazid (INH) were 85.88 and 94.11%, respectively, and the specificity of method was found to be 98.27%. DNA sequencing of 31 MTB isolates having distinct melting temperature (Tm) as compared to the standard drug susceptible H37Rv strain showed 100% concordance with real-time PCR results. DNA sequencing revealed the mutations at Ser531Leu, His526Asp of rpoB gene and Ser315Thr, Thr314Pro of katG gene in RIF and INH resistance cases. This real-time PCR assay that targets limited number of loci in a selected range ensures direct and rapid detection of MDR-TB in Indian settings. However, future studies for revalidation as well as refinement are required to break the limitations of MDR-TB detection.

Topics: Antitubercular Agents; DNA, Bacterial; Fluorescence Resonance Energy Transfer; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Real-Time Polymerase Chain Reaction; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

In recent years, whole-cell-based screens for novel small molecule inhibitors active against Mycobacterium tuberculosis in culture followed by the whole-genome sequencing of spontaneous resistant mutants have identified multiple chemical scaffolds thought to kill the bacterium through the inactivation of the mycolic acid transporter, MmpL3. Consistent with the fact that MmpL3 is required for the formation of the mycobacterial outer membrane, we have conclusively shown in this study, using conditionally regulated knockdown mutants, that mmpL3 is required for the replication and viability of M. tuberculosis, both under standard laboratory growth conditions and during the acute and chronic phases of infection in mice. Speaking for the vulnerability of this target, silencing mmpL3 had a rapid bactericidal effect on actively replicating cells in vitro and reduced by 3 to 5 logs in less than 4 weeks the bacterial loads of acutely and chronically infected mouse lungs, respectively. Depletion of MmpL3 further rendered M. tuberculosis hypersusceptible to MmpL3 inhibitors. The exquisite vulnerability of MmpL3 at all stages of the infection establishes this transporter as an attractive new target with the potential to improve and shorten current drug-susceptible and drug-resistant tuberculosis chemotherapies.

Topics: Animals; Antitubercular Agents; Bacterial Load; Bacterial Proteins; Biological Transport; Ciprofloxacin; Disease Models, Animal; Doxycycline; Female; Gene Expression; Gene Knockdown Techniques; Humans; Isoniazid; Lung; Membrane Transport Proteins; Mice; Mice, Inbred C57BL; Microbial Sensitivity Tests; Microbial Viability; Mycobacterium tuberculosis; Mycolic Acids; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

In this study we evaluated the crystal violet decolorization assay (CVDA) for detection of minimum inhibitory concentration (MIC) of antituberculosis drugs. 53 isolates were tested in this study and 13 of them were multidrug resistant (MDR) isolates. The antibiotics concentrations were 2-0.06 mg/L for isoniazid (INH) and rifampicin (RIF) and were 16-0.25 mg/L for streptomycin (STM) and ethambutol (EMB). Crystal violet (CV-25 mg/L) was added into the microwells on the seventh day of incubation and incubation was continued until decolorization. Decolorization of CV was the predictor of bacterial growth. Overall agreements for four drugs were detected as 98.1%, and the average time was detected as 9.5 ± 0.89 day after inoculation. One isolate for INH and two isolates for STM were determined resistant in the reference method, but susceptible by the CVDA. One isolate was susceptible to EMB by the reference method, but resistant by the CVDA. All results were concordant for RIF. This study shows that CVDA is a rapid, reliable and suitable for determination of MIC values of Mycobacterium tuberculosis. And it can be used easily especially in countries with limited-sources.

Topics: Antitubercular Agents; Biological Assay; Drug Resistance, Multiple, Bacterial; Ethambutol; Gentian Violet; Humans; Indicators and Reagents; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Streptomycin; Tuberculosis, Multidrug-Resistant

Topics: Biopsy; Humans; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Pyrazinamide and fluoroquinolones are essential antituberculosis drugs in new rifampicin-sparing regimens. However, little information about the extent of resistance to these drugs at the population level is available.. In a molecular epidemiology analysis, we used population-based surveys from Azerbaijan, Bangladesh, Belarus, Pakistan, and South Africa to investigate resistance to pyrazinamide and fluoroquinolones among patients with tuberculosis. Resistance to pyrazinamide was assessed by gene sequencing with the detection of resistance-conferring mutations in the pncA gene, and susceptibility testing to fluoroquinolones was conducted using the MGIT system.. Pyrazinamide resistance was assessed in 4972 patients. Levels of resistance varied substantially in the surveyed settings (3·0-42·1%). In all settings, pyrazinamide resistance was significantly associated with rifampicin resistance. Among 5015 patients who underwent susceptibility testing to fluoroquinolones, proportions of resistance ranged from 1·0-16·6% for ofloxacin, to 0·5-12·4% for levofloxacin, and 0·9-14·6% for moxifloxacin when tested at 0·5 μg/mL. High levels of ofloxacin resistance were detected in Pakistan. Resistance to moxifloxacin and gatifloxacin when tested at 2 μg/mL was low in all countries.. Although pyrazinamide resistance was significantly associated with rifampicin resistance, this drug may still be effective in 19-63% of patients with rifampicin-resistant tuberculosis. Even though the high level of resistance to ofloxacin found in Pakistan is worrisome because it might be the expression of extensive and unregulated use of fluoroquinolones in some parts of Asia, the negligible levels of resistance to fourth-generation fluoroquinolones documented in all survey sites is an encouraging finding. Rational use of this class of antibiotics should therefore be ensured to preserve its effectiveness.. Bill & Melinda Gates Foundation, United States Agency for International Development, Global Alliance for Tuberculosis Drug Development.

Topics: Anti-Infective Agents; Antitubercular Agents; Asia; Fluoroquinolones; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Population Surveillance; Pyrazinamide; Retrospective Studies; Rifampin; South Africa; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Multidrug-resistant tuberculosis (MDR-TB) drugs which is resistant to the major first-line anti-TB drugs, Isoniazid and Rifampicin, has become a major global challenge in tuberculosis (TB) control programme. However, its burden at community level is not well known. Thus, the aim of study was to assess the prevalence of primary and secondary resistance to any first line anti-TB drugs and MDR TB in Hitossa District of Oromia Regional State, Central Ethiopia.. Population based cross- sectional study was conducted on individuals aged ≥15 years. Those with symptoms suggestive of TB were interviewed and two sputum specimens were collected from each and examined using Lowenstein-Jensen (LJ) culture medium. Further, the isolates were confirmed by the Ziehl-Neelsen microscopic examination method. Drug susceptibility test (DST) was also conducted on LJ medium using a simplified indirect proportion method. The resistance strains were then determined by percentage of colonies that grew on the critical concentration of Isoniazid, Streptomycin, Rifampicin and Ethambutol.. The overall resistance of all forms of TB to any first-line anti-TB drug was 21.7 %. Of the total new and previously treated culture positive TB cases, 15.3 and 48.8 % respectively were found to be a resistant to any of the first-line anti-TB drugs. Further, of all forms of TB, the overall resistance of MDR-TB was 4.7 %. However, of the total new TB cases, 2.4 % had primary while 14.3 % had secondary MDR-TB. Resistance to any of the first-line anti-TB drugs (adjusted odd ratio (AOR), 8.1; 95 % CI: 2.26-29.30) and MDR-TB (AOR), 7.1; 95 % CI: 2.6-43.8) was found to be linked with previous history of anti-TB treatment.. The study has identified a high rate of primary and secondary resistance to any of the first-line anti-TB drugs and MDR-TB in the study area. The resistance may have resulted from sub-optimal performance of directly observed treatment short-course (DOTS) programme in the detecting infectious TB cases and cure rates in the study area. Anti-TB drug resistance is linked with previous TB treatment. There is a need to strengthen DOTS and DOTS-Plus programmes and expand MDR-TB diagnostic facilities in order to timely diagnose MDR-TB cases and provide appropriate treatment to prevent the spread of MDR-TB in Ethiopia.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antitubercular Agents; Drug Resistance, Bacterial; Ethambutol; Ethiopia; Female; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Odds Ratio; Prevalence; Rifampin; Streptomycin; Tuberculosis, Multidrug-Resistant; Young Adult

To analyze the drug-resistance of clinical Mycobacterium tuberculosis strains isolated from the tuberculosis(TB)patients in six provinces in China and related risk factors, and provide evidences for the effective prevention and treatment of drug resistant TB.. Six provinces were selected from China. The background information of the TB patients was investigated with questionnaire survey, and the drug susceptibilities of the clinical M. tuberculosis strains to isoniazid, rifampin, ethambutol and streptomycin were tested by means of the proportional drug susceptibility test. Then the results and related risk factors were analyzed with software SPSS 20.0.. The overall drug resistant rate and multi drug-resistant(MDR)rate were 23.42% and 13.51% respectively. The overall drug resistant rate and MDR rate in Beijing, Jilin, Hunan, Henan, Shaanxi, Xinjiang were 21.50%, 12.24%, 36.27%, 42.86%, 27.78%, 24.39% and 4.67%, 8.16%, 24.51%, 26.53%, 15.28%, 14.15%, respectively. The χ(2) analysis results showed that the differences in single drug-resistant rate, overall drug resistant rate and MDR rate in these provinces had significant differences(P=0.000). The univariate statistical analysis results showed that the retreatment for TB and TB treatment history were the risk factors associated with drug resistance(P<0.05).. The drug resistance of TB was very serious in China, but the TB drug resistance varied with province. The preventive intervention should be strengthened against all the major risk factors associated with the drug resistance for the better prevention and control of TB.

Topics: Antitubercular Agents; China; Drug Resistance, Multiple, Bacterial; Ethambutol; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Prevalence; Rifampin; Risk Factors; Streptomycin; Surveys and Questionnaires; Tuberculosis, Multidrug-Resistant

Initial cost-effectiveness evaluations of Xpert(®) MTB/RIF for tuberculosis (TB) diagnosis have not fully accounted for the realities of implementation in peripheral settings.. To evaluate costs and diagnostic outcomes of Xpert testing implemented at various health care levels in Uganda.. We collected empirical cost data from five health centers utilizing Xpert for TB diagnosis, using an ingredients approach. We reviewed laboratory and patient records to assess outcomes at these sites and10 sites without Xpert. We also estimated incremental cost-effectiveness of Xpert testing; our primary outcome was the incremental cost of Xpert testing per newly detected TB case.. The mean unit cost of an Xpert test was US$21 based on a mean monthly volume of 54 tests per site, although unit cost varied widely (US$16-58) and was primarily determined by testing volume. Total diagnostic costs were 2.4-fold higher in Xpert clinics than in non-Xpert clinics; however, Xpert only increased diagnoses by 12%. The diagnostic costs of Xpert averaged US$119 per newly detected TB case, but were as high as US$885 at the center with the lowest volume of tests.. Xpert testing can detect TB cases at reasonable cost, but may double diagnostic budgets for relatively small gains, with cost-effectiveness deteriorating with lower testing volumes.

Topics: Antitubercular Agents; Cost-Benefit Analysis; Diagnostic Tests, Routine; Drug Resistance, Multiple, Bacterial; Empirical Research; Humans; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Uganda; Uncertainty

Longer-term tuberculosis (TB) drug resistance surveillance among children is rare. We determined the prevalence of drug resistance among children with culture-confirmed TB from 2011 to 2013, compared these results with four previous consecutive 2-year periods and documented other mycobacterial isolates identified.. Surveillance study of mycobacterial culture in all children aged <13 years conducted from March 2011 to February 2013 at the Tygerberg Children's Hospital, Cape Town, South Africa. Drug susceptibility testing against isoniazid (INH) and rifampicin (RMP) was performed using line-probe assay (GenoType(®) MTBDRplus). Clinical data were obtained through folder review.. Of 381 children, 323 (84.8%; 324 episodes) had Mycobacterium tuberculosis, 46 (12.1%) had M. bovis bacille Calmette-Guérin and 12 (3.1%) had non-tuberculous mycobacteria isolated. Forty-one (12.7%) children had M. tuberculosis resistant to INH and/or RMP; 15 (4.7%) had multidrug-resistant TB (MDR-TB). The prevalence of INH mono- or polyresistance remained stable; however, RMP monoresistance increased (0/313 in 2003-2005 vs. 6/324, 1.9%, in 2011-2013; P = 0.041); MDR-TB prevalence has declined significantly, from 26/292 (8.9%) in 2007-2009 to 15/324 (4.7%) in 2011-2013 (OR 0.50, 95%CI 0.24-0.99). The prevalence of human immunodeficiency virus co-infection has decreased significantly, from a peak of 29% to 15.3%.. There has been a significant reduction in bacteriologically confirmed MDR-TB cases. The increase in RMP monoresistance has important implications for treatment.

Topics: Anti-Retroviral Agents; Antitubercular Agents; Child; Child, Preschool; Coinfection; Epidemiological Monitoring; Female; HIV Infections; Humans; Infant; Isoniazid; Male; Mycobacterium bovis; Mycobacterium tuberculosis; Nontuberculous Mycobacteria; Prevalence; Rifampin; South Africa; Tuberculosis, Multidrug-Resistant

The aim of this study was to determine the risk factors for multidrug-resistant tuberculosis (TB) in the city of Kinshasa in the Democratic Republic of Congo.. This was a case control study. The cases included all TB patients notified as resistant to rifampicin and isoniazid in Kinshasa from January 2012 to June 2013. The controls included TB patients treated during the same period as the cases and declared cured at the end of treatment. For this study, we obtained ethical clearance.. The sample consisted of 213 participants, 132 men (62%) and 81 women (38%). The median age was 31 years (16-73 years). Factors associated with significant (p< 0,05) multidrug-resistant tuberculosis were the non-observance of the hours of taking drugs (0R = 111) (80% cases, 4% controls), the failure of treatment (0R = 20 (76% cases, 13% controls); the concept of multidrug-resistant tuberculosis in the family (0R = 6.4) (28% cases, 6% controls); a lack of knowledge of multidrug-resistant tuberculosis (0R = 3.2) (31% cases, 59% controls); a stay in prison (0R = 7.6) (10% cases, 1% controls) and the interruption of treatment (0R = 6.1) (59% cases, 19% controls).. The emergence of multidrug-resistant tuberculosis can be avoided by the installation of suitable diagnosis and treatment strategies.

Topics: Adolescent; Adult; Aged; Antitubercular Agents; Case-Control Studies; Democratic Republic of the Congo; Female; Humans; Isoniazid; Male; Middle Aged; Rifampin; Risk Factors; Tuberculosis, Multidrug-Resistant; Young Adult

Multi-drug resistant tuberculosis (MDR-TB) is a major public health problem especially in developing countries. World Health Organization (WHO) recommends use of Xpert MTB/RIF assay to simultaneously detecting Mycobacterium tuberculosis (MTB) and rifampicin (RIF) resistance. The primary objective of this study was to determine the frequency of MDR-TB in patients suspected to have drug resistance in Khyber Pakhtunkhwa. The frequency of probes for various rpoB gene mutations using Xpert MTB/RIF assay within 81 bp RRDR (Rifampicin Resistance Determining Region) was the secondary objective.. A total of 2391 specimens, received at Programmatic Management of Drug Resistant TB (PMDT) Unit, Lady Reading Hospital (LRH) Peshawar, Pakistan, between October 2011 and December 2014, were analyzed by Xpert MTB/RIF test. MTB positive with rifampicin resistance were further analyzed to first line anti-mycobacterial drug susceptibility testing (DST) using middle brook 7H10 medium. The data was analyzed using statistical software; SPSS version 18.. Out of 2391 specimens, 1408 (59 %) were found positive for MTB and among them, 408 (29 %) showed rifampicin-resistance with four different rpoB gene mutations within 81 bp RRDR. The frequency of various probes among RIF-resistant isolates was observed as: probe E, in 314 out of 408 isolates; B, 44 out of 408; A, 5 out of 408; D, 34 out of 408; and probe C was observed among 6 out of 408 RIF-resistant isolates. The probe A&B and E&D mutation combination was found in only 1 isolate in each case, while B&D mutation combination was detected among 3 out of 408 RIF-resistant isolates.. Hence, it is concluded from our study on a selected population, 29 % of patients had MDR-TB. Probe E related mutations (also known as codon 531and 533) were the most common rpoB genetic mutation [314 (77 %)], acknowledged by Xpert MTB/RIF assay. Least mutation was detected within the sequence 511 (1.2 %).

Topics: Adolescent; Adult; Bacterial Proteins; DNA-Directed RNA Polymerases; Drug Resistance, Bacterial; Female; Humans; Male; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Pakistan; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant; Young Adult

Genotypic molecular testing may be very helpful for tuberculosis (TB) drug-resistance surveillance and for treatment guidance in low resource settings.. Descriptive analysis of M. tuberculosis isolates from Beira Central Hospital, Mozambique, during 2014-2015. Genotype MTBDRplus and MTBDRsl were used and patient medical records reviewed. To explore genotypic susceptibility profile of Mycobacterium tuberculosis, to first and second line drugs (SLD) in Beira Mozambique.. Of 155 isolates, 16.1 % (25) were multidrug resistant (MDR), 8.4 % (13) isoniazid-monoresistant and 1.3 % (2) rifampicin-monoresistant. Among MDR-TB, 22.2 % showed primary and 77.8 % represented acquired resistance. The majority of patients with drug resistance had a history of previous TB treatment. Among 125 isolates tested for ethambutol and SLD, 7.2 % (9) were resistant to ethambutol, 4.8 % (6) to fluoroquinolones and 0.8 % (1) to ethambutol and fluoroquinolones. Resistance to injectable SLD was not detected.. As far as we know this is the first report of a genotypic testing used to provide information about SLD resistance in Mozambique, where phenotypic susceptibility testing is usually unavailable. Extensively drug resistant TB was not detected in this isolates from Beira Mozambique.

Topics: Adult; Antitubercular Agents; Drug Resistance, Bacterial; Ethambutol; Extensively Drug-Resistant Tuberculosis; Female; Fluoroquinolones; Genotype; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Mozambique; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Tuberculosis (TB) remains one of the globe's deadliest communicable diseases. The homeless individuals are at high risk to acquire TB and multi-drug resistant TB (MDR-TB), because of their poor living conditions and risky behaviors. Tuberculosis and MDR-TB in the homeless individuals can pose a risk to entire communities. However, the magnitude of the problem is not known in Ethiopia. Therefore, the aim of this study was to determine the prevalence and associated factors of smear positive pulmonary TB (PTB) and MDR-TB among homeless individuals in Dessie and Debre Birhan towns, Northeast Ethiopia.. A community based cross-sectional study design was conducted from September 2014 to June 2015. Using an active screening with cough of ≥2 weeks, 351 TB suspects homeless individuals were participated in this study. Data were collected by using pre-tested and structured questionnaire. Spot-morning-spot sputum sample was collected and examined for acid-fast bacilli (AFB) using fluorescence microscopy by Auramine O staining technique. All AFB positive sputum was further analyzed by GeneXpert for detection of Mycobacterium tuberculosis complex and rifampicin resistant gene. Univariate and multivariate logistic regressions were applied to identify factors associated with smear positive PTB and P value <0.05 was considered as statistically significant.. The prevalence of smear positive PTB was 2.6 % (95 % CI 1.3-5) among TB suspect homeless individuals. Extrapolation of this study finding implies that there were 505 smear positive PTB per 100,000 homeless individuals. All smear positive PTB sputum specimens were further analyzed by GeneXpert assay, the assay confirmed that all were positive for MTBC but none were resistant to RIF or MDR. Smoking cigarette regularly for greater than 5 years (AOR 10.1, 95 % CI 1.1, 97.7), body mass index lower than 18.5 (AOR 6.9, 95 % CI 1.12, 41.1) and HIV infection (AOR 6.8, 95 % CI 1.1, 40.1) were significantly associated with smear positive PTB.. The prevalence of smear positive PTB among TB suspect homeless individuals was 2.6 %. Among smear positive PTB, prevalence of HIV co-infection was very high 5 (55.5 %). Smoking cigarette regularly for greater than 5 years, BMI lower than 18.5 and HIV infection were factors associated with smear positive PTB. Special emphasis is needed for homeless individuals to exert intensive effort to identify undetected TB cases to limit the circulation of the disease into the community.

Topics: Adolescent; Adult; Antitubercular Agents; Body Mass Index; Coinfection; Cough; Cross-Sectional Studies; Ethiopia; Female; HIV; HIV Infections; Humans; Ill-Housed Persons; Male; Middle Aged; Mycobacterium tuberculosis; Prevalence; Rifampin; Risk Factors; Smoking; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

The objectives of this study were to evaluate the interactions between linezolid (LZD) and second-line anti-tuberculosis (TB) agents in susceptible and multidrug-resistant (MDR) TB in vitro, and to validate the in vitro results in a murine TB model.. The minimum inhibitory concentrations of LZD and seven second-line anti-TB drugs against H37Rv and three multidrug-resistant clinical isolates were determined by Alamar Blue assay, and the interaction patterns of LZD and the seven second-line anti-TB agents against the four isolates were studied using a dynamic checkerboard method. The activities of these combinations against Mycobacterium tuberculosis were evaluated in a murine model of TB.. The combination of LZD + capreomycin exhibited partial synergism for three of four isolates, LZD + para-aminosalicylic acid exhibited partial synergism for two of four isolates, and LZD + levofloxacin and LZD + amikacin exhibited partial synergism for one of four isolates; all other combinations showed indifference or an additive effect in vitro. The activities of six combinations and the standard regimen rifampicin + isoniazid + pyrazinamide were investigated in a murine model of TB (infection with H37Rv). Significant reductions in colony-forming units (CFU) were found in LZD + capreomycin and LZD + clofazimine groups when the CFU in the lungs on day 0 (the day of beginning treatment) was compared with the CFU in the lungs after 2 months of treatment.. These combinations of LZD and second-line anti-TB drugs were all active against MDR-TB with indifference or an additive effect, except LZD + capreomycin, which showed partial synergy.

Topics: Aminosalicylic Acid; Animals; Antitubercular Agents; Capreomycin; Drug Combinations; Drug Interactions; Humans; Isoniazid; Linezolid; Male; Mice, Inbred BALB C; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Pyrazinamide; Rifampin; Tuberculosis, Multidrug-Resistant

Tuberculosis continues to be a global public health problem, the extrapulmonary form being estimated to occur in 10-20% of immunocompetent individuals, increasing in patients who are carriers of the human immunodeficiency virus (HIV); its diagnosis is difficult with conventional methods due to the paucibacillary nature of samples. The Xpert® MTB/RIF test represents an important development in the molecular detection of Mycobacterium tuberculosis and has been used with a variety of non-respiratory clinical samples. . To determine the effectiveness of Xpert® MTB/RIF in the detection of M. tuberculosis and sensitivity to rifampicin in patients with suspected extrapulmonary tuberculosis attending Hospital Universitario de San Vicente Fundación in Medellín in 2013-2014. . This was a descriptive, cross-sectional ambispective study of 372 consecutive samples from 301 patients with suspected extrapulmonary tuberculosis, who were subjected to bacilloscopy, followed by culture in Ogawa Kudoh and the Xpert® MTB/RIF molecular test. . The most frequent base diagnosis (60%) for the 182 patients was infection with HIV. Using the culture as reference, the sensitivity and general specificity of the molecular test was 94% (95% CI: 83-100) and 97% (95% CI: 95-99), respectively; for bacilloscopy it was 38.71(95% CI: 19-57) and 100% (95% CI: 99-100), respectively. Sensitivities higher than 75% were found in analyses stratified by samples. Thirty-seven of the isolates were sensitive and one resistant to rifampicin. . Xpert® MTB/RIF performed well in samples from different tissues and liquids, representing a significant advance in support of extrapulmonary tuberculosis diagnosis in terms of time and percentage positivity.

Topics: Antibiotics, Antitubercular; Cross-Sectional Studies; HIV Infections; Humans; Mycobacterium tuberculosis; Real-Time Polymerase Chain Reaction; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Topics: Adult; Amikacin; Aminosalicylic Acid; Anti-Bacterial Agents; Antitubercular Agents; Bronchoscopy; Clofazimine; Depression; Drug Costs; Emigrants and Immigrants; Ethambutol; Extensively Drug-Resistant Tuberculosis; Fluoroquinolones; Health Care Costs; Humans; India; Isoniazid; Linezolid; Male; Mediastinum; Microbial Sensitivity Tests; Moxifloxacin; New Zealand; Pyrazinamide; Radiography, Thoracic; Rifampin; Schizophrenia, Paranoid; Tuberculosis, Lymph Node; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pleural; Tuberculosis, Pulmonary

Topics: Antitubercular Agents; Humans; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Objective To determine the use and performance of a line probe assay (LPA) compared with conventional culture and drug sensitivity testing (CDST) in patients registered with tuberculosis (TB) under routine program conditions in Peru in 2011-2013. Methods This was a descriptive, operational research, cross-sectional study of sputum specimens from patients with smear-positive pulmonary TB and mycobacterial cultures from patients with smear-negative or positive TB. Drug resistance to rifampicin and/or isoniazid detected by LPA was compared to CDST. Sensitivity, specificity, and predictive values were calculated and reliability for detecting drug resistance was assessed through kappa coefficient, with values 0.61-0.80 showing substantial correlation, and 0.81 or above showing almost-perfect correlation. Results In 2011-2013, there were 16 169 LPA tests performed, with the proportion of TB patients receiving the test increasing from 3.2% to 30.2%. In all, 2 905 LPA test results were compared to CDST. For LPA in sputum specimens, sensitivity for rifampicin was 92%; isoniazid, 94%; and MDR-TB, 88%; while specificity for rifampicin was 92%; isoniazid, 92%; and MDR-TB, 95%. For LPA in mycobacterial cultures, sensitivity for rifampicin was 95%; isoniazid, 96%; and MDR-TB, 90%; while specificity for rifampicin was 85%; isoniazid, 91%; and MDR-TB, 94%. Kappa coefficients were at 0.81 or above for all comparisons of LPA with CDST using sputum specimens and cultures, except for isoniazid in cultures, which was at 0.79. Conclusions This study suggests that LPA is a reliable and rapid screening test for drug-resistant TB and should be considered suitable for routine use and scale up in Peru.

Topics: Antitubercular Agents; Cross-Sectional Studies; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Peru; Reproducibility of Results; Rifampin; Sputum; Tuberculosis; Tuberculosis, Multidrug-Resistant

According to the World Health Organization, South Africa ranks as one of the highest burden of TB, TB/HIV co-infection, and drug-resistant TB (DR-TB) countries. DR-TB treatment is complicated to administer and relies on the use of multiple toxic drugs, with potential for severe adverse drug reactions. We report the occurrence of adverse events (AEs) during a standardised DR-TB treatment regimen at two outpatient, decentralized, public-sector sites in Johannesburg, South Africa.. We reviewed medical records of the six-month intensive treatment phase for rifampicin-resistant (RR) TB patients registered May 2012 - December 2014. Patients contributed follow-up time until death, loss from treatment, censoring (6 months) or data extraction. A standardized regimen of kanamycin, moxifloxacin, ethionamide, terizidone, and pyrazinamide was used according to national guidelines. AEs were graded using the AIDS Clinical Trial Group scale. We present subhazard ratios from competing risk analysis for time to severe AE, accounting for mortality and loss from treatment.. Across the two sites, 578 eligible patient files were reviewed. 36.7 % were categorized as low weight (≤50 kg) at DR-TB initiation. 76.0 % had no history of TB treatment prior to the current episode of RR TB. 26.8 % were diagnosed with RR TB while hospitalized, indicating poor clinical condition. 82.5 % of patients were also HIV positive, of whom 43.8 % were on ART prior to RR TB treatment and 32.1 % initiated ART with or after RR TB treatment. Median CD4 count was 114.5 (IQR: 45-246.5). Overall, 578 reports of AEs were captured for 204 patients (35.3 %) and 110 patients (19.0 %) had at least one severe AE reported. Patients with at least one AE experienced a median of 3 (IQR: 2-4) AEs per patient. HIV-positive patients with CD4 counts ≤100 cells/mm. Severe AE are common during the first 6 months of RR TB treatment and HIV-positive patients newly initiating ART have the highest subdistribution hazard ratio for severe AE, accounting for the competing risks of death and loss from treatment.

Topics: Adolescent; Adult; Anti-HIV Agents; Antitubercular Agents; CD4 Lymphocyte Count; Child; Cohort Studies; Coinfection; Female; HIV Infections; Humans; Male; Middle Aged; Retrospective Studies; Rifampin; South Africa; Tuberculosis; Tuberculosis, Multidrug-Resistant; Young Adult

Isoniazid-resistant rifampicin-susceptible (H. To characterise the clinical presentation, treatment, and clinical and microbiological outcomes among children with culture-confirmed H. Retrospective hospital-based cohort study.. Of the 72 children included in the study, the median age was 50.1 months (IQR 21.5-102.5); 42% were male. Forty-four (51%) had a potential source case; only 13 were confirmed H. Although overall outcomes were good, prolonged culture positivity and cases of treatment failure emphasise the need for additional attention to the management of children with H

Topics: Antitubercular Agents; Child; Child, Preschool; Drug Resistance, Multiple, Bacterial; Female; Follow-Up Studies; HIV Infections; Humans; Infant; Isoniazid; Male; Retrospective Studies; Rifampin; Risk Factors; South Africa; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Estimates of the tuberculosis (TB) burden in the Philippines are largely dependent on prevalence surveys.. To conduct a prospective community-based survey to generate epidemiological data on TB among patients seeking care in public health centres in a rural municipality in the Philippines.. Prospective surveillance and follow-up of presumptive TB cases from May 2013 to July 2015.. Of 1622 participants with presumptive TB, 468 (28.8%) (95%CI 26.6-31.1) were diagnosed with TB. The annual TB case notification rate in San Juan was 212 (95%CI 184-242) per 100 000 population. There were nine TB-attributable deaths during the study period. Only 8.8% (95%CI 6.2-11.32) of the cases were children aged <15 years; 274 (58.5%) cases were bacteriologically confirmed. Of 210 isolates tested for antimicrobial resistance, 49 (23.3%, 95%CI 17.58-29.02) were resistant. Resistance to isoniazid (INH) was common (n = 33, 15.7%); multidrug-resistant TB was 1.9%.. TB remains an important health problem in the Philippines. We identified low case detection of TB in children and high INH resistance rates in this rural community.

Topics: Adolescent; Adult; Aged; Antitubercular Agents; Child; Child, Preschool; Female; Follow-Up Studies; Humans; Infant; Infant, Newborn; Isoniazid; Kanamycin; Male; Middle Aged; Philippines; Population Surveillance; Prevalence; Prospective Studies; Public Health; Rifampin; Rural Population; Streptomycin; Treatment Outcome; Tuberculosis; Tuberculosis, Multidrug-Resistant; Young Adult

In South Africa, drug resistant tuberculosis is a major public health crisis in the face of the colossal HIV pandemic.. In an attempt to understand the distribution of drug resistance in our setting, we analysed the rpoB, katG, inhA, pncA and embB genes associated with resistance to key drugs used in the treatment of tuberculosis in clinical isolates of Mycobacterium tuberculosis in the KwaZulu-Natal province.. Classical mutations were detected in the katG, inhA and embB genes associated with resistance to isoniazid and ethambutol. Diverse mutations were recorded in the multidrug resistant (MDR) and extensively drug resistant (XDR) isolates for the rpoB and pncA gene associated with resistance to rifampicin and pyrazinamide.. M.tuberculosis strains circulating in our setting display a combination of previously observed mutations, each mediating resistance to a different drug. The MDR and XDR TB isolates analysed in this study displayed classical mutations linked to INH and EMB resistance, whilst diverse mutations were linked to RIF and PZA resistance. The similarity of the XDR strains confirms reports of the clonality of the XDR epidemic. The successful dissemination of the drug resistant strains in the province underscores the need for rapid diagnostics to effectively diagnose drug resistance and guide treatment.

Topics: Amidohydrolases; Antitubercular Agents; Bacterial Proteins; Catalase; Drug Resistance, Multiple, Bacterial; Ethambutol; Extensively Drug-Resistant Tuberculosis; Humans; Isoniazid; Mutation; Mycobacterium tuberculosis; Oxidoreductases; Pentosyltransferases; Polymorphism, Restriction Fragment Length; Pyrazinamide; Rifampin; South Africa; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Drug Resistance, Bacterial; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Topics: Adult; Antitubercular Agents; Bacterial Proteins; Catalase; DNA-Directed RNA Polymerases; Drug Resistance, Multiple, Bacterial; Ethambutol; Female; Gene Expression; Genome, Bacterial; Humans; Isoniazid; Male; Middle Aged; Mutation; Myanmar; Mycobacterium tuberculosis; Recurrence; Rifampin; Sputum; Streptomycin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Whole Genome Sequencing

Only a few studies done earlier in India reveal the utility of real-time PCR in detecting drug resistance in cases of pulmonary tuberculosis.. The study was carried out to standardise real-time PCR (Quantitative real-time PCR, qPCR) targeting 16s RNA for the rapid detection of tuberculosis and its drug resistance from suspected TB patients.. Sputum samples from 100 clinically suspected tuberculosis patients, after processing were subjected to microscopy, MGIT culture and qPCR. qPCR targeted 16sRNA for detecting Mycobacterium tuberculosis complex, KatG and rpoB genes for detection of resistance to isoniazid and rifampicin respectively. 1% proportionate method and Line probe assay (Hain Lifesciences, Nehren, Germany) were used to confirm the MDR isolates.. The study showed positivity of microscopy, culture and qPCR for M. tuberculosis as 37%, 44% and 46% respectively. Sensitivity of 100% and specificity of 96.5% in the detection of M. tuberculosis was observed for qPCR in comparison to culture. MDRTB was detected in 14 cases whereas monoresistance to rifampicin and isoniazid was detected in 1 and 3 samples respectively.. Real-time PCR targeting 16sRNA, KatG and rpoB is a sensitive, specific, rapid and reliable technique to detect pulmonary tuberculosis and its MDR status directly from the sputum samples.

Topics: Antitubercular Agents; DNA, Bacterial; Drug Resistance; Drug Resistance, Multiple, Bacterial; Humans; India; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Real-Time Polymerase Chain Reaction; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant

Clinical management of drug-resistant tuberculosis patients continues to present significant challenges to global health. To tackle these challenges, the Abbott RealTime MTB RIF/INH Resistance assay was developed to accelerate the diagnosis of rifampicin and/or isoniazid resistant tuberculosis to within a day. This article summarizes the performance of the Abbott RealTime MTB RIF/INH Resistance assay; including reliability, analytical sensitivity, and clinical sensitivity/specificity as compared to Cepheid GeneXpert MTB/RIF version 1.0 and Hain MTBDRplus version 2.0. The limit of detection (LOD) of the Abbott RealTime MTB RIF/INH Resistance assay was determined to be 32 colony forming units/milliliter (cfu/mL) using the Mycobacterium tuberculosis (MTB) strain H37Rv cell line. For rifampicin resistance detection, the Abbott RealTime MTB RIF/INH Resistance assay demonstrated statistically equivalent clinical sensitivity and specificity as compared to Cepheid GeneXpert MTB/RIF. For isoniazid resistance detection, the assay demonstrated statistically equivalent clinical sensitivity and specificity as compared to Hain MTBDRplus. The performance data presented herein demonstrate that the Abbott RealTime MTB RIF/INH Resistance assay is a sensitive, robust, and reliable test for realtime simultaneous detection of first line anti-tuberculosis antibiotics rifampicin and isoniazid in patient specimens.

Topics: Antitubercular Agents; Colony Count, Microbial; Drug Resistance, Multiple, Bacterial; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Specimen Handling; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Sputum culture conversion in pulmonary multidrug-resistant tuberculosis (MDR-TB) is important to make treatment-related decisions and prevent transmission of disease.. To identify factors associated with sputum culture conversion, and to determine time to culture conversion and the impact of culture conversion on successful treatment outcomes in MDR-/rifampicin (RMP) resistant TB.. Retrospective analysis of data from treatment cards and registers of MDR-/RMP-resistant patients initiated on treatment under India's Revised National TB Control Programme in Delhi, West Bengal and Kerala from January 2009 to December 2011. Proportions were calculated and logistic regression analysis was performed.. Of 836 patients, 787 were analysed, 651 (83%) of whom experienced culture conversion: respectively 57%, 73% and 79% culture converted by month 3, 4 and 6 of treatment. The median time to culture conversion was 91.3 days. Patients with body mass index (BMI) 16 kg/m2 (OR 0.403, P = 0.001) and 1618 kg/m2 (OR 0.519, P = 0.039) were less likely to have culture conversion. High rates of culture conversion were observed in patients with successful treatment outcomes compared to those without treatment success (462/469, 99% vs. 183/311, 59%; P 0.0001).. Low BMI is associated with poor sputum culture conversion in MDR-/RMP-resistant TB patients. Lack of culture conversion can impact successful treatment outcomes.

Topics: Adolescent; Adult; Antitubercular Agents; Body Mass Index; Diagnostic Tests, Routine; Disease Management; Drug Resistance, Multiple, Bacterial; Female; Humans; India; Male; Middle Aged; Retrospective Studies; Rifampin; Sputum; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Young Adult

Multidrug-resistant tuberculosis (MDR-TB) is growing globally and becoming a major challenge for national TB control programs. Therefore, rapid identification of MDR strains of Mycobacterium tuberculosis and monitoring their transmission could contribute significantly to the control of TB. The GenoType MTBDRplus assay has been recommended by the World Health Organization to identify rifampicin (RIF)- and isoniazid (INH)-resistant M. tuberculosis isolates. This study was carried out to evaluate the performance of the GenoType MTBDRplus assay for the detection of RIF- and INH-resistant M. tuberculosis isolates in central Ethiopia.. A total of 279 M. tuberculosis strains isolated from active TB cases in central Ethiopia were evaluated for their drug sensitivity by the conventional drug-susceptibility test (DST) and compared with data derived from the GenoType MTBDRplus assay. The DST served as the gold standard for evaluating the GenoType MTBDRplus assay.. The sensitivity and specificity of the GenoType MTBDRplus assay for the detection of RIF-resistant M. tuberculosis isolates were 80.0% and 99.6%, respectively. Its sensitivity and specificity for the detection of INH-resistant M. tuberculosis isolates were 82.7% and 99.6%, respectively, whereas they were 75.0% and 100%, respectively, for the detection of MDR M. tuberculosis strains. The concordances of the GenoType MTBDRplus assay and the conventional DST for the detection of RIF and INH susceptibility were 80% (8/10) and 86.2% (25/29), respectively. Furthermore, the concordance of the two tests for the detection of MDR M. tuberculosis strains was 75%. Specific mutations were detected in 55.6% (5/9) of the RIF-resistant isolates, with the highest mutation rate (33.3%) for the rpoB gene (Codon S531L). For INH-resistant isolates, the highest mutation rate (88.8%) related to a katG mutation (Codon S315T1).. The findings of this study revealed that the GenoType MTBDRplus assay has high sensitivity and specificity for the detection of RIF and INH resistance. These preliminary data support the notion that the assay should be considered as an alternative to the DST for the characterization of MDR in M. tuberculosis isolates and the control of TB.

Topics: Antitubercular Agents; Drug Resistance, Bacterial; Ethiopia; Genotyping Techniques; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

The aim of this multicenter study was to evaluate the performance of the crystal violet decolorization assay (CVDA) for detection of multidrug resistant tuberculosis (MDR-TB). This study was performed in 11 centers in two phases. A total of 156 isolates were tested for INH and RIF resistance. In the phase I, 106 clinical isolates were tested in the Center 1-7. In the phase 2, 156 clinical isolates were tested in the center 1-6, center 8-11. Eighty six of 156 tested isolates were the same in phase I. Agreements were 96.2-96.8% for INH and 98.1-98.7% for RIF in the phase I-II, respectively. Mean time to obtain the results in the phase I was 14.3 ± 5.4 days. In the phase II, mean time to obtain the results was 11.6 ± 3.5 days. Test results were obtained within 14days for 62.3% (66/106) of isolates in the phase I and 81.4% (127/156) of isolates in the phase II. In conclusion, CVDA is rapid, reliable, inexpensive, and easy to perform for rapid detection of MDR-TB isolates. In addition, it could be adapted for drug susceptibility testing with all drugs both in developed and developing countries.

Topics: Calorimetry; Developed Countries; Gentian Violet; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Time Factors; Tuberculosis, Multidrug-Resistant

Tuberculosis (TB) is an infectious disease that is caused by Mycobacterium tuberculosis (M.tb). TB has high morbidity and mortality around the world.. To evaluate molecular-based methods performed directly on stool samples for the diagnosis of pulmonary tuberculosis (PTB) and to determine the susceptibility to Rifampicin (RMP) and Isoniazid (INH).. This is a descriptive study evaluating the performance of the PCR-based method for direct PTB diagnosis and to determine the susceptibility of RMP and INH using stool samples from PTB patients. The study was conducted between March 2011 and March 2014.. Three stool samples and three sputum samples (n=300 stool and 300 sputum) were collected from 100 PTB patients (75 pretreatment and 25 follow up). Stool samples (n=60) were also collected from 20 healthy individuals to serve as controls. DNA was extracted from stool samples using Chelex. The Genekam kit showed 100% sensitivity and 95.24% specificity for diagnosing new patients and showed 100% sensitivity and 80% specificity for follow-up patients. The Genotype MTBDR-plus assay showed 86.4% and 100% sensitivity and 98.1% and 97.8% specificity for determining INH and RMP sensitivity, respectively, in newly diagnosed patients and 85.7% and 94.4% sensitivity and specificity, respectively, for both INH and RMP in follow-up patients.. Molecular-based methods are promising techniques for the diagnosis and susceptibility testing of PTB when the ease of sample collection and the speed of diagnosis are taken into consideration. However, they are not as useful for assessing follow-up patients.

Topics: Adolescent; Adult; Case-Control Studies; Child; Feces; Female; Humans; Isoniazid; Male; Middle Aged; Polymerase Chain Reaction; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

With the spread of multidrug-resistant tuberculosis (MDR-TB) strains there is an increasing need for new accurate and cost-effective methods for a rapid diagnostic and drug susceptibility testing (DST), particularly in low-income countries where tuberculosis is hyperendemic. A colorimetric assay using 3-(4, 5-dimethylthiazol-2-yl)-2, 5- diphenyltetrazolium bromide (MTT) has been suggested as a promising method for DST, especially to rifampicin. In this study, we standardized and evaluated the MTT assay for a rapid direct detection of rifampicin and isoniazid resistant Mycobacterium tuberculosis strains from sputum specimens using Lowenstein-Jensen (LJ) culture medium as a gold standard. The MTT assay sensitivity, specificity, positive and negative predictive values for rifampicin were 100%, 86%, 100%, 99%, respectively. For isoniazid, the MTT assay had a 100% sensitivity, specificity, positive and negative predictive values. Interestingly, the MTT assay gave interpretable results within two weeks for 94% of the samples compared to 7-14 weeks for LJ media. Overall, an excellent agreement was observed between MTT assay and LJ proportion method (Kappa, 0.91 for rifampicin and 1.00 for isoniazid). In conclusion, the direct colorimetric MTT assay simultaneously detects susceptible and resistant strains of M. tuberculosis within three weeks. It significantly shortens the time required to obtain a DST result and could be a reliable alternative method for rapid detection of drug-resistant TB strains in high-TB-burden resource-limited settings.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antitubercular Agents; Cell Proliferation; Child; Colorimetry; Cross-Sectional Studies; Female; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Young Adult

The recent approval of new tuberculosis (TB) drugs raises hope for new and more effective anti-tuberculosis treatment regimens. The Global Alliance for TB Drug Development (TB Alliance) is committed to ensuring that new anti-tuberculosis drugs fulfill the needs of patients, their families and the local health services that serve the communities. Here we present highlights of the TB Alliance's pipeline of regimen development, with novel regimens for patients with drug-susceptible, multidrug-resistant and extensively drug-resistant TB. The ongoing clinical trials (STAND, NC-005, Nix-TB and LIN-CL001) are outlined and their rationale and goals presented.

Topics: Antitubercular Agents; Clinical Protocols; Diarylquinolines; Dose-Response Relationship, Drug; Ethambutol; Extensively Drug-Resistant Tuberculosis; Fluoroquinolones; Humans; Isoniazid; Linezolid; Moxifloxacin; Nitroimidazoles; Pyrazinamide; Randomized Controlled Trials as Topic; Research Design; Rifampin; Tuberculosis, Multidrug-Resistant

TB, caused by Mycobacterium tuberculosis, is one of the deadliest infections worldwide. The co-infection with HIV and the emergence of multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) strains have further increased the burden for this disease. In the attempt to respond to the constant need of novel therapeutic options, we herein report the discovery of 2,4-diphenyl-1H-imidazoles as effective antitubercular agents, with MIC in the low micromolar range against actively replicating and persistent M. tuberculosis strains. The good activity, along with the lack of toxicity and the feasible synthesis, underscore their value as novel scaffolds for the development of new anti-TB drugs.

Topics: Antitubercular Agents; Dose-Response Relationship, Drug; Drug Design; Drug Discovery; Drug Repositioning; Microbial Sensitivity Tests; Molecular Structure; Mycobacterium tuberculosis; Structure-Activity Relationship; Tuberculosis, Multidrug-Resistant

A series of novel fluoroquinolone derivatives containing an 3-alkoxyimino-4-(cyclopropylanimo)methylpyrrolidine moiety were designed, synthesized and evaluated for their biological activity. Our results revealed that 19b2 shows good activity against MTB H37Rv ATCC 27294 (MIC: <0.25 μg/mL) and MDR-MTB 6133 clinical isolate (MIC: 0.11 μg/mL). Most of them have potent potency against Gram-positive strains, although they are generally poor active against Gram-negative strains. Especially, compounds 22b1 and 23a3 (MICs: <0.008-8 μg/mL) were found to 2-128 times more potent than ciprofloxacin and levofloxacin against all of the tested Gram-positive strains including quinolone-resistant MRSA, MRSE, Enterococcus faecium and Enterococcus faecalis.

Topics: Anti-Bacterial Agents; Dose-Response Relationship, Drug; Enterococcus; Fluoroquinolones; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Pyrrolidines; Structure-Activity Relationship; Tuberculosis, Multidrug-Resistant

Topics: Adult; Antibiotics, Antitubercular; DNA, Bacterial; Female; Follow-Up Studies; Humans; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Ocular

Multi-drug resistant tuberculosis (MDR-TB) is caused by Mycobacterium tuberculosis strains resistant to at least two of the most effective anti-tuberculosis drugs (i.e., isoniazid and rifampicin). Therapeutic regimens based on second- and third-line anti-tuberculosis medicines showed poor efficacy, safety, and tolerability profiles. It was estimated that in 2012 the multi-drug resistant tuberculosis incidence ranged from 300,000 to 600,000 cases, mainly diagnosed in the Eastern European and Central Asian countries. The highest proportion of cases is among individuals previously exposed to anti-tuberculosis drugs. Three main conditions can favour the emergence and spread of multi-drug resistant tuberculosis: the poor implementation of the DOTS strategy, the shortage or the poor quality of the anti-tuberculosis drugs, and the poor therapeutic adherence of the patients to the prescribed regimens. Consultation with tuberculosis experts (e.g., consilium) is crucial to tailor the best anti-tuberculosis therapy. New therapeutic options are necessary: bedaquiline and delamanid seem promising drugs; in particular, during the development phase they demonstrated a protective effect against the emergence of further resistances towards the backbone drugs. In the recent past, other antibiotics have been administered off-label: the most relevant efficacy, safety, and tolerability profile was proved in linezolid-, meropenem/clavulanate-, cotrimoxazole-containing regimens. New research and development activities are needed in the diagnostic, therapeutic, preventive fields.

Topics: Antitubercular Agents; Directly Observed Therapy; Drug Design; Humans; Isoniazid; Medication Adherence; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Rifampin (RIF) is the most important first-line antituberculosis drug, and resistance to this drug may result in treatment failures. We evaluated the diagnostic performances of recently introduced, molecular assays for the detection of RIF resistance.. A total of 100 isolates (50 RIF resistant and 50 RIF susceptible) were studied. Their RIF resistances were determined by conventional drug-susceptibility test. These results were compared with those of three molecular assays: Xpert MTB/RIF assay (MTB is Mycobacterium tuberculosis), Sacace MTB Real-TM resistance, and AdvanSure MDR-TB GenoBlot assay (MDR is multidrug resisitant).. Sensitivities for RIF resistance detection of Xpert MTB/RIF assay, Sacace MTB Real-TM resistance, and Advansure GenoBlot assay were 94.0%, 91.8%, and 84.0%, respectively. Their specificities for RIF resistance detection were all 100%.. Three molecular assays for the detection of RIF resistance have various performances. Xpert MTB/RIF assay shows the highest sensitivity among the three molecular assays and can be an effective choice in clinical laboratories.

Topics: Bacterial Proteins; Catalase; DNA-Directed RNA Polymerases; Drug Resistance, Bacterial; Humans; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Oxidoreductases; Polymerase Chain Reaction; Rifampin; Tuberculosis, Multidrug-Resistant

SUMMARY We analysed Mycobacterium tuberculosis strains from children, hospitalized from January 2004 to July 2008 in the largest paediatric hospital complex in Cambodia. Specimens were tested for drug susceptibility and genotypes. From the 260 children, 161 strains were available. The East African-Indian genotype family was the most common (59.0%), increasing in frequency with distance from the Phnom Penh area, while the frequency of the Beijing genotype family strains decreased. The drug resistance pattern showed a similar geographical gradient: lowest in the northwest (4.6%), intermediate in the central (17.1%), and highest in the southeastern (30.8%) parts of the country. Three children (1.9%) had multidrug-resistant tuberculosis. The Beijing genotype and streptomycin resistance were significantly associated (P < 0.001). As tuberculosis in children reflects recent transmission patterns in the community, multidrug resistance levels inform about the current quality of the tuberculosis programme.

Topics: Adolescent; Antitubercular Agents; Cambodia; Child; Child, Preschool; DNA, Bacterial; Drug Resistance, Multiple, Bacterial; Female; Genotype; Humans; Infant; Infant, Newborn; Isoniazid; Male; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Streptomycin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Multidrug-resistant tuberculosis (MDR-TB) (resistance to at least isoniazid and rifampicin) will influence the future of global TB control. 88% of estimated MDR-TB cases occur in middle- or high-income countries, and 60% occur in Brazil, China, India, the Russian Federation and South Africa. The World Health Organization collects country data annually to monitor the response to MDR-TB. Notification, treatment enrolment and outcome data were summarised for 30 countries, accounting for >90% of the estimated MDR-TB cases among notified TB cases worldwide. In 2012, a median of 14% (interquartile range 6-50%) of estimated MDR-TB cases were notified in the 30 countries studied. In 15 of the 30 countries, the number of patients treated for MDR-TB in 2012 (71 681) was >50% higher than in 2011. Median treatment success was 53% (interquartile range 40-70%) in the 25 countries reporting data for 30 021 MDR-TB cases who started treatment in 2010. Although progress has been noted in the expansion of MDR-TB care, urgent efforts are required in order to provide wider access to diagnosis and treatment in most countries with the highest burden of MDR-TB.

Topics: Antitubercular Agents; Brazil; China; Communicable Disease Control; Data Collection; Global Health; Humans; India; Isoniazid; Poverty; Rifampin; Russia; South Africa; Treatment Outcome; Tuberculosis, Multidrug-Resistant; World Health Organization

To evaluate the performance of Xpert MTB/RIF (MTB/RIF) in the county-level tuberculosis (TB) laboratory in China.. From April 2011 to January 2012, patients with suspected multidrug-resistant tuberculosis (MDR-TB) and non-MDR-TB were enrolled consecutively from four county-level TB laboratories. The detection of Mycobacterium tuberculosis (MTB) by MTB/RIF was compared to detection by Löwenstein-Jensen culture. The detection of rifampin resistance was compared to detection by conventional drug-susceptibility testing. The impact of multiple specimens on the performance of MTB/RIF was also evaluated.. A total of 2142 suspected non-MDR-TB cases and 312 suspected MDR-TB cases were enrolled. For MTB detection in suspected non-MDR-TB cases, the sensitivity and specificity of MTB/RIF were 94.4% and 90.2%, respectively. The sensitivity in smear-negative patients was 88.8%. For the detection of rifampin resistance in suspected non-MDR-TB cases, the sensitivity and specificity of MTB/RIF were 87.1% and 97.9%, respectively. For the detection of rifampin resistance in suspected MDR-TB cases, the sensitivity and specificity of MTB/RIF were 87.1% and 91.0%, respectively. Using multiple sputum specimens had no significant influence on the performance of MTB/RIF for MTB detection.. The introduction of MTB/RIF could increase the accuracy of detection of MTB and rifampin resistance in peripheral-level TB laboratories in China. One single specimen is adequate for TB diagnosis by MTB/RIF.

Topics: China; Clinical Laboratory Techniques; Drug Resistance, Bacterial; Feasibility Studies; Female; Humans; Male; Mycobacterium tuberculosis; Real-Time Polymerase Chain Reaction; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

The aim of this study was to explore the population structure of multidrug-resistant (MDR) tuberculosis strains and distribution of resistance-associated nucleotide alteration among the different genotype MDR strains in China.. The genotypes of 376 MDR strain were analyzed by 15-loci MIRU-VNTR and RD105 deletion-targeted multiplex PCR (DTM-PCR) method. In addition, all the MDR isolates were sequenced for genetic mutations conferring rifampicin (rpoB) and isonizid resistance (katG, inhA and oxyR-ahpC).. Among the 376 MDR isolates, 261 (69.4%) belonged to Beijing genotype, including 177 modern Beijing strains (67.8%) and 84 ancient Beijing (32.2%) strains. The percentages of streptomycin-resistant, kanamycin-resistant, pre-XDR and XDR TB in modern Beijing genotype were significantly lower than ancient genotype (P < 0.05). The Beijing MDR strains had significantly higher proportions of ofloxacin-resistant and pre-XDR isolates than non-Beijing strains (P < 0.01). In addition, the clustering rate of modern Beijing strains was significantly higher than that of ancient Beijing strains (46.3% vs. 11.9%, P < 0.01). 94.7% and 79.3% of MDR isolates harbored genetic mutations conferring rifampicin and isonizid resistance, respectively, and the most prevalent mutation was located in codon rpoB531 and katG315. In addition, the rpoB531 and katG mutation were more frequently observed among Beijing genotype strains than non-Beijing strains, while non-Beijing genotype showed stronger association with isolates lacking mutation in rifampicin resistance determination region (P < 0.05).. Our findings demonstrated that ancient Beijing MDR strains were associated with drug resistance, while modern Beijing MDR strains were more likely to be clustered.

Topics: Antitubercular Agents; Bacterial Proteins; Catalase; China; DNA-Directed RNA Polymerases; Drug Resistance, Multiple, Bacterial; Genetic Variation; Genotype; Isoniazid; Molecular Epidemiology; Molecular Typing; Multiplex Polymerase Chain Reaction; Mutation; Mycobacterium tuberculosis; Oxidoreductases; Phylogeny; Rifampin; Sequence Analysis, DNA; Tuberculosis, Multidrug-Resistant

Symptom-based screening for tuberculosis (TB) disease is limited by poor performance of symptom screening in several key populations. We tested the hypothesis that pooling sputum from multiple individuals for Xpert(®) MTB/RIF testing would reduce the number of tests required while retaining an acceptable sensitivity, thus allowing the use of Xpert for TB screening.. We compared pooling ratios that would require the least number of assays using Xpert and determined that for a population with a TB prevalence of approximately 3%, a 1:5 pooling ratio is optimal. To evaluate sensitivity, we generated pools of one specimen with known Mycobacterium tuberculosis culture positivity (smear microscopy-positive or -negative) with four culture-negative specimens.. All 20 of the pools generated from a smear- and culture-positive sputum sample were positive using Xpert. Of the 22 pools with a smear-negative, culture-positive sample, we included 17 in the analysis, of which 13 (76%) were Xpert-positive.. Pooling of sputum samples using Xpert achieved reasonable sensitivity and warrants further evaluation of the systematic screening of high TB prevalence populations.

Topics: Drug Resistance, Bacterial; Humans; Mycobacterium tuberculosis; Population Surveillance; Prevalence; Rifampin; Risk Factors; Sensitivity and Specificity; Specimen Handling; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Although standardised multidrug treatments exist, mortality among hospitalised tuberculosis (TB) patients is high.. To characterise TB patients requiring acute hospital care and identify factors associated with in-hospital mortality.. Using a Japanese national database of acute-care hospitals, we identified patients with sputum smear-positive pulmonary TB who were discharged (both deceased and alive) between July 2010 and March 2013. Demographic characteristics, comorbidity, procedures and treatments were examined. We performed a multivariable logistic regression analysis to identify risk factors for in-hospital mortality.. Of 877 treated patients (566 males, mean age 74.5 years) identified, 152 (17.3%) died. A standard four-drug regimen of isoniazid (INH), rifampicin (RMP), ethambutol (EMB) and pyrazinamide was given to 279 (31.8%) patients, and INH, RMP and EMB to 335 (38.2%) patients. Multivariable analysis showed that the three-drug regimen was significantly associated with higher rates of in-hospital mortality (OR 1.87, 95%CI 1.07-3.27, P = 0.028). Other factors associated with in-hospital death were age, male sex, smoking habit, emergency admission, dementia and severe respiratory condition.. The risk factors for in-hospital death identified include the use of the three-drug regimen. Treatment choice could influence the outcome of hospitalised TB patients.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antitubercular Agents; Child; Child, Preschool; Ethambutol; Female; Hospital Mortality; Hospitalization; Humans; Infant; Infant, Newborn; Isoniazid; Japan; Logistic Models; Male; Middle Aged; Multivariate Analysis; Patient Discharge; Pyrazinamide; Retrospective Studies; Rifampin; Risk Factors; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

The cost of multidrug-resistant tuberculosis (MDR-TB) treatment is a major barrier to treatment scale-up in South Africa.. To estimate and compare the cost of treatment for rifampicin-resistant tuberculosis (RR-TB) in South Africa in different models of care in different settings.. We estimated the costs of different models of care with varying levels of hospitalisation. These costs were used to calculate the total cost of treating all diagnosed cases of RR-TB in South Africa, and to estimate the budget impact of adopting a fully or partially decentralised model vs. a fully hospitalised model.. The fully hospitalised model was 42% more costly than the fully decentralised model (US$13,432 vs. US$7753 per patient). A much shorter hospital stay in the decentralised models of care (44-57 days), compared to 128 days of hospitalisation in the fully hospitalised model, was the key contributor to the reduced cost of treatment. The annual total cost of treating all diagnosed cases ranged from US$110 million in the fully decentralised model to US$190 million in the fully hospitalised model.. Following a more decentralised approach for treating RR-TB patients could potentially improve the affordability of RR-TB treatment in South Africa.

Topics: Antitubercular Agents; Health Care Costs; Hospitalization; Humans; Length of Stay; Models, Economic; Rifampin; South Africa; Tuberculosis, Multidrug-Resistant

To compare 3 different molecular techniques to detect the Mycobacterium tuberculosis genome in vitreous fluid of eyes with multifocal serpiginoid choroiditis (MSC).. Prospective, interventional case series.. Eleven patients (11 eyes) with active MSC in at least 1 eye underwent diagnostic pars plana vitrectomy (PPV) between October 2012 and December 2013.. Vitreous fluid samples were subjected to multitargeted polymerase chain reaction (PCR) for a M. tuberculosis assay, the Gene Xpert MTB/RIF assay (Cepheid, Sunnyvale, CA), and a line probe assay (GenoType MTBDRplus; Hain Lifescience, GmbH, Nehren, Germany). The samples with positive results were subjected to rpoB gene sequencing to demonstrate rifampicin resistance. The clinical details, digital fundus imaging, and treatment details and outcomes also were noted.. Detection of the M. tuberculosis genome and rifampicin resistance in the vitreous samples.. Of the 11 eyes subjected to PPV, the multitargeted PCR results for tuberculosis were positive for 10 eyes, the MTBDRplus assay results were positive in 6 eyes, and the Gene Xpert MTB/RIF assay results were positive in 4 eyes. Rifampicin resistance was detected in 3 eyes by rpoB gene sequencing, in 3 eyes by the MTBDRplus assay, and in 1 eye by the Gene Xpert MTB/RIF assay.. We detected the M. tuberculosis genome in the vitreous fluid of eyes with MSC using 3 different molecular techniques. Rifampicin resistance was detected for the first time in eyes with MSC.

Topics: Adolescent; Adult; Antibiotics, Antitubercular; Antitubercular Agents; Choroiditis; Drug Resistance, Bacterial; Drug Therapy, Combination; Female; Fluorescein Angiography; Genome, Bacterial; Humans; Male; Middle Aged; Molecular Diagnostic Techniques; Multifocal Choroiditis; Mycobacterium tuberculosis; Polymerase Chain Reaction; Prospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Ocular; Vitrectomy; Vitreous Body; Young Adult

Topics: Antitubercular Agents; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Among 452 samples that were positive by the Xpert MTB/RIF (Xpert) assay and MGIT 960 system (MGIT), 440 and 10 Mycobacterium tuberculosis samples were detected as rifampin susceptible and rifampin resistant, respectively. Two isolates that were rifampin susceptible by the MGIT system were rifampin resistant by the Xpert assay. rpoB sequencing identified a silent (CTG521TTG) mutation in one isolate and a missense (GAC516TAC) mutation in another. The detection of rifampin resistance is imperfect with both the Xpert assay and MGIT system. Any discordant rifampin resistance results should be confirmed by sequencing of the rpoB gene.

Topics: Antitubercular Agents; Bacterial Proteins; Bacteriological Techniques; DNA-Directed RNA Polymerases; Gene Expression Regulation, Bacterial; Humans; Kuwait; Molecular Sequence Data; Rifampin; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Female; Humans; Isoniazid; Male; Rifampin; Tuberculosis, Multidrug-Resistant

Topics: Antitubercular Agents; Female; Humans; Isoniazid; Male; Rifampin; Tuberculosis, Multidrug-Resistant

A critical challenge in providing TB care to People Living with HIV (PLHIV) is establishing an accurate bacteriological diagnosis. Xpert MTB/RIF, a highly sensitive and specific rapid tool, offers a promising solution in addressing these challenges. This study presents results from PLHIV taking part in a large demonstration study across India wherein upfront Xpert MTB/RIF testing was offered to all presumptive PTB cases in public health facilities.. The study covered a population of 8.8 million across 18 sub-district level tuberculosis units (TU), with one Xpert MTB/RIF platform established at each TU. All HIV-infected patients suspected of TB (both TB and Drug Resistant TB (DR-TB)) accessing public health facilities in study area were prospectively enrolled and provided upfront Xpert MTB/RIF testing.. 2,787 HIV-infected presumptive pulmonary TB cases were enrolled and 867 (31.1%, 95% Confidence Interval (CI) 29.4‒32.8) HIV-infected TB cases were diagnosed under the study. Overall 27.6% (CI 25.9-29.3) of HIV-infected presumptive PTB cases were positive by Xpert MTB/RIF, compared with 12.9% (CI 11.6-14.1) who had positive sputum smears. Upfront Xpert MTB/RIF testing of presumptive PTB and DR-TB cases resulted in diagnosis of 73 (9.5%, CI 7.6‒11.8) and 16 (11.2%, CI 6.7‒17.1) rifampicin resistance cases, respectively. Positive predictive value (PPV) for rifampicin resistance detection was high 97.7% (CI 89.3‒99.8), with no significant difference with or without prior history of TB treatment.. The study results strongly demonstrate limitations of using smear microscopy for TB diagnosis in PLHIV, leading to low TB and DR-TB detection which can potentially lead to either delayed or sub-optimal TB treatment. Our findings demonstrate the usefulness and feasibility of addressing this diagnostic gap with upfront of Xpert MTB/RIF testing, leading to overall strengthening of care and support package for PLHIV.

Topics: Drug Resistance, Bacterial; Female; HIV Infections; Humans; India; Male; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

The Xpert(®) MTB/RIF assay has demonstrated robust capability for diagnosing tuberculosis (TB) and rifampin (RMP) resistance. Optimal use of Xpert in diverse settings will require knowledge of challenges when interpreting the results. We present three selected cases from the United States, a low-burden TB setting, to highlight important clinical scenarios encountered with Xpert testing: rapid RMP resistance detection in a patient with pre-extensively drug-resistant TB who immigrated from the Philippines, false-positive RMP resistance detection, and Mycobacterium tuberculosis detection in a culture-negative patient. These cases demonstrate that a low pre-test probability of TB or drug-resistant TB can complicate the interpretation of the Xpert assay.

Topics: Adult; Aged; Antibiotics, Antitubercular; Drug Resistance, Multiple, Bacterial; Female; HIV Seronegativity; Humans; Male; Middle Aged; Molecular Diagnostic Techniques; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Rifampin; Specimen Handling; Sputum; Treatment Outcome; Tuberculin Test; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; United States

The aim of the present study was to evaluate the effect of the combination of rifampicin (RIF) and verapamil (VP) against the Mycobacterium tuberculosis H37Rv reference strain and six multidrug-resistant (MDR) M. tuberculosis clinical isolates by determining Time-Kill Curves and the ability to efflux drug by fluorometry. The RIF+VP combination showed synergism in one MDR clinical isolate. For the other five MDR clinical isolates, the drug combination showed no interaction. The MDR clinical isolate had lower ethidium bromide (EtBr) accumulation when exposed to the RIF+VP combination, compared with RIF and VP exposure alone. The other MDR clinical isolates showed no significant difference in EtBr accumulation. These results suggest greater efflux action in one of the MDR clinical isolates compared with the M. tuberculosis H37Rv reference strain. The other five MDR isolates may have additional mechanisms of drug resistance to RIF. The use of the RIF+VP combination made one MDR bacillus more susceptible to RIF probably by inhibiting efflux pumps, and this combination therapy, in some cases, may contribute to a reduction of resistance to RIF in M. tuberculosis.

Topics: Antibiotics, Antitubercular; Calcium Channel Blockers; Drug Resistance, Multiple, Bacterial; Ethidium; Humans; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant; Verapamil

Rifampicin (RIF) resistance is a risk factor for poor outcome in tuberculosis (TB). In Mycobacterium tuberculosis, both target gene mutation and efflux pumps have major roles in the resistance to anti-TB drugs. This study aimed to determine whether RIF induces efflux pump activation in RIF-monoresistant M. tuberculosis strains. Here, we took advantage of 16 RIF-monoresistant M. tuberculosis clinical isolates to evaluate the expression of 27 putative drug efflux pump genes and measured the influence of four drug efflux pump inhibitors, carbonyl cyanide m-chlorophenyl hydrazone (CCCP), verapamil (VP), thioridazine (TZ) and chlorpromazine (CPZ), on the RIF MICs of these strains. Eight of the 16 RIF-monoresistant isolates carried mutations in rpoB and overexpressed one or two of the following putative efflux pump genes: Rv2333, drrB, drrC, Rv0842, bacA and efpA. CCCP, VP, TZ and CPZ lowered the RIF MICs greater than fourfold in 6, 12, 9 and 12 isolates, respectively. The lowered RIF MICs by VP and CPZ were identical and stronger than CCCP (P-values were all 0.033). In conclusion, the efflux pumps Rv2333, DrrB, DrrC, Rv0842, BacA and EfpA may have a role in RIF resistance in addition to classical mutations in the rpoB gene, and the addition of VP and CPZ could significantly increase RIF susceptibility in RIF-monoresistant M. tuberculosis.

Topics: Adult; Antitubercular Agents; DNA-Directed RNA Polymerases; Drug Resistance, Bacterial; Gene Expression Profiling; Gene Expression Regulation, Bacterial; Humans; Membrane Transport Proteins; Microbial Sensitivity Tests; Mutation, Missense; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

To measure the diagnostic yield of Bronchoalveolar Lavage (BAL) gene Xpert (Xpert MTB/RIF assay), to detect Mycobacterium tuberculosis (MTB) and rifampicin resistance and compare it with that of mycobacterial cultures in a suspected case of pulmonary tuberculosis.. An analytical study.. Department of Pulmonology, Fauji Foundation Hospital (FFH), Rawalpindi, from December 2012 to August 2013.. BAL specimens of 93 patients with suspected pulmonary tuberculosis with smear-negative or sputumscarce disease, who presented to the Department of Pulmonology, FFH, Rawalpindi were inducted. A smear-negative case was one in whom three consecutive early morning sputum samples did not reveal acid fast bacilli when examined by microscopy with Zeihl Nelson (ZN) stain. Patients who had sputum amount less than 1 ml were defined to have sputumscarce disease. The same was evaluated with ZN stain, gene Xpert and mycobacterial cultures. Sensitivity analysis was carried out using culture as the gold standard.. The frequency of positive mycobacterial cultures was 85 (91.4%). The sensitivity, specificity, positive predictive value and negative predictive values of BAL gene Xpert to detect Mycobacterium tuberculosis were 91.86%, 71.42%, 97.53% and 41.66% respectively. Xpert MTB/RIF assay had a sensitivity and specificity of 83.33% and 100% to detect rifampicin resistance.. Bronchoalveolar lavage gene Xpert had a superior diagnostic yield in patients with either smear-negative or sputum-scarce pulmonary tuberculosis. Hence a positive Xpert MTB/RIF assay may be a useful adjunct to diagnosis and detection of MDR-TB in bronchoalveolar lavage specimens.

Topics: Adult; Aged; Aged, 80 and over; Antibiotics, Antitubercular; Bacterial Proteins; Bronchoalveolar Lavage; Bronchoalveolar Lavage Fluid; DNA-Directed RNA Polymerases; Drug Resistance, Bacterial; Female; Humans; Male; Middle Aged; Mycobacterium tuberculosis; Nucleic Acid Amplification Techniques; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Multidrug resistant tuberculosis (MDR-TB) poses problems in treatment, costs and treatment outcomes. It is not known if classically described risk factors for MDR-TB in other countries are the same in Mexico and the frequency of the association between diabetes mellitus (DM) and MDR-TB in our country is not clear. We undertook this study to analyze risk factors associated with the development of MDR-TB, with emphasis on DM.. A case-control study in the state of San Luis Potosi (SLP), Mexico was carried out. All pulmonary MDR-TB patients diagnosed in the state of SLP between 1998 and 2013 (36 cases) evaluated at a state pharmacoresistant tuberculosis (TB) clinic and committee; 139 controls were randomly selected from all pulmonary non-multidrug-resistant tuberculosis (non-MDR-TB) cases identified between 2003 and 2008. Cases and controls were diagnosed and treated under programmatic conditions.. Age, gender, malnutrition, being a health-care worker, HIV/AIDS status, and drug abuse were not significantly different between MDR-TB and non-MDR-TB patients. Significant differences between MDR-TB and non-MDR-TB patients were DM (47.2 vs. 28.1%; p = 0.028); previous anti-TB treatments (3 vs. 0, respectively; p <0.001), and duration of first anti-TB treatment (8 vs. 6 months, respectively; p <0.001).. MDR-TB and DM are associated in 47.2% of MDR TB cases (17/36) in this study. Other recognized factors were not found to be significantly different in MDR-TB compared to non-MDR-TB in this study. Cost-feasible strategies must be implemented in the treatment of DM-TB in order to prevent the selection of MDR-TB.

Topics: Adult; Ambulatory Care Facilities; Antibiotics, Antitubercular; Bacterial Typing Techniques; Case-Control Studies; Diabetes Complications; Diabetes Mellitus; Drug Resistance, Multiple, Bacterial; Female; Health Care Costs; Health Personnel; Humans; Isoniazid; Male; Mexico; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Rifampin; Risk Factors; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

The influence of Mycobacterium tuberculosis (MTB) lineages/sublineages on unfavorable tuberculosis (TB) treatment outcomes is poorly understood. We investigated the effects of Beijing genotype sublineages and other factors contributing to treatment outcome. Patients newly diagnosed with sputum smear-positive and culture-positive TB in Hanoi, Vietnam, participated in the study. After receiving anti-TB treatment, they were intensively followed up for the next 16 months. MTB isolates collected before treatment were subjected to drug susceptibility testing, and further analyzed to determine MTB (sub) lineages and their clonal similarities. Of 430 patients, 17 had treatment failure and 30 had TB recurrence. Rifampicin resistance was associated with treatment failure {adjusted odds ratio = 6.64 [95% confidence interval (CI), 1.48-29.73]}. The modern Beijing genotype was significantly associated with recurrent TB within 16 months [adjusted hazard ratio = 3.29 (95% CI, 1.17-9.27)], particularly after adjustment for the relevant antibiotic resistance. Human immunodeficiency virus coinfection and severity on chest radiographs were not significantly associated with unfavorable outcomes. Our findings provide further understanding of the influence of MTB strains on unfavorable treatment outcomes. Multiple risk factors should be considered for the optimal management of TB.

Topics: Adult; Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Female; Genotype; Humans; Logistic Models; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Odds Ratio; Phenotype; Proportional Hazards Models; Recurrence; Rifampin; Risk Factors; Sputum; Time Factors; Treatment Failure; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Vietnam; Young Adult

This study correlates MICs of rifampicin (RIF) and isoniazid (INH) with GenoType MTBDRplus assay results for drug-resistant Mycobacterium tuberculosis (MTB) clinical isolates. MICs of RIF and INH were established for 84 and 90 isolates, respectively, testing 7 concentrations of each drug. Genotypic resistance to each drug was determined by GenoType MTBDRplus assay with 50 representative mutations confirmed by pyrosequencing, with mutations in the rpoB gene associated with RIF resistance and mutations in the katG and/or inhA genes associated with INH resistance. Based upon the correlation of MICs with specific genetic profiles, relative resistance levels were established for each isolate. Results indicate that MTB phenotypic resistance, currently based upon the testing of isolate susceptibility to a single drug concentration, may be more accurately profiled via quantitative MICs, and therefore, the correlation of molecular diagnostic results with specific MICs may allow for more optimal treatment of infections.

Topics: Antitubercular Agents; Bacterial Proteins; Catalase; DNA-Directed RNA Polymerases; Drug Resistance, Multiple, Bacterial; Genotype; Genotyping Techniques; Humans; Isoniazid; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Oxidoreductases; Phenotype; Rifampin; Tuberculosis, Multidrug-Resistant

Topics: Antibiotics, Antitubercular; DNA; DNA Mutational Analysis; Eswatini; Humans; Mycobacterium tuberculosis; Rifampin; Tandem Repeat Sequences; Tuberculosis, Multidrug-Resistant

Effective tuberculosis (TB) control has been hindered by the emergence of multidrug-resistant TB (MDR-TB).. To analyse the frequency of drug resistance among presumed cases of drug-resistant TB in the state of Punjab, India, and to determine the frequency of various genetic mutations detected using the line-probe assay (LPA).. Eight hundred patients with presumptive drug-resistant TB were enrolled under the programmatic management of drug-resistant TB under India's Revised National Tuberculosis Control Programme. Sputum samples from these patients were subjected to smear microscopy and LPA. Clinicodemographic details along with drug resistance patterns and genetic mutations were studied.. After excluding non-eligible samples, 545 samples were analysed, of which 290 (53.2%) showed resistance. Isoniazid and rifampicin (RMP) monoresistance were detected in respectively 9.3% (51/545) and 18% (98/545) of samples, while MDR was present in 25.8% (141/545) of samples. Of the MDR-TB cases, 2.1% (3/141) were treatment-naïve, while 90.8% (128/141) were on retreatment. The most common mutation conferring RMP resistance was S531L.. All patients undergoing retreatment for TB should be tested for drug susceptibility at the initial evaluation. Factors responsible for high MDR-TB and heteroresistance in Punjab need further studies.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antitubercular Agents; Child; Child, Preschool; Female; Humans; India; Isoniazid; Male; Middle Aged; Mutation; Mycobacterium tuberculosis; Retreatment; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Young Adult

Nomadic populations are often isolated and have difficulty accessing health care, leading to increased morbidity and mortality. Although Nigeria has one of the highest tuberculosis (TB) burdens in Africa, case detection rates remain relatively low.. Active case finding for TB among nomadic populations was implemented over a 2-year period in Adamawa State. A total of 378 community screening days were organised with local leaders; community volunteers provided treatment support. Xpert(®) MTB/RIF was available for nomads with negative smear results.. Through active case finding, 96 376 nomads were verbally screened, yielding 1310 bacteriologically positive patients. The number of patients submitting sputum for smear microscopy statewide increased by 112% compared with the 2 years before the intervention. New smear-positive notifications increased by 49.5%, while notifications of all forms of TB increased by 24.5% compared with expected notifications based on historical trends. Nomads accounted for respectively 31.4% and 26.0% of all smear-positive and all forms TB notifications. Pre-treatment loss to follow-up and treatment outcomes were similar among nomads and non-nomads.. Nomads in Nigeria have high TB rates, and active case-finding approaches may be useful in identifying and successfully treating them. Large-scale interventions in vulnerable populations can improve TB case detection.

Topics: Coinfection; Female; HIV Infections; Humans; Male; Microscopy; Mycobacterium tuberculosis; Nigeria; Rifampin; Sputum; Transients and Migrants; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Revised National TB Control Programme (RNTCP) in India recommends that all previously-treated TB (PT) patients are offered drug susceptibility testing (DST) at diagnosis, using rapid diagnostics and screened out for rifampicin resistance before being treated with standardized, eight-month, retreatment regimen. This is intended to improve the early diagnosis of rifampicin resistance and its appropriate management and improve the treatment outcomes among the rest of the patients. In this state-wide study from Gujarat, India, we assess proportion of PT patients underwent rapid DST at diagnosis and the impact of this intervention on their treatment outcomes.. This is a retrospective cohort study involving review of electronic patient-records maintained routinely under RNTCP. All PT patients registered for treatment in Gujarat during January-June 2013 were included. Information on DST and treatment outcomes were extracted from 'presumptive DR-TB patient register' and TB treatment register respectively. We performed a multivariate analysis to assess if getting tested is independently associated with unfavourable outcomes (death, loss-to-follow-up, failure, transfer out).. Of 5,829 PT patients, 5306(91%) were tested for drug susceptibility with rapid diagnostics. Overall, 71% (4,113) TB patients were successfully treated - 72% among tested versus 60% among non-tested. Patients who did not get tested at diagnosis had a 34% higher risk of unsuccessful outcomes as compared to those who got tested (aRR - 1.34; 95% CI 1.20-1.50) after adjusting for age, sex, HIV status and type of TB. Unfavourable outcomes (particularly failure and switched to category IV) were higher among INH-resistant patients (39%) as compared to INH-sensitive (29%).. Offering DST at diagnosis improved the treatment outcomes among PT patients. However, even among tested, treatment outcomes remained suboptimal and were related to INH resistance and high loss-to-follow-up. These need to be addressed urgently for further progress.

Topics: Adolescent; Adult; Antitubercular Agents; Drug Resistance, Bacterial; Female; Humans; India; Male; Middle Aged; Mycobacterium tuberculosis; Retrospective Studies; Rifampin; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

Several molecular assays to detect resistance to Rifampin, the Fluoroquinolones, and Aminoglycosides in Mycobacterium tuberculosis (M. tuberculosis) have been recently described. A systematic approach for comparing these assays in the laboratory is needed in order to determine the relative advantage of each assay and to decide which ones should be advanced to evaluation. We performed an analytic comparison of a Sloppy Molecular Beacon (SMB) melting temperature (Tm) assay and a Dual labeled probe (DLP) Tm assay. Both assays targeted the M. tuberculosis rpoB, gyrA, rrs genes and the eis promoter region. The sensitivity and specificity to detect mutations, analytic limit of detection (LOD) and the detection of heteroresistance were tested using a panel of 56 clinical DNA samples from drug resistant M. tuberculosis strains. Both SMB and DLP assays detected 29/29 (100%) samples with rpoB RRDR mutations and 3/3 (100%) samples with eis promoter mutations correctly. The SMB assay detected all 17/17 gyrA mutants and 22/22 rrs mutants, while the DLP assay detected 16/17 (94%) gyrA mutants and 12/22 (55%) rrs mutants. Both assays showed comparable LODs for detecting rpoB and eis mutations; however, the SMB assay LODs were at least two logs better for detecting wild type and mutants in gyrA and rrs targets. The SMB assay was also moderately better at detecting heteroresistance. In summary, both assays appeared to be promising methods to detect drug resistance associated mutations in M. tuberculosis; however, the relative advantage of each assay varied under each test condition.

Topics: Aminoglycosides; Antitubercular Agents; DNA Mutational Analysis; DNA, Bacterial; Fluoroquinolones; Humans; Microbial Sensitivity Tests; Molecular Diagnostic Techniques; Mutation; Mycobacterium tuberculosis; Polymerase Chain Reaction; Reproducibility of Results; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant

The performance of the BluePoint MycoID plus kit (Bio Concept Corporation, Taichung, Taiwan), which was designed to simultaneously detect Mycobacterium tuberculosis (MTB), rifampin- and isoniazid-resistant MTB, and nontuberculous mycobacteria (NTM) was first evaluated with 950 consecutive positive cultures in Mycobacterium Growth Indicator Tube (MGIT) system (BACTEC, MGIT 960 system, Becton-Dickinson, Sparks) from clinical respiratory specimens. The discrepant results between kit and culture-based identification were finally assessed by 16S rRNA gene sequencing and clinical diagnosis. The accuracy rate of this kit for identification of all Mycobacterium species was 96.3% (905/940). For MTB identification, the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the kit were 99.7%, 99.3%, 99.0% and 99.8%, respectively. For rifampicin-resistant MTB identification, the sensitivity, specificity, PPV, and NPV of the kit were 100.0%, 99.4%, 91.3%, and 100.0%, respectively, while the corresponding values of isoniazid-resistant MTB identification were 82.6%, 99.4%, 95.0%, and 97.6%, respectively. In identifying specific NTM species, the kit correctly identified 99.3% of M. abscessus (147/148) complex, 100% of M. fortuitum (32/32), M. gordonae (38/38), M. avium (39/39), M. intracellulare (90/90), M. kansasii (36/36), and M. avium complex species other than M. avium and M. intracellulare (94/94). In conclusions, the diagnostic value of the BluePoint MycoID plus kit was superior to culture method for recoveries and identification of NTM to species level. In addition, the diagnostic accuracy of BluePoint MycoID plus kit in MTB identification was similar to conventional culture method with high accuracy rate of rifampicin-resistant M. tuberculosis identification.

Topics: Drug Resistance, Multiple, Bacterial; Humans; Isoniazid; Mutation; Mycobacterium tuberculosis; Nontuberculous Mycobacteria; Reagent Kits, Diagnostic; Rifampin; Tuberculosis, Multidrug-Resistant

Multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains of Mycobacterium tuberculosis (TB) constitute a major public health concern.. To determine the timing of pncA mutations that confer pyrazinamide (PZA) resistance in relation to mutations conferring resistance to isoniazid (INH) and rifampicin (RMP).. Isolates from two major urban centres--Paris (101 strains) and Shanghai (171 strains)--were investigated for the association of pncA mutations with resistance to drugs other than PZA.. The proportion of pncA mutations found in INH-monoresistant strains was not increased.. pncA mutations associated with PZA resistance were found almost exclusively in MDR-TB strains, underlining the importance of determining PZA resistance when treating MDR- or XDR-TB.

Topics: Amidohydrolases; Antitubercular Agents; China; DNA Mutational Analysis; DNA, Bacterial; Drug Resistance, Multiple, Bacterial; Extensively Drug-Resistant Tuberculosis; Fluoroquinolones; Gene Frequency; Genotype; Humans; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Paris; Phenotype; Pyrazinamide; Rifampin; Tuberculosis, Multidrug-Resistant

The high cost of rifampicin-resistant tuberculosis (RR-TB) treatment hinders treatment access. South Africa has a high RR-TB burden, and national policy outlines decentralisation to improve access and reduce costs. We analysed health system costs associated with RR-TB treatment by drug resistance profile and treatment outcome in a decentralised programme.. Retrospective, routinely collected patient-level data were combined with unit cost data to determine costs for each patient in a cohort treated between January 2009 and December 2011. Drug costs were based on recommended regimens according to drug resistance and treatment duration. Hospitalisation costs were estimated based on admission/discharge dates, while clinic visit and diagnostic/monitoring costs were estimated according to recommendations and treatment duration. Missing data were imputed.. Among 467 patients (72% HIV infected), 49% were successfully treated. Treatment was initiated in primary care for 62%, with the remainder as inpatients. The mean cost per patient treated was $7916 (range 260-87,140), ranging from $5369 among patients who did not complete treatment to $23,006 for treatment failure. Mean cost for successful treatment was $8359 (2585-32,506). Second-line drug resistance was associated with a mean cost of $15,567 vs. $6852 for only first-line resistance, with the major cost difference due to hospitalisation. Costs are reported in 2013 USD.. RR-TB treatment cost was high and varied according to treatment outcome. Despite decentralisation, hospitalisation remained a significant cost, particularly among those with more extensive resistance and those with treatment failure. These cost estimates can be used to model the impact of new interventions to improve patient outcomes.

Topics: Adolescent; Adult; Aged; Antibiotics, Antitubercular; Child; Child, Preschool; Costs and Cost Analysis; Female; Health Care Costs; Hospitalization; Humans; Infant; Male; Middle Aged; Primary Health Care; Retrospective Studies; Rifampin; South Africa; Time Factors; Treatment Failure; Treatment Outcome; Tuberculosis, Multidrug-Resistant; Young Adult

Xpert MTB/RIF, the first automated molecular test for tuberculosis, is transforming the diagnostic landscape in high-burden settings. This study assessed the impact of up-front Xpert MTB/RIF testing on detection of pulmonary tuberculosis (PTB) and rifampicin-resistant PTB (DR-TB) cases in India.. This demonstration study was implemented in 18 sub-district level TB programme units (TUs) in India in diverse geographic and demographic settings covering a population of 8.8 million. A baseline phase in 14 TUs captured programmatic baseline data, and an intervention phase in 18 TUs had Xpert MTB/RIF offered to all presumptive TB patients. We estimated changes in detection of TB and DR-TB, the former using binomial regression models to adjust for clustering and covariates.. In the 14 study TUs, which participated in both phases, 10,675 and 70,556 presumptive TB patients were enrolled in the baseline and intervention phase, respectively, and 1,532 (14.4%) and 14,299 (20.3%) bacteriologically confirmed PTB cases were detected. The implementation of Xpert MTB/RIF was associated with increases in both notification rates of bacteriologically confirmed TB cases (adjusted incidence rate ratio [aIRR] 1.39; CI 1.18-1.64), and proportion of bacteriological confirmed TB cases among presumptive TB cases (adjusted risk ratio (aRR) 1.33; CI 1.6-1.52). Compared with the baseline strategy of selective drug-susceptibility testing only for PTB cases at high risk of drug-resistant TB, Xpert MTB/RIF implementation increased rifampicin resistant TB case detection by over fivefold. Among, 2765 rifampicin resistance cases detected, 1055 were retested with conventional drug susceptibility testing (DST). Positive predictive value (PPV) of rifampicin resistance detected by Xpert MTB/RIF was 94.7% (CI 91.3-98.1), in comparison to conventional DST.. Introduction of Xpert MTB/RIF as initial diagnostic test for TB in public health facilities significantly increased case-notification rates of all bacteriologically confirmed TB by 39% and rifampicin-resistant TB case notification by fivefold.

Topics: Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Female; Geography, Medical; Humans; India; Male; Microbial Sensitivity Tests; Molecular Diagnostic Techniques; Public Health Surveillance; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

This study aimed to evaluate the usefulness of the Xpert MTB/RIF assay for the rapid direct detection of M. tuberculosis complex (MTBC) strains and rifampicin resistance associated mutations in a resource-limited setting such as Guinea-Bissau and its implications in the management of tuberculosis (TB) and drug resistant tuberculosis, complementing the scarce information on resistance and genotypic diversity of MTBC strains in this West African country.. This cross-sectional prospective study included 100 consecutive TB patients with positive acid-fast smears at two months of anti-tuberculosis treatment or in a re-treatment situation, between May and December 2012. Resistance to rifampicin was detected using the GeneXpert system and the Xpert MTB/RIF assay. MTBC isolates obtained with the BACTEC MGIT 960 system were tested for susceptibility to first- and second-line anti-tuberculosis drugs. Overall, the prevalence of multidrug-resistant tuberculosis (MDR-TB) was found to be 9 cases. Of these, 67% (6 patients) of confirmed MDR-TB cases had no past history of TB treatment and 33% (3 patients) were previously treated cases. Extensively drug-resistant TB was not found. Molecular typing of the MDR-TB strains revealed recent transmission patterns of imported MDR strains.. The Xpert MTB/RIF assay was reliable for the detection of rifampicin resistant MTBC strains directly from sputum samples of patients undergoing first-line treatment for two months, being more trustworthy than the simple presence of acid-fast bacilli in the smear. Its implementation is technically simple, does not require specialized laboratory infrastructures and is suitable for resource-limited settings when a regular source of electricity and maintenance is available as well as financial and operation sustainability is guaranteed by the health authorities. A high prevalence of MDR-TB among patients at risk of MDR-TB after two months of first-line treatment was found, in support of the WHO recommendations for its use in the management of this risk group.

Topics: Adult; Antitubercular Agents; Cross-Sectional Studies; Female; Genotype; Guinea-Bissau; Humans; Male; Molecular Typing; Mutation; Mycobacterium tuberculosis; Patient Selection; Rifampin; Risk; Time Factors; Tuberculosis, Multidrug-Resistant

The current cost of Xpert MTB RIF (Xpert) consumables is such that algorithms are needed to select which patients to prioritise for testing with Xpert.. To evaluate two algorithms for prioritisation of Xpert in primary health care settings in a high TB and HIV burden setting.. Consecutive, presumptive TB patients with a cough of any duration were offered either Xpert or Fluorescence microscopy (FM) test depending on their CXR score or HIV status. In one facility, sputa from patients with an abnormal CXR were tested with Xpert and those with a normal CXR were tested with FM ("CXR algorithm"). CXR was scored automatically using a Computer Aided Diagnosis (CAD) program. In the other facility, patients who were HIV positive were tested using Xpert and those who were HIV negative were tested with FM ("HIV algorithm").. Of 9482 individuals pre-screened with CXR, Xpert detected TB in 2090/6568 (31.8%) with an abnormal CXR, and FM was AFB positive in 8/2455 (0.3%) with a normal CXR. Of 4444 pre-screened with HIV, Xpert detected TB in 508/2265 (22.4%) HIV positive and FM was AFB positive in 212/1920 (11.0%) in HIV negative individuals. The notification rate of new bacteriologically confirmed TB increased; from 366 to 620/ 100,000/yr and from 145 to 261/100,000/yr at the CXR and HIV algorithm sites respectively. The median time to starting TB treatment at the CXR site compared to the HIV algorithm site was; 1(IQR 1-3 days) and 3 (2-5 days) (p<0.0001) respectively.. Use of Xpert in a resource-limited setting at primary care level in conjunction with pre-screening tests reduced the number of Xpert tests performed. The routine use of Xpert resulted in additional cases of confirmed TB patients starting treatment. However, there was no increase in absolute numbers of patients starting TB treatment. Same day diagnosis and treatment commencement was achieved for both bacteriologically confirmed and empirically diagnosed patients where Xpert was used in conjunction with CXR.

Topics: Adult; Female; Health Facilities; Health Resources; HIV Infections; Humans; Male; Primary Health Care; Radiography, Thoracic; Reagent Kits, Diagnostic; Rifampin; Time Factors; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

The World Health Organization recommends diagnosing Multidrug-Resistant Tuberculosis (MDR-TB) in high burden countries by detection of mutations in Rifampin (RIF) Resistance Determining Region of Mycobacterium tuberculosis rpoB gene with rapid molecular tests GeneXpert MTB/RIF and Hain MTBDRplus. Such mutations are found in >95% of Mycobacterium tuberculosis strains resistant to RIF by conventional culture-based drug susceptibility testing (DST). However routine diagnostic screening with molecular tests uncovered specific "low level" rpoB mutations conferring resistance to RIF below the critical concentration of 1 μg/ml in some phenotypically susceptible strains. Cases with discrepant phenotypic (susceptible) and genotypic (resistant) results for resistance to RIF account for at least 10% of resistant diagnoses by molecular tests and urgently require new guidelines to inform therapeutic decision making. Eight strains with a "low level" rpoB mutation L511P were isolated by GHESKIO laboratory between 2008 and 2012 from 6 HIV-negative and 2 HIV-positive patients during routine molecular testing. Five isolates with a single L511P mutation and two isolates with double mutation L511P&M515T had MICs for RIF between 0.125 and 0.5 μg/ml and tested susceptible in culture-based DST. The eighth isolate carried a double mutation L511P&D516C and was phenotypically resistant to RIF. All eight strains shared the same spoligotype SIT 53 commonly found in Haiti but classic epidemiological investigation failed to uncover direct contacts between the patients. Whole Genome Sequencing (WGS) revealed that L511P cluster isolates resulted from a clonal expansion of an ancestral strain resistant to Isoniazid and to a very low level of RIF. Under the selective pressure of RIF-based therapy the strain acquired mutation in the M306 codon of embB followed by secondary mutations in rpoB and escalation of resistance level. This scenario highlights the importance of subcritical resistance to RIF for both clinical management of patients and public health and provides support for introducing rpoB mutations as proxy for MICs into laboratory diagnosis of RIF resistance. This study illustrates that WGS is a promising multi-purpose genotyping tool for high-burden settings as it provides both "gold standard" sequencing results for prediction of drug susceptibility and a high-resolution data for epidemiological investigation in a single assay.

Topics: Adolescent; Adult; Antitubercular Agents; Bacterial Proteins; Coinfection; Disease Outbreaks; DNA-Directed RNA Polymerases; Drug Resistance, Multiple, Bacterial; Female; Gene Expression; Genome, Bacterial; Genotype; Haiti; HIV Infections; Humans; Infant; Isoniazid; Male; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Tuberculosis is still one of the most important health problems in developing countries and increasing drug resistance is the main concern for its treatment. This study was designed to characterize the drug resistant Mycobacterium tuberculosis isolated from patients suffering from pulmonary tuberculosis in northeast of Iran.. In this cross-sectional study during 2012-2013, drug susceptibility testing was performed on Mycobacterium tuberculosis isolated in northeast of Iran using proportional method. Epidemiological data concerning these strains were also analyzed.. Among 125 studied isolates, 25 mycobacteria (20%) were diagnosed as nontuberculosis mycobacteria. Among the remaining 100 Mycobacterium tuberculosis isolates, the resistance rates were 7%, 7%, 3%, and 9% against isoniazid, rifampin, ethambutol, and streptomycin, respectively. Four isolates were resistant against both isoniazid and rifampin (MDR tuberculosis). The highest resistance rate was observed among 15-45-year-old patients. The MDR tuberculosis was much more prevalent among those who had previous history of treatment.. Considering these findings, DOTS strategy should be emphasized and promptly used in order to prevent further resistance. Regarding the high rate of nontuberculosis mycobacteria, it is recommended that confirmatory tests were performed before any therapeutic decision.

Topics: Adolescent; Adult; Drug Resistance; Ethambutol; Female; Humans; Iran; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Nontuberculous Mycobacteria; Rifampin; Tuberculosis, Multidrug-Resistant

Human P-glycoprotein (P-gp) is a membrane transporter encoded by ABCB1 (also known as MDR1) that plays a critical role in pharmacokinetics of many unrelated drugs. Rifampin (RMP) and ethambutol (ETB), two anti-tubercular agents, are substrates of P-gp. Single nucleotide polymorphisms (SNPs) in ABCB1 have been associated with resistance to several drugs; however, their association with RMP and ETB resistance in tuberculosis patients has not yet been studied. Genotype/allele frequencies in C1236T, G2677T/A and C3435T SNPs of ABCB1 were obtained from 99 tuberculosis patients susceptible or resistant to RMP and ETB (NoRER or RER). 2677G>A allele prevalence was found to be significantly higher in the RER group compared to NoRER (5 resistant vs 2 non-resistant patients, P < 0.01; OR, 11.0; 95% CI, 2.00-56.00). No differences were found in genotype/allele frequencies in C1236T and C3435T SNPs of ABCB1 and resistance to RMP and ETB in tuberculosis patients (P > 0.05). The present study suggests the 2677G>A allele of ABCB1 could be associated with simultaneous resistance to RMP and ETB in pulmonary tuberculosis patients. Further studies with larger sample sizes are needed to confirm this association and explore its nature.

Topics: Adult; Antitubercular Agents; ATP Binding Cassette Transporter, Subfamily B; Drug Resistance, Multiple, Bacterial; Ethambutol; Female; Gene Frequency; Genetic Association Studies; Haplotypes; Humans; Logistic Models; Male; Middle Aged; Odds Ratio; Phenotype; Polymorphism, Genetic; Rifampin; Risk Factors; Treatment Failure; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

In March 2012, the Xpert MTB/RIF assay (Xpert) was introduced in three provincial public hospitals in Indonesia as a novel diagnostic to detect tuberculosis and rifampicin resistance among high risk individuals.. This study assessed the effects of using Xpert in place of conventional solid and liquid culture and drug-susceptibility testing on case detection rates, treatment initiation rates, and health system delays among drug-resistant tuberculosis (TB) patients.. Cohort data on registration, test results and treatment initiation were collected from routine presumptive patient registers one year before and one year after Xpert was introduced. Proportions of case detection and treatment initiation were compared using the Pearson Chi square test and median time delays using the Mood's Median test.. A total of 975 individuals at risk of drug-resistant TB were registered in the pre-intervention year and 1,442 in the post-intervention year. After Xpert introduction, TB positivity rate increased by 15%, while rifampicin resistance rate reduced by 23% among TB positive cases and by 9% among all tested. Second-line TB treatment initiation rate among rifampicin resistant patients increased by 19%. Time from client registration to diagnosis was reduced by 74 days to a median of a single day (IQR 0-4) and time from diagnosis to treatment start was reduced by 27 days to a median of 15 days (IQR 7-51). All findings were significant with p<0.001.. Compared to solid and liquid culture and drug-susceptibility testing, Xpert detected more TB and less rifampicin resistance, increased second-line treatment initiation rates and shortened time to diagnosis and treatment. This test holds promise to improve rapid case finding and management of drug-resistant TB patients in Indonesia.

Topics: Adolescent; Adult; Aged; Antibiotics, Antitubercular; Child; Child, Preschool; Drug Resistance, Bacterial; Female; Humans; Indonesia; Infant; Infant, Newborn; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Population Surveillance; Rifampin; Tuberculosis, Multidrug-Resistant; Young Adult

The spread of multidrug-resistant tuberculosis (MDR-TB) strains has become a challenge to the global TB control and prevention program. In Ethiopia, particularly in rural areas, information on drug-resistant TB is very limited. In this study, we determined the drug resistance patterns of Mycobacterium tuberculosis (M. tuberculosis) isolates from pulmonary TB patients attending two public hospitals in the East Gojjam zone of northwest Ethiopia.. A cross-sectional study was conducted between May 2011 and January 2012 using Region of difference-9 (RD9) typing for the identification of species mycobacterium. Drug susceptibility testing (DST) of M. tuberculosis isolates to the first-line drugs: isoniazid, rifampicin, ethambutol and streptomycin was performed by the indirect proportion method on Middle brook 7H10 Agar media.. Out of 385 pulmonary TB suspects studied, 124 (32.2%) were culture positive among which 120 were M. tuberculosis strains. Susceptibility testing was performed for 89 isolates. Resistance to at least one drug was 15.58% ([12/77], 95% CI: 7.48-23.68) among newly diagnosed and 50.0% ([6/12], 95% CI: 21.71-78.29) among previously treated cases. Resistance among newly diagnosed patients was most common for streptomycin 5.19% (4/77) and ethambutol 5.19% (4/77) followed by rifampicin 3.89% (3/77). Among retreatment cases, isoniazid resistance was most frequent in which 33.33% (4/12) of the isolates were resistant. MDR prevalence was 1.29% (1/77) for newly diagnosed and 16.67% (2/12) for retreatment cases. In a multivariate logistic regression analysis, age group of 25-34 years (adjusted OR = 4.24; 95% CI: 1.02-17.5; P = 0.046) and previous history of treatment (adjusted OR = 5.42; 95% CI: 1.56-27.49; P = 0.01) were independently associated with anti-TB drug resistance.. In general, the magnitude of anti-TB drug resistance including MDR-TB was comparable to previous studies in other areas of Ethiopia. However, rifampicin resistance was high, which could suggest the potential for a rise in the incidence of MDR. Therefore, re-enforcing TB control programs should be considered by the concerned public health authorities.

Topics: Adolescent; Adult; Aged; Antitubercular Agents; Cross-Sectional Studies; Drug Resistance, Multiple, Bacterial; Ethambutol; Ethiopia; Female; Hospitals, Public; Humans; Isoniazid; Male; Middle Aged; Mycobacterium tuberculosis; Prevalence; Retreatment; Rifampin; Risk Assessment; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

To determine, in areas supported by BRAC, Bangladesh i) the pre-diagnosis and pre-treatment attrition among presumptive and confirmed Multi-Drug Resistant Tuberculosis (MDR-TB) patients and ii) factors associated with attrition.. This was a retrospective cohort study involving record review. Presumptive MDR-TB patients from peripheral microscopy centres serving 60% of the total population of Bangladesh were included in the study. Attrition and turnaround time for MDR-TB diagnosis by Xpert MTB/RIF and treatment initiation were calculated between July 2012 and June 2014.. Of 836 presumptive MDR-TB patients referred from 398 peripheral microscopy centres, 161 MDR-TB patients were diagnosed. The number of diagnosed MDR-TB patients was less than country estimates of MDR-TB patients (2000 cases) during the study period. Among those referred, pre-diagnosis and pre-treatment attrition was 17% and 21% respectively. Median turnaround time for MDR-TB testing, result receipt and treatment initiation was four, zero and five days respectively. Farmers (RR=2.3, p=0.01) and daily wage laborers (RR=2.1, p=0.04) had twice the risk of having pre-diagnosis attrition. Poor record-keeping and unreliable upkeep of presumptive MDR-TB patient databases were identified as challenges at the peripheral microscopy centres.. There was a low proportion of pre-diagnosis and pre-treatment attrition in patients with presumptive and confirmed MDR-TB under programmatic conditions. However, the recording and reporting system did not detect all presumptive MDR-TB patients, highlighting the need to improve the system in order to prevent morbidity, mortality and transmission of MDR-TB in the community.

Topics: Adolescent; Adult; Aged; Antibiotics, Antitubercular; Bangladesh; Cohort Studies; Female; Humans; Male; Middle Aged; Patient Dropouts; Retrospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant; Young Adult

The prevalence of multidrug-resistant tuberculosis (TB) among new and retreatment cases in 2011 in Ethiopia was 2.7% and 17.9%, respectively. However, data on heteroresistance and gene mutation profiles of Mycobacterium tuberculosis were not documented.. A cross-sectional study was conducted on 413 TB-positive clinical specimens submitted between 2012 and 2014 to Bahir Dar Regional Laboratory Center for confirmation of multidrug resistance. Resistance determining genes were analyzed using a line probe assay.. Of 413M. tuberculosis isolates, 150 (36.3%) were multidrug-resistant, 19 (4.6%) were resistant only to rifampicin, and 26 (6.3%) were resistant to isoniazid. Of 169 rifampicin-resistant and 176 isoniazid-resistant isolates, only eight (4.7%) showed rifampicin heteroresistance and only two (1.13%) showed isoniazid heteroresistance. Failing of the rpoB WT8 gene with corresponding hybridization of rpoB MUT3 (S531L substitution) accounted for 85 (50.3%) rifampicin-resistant mutations. Among 176 isoniazid-resistant isolates, 155 (88.1%) strains had the Ser315Thr1 substitution.. The prevalence of multidrug-resistant M. tuberculosis was high in the study area. Ser531Leu and Ser315Thr1 substitutions were the highest gene mutations for rifampicin and isoniazid, respectively.

Topics: Adolescent; Adult; Antitubercular Agents; Cross-Sectional Studies; Drug Resistance, Multiple, Bacterial; Ethiopia; Female; Genes, Bacterial; Humans; Isoniazid; Male; Middle Aged; Mutation; Mycobacterium tuberculosis; Prevalence; Rifampin; Tuberculosis, Multidrug-Resistant; Young Adult

Multidrug resistant tuberculosis(MDR-TB) is becoming a major threat to tuberculosis control programs in Ethiopia.. To determine risk factors of MDR-TB patients in Amhara National Regional State, Ethiopia.. Case-control study was conducted from May 2013 to January 2014. Resistance to rifampicin and isoniazid were done molecularly using line probe assay. TB patients infected with MDR-M.tuberculosis and non MDR-M.tuberculosis strain were considered as cases and controls, respectively. Data was collected using structured questionnaire with face to face interview. Patients' clinical record review was also done.Multivariate analysis was computed to determine the risk factors of MDR-TB.. A total of 153 MDR-TB and equal number of non MDR-TB patients' participated in the study. Patients who had TB treatment failure (AOR=13.5,CI=2.69-70), cavitations on chest x-ray (AOR=1.9,CI=1.1-3.38) and contact with MDR-TB patients (AOR=1.4,CI=0.19-0.39) were more likely to be MDR-TB patients. Low monthly income (AOR=1.1,CI=0.34-0.47),alcohol consumption (AOR=1.5,CI=0.2-0.98) and young age (AOR=2.9,CI=1.07-7.68) were the other risk factors of MDR-TB.. TB treatment failure, cavitation on chest X-ray, contact with MDR-TB patients and low socioeconomic status were important risk factors for development of MDR-TB. Therefore, strict adherence to directly observed therapy, appropriate management of TB patients and advice on the value of nutrients are helpful to control the spreading of MDR-TB.

Topics: Adolescent; Adult; Antitubercular Agents; Case-Control Studies; Directly Observed Therapy; Ethiopia; Female; Humans; Income; Isoniazid; Male; Middle Aged; Multivariate Analysis; Patient Compliance; Rifampin; Treatment Failure; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

Resistance to Mycobacterium tuberculosis is a reality worldwide, and its diagnosis continues to be difficult and time consuming. To face this challenge, the World Health Organization has recommended the use of rapid molecular tests. We evaluated the routine use (once a week) of a line probe assay (Genotype MTBDRplus) for early diagnosis of resistance and for assessment of the main related risk factors over 2 years. A total of 170 samples were tested: 15 (8.8%) were resistant, and multidrug resistance was detected in 10 (5.9%). The sensitivity profile took 3 weeks (2 weeks for culture and 1 week for rapid testing). Previous treatment for tuberculosis and the persistence of positive acid-fast smears after 4 months of supervised treatment were the major risk factors observed. The use of molecular tests enabled early diagnosis of drug-resistant bacilli and led to appropriate treatment of the disease. This information has the potential to interrupt the transmission chain of resistant M. tuberculosis.

Topics: Adult; Antitubercular Agents; Bacteriological Techniques; Brazil; DNA, Bacterial; Early Diagnosis; Female; Genotyping Techniques; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Risk Factors; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

Topics: Antimicrobial Cationic Peptides; Cathelicidins; Guanine; Helicobacter Infections; Hepatitis B; Humans; Isoniazid; Rifampin; Tuberculosis, Multidrug-Resistant

Topics: Adult; Aged; Antitubercular Agents; Female; Humans; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Mutation; Mycobacterium tuberculosis; Prospective Studies; Rifampin; Tuberculosis, Multidrug-Resistant

Rapid but simple diagnostic tools for the detection of drug-resistant (DR) tuberculosis (TB) have been acknowledged as being important for its effective management and control.. To establish a molecular line-probe assay (GenoType MTBDRplus) for detecting DR-TB in Ghana.. We first screened 113 Mycobacterium tuberculosis isolates using the indirect proportion method and MTBDRplus. The rpoB and katG genes and the promoter regions of oxyR-ahpC and inhA were sequenced to identify mutations in isolates found to be resistant on phenotypic drug susceptibility testing and/or MTBDRplus. We then analysed an additional 412 isolates using only MTBDRplus.. Respectively 43 (8.2%) and 8 (1.5%) isolates were resistant to isoniazid (INH) and rifampicin (RMP), while 8 (1.5%) were multidrug-resistant. In resistant isolates, mutations in codon 450 of rpoB and codon 315 of katG, conferring resistance to respectively RMP and INH, dominated. We found two RMP-resistant isolates with a S450L substitution, each harbouring an additional mutation at S388L and Q409R. Using phenotypic testing as gold standard, the MTBDRplus assay showed a sensitivity and specificity in the detection of RMP and INH resistance and multidrug resistance of respectively 100% and 100%, 83.3% and 100%, and 100% and 100%.. The high sensitivity of MTBDRplus makes it a valuable addition to the conventional TB diagnostic algorithm in Ghana.

Topics: Antitubercular Agents; Cross-Sectional Studies; Drug Resistance, Multiple, Bacterial; Ghana; Humans; Isoniazid; Microbial Sensitivity Tests; Molecular Diagnostic Techniques; Mutation; Mycobacterium tuberculosis; Phenotype; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Rapid detection of mycobacterium tuberculosis (MTB) resistance is a key step in the control of disease. This study aimed to identify the prevalence and accuracy of isoniazid (INH) and rifampin (RMP) resistance and their risk factors using multiplex allele-specific polymerase chain reaction (MAS-PCR) to detect such mutations.. In this cross-sectional study (2012-2013), 257 MTB patients from five frontier border provinces of Iran were selected and after divulging a full clinical history and undergoing a physical evaluation, the accuracy of drug resistance detection was carried out using the standard proportion test, sequencing, and GeneXpert/rifampicin (RIF) technique. Full demographic and environmental histories were evaluated.. The overall frequency of mutations was 34. Frequency of patients with mutations in KatG315 and at least one rpoB codon (of 516, 526, and 531 codons) were seven cases (2.7%). In comparison to the standard proportion test, the sensitivity and specificity of MAS-PCR in detecting common INH-resistant mutations were 68.75 and 100%, and in the detection of common RMP-resistant mutation were 81.8 and 100%, respectively. Also, 88.89% of KatG 315 mutations and 100% of rpoB mutations were diagnosed and compared with DNA sequencings. Compared to GeneXpert/RIF, 100% of RMP common point mutation was determined by MAS-PCR. Mutation odds were higher in males and greater in those with a history of anti-tuberculosis treatment.. The results of this study indicated that MAS-PCR is an efficient method for rapid detection of mutations leading to RMP resistance but merely to KatG it is not satisfactory for the detection of INH resistance. Accurate and rapid detection of drug resistance is crucial in males and patients with a history of tuberculosis.

Topics: Adult; Aged; Bacterial Proteins; Catalase; Cross-Sectional Studies; DNA-Directed RNA Polymerases; Female; Humans; Iran; Isoniazid; Male; Middle Aged; Multiplex Polymerase Chain Reaction; Mutation; Mycobacterium tuberculosis; Prevalence; Rifampin; Risk Factors; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant

In order to evaluate the performance of a molecular Hain line probe assay (Hain LPA) for rapid detection of rifampicin and isoniazid resistance of Mycobacterium tuberculosis in China, 1612 smear positive patients were consecutively enrolled in this study. Smear positive sputum specimens were collected for Hain LPA and conventional drug susceptibility testing (DST). The sensitivity and specificity of Hain LPA were analyzed by using conventional DST as golden reference. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for rifampicin resistance detection were 88.33%, 97.66%, 81.54%, and 98.62%, respectively. The sensitivity, specificity, PPV and NPV for isoniazid resistance detection were 80.25%, 98.07%, 87.25%, and 96.78%, respectively. These findings suggested that Hain LPA can be an effective method worthy of broader use in China.

Topics: China; Genotyping Techniques; Humans; Isoniazid; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Xpert MTB/RIF (Xpert) was piloted in Kazakhstan to detect tuberculosis (TB) and rifampicin resistance (RR-)TB among individuals at risk of multidrug-resistant (MDR-) TB. This study assessed the performance of Xpert compared to conventional diagnostic methods, RR-TB case detection among various risk groups, treatment initiation and time to diagnosis and treatment.. Eligible individuals were tested with Xpert, smear microscopy, culture and drug-susceptibility testing (DST) at the national TB reference laboratory and three provincial laboratories. Data was collected prospectively from August 2012 to May 2013 from routine laboratory and treatment registers.. A total of 5,611 Xpert tests were performed mostly targeting contacts of MDR-TB patients, 'other' presumptive MDR-TB patients, and retreatment cases (26%, 24% and 22%, respectively). Compared to phenotypic DST, the positive predictive value of Xpert to detect RR-TB was 93.1% and 96.4% and the negative predictive value was 94.6% and 92.7% using solid and liquid culture media, respectively. RR-TB detection was highest among (former) prisoners, retreatment cases, people living with HIV/AIDS (PLWHA), and TB patients with positive smears after intensive phase of treatment (59%, 58%, 54% and 53% among TB positives, respectively). 88.9% of RR-TB patients were registered to have started second-line TB treatment. Median time to diagnosis with Xpert was 0.0 days (IQR 0.0-1.0), time from diagnosis to start of first-line treatment 3.0 days (IQR 1.0-7.0), and to start of second-line treatment 7.0 days (IQR 4.0-16).. Compared to conventional culture and DST, Xpert had a shorter result turn-around-time and excellent concordance to detect RR-TB. Time from sputum collection to start of second-line treatment was reduced to one week. The yield of Xpert could be maximized by increasing referrals from penitentiary and HIV centers to TB centers.

Topics: Antibiotics, Antitubercular; Bacterial Typing Techniques; Drug Resistance, Bacterial; Female; Humans; Kazakhstan; Male; Mycobacterium tuberculosis; Prospective Studies; Reagent Kits, Diagnostic; Rifampin; Sensitivity and Specificity; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

To examine the impact of immigrant populations on the epidemiology of tuberculosis in Hong Kong.. Longitudinal cohort study.. Hong Kong.. Socio-demographic and disease characteristics of all tuberculosis notifications in 2006 were captured from the statutory tuberculosis registry and central tuberculosis reference laboratory. Using 2006 By-census population data, indirect sex- and age-standardised incidence ratios by place of birth were calculated. Treatment outcome at 12 months was ascertained from government tuberculosis programme record forms, and tuberculosis relapse was tracked through the notification registry and death registry up to 30 June 2013.. Moderately higher sex- and age-standardised incidence ratios were observed among various immigrant groups: 1.06 (Mainland China), 2.02 (India, Pakistan, Bangladesh), 1.59 (Philippines, Thailand, Indonesia, Nepal), and 3.11 (Vietnam). Recent Mainland migrants had a lower sex- and age-standardised incidence ratio (0.51 vs 1.09) than those who immigrated 7 years ago or earlier. Age younger than 65 years, birth in the Mainland or the above Asian countries, and previous treatment were independently associated with resistance to isoniazid and/or rifampicin. Older age, birth in the above Asian countries, non-permanent residents, previous history of treatment, and resistance to isoniazid and/or rifampicin were independently associated with poor treatment outcome (other than cure/treatment completion) at 1 year. Birth outside Hong Kong was an independent predictor of relapse following successful completion of treatment (adjusted hazard ratio=1.76; 95% confidence interval, 1.07-2.89; P=0.025).. Immigrants carry with them a higher tuberculosis incidence and/or drug resistance rate from their place of origin. The higher drug resistance rate, poorer treatment outcome, and excess relapse risk raise concern over secondary transmission of drug-resistant tuberculosis within the local community.

Topics: Adolescent; Adult; Age Distribution; Aged; Antitubercular Agents; Asia, Southeastern; Asia, Western; Child; Child, Preschool; China; Emigrants and Immigrants; Female; Hong Kong; Humans; Incidence; Infant; Infant, Newborn; Isoniazid; Longitudinal Studies; Male; Middle Aged; Population Surveillance; Recurrence; Registries; Rifampin; Sex Distribution; Tuberculosis; Tuberculosis, Multidrug-Resistant; Young Adult

We aimed to characterize the genetic diversity of drug-resistant Mycobacterium tuberculosis (MTb) clinical isolates and investigate the molecular epidemiology of multidrug-resistant (MDR) tuberculosis from Minas Gerais State, Brazil.. One hundred and four MTb clinical isolates were assessed by IS6110-RFLP, 24-locus mycobacterial interspersed repetitive units variable-number tandem repeats (MIRU-VNTR), TB-SPRINT (simultaneous spoligotyping and rifampicin-isoniazid drug-resistance mutation analysis) and 3R-SNP-typing (analysis of single-nucleotide polymorphisms in the genes involved in replication, recombination and repair functions).. Fifty-seven different IS6110-RFLP patterns were found, among which 50 had unique patterns and 17 were grouped into seven clusters. The discriminatory index (Hunter and Gaston, HGDI) for RFLP was 0.9937. Ninety-nine different MIRU-VNTR patterns were found, 95 of which had unique patterns and nine isolates were grouped into four clusters. The major allelic diversity index in the MIRU-VNTR loci ranged from 0.6568 to 0.7789. The global HGDI for MIRU-VNTR was 0.9991. Thirty-two different spoligotyping profiles were found: 16 unique patterns (n = 16) and 16 clustered profiles (n = 88). The HGDI for spoligotyping was 0.9009. The spoligotyped clinical isolates were phylogenetically classified into Latin-American Mediterranean (66.34 %), T (14.42 %), Haarlem (5.76 %), X (1.92 %), S (1.92 %) and U (unknown profile; 8.65 %). Among the U isolates, 77.8 % were classified further by 3R-SNP-typing as 44.5 % Haarlem and 33.3 % LAM, while the 22.2 % remaining were not classified. Among the 104 clinical isolates, 86 were identified by TB-SPRINT as MDR, 12 were resistant to rifampicin only, one was resistant to isoniazid only, three were susceptible to both drugs, and two were not successfully amplified by PCR. A total of 42, 28 and eight isolates had mutations in rpoB positions 531, 526 and 516, respectively. Correlating the cluster analysis with the patient data did not suggest recent transmission of MDR-TB.. Although our results do not suggest strong transmission of MDR-TB in Minas Gerais (using a classical 100 % MDR-TB identical isolates cluster definition), use of a smoother cluster definition (>85 % similarity) does not allow us to fully eliminate this possibility; hence, around 20-30 % of the isolates we analyzed might be MDR-TB transmission cases.

Topics: Alleles; Antitubercular Agents; Bacterial Proteins; Brazil; Cluster Analysis; DNA-Directed RNA Polymerases; DNA, Bacterial; Genetic Variation; Genotype; Humans; Isoniazid; Minisatellite Repeats; Mycobacterium tuberculosis; Phylogeny; Polymerase Chain Reaction; Polymorphism, Genetic; Rifampin; Tuberculosis, Multidrug-Resistant

A 9-year-old HIV-infected child previously treated with inadequate doses of antitubercular drugs based on weight was admitted 5 months after initial tuberculosis (TB) diagnosis with acute hemiplegia and inguinal lymphadenopathies in a rural hospital in Tanzania. He was diagnosed with TB meningitis and lymphadenitis using Xpert Mycobacterium tuberculosis/rifampicin (MTB/RIF) assay. Rifampicin resistance was detected in the lymph node aspirate but not in the cerebrospinal fluid. His TB therapy was optimised based on available medications and antiretroviral treatment was initiated 6 weeks later. Despite these efforts, the clinical evolution was poor and the child died 12 weeks after admission.

Topics: Anti-HIV Agents; Antibiotics, Antitubercular; Child; DNA, Bacterial; Drug Resistance, Bacterial; Fatal Outcome; Hemiplegia; HIV Infections; Humans; Lymph Nodes; Lymphadenitis; Male; Meningitis; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

We evaluated the performance of the molecular lab-on-chip-based VerePLEX Biosystem for detection of multidrug-resistant tuberculosis (MDR-TB), obtaining a diagnostic accuracy of more than 97.8% compared to sequencing and MTBDRplus assay for Mycobacterium tuberculosis complex and rifampin and isoniazid resistance detection on clinical isolates and smear-positive specimens. The speed, user-friendly interface, and versatility make it suitable for routine laboratory use.

Topics: Antitubercular Agents; Drug Resistance, Multiple, Bacterial; Humans; Isoniazid; Lab-On-A-Chip Devices; Molecular Diagnostic Techniques; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

Despite the widespread introduction of Xpert(®) MTB/RIF in developing countries, reports of its use and value in routine conditions remain limited.. To describe Xpert results in relation to microscopy, treatment initiation, cost and workload under routine conditions at four sites in Cambodia, Georgia, Kenya and Swaziland.. Laboratory and clinical information on presumed TB patients were obtained from routine registers over a period of at least 6 months between March and November 2012.. Among the 6086 presumed TB patients included in the analysis, Xpert testing increased the number of biologically confirmed cases by 15% to 67% compared to microscopy. Up to 12% of the initial Xpert results were inconclusive. Between 56% and 83% of patients were started on treatment based on microscopy and/or Xpert results, with median delays of 1-16 days. Rifampicin resistance was detected in 3-19% of Xpert-positive patients.. Despite the additional numbers of cases detected by Xpert compared to microscopy, large proportions of patients are still started on treatment empirically in routine practice. Patient and specimen flow should be optimised to reduce delays in treatment initiation. Simple, non-sputum-based point-of-care tests with high sensitivity are needed to improve TB diagnosis and management.

Topics: Adolescent; Adult; Aged; Antibiotics, Antitubercular; Cambodia; Child; Child, Preschool; Diagnostic Tests, Routine; Drug Resistance, Bacterial; Eswatini; Female; Georgia; HIV Infections; Humans; Kenya; Male; Middle Aged; Molecular Diagnostic Techniques; Mycobacterium tuberculosis; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Genotyping of Mycobacterium tuberculosis helps to understand the molecular epidemiology of tuberculosis and to address evolutionary questions about the disease spread. Certain genotypes also have implications for the spread of infection and treatment. Indonesia is a very diverse country with a population with multiple ethnicities and cultures and a history of many trade and tourism routes. This study describes the first attempt to map the molecular epidemiology of TB in the Indonesian archipelago.. From 2008 to 2011, 404 clinical specimens from sputum-smear (SS+) TB patients, age ≥15 years, were collected from 16 TB referral primary health centers (PHC) in 16 provincial capitals in Indonesia. Susceptibility testing to first line drugs was conducted for 262 samples using the agar proportion method as per WHO guidelines. Spoligotyping was done on all samples.. Ninety-three of the 404 samples (23 %) were from the Beijing family, making it the predominant family in the country. However, the geographic distribution of the family varied by region with 86/294 (29.3 %) in the western region, 6/72 (8.3 %) in the central region, and 2/72 (2.8 %) in the eastern region (p < 0.001). The predominant genotype in the central and eastern regions was from the East-African-Indian (EAI) family, comprising 15.3 % (11/72), and 26.3 % (10/38) of the isolates, respectively. Drug susceptibility to first-line anti-TB drugs was tested in 262 isolates. 162 (61.8 %) isolates were susceptible to all TB drugs, 70 (26.7 %) were mono-resistant 16 (6.1 %) were poly-resistant, and 14 (5.4 %) were multi-drug resistant (MDR). The proportion of Beijing family isolates in the susceptible, mono-resistant, poly-resistant, and MDR groups was 33/162 (20.4 %), 28/70 (40.0 %), 6/16 (37.5 %), and 3/14 (21.4 %), respectively. Overall, resistance of the Beijing family isolates to any of the first line TB drugs was significantly higher than non-Beijing families [37/71 (52.1 %) vs. 63/191 (33.0 %) (p-value = 0.003)].. The distribution of Mycobacterium tuberculosis genotypes in Indonesia showed high genetic diversity and tended to vary by geographic regions. Drug susceptibility testing confirmed that the Beijing family of M.tb in Indonesia exhibited greater resistance to first line anti-TB drugs than did other families.

Topics: Adolescent; Adult; Aged; Anti-Bacterial Agents; Antitubercular Agents; Ethambutol; Female; Genetic Variation; Genotype; Humans; Indonesia; Isoniazid; Male; Microbial Sensitivity Tests; Middle Aged; Molecular Epidemiology; Mycobacterium tuberculosis; Rifampin; Sputum; Streptomycin; Tuberculosis; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

Drug-resistant TB poses a major threat to control of TB worldwide. Despite progress in the detection of Multidrug-resistant TB (MDR-TB) cases, a major diagnostic gap remains: 55% of reported TB patients estimated to have MDR-TB were not detected in 2013. MDR-TB antigens were conjugated to CNBr-activated Sepharose 4B. Specific polyclonal antibodies against MDR-TB Ags were prepared in rabbits using two boosted injections of the MDR-TB antigen. The antibodies were purified and treated with susceptible TB to remove any non-specific and cross-reactive antibodies. In the present study, comparative analysis of electrophoretic pattern of different antigens of INH/RIF-resistant TB were studied for identifying protein profiles. A RIF-resistant TB antigen was shown here to have different protein profiles from INH-resistant TB isolate. The results of Western blotting analysis showed that in the RIF- and INH-resistant antigenic fractions some bands of 14.4 and 45 kDa as immunogenic were common. Moreover, four bands of RIF-resistant TB antigen fractions (16, 19, 21, and 45 KDa) and one band of INH-resistant TB (about 26 KDa) were detected as diagnostic antigens. This study suggests that the Western blot is an accurate test to survey INH- and RIF-resistant TB antigens of M. tuberculosis infection. These findings indicate that MDR-TB diagnosis (based on Ag detection) could be useful in the identification of disease stages that precede symptomatic and microbiologically positive TB, such as subclinical and incipient TB.

Topics: Animals; Antibodies, Bacterial; Antigens, Bacterial; Antitubercular Agents; Blotting, Western; Humans; Isoniazid; Molecular Weight; Mycobacterium tuberculosis; Rabbits; Rifampin; Tuberculosis, Multidrug-Resistant

Multidrug-resistant tuberculosis is a major issue worldwide; however, accessibility to drug susceptibility testing (DST) is still limited in developing countries, owing to high costs and complexity. We developed a proportion method on 12-well microplates for DST. The assay reduced the time to results to <12 days and <10 days when bacterial growth was checked with the naked eye or a microscope, respectively. Comparison with the Canetti-Grosset method showed that the results of the two assays almost overlapped (kappa index 0.98 (95% CI 0.91-1.00) for isoniazid, rifampicin, streptomycin; and kappa index 0.92 (95% CI 0.85-0.99) for ethambutol). The sequencing of genes involved in drug resistance showed similar level of phenotype-genotype agreement between techniques. Finally, measurement of the MICs of rifampicin and ethambutol suggests that the currently used critical ethambutol concentration should be revised, and that the current molecular drug susceptibility tests for rifampicin need to be re-evaluated, as in vitro rifampicin-sensitive isolates could harbour drug resistance-associated mutation(s).

Topics: Agar; Antitubercular Agents; Disease Susceptibility; Drug Resistance, Multiple, Bacterial; Ethambutol; Genes, Bacterial; Humans; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant

The South African Electronic Drug-Resistant Tuberculosis Register (EDRweb) is the national database of registered drug-resistant tuberculosis (DR-TB) cases.. This study was a retrospective, de-identified secondary analysis of EDRweb patients initiating treatment for rifampicin-resistant TB (January 2009 to September 2011). The relative risks of death and treatment success were estimated using modified Poisson regression with robust error estimation.. Seventeen thousand six hundred and ninety-seven cases of DR-TB were registered and met the inclusion criteria; 52.0% (n=9207) were male and the median age was 35 years (interquartile range 27-43 years). Of the 9419 cases with HIV infection (53.2%), 7157 (76.0%) were on antiretroviral therapy. Most had undergone previous TB treatment (76.5%, n=13531). Multidrug-resistant TB was the most common diagnosis, at 80.6% (n=14272). No treatment outcome was available for 6934 patients (39.2%). For patients with outcomes, 4227 (39.4%) were successfully treated, 2987 (27.8%) died, 2533 (23.7%) were lost to follow-up, and 996 (9.3%) failed. Second-line drug resistance was the strongest predictor of death during DR-TB treatment; extensively drug-resistant TB patients were more likely to have died during treatment (adjusted relative risk 2.63, 95% confidence interval 2.45-2.84).. Testing for second-line drug resistance at initiation of DR-TB treatment can identify patients most at risk of treatment failure and death and most in need of individualized treatment.

Topics: Adolescent; Adult; Antitubercular Agents; Cohort Studies; Female; HIV Infections; Humans; Male; Middle Aged; Registries; Retrospective Studies; Rifampin; Treatment Outcome; Tuberculosis; Tuberculosis, Multidrug-Resistant; Young Adult

This report describes the evaluation of the novel MTB-DR-RIF 9G test for the accurate detection and discrimination of Mycobacterium tuberculosis (MTB) and rifampicin-resistant M. tuberculosis (MTB-DR-RIF) in the clinical samples. The procedure included the amplification of a nucleotide fragment of the rpoB gene of the MTB and MTB-DR-RIF strains and their hybridization with the immobilized probes. The MTB-DR-RIF 9G test was evaluated for its ability to detect and discriminate MTB and MTB-DR-RIF strains in 113 known clinical samples. The accuracy of the MTB-DR-RIF 9G test was determined by comparing its results with sequencing analysis and drug susceptibility testing. The sensitivity and specificity of the MTB-DR-RIF 9G test at 95% confidence interval were found to be 95.4% (89.5-98.5) and 100% (69.2-100), respectively. The positive predictive value and negative predictive value of the MTB-DR-RIF 9G test at 95% confidence interval were found to be 100% (85.0-95.9) and 66.7% (38.4-88.18), respectively. Sequencing analysis of all samples indicated that the mutations present in the regions identified with the MTB-DR-RIF 9G assay can be detected accurately.

Topics: Antibiotics, Antitubercular; Bacterial Proteins; Bacteriological Techniques; Diagnosis, Differential; Discriminant Analysis; DNA Mutational Analysis; DNA-Directed RNA Polymerases; DNA, Bacterial; Drug Resistance, Multiple, Bacterial; Humans; Molecular Diagnostic Techniques; Mutation; Mycobacterium tuberculosis; Nucleic Acid Hybridization; Polymerase Chain Reaction; Polymorphism, Single Nucleotide; Predictive Value of Tests; Reproducibility of Results; Rifampin; Tuberculosis; Tuberculosis, Multidrug-Resistant

Drug-resistant tuberculosis (TB) is an important public health problem in Lithuania with MDR rates in new cases reaching 11% in 2012. Currently available diagnostic tools are not fully adequate for an accurate and rapid result for diagnosis of TB and MDR-TB.. To evaluate the performance of Xpert(®) MTB/RIF assay for an early diagnosis of TB and detection of rifampicin (RIF) resistance in routine settings in Lithuania.. A total of 833 individual respiratory samples obtained from patients previously treated for TB and MDR-TB contacts were tested using the Xpert MTB/RIF assay. Performance characteristics of the assay for TB and RIF resistance detection were calculated using culture and phenotypical DST results as a gold standard.. The overall sensitivity and specificity of the Xpert MTB/RIF assay for TB detection were 93.7% and 91.7%, respectively with the sensitivity for smear-negative specimens reaching 82.5%. Resistance to RIF was detected in 81 (20.7%) primary specimens with no false negative results; there were 4/225 (1.8%) false-positives among strains sensitive to rifampicin. Overall sensitivity and specificity of the molecular assay for detection of RIF resistance calculated against phenotypic DST results were 100% and 98.2%, respectively.. Our results demonstrate very good performance of the Xpert MTB/RIF assay for the detection of TB and RIF resistance on primary respiratory specimens. It provides strong evidence that implementation of the assay for routine laboratory diagnosis in high drug-resistance settings may improve and facilitate TB diagnosis.

Topics: Adult; Antibiotics, Antitubercular; Early Diagnosis; Female; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Mycobacterium tuberculosis; Point-of-Care Systems; Polymerase Chain Reaction; Retrospective Studies; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Vietnam is ranked 14(th) among 27 countries with high burden of multidrug-resistant tuberculosis (MDR-TB). In 2009, the Vietnamese government issued a policy on MDR-TB called Programmatic Management of Drug-resistant Tuberculosis (PMDT) to enhance and scale up diagnosis and treatment services for MDR-TB. Here we assess the PMDT performance in 2013 to determine the challenges to the successful identification and enrollment for treatment of MDR-TB in Vietnam.. In 35 provinces implementing PMDT, we quantified the number of MDR-TB presumptive patients tested for MDR-TB by Xpert MTB/RIF and the number of MDR-TB patients started on second-line treatment. In addition, existing reports and documents related to MDR-TB policies and guidelines in Vietnam were reviewed, supplemented with focus group discussions and in-depth interviews with MDR-TB key staff members.. 5,668 (31.2 %) of estimated 18,165 MDR-TB presumptive cases were tested by Xpert MTB/RIF and second-line treatment was provided to 948 out of 5100 (18.7 %) of MDR-TB patients. Those tested for MDR-TB were 340/3224 (10.5 %) of TB-HIV co-infected patients and 290/2214 (13.1 %) of patients who remained sputum smear-positive after 2 and 3 months of category I TB regimen. Qualitative findings revealed the following challenges to detection and enrollment of MDR-TB in Vietnam: insufficient TB screening capacity at district hospitals where TB units were not available and poor communication and implementation of policy changes. Instructions for policy changes were not always received, and training was inconsistent between training courses. The private sector did not adequately report MDR-TB cases to the NTP.. The proportion of MDR-TB patients diagnosed and enrolled for second-line treatment is less than 20 % of the estimated total. The low enrollment is largely due to the fact that many patients at risk are missed for MDR-TB screening. In order to detect more MDR-TB cases, Vietnam should intensify case finding of MDR-TB by a comprehensive strategy to screen for MDR-TB among new cases rather than targeting previously treated cases, in particular those with HIV co-infection and contacts of MDR-TB patients, and should engage the private sector in PMDT.

Topics: Coinfection; Communication; Disease Management; Focus Groups; Health Policy; HIV Infections; Humans; Mass Screening; Mycobacterium tuberculosis; Private Sector; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Vietnam

Tuberculosis (TB) is a serious communicable disease throughout the world. Re-emergence of the TB epidemic is aggravated by the circulation of multidrug-resistant Mycobacterium tuberculosis strains, and more than half of new cases have occurred in Asia. Therefore, it is important to understand the gene mutations underlying the development of rifampicin resistance in Asia.. In this study, we classified the rifampicin-resistant Mycobacterium tuberculosis (MTB) rpoB data downloaded from Genbank, based on 12 mutation points. The relationship between the mutation sites and regional information was analyzed, after which the mutation dates and mutation trends of the rpoB gene were predicted by the Markov Chain Monte Carlo (MCMC) method.. We discovered that the mutation sites of the rpoB gene were disparate in different regions of Asia. The results of this study clearly showed that drug-resistant gene mutations in Asia started to increase in 2000 and peaked in 2006, indicating the relationship between drug resistance and outbreak trends of TB.. From our analysis, it was not difficult to see the relationship between the mutation rates of the rpoB gene and the outbreak of TB. Hence, to some degree, outbreak trends of TB can be predicted through genotyping based on the rpoB gene.

Topics: Antibiotics, Antitubercular; Asia; Bacterial Proteins; Bayes Theorem; Databases, Genetic; DNA-Directed RNA Polymerases; Drug Resistance, Bacterial; Evolution, Molecular; Humans; Markov Chains; Models, Genetic; Monte Carlo Method; Mutation; Mycobacterium tuberculosis; Phylogeny; Population Dynamics; Rifampin; Tuberculosis, Multidrug-Resistant

The Xpert(®) MTB/RIF assay is endorsed by the World Health Organization for the detection of rifampicin (RMP) resistant tuberculosis (TB).. To evaluate Xpert for its diagnostic accuracy in detecting RMP-resistant TB and its impact on treatment outcomes.. Patients with available phenotypic drug susceptibility testing (DST) results and those in whom RMP-resistant pulmonary TB was diagnosed using Xpert were evaluated. The accuracy and turnaround time (TAT) of Xpert for determining RMP-resistant TB was calculated. The TATs for treatment between patients diagnosed with RMP-resistant TB using Xpert and those diagnosed without the assay (phenotypic DST group) were compared.. In 321 patients, when phenotypic DST was used as the gold standard, Xpert sensitivity and specificity for RMP resistance diagnosis was respectively 100% and 98.7%; the positive and negative predictive values were respectively 86.2% and 100%. The Xpert group had a much shorter interval from initial evaluation to commencing second-line anti-tuberculosis treatment (64 vs. 2 days, P < 0.001), and negative conversion of mycobacterial cultures (197 vs. 62.5 days, P < 0.001) than the phenotypic DST group.. Xpert was accurate at diagnosing RMP resistance in this setting with an intermediate TB burden and a low level of RMP resistance. Xpert might reduce disease transmission by reducing the sputum culture conversion times for patients with RMP-resistant TB.

Topics: Adult; Antitubercular Agents; Female; Humans; Male; Middle Aged; Molecular Diagnostic Techniques; Predictive Value of Tests; Retrospective Studies; Rifampin; Sensitivity and Specificity; Sputum; Time Factors; Treatment Outcome; Tuberculosis, Multidrug-Resistant

Rifampin (RMP) resistant Mycobacterium tuberculosis is usually assumed to be resistant to all rifamycins. Increasing evidence indicates, however, that some rpoB mutations, detectable by rapid molecular diagnostics, confer resistance to RMP but not to rifabutin (RBT), suggesting that RBT may be effective for the treatment of M. tuberculosis with these mutations.. To determine if specific rpoB mutations reliably predict differential phenotypic resistance to RMP and RBT.. We selected 60 clinical M. tuberculosis isolates from a repository of multinational multidrug-resistant tuberculosis isolates and stratified them into two groups: 1) those with rpoB mutations suspected to confer differential resistance to RMP and RBT, and 2) those expected to be cross-resistant to RMP and RBT. These assumptions were tested by comparing the phenotypic susceptibilities of RMP/RBT with those predicted by mutations in the rpoB gene.. Of 20 suspected RMP-resistant/RBT-susceptible isolates, 15 were RMP-resistant but RBT-susceptible, 3 were RMP- and RBT-susceptible, and 2 were cross-resistant to both RMP and RBT. In comparison, 40 of 40 suspected cross-resistant isolates were both RMP- and RBT-resistant.. Our data support the association between specific rpoB mutations and differential resistance of M. tuberculosis to RMP and RBT. Clinical studies are required to investigate the efficacy of RBT in the treatment of M. tuberculosis harboring these mutations.

Topics: Antibiotics, Antitubercular; Bacterial Proteins; DNA-Directed RNA Polymerases; Drug Resistance, Multiple, Bacterial; Humans; Mutation; Mycobacterium tuberculosis; Retrospective Studies; Rifabutin; Rifampin; Tuberculosis, Multidrug-Resistant

India accounts for one-fifth of the global TB incidence. While the exact burden of childhood TB is not known, TB remains one of the leading causes of childhood mortality in India. Bacteriological confirmation of TB in children is challenging due to difficulty in obtaining quality specimens, in the absence of which diagnosis is largely based on clinical judgement. While testing multiple specimens can potentially contribute to higher proportion of laboratory confirmed paediatric TB cases, lack of high sensitivity tests adds to the diagnostic challenge. We describe here our experiences in piloting upfront Xpert MTB/RIF testing, for diagnosis of TB in paediatric population in respiratory and extra pulmonary specimens, as recently recommended by WHO.. Xpert MTB/RIF testing was offered to all paediatric (0-14 years) presumptive TB cases (both pulmonary and extra-pulmonary) seeking care at public and private health facilities in the project areas covering 4 cities of India.. Under this pilot project, 8,370 paediatric presumptive TB & presumptive DR-TB cases were tested between April and-November 2014. Overall, 9,149 specimens were tested, of which 4,445 (48.6%) were non-sputum specimens. Xpert MTB/RIF gave 9,083 (99.2%, CI 99.0-99.4) valid results. Of the 8,143 presumptive TB cases enrolled, 517 (6.3%, CI 5.8-6.9) were bacteriologically confirmed. TB detection rates were two fold higher with Xpert MTB/RIF as compared to smear microscopy. Further, a total of 60 rifampicin resistant TB cases were detected, of which 38 were detected among 512 presumptive TB cases while 22 were detected amongst 227 presumptive DR-TB cases tested under the project.. Xpert MTB/RIF with advantages of quick turnaround testing-time, high proportion of interpretable results and feasibility of rapid rollout, substantially improved the diagnosis of bacteriologically confirmed TB in children, while simultaneously detecting rifampicin resistance.

Topics: Adolescent; Antibiotics, Antitubercular; Body Fluids; Child; Child, Preschool; Female; Humans; Infant; Male; Mass Screening; Molecular Diagnostic Techniques; Mycobacterium tuberculosis; National Health Programs; Polymerase Chain Reaction; Reagent Kits, Diagnostic; Rifampin; Sensitivity and Specificity; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Topics: Adolescent; Adult; Antitubercular Agents; Burkina Faso; Female; Humans; Isoniazid; Male; Middle Aged; Mycobacterium tuberculosis; Real-Time Polymerase Chain Reaction; Rifampin; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Young Adult

Pulmonary tuberculosis still remains a major communicable disease worldwide. In 2013, 9 million people developed TB and 1.5 million people died from the disease. India constitutes 24% of the total TB burden. Early detection of TB cases is the key to successful treatment and reduction of disease transmission. Xpert MTB/RIF, an automated cartridge-based molecular technique detects Mycobacterium tuberculosis and rifampicin resistance within two hours has been endorsed by WHO for rapid diagnosis of TB. Our study is the first study from India with a large sample size to evaluate the performance of Xpert MTB/RIF assay in PTB samples. The test showed an overall sensitivity and specificity of 95.7% (430/449) and 99.3% (984/990) respectively. In smear negative-culture positive cases, the test had a sensitivity of 77.7%. The sensitivity and specificity for detecting rifampicin resistance was 94.5% and 97.7% respectively with respect to culture as reference standard. However, after resolving the discrepant samples with gene sequencing, the sensitivity and specificity rose to 99.0% and 99.3% respectively. Hence, while solid culture still forms the foundation of TB diagnosis, Xpert MTB/RIF proposes to be a strong first line diagnostic tool for pulmonary TB cases.

Topics: Adolescent; Adult; Antitubercular Agents; Bacterial Proteins; Biological Assay; DNA-Directed RNA Polymerases; Drug Resistance, Bacterial; Female; Humans; Male; Microscopy; Middle Aged; Molecular Diagnostic Techniques; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Sequence Analysis, DNA; Sputum; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary

Despite increasing reports of the linkage between diabetes and tuberculosis (TB), there is limited information regarding diabetes and TB drug resistance.. In this cross-sectional study, sputum and blood samples were collected from 304 adult patients in rural Andhra Pradesh. Rifampin resistance was assessed by Xpert MTB/RIF (Xpert), and diabetes status was based on self-report. Additionally, samples were assayed by acid-fast bacilli sputum smear microscopy (AFB) and QuantiFERON-TB Gold In-Tube (QFT-G), in order to compare relative diagnostic performances.. Among patients with confirmed TB (n = 194), diabetes was associated with 3.0-fold higher risk of rifampin resistance (95 % CI 1.3-6.7). Considering Xpert MTB/RIF the gold standard, AFB had lower sensitivity (72.2 vs. 82.5 %) and higher specificity (96.4 vs. 37.0 %) compared to QFT-G for diagnosing TB.. The increased risk of rifampin resistance in patients with diabetes highlights the need for integrated diabetes surveillance in TB programs, particularly in settings undergoing the epidemiological transition.

Topics: Adult; Cross-Sectional Studies; Diabetes Mellitus; Female; Humans; India; Male; Mycobacterium tuberculosis; Rifampin; Rural Population; Sensitivity and Specificity; Sputum; Tuberculosis; Tuberculosis, Multidrug-Resistant