colistin and Cross-Infection

Over the last decades, there has been a dramatic global increase in multidrug-resistant (MDR) pathogens particularly among Gram-negative bacteria (GNB).

Topics: Africa, Northern; Anti-Bacterial Agents; Antimicrobial Stewardship; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Genome, Bacterial; Microbial Sensitivity Tests; Middle East; Prevalence; Pseudomonas aeruginosa; Pseudomonas Infections

Several recent cases associating cleaned and high-level disinfected duodenoscopes with outbreaks of carbapenem-resistant Enterobacteriaceae (CRE) and related multidrug-resistant organisms (MDROs) may cause bronchoscopists, pulmonologists, and other stakeholders to inquire about the effectiveness of today's practices for reprocessing flexible bronchoscopes. The primary objectives of this study were to address this question and investigate the risk of bronchoscopes transmitting infections of CRE and related MDROs. The published literature and the US Food and Drug Administration's medical device database of adverse events were searched beginning in 2012, when endoscopy first emerged as a recognized risk factor for transmission of CRE. The Internet was also searched during this same time frame to identify other relevant cases. Several cases associating reprocessed bronchoscopes with infections of CRE or a related MDRO were identified. This study's findings suggest that bronchoscopes may pose an underrecognized potential for transmission of CRE and related MDROs, warranting greater public awareness, enhanced preventive measures, and updated reprocessing guidance. This study's data also suggest that the cleaning and high-level disinfection of bronchoscopes performed in accordance with published guidelines and manufacturer instructions may not always be sufficiently effective to eliminate this risk. Several factors were identified that can adversely affect a bronchoscope's reprocessing and pose a risk of transmission of these multidrug-resistant bacteria, including use of a damaged or inadequately serviced bronchoscope, and formation of an inaccessible biofilm. Recommendations are provided to improve the safety of flexible bronchoscopes, including supplementing their reprocessing with an enhanced measure such as sterilization when warranted, and strict adherence to a periodic servicing and maintenance schedule consistent with the bronchoscope manufacturer's instructions.

Topics: Anti-Bacterial Agents; beta-Lactam Resistance; Bronchoscopes; Bronchoscopy; Carbapenem-Resistant Enterobacteriaceae; Colistin; Cross Infection; Disinfection; Drug Resistance, Multiple, Bacterial; Enterobacteriaceae Infections; Equipment Contamination; Equipment Reuse; Humans; Klebsiella Infections; Klebsiella pneumoniae; Pseudomonas aeruginosa; Pseudomonas Infections

To determine the cost-effectiveness of selective digestive decontamination (SDD) as compared to selective oropharyngeal decontamination (SOD) in intensive care units (ICUs) with low levels of antimicrobial resistance.. Post-hoc analysis of a previously performed individual patient data meta-analysis of two cluster-randomised cross-over trials.. 24 ICUs in the Netherlands.. 12 952 ICU patients who were treated with ≥1 dose of SDD (n=6720) or SOD (n=6232).. SDD versus SOD.. The incremental cost-effectiveness ratio (ICER; ie, costs to prevent one in-hospital death) was calculated by comparing differences in direct healthcare costs and in-hospital mortality of patients treated with SDD versus SOD. A willingness-to-pay curve was plotted to reflect the probability of cost-effectiveness of SDD for a range of different values of maximum costs per prevented in-hospital death.. The ICER resulting from the fixed-effect meta-analysis, adjusted for clustering and differences in baseline characteristics, showed that SDD significantly reduced in-hospital mortality (adjusted absolute risk reduction 0.0195, 95% CI 0.0050 to 0.0338) with no difference in costs (adjusted cost difference €62 in favour of SDD, 95% CI -€1079 to €935). Thus, SDD yielded significantly lower in-hospital mortality and comparable costs as compared with SOD. At a willingness-to-pay value of €33 633 per one prevented in-hospital death, SDD had a probability of 90.0% to be cost-effective as compared with SOD.. In Dutch ICUs, SDD has a very high probability of cost-effectiveness as compared to SOD. These data support the implementation of SDD in settings with low levels of antimicrobial resistance.

Topics: Administration, Topical; Aged; Amphotericin B; Anti-Bacterial Agents; Antifungal Agents; Carrier State; Cephalosporins; Colistin; Cost-Benefit Analysis; Cross Infection; Decontamination; Drug Resistance, Microbial; Female; Gastrointestinal Tract; Health Care Costs; Hospital Mortality; Humans; Intensive Care Units; Length of Stay; Male; Middle Aged; Netherlands; Oropharynx; Randomized Controlled Trials as Topic; Tobramycin

Acinetobacter baumannii is an important opportunistic pathogen due to its capabilities for developing mechanisms of resistance to a wide range of antimicrobial agents including carbapenems. This review described the risk factors, antimicrobial susceptibility and mechanisms of carbapenem resistance of A. baumannii from different geographical regions of Saudi Arabia. Several factors including complexity of intensive care unit (ICU) environments, increased numbers of patients with serious diseases, wide spread gastrointestinal colonization and extensive use of antimicrobial drugs led to a wide prevalence of A. baumannii infections in hospitals in Saudi Arabia. A. baumannii has been noted to be less susceptible to antimicrobials agents, including carbapenems, over time, resulting in the evolution of multidrug-resistant (MDR) strains. Dissemination of MDR A. baumannii is attributed to the extreme use of wide-spectrum antimicrobial drugs in hospitals, cross infection between inpatients, invasive ICU procedures, and hospitalized patients with diabetic and cancer those are under frequent invasive diagnostic and therapeutic interventions. Although an increasing prevalence of colistin and tigecycline resistance has been reported in many hospitals, combinations of these agents with carbapenems or other antibiotics remain the best therapeutic choice and reasonably safe to treat patients with MDR A. baumannii infections. The wide distribution of carbapenem resistant A. baumannii (CRAB) due to several mechanisms with diverse genetic determinants has been documented. Although OXA-23 β-lactamase and OXA-51 β-lactamase are the most common genes responsible for CRAB, other novel genes such as blaVIM, PER-1-like and GES-5 have been discovered in carbapenem resistant strains. The high rates of MDR A. baumannii in Saudi hospitals indicate that extensive investigation into the molecular basis of MDR and developing new therapies of CRAB is needed. Moreover, the development of a local antibiogram database coupled with a nationwide antimicrobial stewardship and infection prevention program might help to improve our knowledge of the resistance patterns of A. baumannii, and in developing a treatment protocol for decreasing the infection burden in Saudi Arabia.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; beta-Lactam Resistance; beta-Lactamases; Carbapenems; Colistin; Cross Infection; Drug Resistance, Bacterial; Hospitals; Humans; Microbial Sensitivity Tests; Prevalence; Risk Factors; Saudi Arabia

Treatment of Acinetobacter baumannii has become a medical challenge because of the increasing incidence of multiresistant strains and a lack of viable treatment alternatives. This systematic review attempts to investigate the changes in resistance of A. baumannii to different classes of antibiotics in Iran, with emphasis on the antimicrobial activity of polymyxin B (PMB) and colistin (COL). Biomedical databases were searched for English-published articles evaluating microbiological activity of various antimicrobial agents, including PMB and COL. Then, the available data were extracted and analyzed. Thirty-one studies, published from 2009 to 2015, were identified which contain data for 3,018 A. baumannii clinical isolates. With the exception of polymyxins and tigecycline (TIG), there was a high rate of resistance to various groups of antibiotics, including carbapenems. The minimum inhibitory concentration (MIC) ranges for PMB and COL on A. baumannii isolates tested were 0.12-64 μg/ml and 0.001-128 μg/ml, respectively. Polymyxins showed adequate activity with no significant trends in the resistance rate during most of the study period. The incidence of resistance to TIG was estimated low from 2% to 38.4% among the majority of A. baumannii. The present systematic review of the published literatures revealed that multidrug-resistant (including carbapenem-resistant) strains of A. baumannii have increased in Iran. In these circumstances, the older antibiotics, such as COL or PMB, preferably in combination with other antimicrobials (rifampicin, meropenem), could be considered as the therapeutic solution against the healthcare-associated infections. Designing rational dosage regimens for patients to maximize the antimicrobial activity and minimize the emergence and prevalence of resistance is recommended.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; Carbapenems; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Humans; Iran; Meropenem; Microbial Sensitivity Tests; Minocycline; Polymyxin B; Rifampin; Thienamycins; Tigecycline

The wide dissemination of carbapenemase producing K. pneumoniae (KPC-Kp) has caused a public health crisis of global dimensions, due to the serious infections in hospitalized patients associated with high mortality. In 2014, we aim to review clinical data on KPC-Kp at a time when a pro-active strategy (combating the problem before it is established) is no longer useful, focusing on epidemiology, patient risk profile, infection control, digestive tract colonization and treatment issues such as the role of carbapenems or carbapenem sparing strategies, colistin and resistance, dual carbapenem administration and the role of tigecycline. All these issues are illustrated prospectively to provide a forum for a Consensus strategy when not only intensive care units but also medical and surgical wards are affected by the epidemics.

Topics: Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; Carbapenems; Colistin; Cross Infection; Drug Therapy, Computer-Assisted; Humans; Infection Control; Klebsiella Infections; Klebsiella pneumoniae; Minocycline; Risk Factors; Tigecycline

Infections caused by multi-drug-resistant Gram-negative bacteria, particularly Acinetobacter baumannii, Pseudomonas aeruginosa and Klebsiella pneumoniae, that cause nosocomial infections, represent a growing problem worldwide. The rapid increase in the prevalence of Gram-negative pathogens that are resistant to fluoroquinolones and aminoglycosides as well as all β-lactams, including carbapenems, monobactam, cephalosporins and broad-spectrum penicillins, has prompted the reconsideration of colistin as a valid therapeutic option. Colistin is an old class of cationic, which act by disrupting the bacterial membranes resulting in cellular death. Although there has been a significant recent increase in the data gathered on colistin, focusing on its chemistry, antibacterial activity, mechanism of action and resistance, pharmacokinetics, pharmacodynamics and new clinical application, the prevalence of colistin resistance has been very little reported in the literature. This review concentrates on recent literature aimed at optimizing the clinical use of this important antibiotic.. The available evidence from various studies (microbiological and clinical studies, retrieved from the PubMed, and Scopus databases) regarding the mechanisms and prevalence of resistance was evaluated.. Increasing use of colistin for treatment of infections caused by these bacteria has led to the emergence of colistin resistance in several countries worldwide. Although resistance to polymyxins is generally less than 10%, it is higher in the Mediterranean and South-East Asia (Korea and Singapore), where colistin resistance rates are continually increasing.. There is a critical need for effective infection prevention and control measures and strict use of antibiotics in the world to control the rise and spread of colistin resistance.

Topics: Anti-Bacterial Agents; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Gram-Negative Bacteria; Gram-Negative Bacterial Infections; Humans; Polymyxins; Prevalence

Klebsiella pneumoniae producing KPC-type carbapenemase causes severe nosocomial infection at a high mortality rate. Nosocomial pneumonia in particular is associated with high mortality, likely due to the unfavorable pulmonary pharmacokinetics of the antibiotics used against this agent. Therefore, early and accurate microbiological identification and susceptibility evaluation are crucial in order to optimize antibiotic therapy. We report a case of ventilator-associated pneumonia caused by colistin-resistant K. pneumoniae producing KPC-type carbapenemase treated using a carbapenem-sparing therapy and tailored according to the serum procalcitonin concentration in order to limit the duration of antibiotic therapy.

Topics: Adult; Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; Calcitonin; Calcitonin Gene-Related Peptide; Colistin; Cross Infection; Drug Resistance, Bacterial; Drug Therapy, Combination; Equipment Contamination; Fosfomycin; Humans; Klebsiella Infections; Klebsiella pneumoniae; Male; Minocycline; Pneumonia, Bacterial; Protein Precursors; Tigecycline; Treatment Outcome; Ventilators, Mechanical

The global spread of multi-drug resistant organisms (MDRO) is a major threat to public health. Fighting MDRO spread requires a multi-faceted approach as summarized in the German Antibiotic Resistance Strategy (DART). In the hospital, this includes antibiotic stewardship concepts and strict infection control measures. Treatment of MDRO is sophisticated. Within the last years, several antibiotics with activity against MRSA were launched and facilitate an individual therapy according to site of infection and co-morbidities. In contrast, novel antibiotics against carbapenemase producing Gram-negatives are still lacking. Current studies have shown, that a colistin-based combination treatment can improve the prognosis in these patients. The following article reviews MDRO definitions, burden of disease, treatment options and general strategies against MDRO.

Topics: Anti-Bacterial Agents; Bacterial Infections; Colistin; Cost of Illness; Cross Infection; Drug Resistance, Multiple, Bacterial; Drug Therapy, Combination; Gram-Negative Bacterial Infections; Humans; Methicillin-Resistant Staphylococcus aureus; Staphylococcal Infections

We report three cases of external ventricular derivation infections caused by multidrug-resistant Gram-negative rods and treated successfully with intraventricular colistin. The intrathecal or intraventricular use of colistin have been reported in more than 100 cases without any consensus on dosage, duration and type (monotherapy or combination therapy) of treatment. Based on our comprehensive review of the relevant literature relating to both clinical and pharmacokinetic data, we conclude that the intrathecal/intraventricular administration of colistin is a safe and effective option to treat central nervous system infections caused by multidrug-resistant Gram-negative bacteria.

Topics: Adolescent; Adult; Anti-Bacterial Agents; Central Nervous System Bacterial Infections; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Gram-Negative Aerobic Rods and Cocci; Gram-Negative Bacterial Infections; Humans; Injections, Intraventricular; Injections, Spinal; Male

Increasing use of colistin for multidrug-resistant Gram-negative bacterial infections has led to the emergence of colistin resistance in Klebsiella pneumoniae in several countries worldwide, including Europe (especially Greece), and colistin resistance rates are continually increasing. Heteroresistance rates, which were significantly higher than resistance rates, were found to be important. Although the mechanism underlying resistance is unclear, it has been suggested that it is related to lipopolysaccharide modification via diverse routes. Several factors have been reported as being associated with colistin resistance, with improper use and patient-to-patient transmission being most often cited. Total infections and infection-related mortality from colistin-resistant K. pneumoniae are high, but currently there are no established treatment regimens. However, several combination regimens that are mainly colistin-based have been found to be successful for treating such infections.

Topics: Anti-Bacterial Agents; beta-Lactamases; Colistin; Cross Infection; Drug Administration Schedule; Drug Resistance, Multiple, Bacterial; Drug Therapy, Combination; Humans; Klebsiella Infections; Klebsiella pneumoniae; Lipopolysaccharides; Microbial Sensitivity Tests; Treatment Outcome

Despite having a reputation of low virulence, Acinetobacter baumannii is an emerging multidrug-resistant (MDR) pathogen responsible for community- and hospital-acquired infections that are difficult to control and treat. Interest in this pathogen emerged about one decade ago because of its natural MDR phenotype, its capability of acquiring new mechanisms of resistance and the existence of nosocomial outbreaks. Recent advances in molecular biology, including full genome sequencing of several A. baumannii isolates, has led to the discovery of the extraordinary plasticity of their genomes, which is linked to their great propensity to adapt to any environment, including hospitals. In this context, as well as the increasing antimicrobial resistance amongst A. baumannii isolates to the last-line antibiotics carbapenems and colistin, therapeutic options are very limited or absent in some cases of infections with pandrug-resistant bacteria. However, a large proportion of patients may be colonised by such MDR bacteria without any sign of infection, leading to a recurrent question for clinicians as to whether antibiotic treatment should be given and will be effective in the presence of resistance mechanisms. The worldwide emergence of A. baumannii strains resistant to colistin is worrying and the increasing use of colistin to treat infections caused by MDR bacteria will inevitably increase the recovery rate of colistin-resistant isolates in the future. Current knowledge about A. baumannii, including biological and epidemiological aspects as well as resistance to antibiotics and antibiotic therapy, are reviewed in this article, in addition to therapeutic recommendations.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; Carbapenems; Carrier State; Colistin; Community-Acquired Infections; Cross Infection; Drug Resistance, Multiple, Bacterial; Europe; Gene Transfer, Horizontal; Humans

Topics: Anti-Bacterial Agents; Bacterial Infections; beta-Lactams; Biological Availability; Cephalosporins; Colistin; Cross Infection; Dose-Response Relationship, Drug; Drug Resistance, Multiple, Bacterial; Drug Therapy, Combination; Fluoroquinolones; Half-Life; Humans; Infusions, Intravenous; Microbial Sensitivity Tests; Practice Patterns, Physicians'

Lower respiratory tract infections, due to Pseudomonas aeruginosa or Acinetobacter baumannii, are frequently encountered in patients with cystic fibrosis (CF) or in patients developing nosocomial pneumonias. Both of these conditions bear a high mortality risk and aggressive antibiotic therapy is necessary. Inhaled antibiotics might represent an effective therapeutic approach for these diseases as it has demonstrated good bactericidal efficacy and safety in both preclinical and clinical studies. This colistin formulation might be useful particularly in patients with respiratory tract infections due to multidrug-resistant Gram-negative bacteria. Its main advantages are a better safety profile with a minimal or absent risk of nephrotoxicity.. This paper discusses the available systemic formulations of colistin, with pharmacokinetic and safety profiles, followed by an overview of inhaled antibiotics in lower respiratory tract infections.. Inhaled colistin should be used selectively as monotherapy in chronic infections with P. aeruginosa in CF patients, whereas in patients with hospital/ventilator-acquired pneumonia (HAP/VAP), it should be used in a combined regimen with systemic antibiotics.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Administration, Inhalation; Animals; Anti-Bacterial Agents; Bronchiectasis; Colistin; Cross Infection; Cystic Fibrosis; Drug Synergism; Drug Therapy, Combination; Humans; Pneumonia, Ventilator-Associated; Pseudomonas aeruginosa; Pseudomonas Infections; Respiratory Tract Infections

Although colistin has recently played a key role in the treatment of nosocomial infections due to multidrug resistant Gram-negative pathogens, there is a lack of clinical studies examining colistin pharmacokinetics (PKs) in humans. This refers to all routes of colistin administration in clinical practice. Colistin PK data are also limited in critically ill patients.. Literature search took into account data dealing with colistin PK obtained from animal studies performed during previous decades (1970s, 1980s and 1990s) and from recent human studies performed during the last decade.. Valuable information on pharmacodynamics (PD)/PK of colistin used in the treatments of nosocomial infections due to multidrug resistant Gram-negative pathogens, mostly Pseudomonas aeruginosa, Acinetobacter baumannii and Klebsiella pneumoniae. A better understanding of PKs could offer significant improvement of colistin use in humans, especially optimization of colistin doses in different routes of administration in order to maximize clinical efficacy and minimize adverse effects and rate of resistance.. There is a lack of human studies on colistin PK and PD. Significant PD parameters best predicting colistin efficacy and their optimal values such as C(max):MIC ratio, AUC/MIC and T > MIC have not yet been clearly defined. It should be noted that further investigation on colistin PK/PD in vitro and in vivo models is required.

Topics: Animals; Anti-Bacterial Agents; Area Under Curve; Clinical Trials as Topic; Colistin; Critical Illness; Cross Infection; Drug Evaluation, Preclinical; Drug Resistance, Multiple, Bacterial; Gram-Negative Bacteria; Gram-Negative Bacterial Infections; Humans; Microbial Sensitivity Tests

Acinetobacter baumannii is an opportunistic Gram-negative pathogen with increasing relevance in a variety of hospital-acquired infections especially among intensive care unit patients. Resistance to antimicrobial agents is the main reason for A. baumannii spread. A. baumannii outbreaks described worldwide are caused by a limited number of genotypic clusters of multidrug-resistant strains that successfully spread among hospitals of different cities and countries. In this article, we will focus on the mechanisms responsible for resistance to antimicrobials and disinfectants in A. baumannii and the epidemiology of drug-resistant A. baumannii in healthcare facilities. We will also discuss the therapeutic and infection control strategies for management of drug-resistant A. baumannii epidemics.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; Colistin; Cross Infection; DNA Fingerprinting; DNA, Ribosomal Spacer; Drug Resistance, Multiple, Bacterial; Humans; Infection Control; Molecular Epidemiology; RNA, Ribosomal, 16S; Sulbactam

Hospital-acquired pneumonia is a common complication that continues to have a poor cure rate in some patients with intravenous therapy alone. Aerosolized antibiotics are theoretically attractive in an attempt to optimize lung concentrations of antibiotics. Limited data suggest that aerosolized aminoglycosides or colistin in addition to intravenous therapy results in good response rates in patients with multidrug-resistant organisms or nonresponding pneumonia. Adverse events can occur, especially with colistin. When used, care should be taken to properly compound and administer aerosolized antibiotics to ensure tolerability and good drug delivery.

Topics: Administration, Inhalation; Aerosols; Aminoglycosides; Anti-Bacterial Agents; Colistin; Cross Infection; Drug Administration Schedule; Drug Dosage Calculations; Drug Resistance, Multiple, Bacterial; Humans; Intensive Care Units; Lung; Nebulizers and Vaporizers; Pneumonia, Ventilator-Associated; Pseudomonas aeruginosa; Randomized Controlled Trials as Topic; Retrospective Studies; Treatment Outcome

Treatment limitations exist for drug-resistant Acinetobacter baumannii central nervous system (CNS) infection. We conducted a retrospective study and systematic literature review to identify patients with drug-resistant A. baumannii CNS infection who received primary or adjunct intrathecal or intraventricular (IT/IVT) colistin. In a case series of seven Thai patients and 17 patients identified in the literature, clinical and microbiological cure rates with IT/IVT colistin therapy were 83% and 92%, respectively. Three patients (13%) developed chemical ventriculitis and one (4%) experienced treatment-associated seizures. Death was associated with delayed IT/IVT colistin therapy compared to survival (mean time from diagnosis to IT/IVT colistin, 7 vs. 2 days; p 0.01). The only independent predictor of mortality was the severity of illness (APACHE II score > 19, adjusted odds ratio 49.5; 95% CI 1.7-1428.6; p 0.02). This case series suggests that administration of primary or adjunctive IT/IVT colistin therapy was effective for drug-resistant A. baumannii CNS infection.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Adolescent; Adult; Aged; Anti-Bacterial Agents; APACHE; Central Nervous System Bacterial Infections; Central Nervous System Infections; Child; Child, Preschool; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Female; Humans; Injections, Intraventricular; Injections, Spinal; Male; Middle Aged; Risk Factors; Thailand; Treatment Outcome

The administration of antibiotics by the inhaled route is a widely recognized treatment in patients with cystic fibrosis (CF) and bronchiectasis. Tobramycin solution for inhalation (TOBI) has been available for many years and is licensed in the USA and Europe. While strong data support the use of aerosolized antibiotics for the treatment of respiratory infections in patients with CF or bronchiectasis, only a few clinical studies have examined the role of aerosolized antibiotics in the treatment of pneumonia, including ventilator-associated pneumonia (VAP) in these patients. During the last decade increasing interest has been directed towards alternative treatments to the systemic administration of antimicrobial agents for the treatment of patients with hospital-acquired pneumonia or VAP due to multidrug-resistant (MDR) Gram-negative bacteria. Recent publications demonstrate the clinical benefits from administering inhaled aminoglycosides or polymyxins in patients with hospital-acquired pneumonia or VAP. In addition to antibiotics, antifungals, and antivirals have been administered by inhalation to specific groups of critically ill patients. However, randomized controlled trials dealing with the administration of anti-infective agents via the respiratory tract are necessary in order to validate the efficacy, safety, advantages, and disadvantages of this therapeutic approach for the treatment of nosocomial pneumonia.

Topics: Administration, Inhalation; Aerosols; Anti-Bacterial Agents; Colistin; Cross Infection; Humans; Pneumonia, Bacterial; Pneumonia, Ventilator-Associated; Randomized Controlled Trials as Topic

Pseudomonas aeruginosa is a major hospital-associated pathogen that can cause severe infections, most notably in patients with cystic fibrosis or those hospitalized in intensive care units. In this context, the current increase in incidence of multi-drug resistant (MDR) isolates of P. aeruginosa (MDRPA) raises serious concerns. MDR in P. aeruginosa is defined as the resistance to 3 or 4 of the following antibiotic classes: penicillins/cephalosporins/monobactams, carbapenems, aminoglycosides, and fluoroquinolones. These strains constantly cumulate several resistance mechanisms as a consequence of multiple genetic events, i.e., chromosomal mutations or horizontal transfers of resistance genes. Involved mechanisms may include active efflux, impermeability resulting from porins loss, plasmid-encoded b-lactamases/carbapenemases or aminoglycosides-modifying enzymes, and enzymatic or mutation-associated changes in antibiotics targets. Antibiotic selection pressure represents the leading risk factor for MDRPA acquisition. Colistin (polymyxin E) remains active on virtually all MDRPA isolates, and increasingly appears as the last available option to treat infections caused by these strains. However, the emergence of colistin resistance has been reported in P. aeruginosa, which may announce the spread of pan-resistant strains in a close future.

Topics: Anti-Bacterial Agents; Ciprofloxacin; Colistin; Cross Infection; Drug Resistance, Multiple; Humans; Pseudomonas aeruginosa; Pseudomonas Infections

Acinetobacter baumannii is an important cause of nosocomial infections, mainly in patients in intensive care units. This microorganism, although with slight differences depending on the country, presents resistance to multiple antimicrobial agents, occasionally including resistance to colistin: hence, it can be considered the paradigm of nosocomial multiresistant bacteria. This review analyzes the evolution of antimicrobial resistance and the molecular bases associated with the increase in antimicrobial resistance, as well as the current treatment of Acinetobacter infections. Although controversy remains, the pooled data suggest that infections by A. baumannii may be associated with considerable attributable mortality. Moreover, in cases of pneumonia and bacteraemia, inappropriate treatment is associated with, among other factors, mortality. Therefore, treatment should be carefully considered.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Drug Therapy, Combination; Humans; Minocycline; Patient Selection; Rifampin; Sulbactam; Tigecycline; Treatment Outcome

Based on the worldwide prevalence of multidrug-resistant strains of Pseudomas aeruginosa and the fact that no newer antipseudomonal agents are available, this article aims to investigate therapeutic solutions for combating infections caused by P aeruginosa, including multidrug-resistant strains. The article focuses mainly on colistin, the re-emerging old antibiotic that possesses prominent antipseudomonal activity in vitro and on doripenem, a newer carbapenem that seems to be close to its global marketing. Regarding older antipseudomonal antibiotics that have been reviewed extensively, only newer aspects on their use are considered in this article.

Topics: Anti-Bacterial Agents; Carbapenems; Colistin; Cross Infection; Doripenem; Drug Resistance, Multiple, Bacterial; Humans; Microbial Sensitivity Tests; Pseudomonas aeruginosa; Pseudomonas Infections; Randomized Controlled Trials as Topic

Hospital-acquired infections due to multidrug-resistant gram-negative bacteria constitute major health problems, since the medical community is continuously running out of available effective antibiotics and no new agents are in the pipeline. Polymyxins, a group of antibacterials that were discovered during the late 1940s, represent some of the last treatment options for these infections. Only two polymyxins are available commercially, polymyxin E (colistin) and polymyxin B. Although several reviews have been published recently regarding colistin, no review has focused on the similarities and differences between polymyxin B and colistin. These two medications have many similarities with respect to mechanism of action, antimicrobial spectrum, clinical uses and toxicity. However, they also differ in several aspects, including chemical structure, formulation, potency, dosage and pharmacokinetic properties.

Topics: Anti-Bacterial Agents; Bacteria; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Gram-Negative Bacterial Infections; Humans; Microbial Sensitivity Tests; Polymyxin B; Structure-Activity Relationship

The spectrum of available therapeutic options has become drastically narrowed in recent years, particularly for nosocomial multidrug-resistant gram-negative pathogens. This therapeutic void has created a resurgence of interest in colistin. In 5 published series since 1999, clinical response rates for pneumonia due to Pseudomonas aeruginosa or Acinetobacter baumannii treated with intravenous colistin have ranged from 25% to 62%, despite high severity of illness at baseline. De novo nephrotoxicity was observed in 8%-36% of patients, despite close attention to both appropriate dosing and duration of treatment. Neurotoxicity, which was commonly described in the old colistin era, has been exceedingly rare in recent experience. Aerosolized therapy as an adjunct to systemic treatment appears promising, but the current published data are much too limited to allow determination of the incremental benefit of the addition of aerosolized treatment to systemic treatment. Colistin is a reasonably safe last-line therapeutic alternative for pneumonia due to multi- or panresistant P. aeruginosa or A. baumannii.

Topics: Acinetobacter; Acinetobacter Infections; Administration, Inhalation; Anti-Bacterial Agents; Colistin; Cross Infection; Humans; Infusions, Parenteral; Pneumonia, Bacterial; Pseudomonas aeruginosa; Pseudomonas Infections; Retrospective Studies; Treatment Outcome; Ventilators, Mechanical

Nosocomial infections with organisms resistant to multiple antibiotic agents represent an evolving challenge in the intensive care setting, particularly in patients requiring surgical diversion of cerebrospinal fluid. The authors present the case of a 51-year-old woman who endured protracted hospitalization and required multiple surgeries including placement of a ventriculoperitoneal shunt. The shunt subsequently became colonized with Pseudomonas aeruginosa, which demonstrated intermediate sensitivity to amikacin and full resistance to all other antibiotics tested 'After failing to respond to intravenous imipenem as well as intravenous and intrathecal amikacin, the patient was successfully treated with intravenous and intrathecal colistin. Colistin is a polymyxin-type antibiotic, rarely used outside of topical application because of reported nephrotoxicity associated with parenteral administration. With activity limited to Gram-negative organisms, colistin is bactericidal by directly disrupting the structure of cell membranes. Authors of a few case reports in the literature have described successful treatment of various ventriculitis with the intrathecal administration of colistin. With bacterial resistances outpacing the pharmaceutical industry's ability to develop novel antibiotics, colistin represents an important alternative in situations involving multidrug-resistant organisms.

Topics: Anti-Bacterial Agents; Cerebral Ventricles; Cerebrospinal Fluid Shunts; Colistin; Cross Infection; Drug Resistance, Multiple; Encephalitis; Female; Humans; Injections, Spinal; Middle Aged; Postoperative Complications; Pseudomonas Infections

Pseudomonas aeruginosa is one of the leading gram-negative organisms associated with nosocomial infections. The increasing frequency of multi-drug-resistant Pseudomonas aeruginosa (MDRPA) strains is concerning as efficacious antimicrobial options are severely limited. By searching MEDLINE from January 1966-February 2005 and relevant journals for abstracts, we reviewed the frequency, risk factors, and patient outcomes of MDRPA nosocomial infections in critically ill patients, determined the available antimicrobial therapies, and then provided recommendations for clinicians. The definition of MDRPA was established as isolates intermediate or resistant to at least three drugs in the following classes: beta-lactams, carbapenems, aminoglycosides, and fluoroquinolones. Reported rates of MDRPA varied from 0.6-32% according to geographic location and type of surveillance study. Risk factors for MDRPA infection included prolonged hospitalization, exposure to antimicrobial therapy, and immunocompromised states such as human immunodeficiency virus infection. Emergence of MDRPA isolates during therapy was reported in 27-72% of patients with initially susceptible P. aeruginosa isolates. Patients with severe MDRPA infections should be treated with combination therapy, consisting of an antipseudomonal beta-lactam with an aminoglycoside or fluoroquinolone rather than aminoglycoside and fluoroquinolone combinations, to provide adequate therapy and improve patient outcomes. Synergy has been observed when resistant antipseudomonal drugs were combined in vitro against MDRPA with successful clinical application reported in two centers. Colistin with adjunctive therapy, such as a beta-lactam or rifampin, may be a useful agent in MDRPA when antimicrobial options are limited, but patients should be monitored closely for toxicities associated with this agent. Standardization of terminology for MDRPA isolates is needed for consistency and comparability of surveillance and institutional reports. Clinical studies are needed to identify risk factors for MDRPA development and to determine the economic impact of these infections, as well as to determine the most efficacious antimicrobial regimens and duration of therapy to maximize outcomes in the treatment of MDRPA infections.

Topics: Anti-Bacterial Agents; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Drug Therapy, Combination; Humans; Meropenem; Polymyxin B; Pseudomonas aeruginosa; Pseudomonas Infections; Thienamycins

To review and evaluate clinically relevant epidemiology, microbiology, and clinical studies regarding the treatment of multidrug-resistant Acinetobacter infections.. Pertinent literature was identified by a MEDLINE search (1966-September 2003) and through secondary bibliographies of pertinent articles.. All English-language articles identified from data sources were evaluated for clinical relevance.. Acinetobacter baumannii has emerged as a worldwide problem as a nosocomial pathogen in hospitalized patients. Acinetobacter spp. can cause a multitude of infections including pneumonia, bacteremia, meningitis, urinary tract infections, and skin and soft tissue infections, and the mortality associated with these infections is high. Isolates resistant to almost all commercially available antimicrobials have been identified, thus limiting treatment options. The development of new agents and reappraisal of older compounds (ie, polymyxins, ampicillin/sulbactam) are necessary as we consider the optimal treatment of these multidrug-resistant organisms.. There is no simple answer to the treatment of Acinetobacter infections. Eradication of Acinetobacter spp. requires adherence to good infection control practices and prudent antibiotic use, as well as effective antimicrobial therapy. Alternative therapies such as colistin, ampicillin/sulbactam, and tetracycline are potential options, but prospective, randomized, controlled trials are still lacking.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; Colistin; Cross Infection; Disease Outbreaks; Drug Resistance, Multiple, Bacterial; Humans; Randomized Controlled Trials as Topic; Risk Factors; Sulbactam; Tetracyclines

Selective decontamination of the digestive tract (SDD) is a strategy designed to prevent or minimize the impact of infections by potentially pathogenic micro-organisms in critically ill patients requiring long-term mechanical ventilation. SDD is a four-component protocol to control the three types of infections occurring in intensive care patients: (a) a parenteral antibiotic, cefotaxime, for a few days to prevent primary endogenous infections that generally occur 'early'; (b) the topical antimicrobial drugs colistine (polymyxin E), tobramycin and amphotericin B (together: PTA) used throughout the stay in the intensive care unit (ICU) to prevent secondary endogenous infections developing in general 'late'; (c) a high standard of hygiene to prevent exogenous infections that may occur throughout the ICU stay; (d) surveillance samples of throat and rectum to distinguish between the three types of infection, to monitor compliance and efficacy of treatment and to detect emergence of resistance at an early stage. The most recent and rigorous meta-analysis examined 33 randomized SDD trials involving 5727 patients. It shows significant reductions, in overall mortality by 20% and in the incidence of lower airway infections by 65%. It failed to detect any report on the emergence of resistance and associated superinfections and/or out-breaks in the 33 studies covering a period of more than 10 years. Using the criterion of cost-per-survivor, four recent randomised trials showed that it is cheaper to produce a survivor using SDD than with the traditional approach.

Topics: Amphotericin B; Bacterial Infections; Cefotaxime; Clinical Protocols; Colistin; Critical Care; Critical Illness; Cross Infection; Decontamination; Digestive System; Drug Therapy, Combination; Female; Humans; Intensive Care Units; Male; Survival Rate; Tobramycin

Topics: Animals; Antibodies, Bacterial; Antineoplastic Agents; Arthritis, Infectious; Bone Diseases; Burns; Carbenicillin; Carrier State; Colistin; Cross Infection; Cystic Fibrosis; Disease Models, Animal; Drug Therapy, Combination; Gentamicins; Humans; Immunologic Deficiency Syndromes; Leukemia; Lung Diseases; Pneumonia; Polymyxins; Pseudomonas aeruginosa; Pseudomonas Infections; Respiratory Therapy; Skin Diseases, Infectious; Surgical Wound Infection; Transplantation, Homologous

In vitro models showing synergism between polymyxins and carbapenems support combination treatment for carbapenem-resistant Gram-negative (CRGN) infections. We tested the association between the presence of in vitro synergism and clinical outcomes in patients treated with colistin plus meropenem.. This was a secondary analysis of AIDA, a randomized controlled trial comparing colistin with colistin-meropenem for severe CRGN infections. We tested in vitro synergism using a checkerboard assay. Based on the fractional inhibitory concentration (ΣFIC) index for each colistin-meropenem combination, we categorized results as synergistic, antagonistic or additive/indifferent. The primary outcome was clinical failure at 14 days. Secondary outcomes were 14- and 28-day mortality and microbiological failure.. The sample included 171 patients with infections caused by carbapenem-resistant Acinetobacter baumannii (n = 131), Enterobacteriaceae (n = 37) and Pseudomonas aeuruginosa (n = 3). In vitro testing showed synergism for 73 isolates, antagonism for 20 and additivism/indifference for 78. In patients who received any colistin plus meropenem, clinical failure at 14 days was 59/78 (75.6%) in the additivism/indifference group (reference category), 54/73 (74.0%) in the synergism group (adjusted odds ratio (aOR) 0.76, 95% CI 0.31-1.83), and 11/20 (55%) in the antagonism group (aOR 0.77, 95% CI 0.22-2.73). There was no significant difference between groups for any secondary outcome. Comparing the synergism group to patients treated with colistin monotherapy, synergism was not protective against 14-day clinical failure (aOR 0.52, 95% CI 0.26-1.04) or 14-day mortality (aOR1.09, 95% CI 0.60-1.96).. In vitro synergism between colistin and meropenem via checkerboard method did not translate into clinical benefit.

Topics: Aged; Aged, 80 and over; Carbapenems; Colistin; Cross Infection; Drug Resistance, Bacterial; Drug Synergism; Female; Gram-Negative Bacteria; Gram-Negative Bacterial Infections; Humans; Male; Meropenem; Microbial Sensitivity Tests; Middle Aged; Pneumonia, Bacterial; Treatment Outcome

Ninety-four patients infected with carbapenem-resistant Acinetobacter baumannii were randomized to receive colistin alone or colistin plus fosfomycin for 7 to 14 days. The patients who received combination therapy had a significantly more favorable microbiological response and a trend toward more favorable clinical outcomes and lower mortality than those who received colistin alone. (This study has been registered at ClinicalTrials.gov under registration no. NCT01297894.).

Topics: Acinetobacter baumannii; Acinetobacter Infections; Aged; Anti-Bacterial Agents; Carbapenems; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Drug Therapy, Combination; Female; Fosfomycin; Humans; Male; Microbial Sensitivity Tests; Pilot Projects; Treatment Outcome

Topics: Administration, Intravenous; Aged; Amphotericin B; Anti-Bacterial Agents; Cefotaxime; Cluster Analysis; Colistin; Critical Care; Cross Infection; Cross-Over Studies; Decontamination; Dose-Response Relationship, Drug; Drug Administration Schedule; Female; Gastrointestinal Tract; Hospital Mortality; Humans; Intensive Care Units; Intubation, Gastrointestinal; Male; Middle Aged; Netherlands; Odds Ratio; Oropharynx; Primary Prevention; Survival Analysis; Tobramycin; Treatment Outcome

Selective digestive decontamination (SDD) and selective oropharyngeal decontamination (SOD) are effective in improving survival in patients under intensive care. In this study possible differential effects in surgical and non-surgical patients were investigated.. This was a post hoc subgroup analysis of data from a cluster-randomized multicentre trial comparing three groups (SDD, SOD or standard care) to quantify effects among surgical and non-surgical patients. The primary study outcome was 28-day mortality rate. Duration of mechanical ventilation, duration of intensive care unit (ICU) and hospital length of stay, and bacteraemia rates were secondary outcomes.. The subgroup analyses included a total of 2762 surgical and 3165 non-surgical patients. Compared with standard care, adjusted odds ratios (ORs) for mortality were comparable in SDD-treated surgical and non-surgical patients: 0·86 (95 per cent confidence interval 0·69 to 1·09; P = 0·220) and 0·85 (0·70 to 1·03; P = 0·095) respectively. However, duration of mechanical ventilation, ICU stay and hospital stay were significantly reduced in surgical patients who had SDD. SOD did not reduce mortality compared with standard treatment in surgical patients (adjusted OR 0·97, 0·77 to 1·22; P = 0·801); in non-surgical patients it reduced mortality (adjusted OR 0·77, 0·63 to 0·94; P = 0·009) by 16·6 per cent, representing an absolute mortality reduction of 5·5 per cent with number needed to treat of 18.. Subgroup analysis found similar effects of SDD in reducing mortality in surgical and non-surgical ICU patients, whereas SOD reduced mortality only in non-surgical patients. The hypothesis-generating findings mandate investigation into mechanisms between different ICU populations.

Topics: Administration, Oral; Amphotericin B; Anti-Bacterial Agents; Antibiotic Prophylaxis; Bacteremia; Cefotaxime; Cluster Analysis; Colistin; Critical Care; Cross Infection; Decontamination; Digestive System Diseases; Drug Combinations; Female; Hospital Mortality; Humans; Infusions, Intravenous; Intubation, Gastrointestinal; Length of Stay; Male; Middle Aged; Oropharynx; Pharyngeal Diseases; Respiration, Artificial; Tobramycin

Cases of ventilator-associated pneumonia (VAP) due to multidrug-resistant (MDR) Acinetobacter baumannii and Pseudomonas aeruginosa are common in hospitalized patients at Siriraj Hospital, Bangkok, Thailand. Parenteral colistimethate sodium (CMS) has been used for therapy of VAP caused by MDR A. baumannii and P. aeruginosa at Siriraj Hospital over the past few years, with modest favourable outcomes. Objectives To determine whether nebulized CMS as adjunctive therapy of Gram-negative VAP was safe and beneficial.. This was a randomized controlled study in 100 adults who developed Gram-negative VAP (clinical trial registration number: NCT00920270). All patients received systemic antibiotics according to the decisions of their responsible physicians. The patients were randomized to receive an additional 4 mL of nebulized sterile normal saline (NSS) (n = 49) or nebulized CMS equivalent to 75 mg of colistin base in 4 mL of NSS (n = 51) every 12 h until systemic antibiotic therapy of VAP was ended.. The baseline characteristics of the patients and conventional therapy of VAP in both groups were comparable. Most of the cases of VAP were caused by MDR A. baumannii and/or P. aeruginosa. All isolates of Gram-negative bacteria were susceptible to colistin. Favourable clinical outcome was 51.0% in the CMS group and 53.1% in the control group (P = 0.84). Patients in the CMS group had significantly more favourable microbiological outcome when compared with patients in the control group (60.9% versus 38.2%, P = 0.03). Bronchospasm was observed in 7.8% of patients in the CMS group and in 2.0% of patients in the control group (P = 0.36). Renal impairment was observed in 25.5% of patients in the CMS group and in 22.4% of patients in the NSS group (P = 0.82).. Nebulized CMS as adjunctive therapy of Gram-negative VAP seems to be safe. However, a beneficial effect on clinical outcomes of adjunctive nebulized CMS for therapy of Gram-negative VAP was not ascertained.

Topics: Aged; Aged, 80 and over; Anti-Bacterial Agents; Colistin; Cross Infection; Female; Gram-Negative Bacteria; Gram-Negative Bacterial Infections; Humans; Male; Middle Aged; Nebulizers and Vaporizers; Pneumonia, Bacterial; Pneumonia, Ventilator-Associated; Treatment Outcome

The nosocomial spread of pan-antibiotic-resistant nonfermentative bacteria is an increasing concern. This study investigated the microbiologic and epidemiologic characteristics of a hospital outbreak due to alginate-producing, pan-antibiotic-resistant Pseudomonas aeruginosa (PAR-Pa).. All patients with infection with a P. aeruginosa strain that was resistant to all Clinic Laboratory Standards Institute-suggested antimicrobial agents between November 2004 and May 2005 were included in the study. Alginate production detection and pulsed-field gel electrophoresis (PFGE) typing were done for the patient and environmental surveillance isolates. A matched case-control study was performed to identify risk factors and evaluate outcomes.. PFGE analysis of a total of 35 PAR-Pa isolates (28 patient and 7 environmental surveillance isolates) identified a single epidemic clone as responsible for the outbreak. All epidemic isolates were alginate-producing and susceptible only to colistin. The Student t-test demonstrated that a longer stay in the intensive care unit (ICU) (6.64 days vs 1.83 days; P < .05) significantly increased the risk of PAR-Pa infection. Systemic PAR-Pa infection resulted in higher mortality (85.7% vs 27.8%; P < .05). Multivariate analysis determined that therapeutic failure (odds ratio = 24.7; 95% confidence interval = 4.144 to 147.221; P < .05) was the independent risk factor related to this high mortality. Localized PAR-Pa infections were associated with longer hospital stays (46.2% vs 14.4%; P < .05) and higher rates of surgery (85.7% vs 15.4%; P < .05) and amputation (42.8% vs 0%; P < .05). The recovery of the pathogen from staff hands and frequently handled surfaces suggests possible handborne transmission. Improved hygienic standards and application of strict contact precautions, including isolation, reduced the spread of the pathogen.. This study illustrates the ability of pan-antibiotic-resistant P. aeruginosa to cause an outbreak with significant mortality and stresses the need for precautions to prevent the spread of such highly resistant strains.

Topics: Alginates; Anti-Bacterial Agents; APACHE; Case-Control Studies; Colistin; Confidence Intervals; Cross Infection; Disease Outbreaks; Drug Resistance, Multiple, Bacterial; Electrophoresis, Gel, Pulsed-Field; Female; Hospital Bed Capacity, 500 and over; Hospitals, University; Humans; Infection Control; Intensive Care Units; Male; Middle Aged; Multivariate Analysis; Odds Ratio; Pseudomonas aeruginosa; Pseudomonas Infections; Retrospective Studies; Risk Factors; Turkey

The increased incidence of nosocomial infections by multi-drug resistant Acinetobacter baumannii creates demand on the application of some combinations of older antimicrobials on that species. We conducted the present observational study to evaluate the efficacy of intravenous and aerosolized colistin combined with rifampicin in the treatment of critically patients with nosocomial infections caused by multiresistant A. baumannii.. Critically ill patients with nosocomial infections caused by A. baumannii resistant to all antibiotics except colistin in a medical intensive care unit. Diagnosis of infection was based on clinical data and isolation of bacteria. The bacterial susceptibilities to colistin were tested. Clinical response to colistin+rifampicin was evaluated.. Twenty-six patients (43.58+/-18.29 years, Acute Physiology and Chronic Health Evaluation II Score (APACHE II): 6.35+/-2.99), of whom 16 cases of nosocomial pneumonia treated by aerosolized colistin (1x10(6) IU three times/day) associated with intravenous rifampicin (10 mg/kg every 12h), nine cases of bacteraemia treated by intravenous colistin (2x10(6)IU three times/day) associated with intravenous rifampicin (10 mg/kg every 12h) in which three cases associated with ventilator associated pneumonia and one case of nosocomial meningitis treated by intrathecal use of colistin associated with intravenous rifampicin. The clinical evolution was favourable for all ill patients. Concerning side effects, we have noticed a moderate hepatic cytolysis in three patients.. This is the first clinical report of colistin combined with rifampicin for treatment of A. baumannii infection. Despite the lack of a control group and the limited number of patients, the results seem to be encouraging.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Adult; Anti-Bacterial Agents; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Drug Therapy, Combination; Female; Humans; Male; Middle Aged; Rifampin; Treatment Outcome

The prevalence of Helicobacter pylori is increased in healthcare workers and in intensive care nurses. Exposure to H. pylori from gastric secretions and faeces are probably the main sources of transmission to healthcare workers. Routine use of selective decontamination of digestive tract (SDD) in an intensive care unit suppresses H. pylori in critically ill patients. It was questioned whether this suppression and the subsequent decreased exposure to H. pylori for intensive care nurses would lead to a lower prevalence of H. pylori infection. Helicobacter pylori infection prevalence in intensive care nurses from a unit routinely using SDD (group I) was compared to that of nurses from a unit not using SDD (group II). Heathcare workers from other departments of the hospital where no SDD was used (group III) served as a control group. Persons using proton pump inhibitors were excluded. Helicobacter pylori was detected by Laser Assisted Ratio Analyser(13)C-urea breath test (UBT) and serology. This could not be performed in three out of 64 in group I, five out of 55 in group II and five out of 55 in group III (total UBTs = 169). The prevalence of H. pylori infection was 11% (7/61) in group I and 25.5% (14/50) in group II (P= 0.027). In group III, the prevalence of H. pylori infection was 16% (8/45), which was not significantly different from both group I and II. Sero-prevalence in group I was 18.6%, 27% in group II (ns) and 24% in group III. Mean age in the three groups was 35.9, 37.8 and 36.6 years, respectively (ns). In conclusion, the prevalence of H. pylori infection among intensive care nurses is lower in nurses from a unit using SDD compared to a non SDD-using unit. Acquisition of H. pylori by transmission from critically ill patients appears to be diminished through SDD use.

Topics: Adult; Amphotericin B; Breath Tests; Colistin; Critical Care; Critical Illness; Cross Infection; Cross-Sectional Studies; Drug Therapy, Combination; Helicobacter Infections; Helicobacter pylori; Humans; Infection Control; Infectious Disease Transmission, Patient-to-Professional; Nursing Staff, Hospital; Prevalence; Stomach Diseases; Tobramycin

Sixty nosocomial infections caused by Pseudomonas aeruginosa and Acinetobacter baumannii resistant to aminoglycosides, cephalosporins, quinolones, penicillins, monobactams, and imipenem were treated with colistin (one patient had two infections that are included as two different cases). The infections were pneumonia (33% of patients), urinary tract infection (20%), primary bloodstream infection (15%), central nervous system infection (8%), peritonitis (7%), catheter-related infection (7%), and otitis media (2%). A good outcome occurred for 35 patients (58%), and three patients died within the first 48 hours of treatment. The poorest results were observed in cases of pneumonia: only five (25%) of 20 had a good outcome. A good outcome occurred for four of five patients with central nervous system infections, although no intrathecal treatment was given. The main adverse effect of treatment was renal failure; 27% of patients with initially normal renal function had renal failure, and renal function worsened in 58% of patients with abnormal baseline creatinine levels. Colistin may be a good therapeutic option for the treatment of severe infections caused by multidrug-resistant P. aeruginosa and A. baumannii.

Topics: Acinetobacter Infections; Adolescent; Adult; Aged; Aged, 80 and over; Anti-Bacterial Agents; Child; Child, Preschool; Colistin; Creatinine; Cross Infection; Drug Resistance, Multiple; Female; Humans; Injections, Intravenous; Male; Middle Aged; Pseudomonas Infections

To assess the effectiveness of selective digestive decontamination (SDD) on the control of nosocomial infection (NI) in critically ill pediatric patients.. A prospective, randomized, non-blinded and controlled clinical microbiology study.. The pediatric intensive care unit (PICU) of a tertiary level pediatric university hospital. CRITERIA FOR INCLUSION: Patients 1 month to 14 years old, who underwent some kind of manipulation or instrumentation (mechanical ventilation, vascular cannulation, monitoring of intracranial pressure, thoracic or abdominal drainage, bladder catheterization, peritoneal dialysis, etc.) and/or presented a neurological coma requiring a stay in the PICU of 3 or more days.. Over a period of 2 years, 244 patients met the inclusion criteria; 18 patients were withdrawn because of protocol violation. The treatment group comprised 116 patients and the control group, 110 patients.. The treatment group received a triple therapy of colimycin, tobramycin and nystatin administered orally or via nasogastric tube every 6 hours. All patients with mechanical ventilation or immune-depression received decontamination treatment of the oropharyngeal cavity with hexitidine (Oraldine 0.5 mg/ml) every 6-8 hours in accordance with the PICU's conventional protocol.. Up to 10 types of nosocomial infection were diagnosed following criteria of the Centers for Disease Control (CDC). The severity and manipulation of the patients on admission was assessed using the therapeutic intervention scoring system (TISS) and multi-organ system failure scores (MOSF).. UNIVARIANT ANALYSIS: SDD did not significantly reduce the incidence of NI, antibiotic use, the length of stay, or mortality; although a small percentage of respiratory and urinary tract infections was detected, catheter-related bacteremia was the most common infection. MULTIVARIANT ANALYSIS: Controlling the risk factors for each child through log regression showed that SDD acted as a protective factor for more than 90% of the sample with respect to the appearance of respiratory and urinary tract infections, reducing the risk of such infections to 1/5 and 1/3, respectively.. SDD was effective in controlling respiratory and urinary tract infections in children admitted to the PICU, but it did not reduce the incidence of other types of nosocomial infection.

Topics: Adolescent; Antibiotic Prophylaxis; Child; Child, Preschool; Colistin; Cross Infection; Digestive System; Drug Therapy, Combination; Female; Hexetidine; Humans; Infant; Intensive Care Units, Pediatric; Male; Multiple Organ Failure; Multivariate Analysis; Nystatin; Prospective Studies; Regression Analysis; Respiratory Tract Infections; Severity of Illness Index; Tobramycin; Urinary Tract Infections

To determine the influence of selective oropharyngeal decontamination (SOD) on the rate of colonization and infection of the respiratory tract in intensive care patients requiring mechanical ventilation for more than 4 days. A financial assessment was also performed.. Randomized, prospective, controlled study using amphotericin B, colistin sulfate (polymyxin E), and tobramycin applied to the oropharynx and systemic cefotaxime prophylaxis.. Anesthesiology intensive care unit (ICU) of a 1500-bed hospital.. A total of 88 patients admitted as emergencies and intubated within less than 24 h were enrolled. Fifty-eight patients received SOD and 30 patients served as controls. Randomization was in the proportion of 2 : 1 study patients to controls.. Microbiological samples from the oropharynx and other infected sites were taken at the time of admission, then twice a week and after extubation.. With the use of SOD, colonization was significantly reduced. Furthermore, the infection rate decreased from 77% in the controls to 22% in the study patients. Staphylococcus aureus was the main potential pathogen causing colonization and pneumonia. Number of days in the ICU, duration of ventilation, and mortality were not significantly decreased. The total cost of antibiotics was reduced. Development of resistance was not observed.. The use of SOD significantly reduced the colonization and pneumonia and the total charge for antibiotics. The length of stay in the ICU, duration of ventilation, and mortality were similar. No resistance was observed. Staphylococcus aureus was selected by SOD in some patients and the clinical relevance needs further observation.

Topics: Adult; Amphotericin B; Anti-Bacterial Agents; Colistin; Cross Infection; Drug Resistance, Microbial; Female; Humans; Intensive Care Units; Male; Microbial Sensitivity Tests; Middle Aged; Oropharynx; Pneumonia; Respiration, Artificial; Tobramycin

The aims of the study were to evaluate the technique of selective digestion decontamination (SDD) in preventing the development of nosocomial infections in a selected population and to assess the effects on colonization of the oropharynx, nares, and bronchi. A financial assessment was also performed.. Prospective, double-blind, randomized placebo-controlled trial using amphotericin B, colistin sulfate (polymixin E), and gentamicin applied to the nares, the oropharynx, and enterally; no parenteral antibiotics were given during the study period. The SDD was applied every 6 h during the study period.. Multidisciplinary ICU in a university hospital.. A total of 148 trauma patients admitted emergently and intubated within less than 24 h were enrolled. Seventy-two patients who received placebo and 76 treated patients were analyzed on an "intention-to-treat" basis.. Microbiologic surveillance samples of oropharyngeal and bronchial secretions, urine, and any other potentially infected sites were taken at the time of ICU admission and twice weekly thereafter until discharge from the unit.. With the use of SDD, colonization was significantly reduced in the oropharynx and nares (<0.05) but not in bronchi. However, episodes of bronchopneumonia were significantly reduced (19 in the active group vs 37 in the placebo group; p,0.01). Staphylococcus aureus remained the main potential pathogen causing bronchial colonization and subsequent bronchopneumonia. There was no reduction in the incidence of other infections. Days in the ICU, duration of mechanical ventilation, and mortality rate were unchanged. After the use of SDD, Gram-positive colonization tended to increase and this was mainly due to methicillin-resistant coagulase-negative staphylococci. The total cost of antibiotic therapy ($62,117 [US] in the placebo group and $36,008 in the SDD group) was decreased by 42% with the use of SDD. Clinically important complications of SDD were not encountered.. The use of SDD in this population of trauma patients reduced the incidence of bronchopneumonia and the total charge for antibiotics. Stay in the ICU, mechanical ventilation, and mortality rate were unchanged. Methicillin-resistant coagulase-negative staphylococci were selected by SDD in some patients and the clinical relevance of this colonization needs further evaluation.

Topics: Amphotericin B; Anti-Bacterial Agents; Antibiotic Prophylaxis; Antifungal Agents; Bronchopneumonia; Colistin; Cross Infection; Double-Blind Method; Gentamicins; Humans; Multiple Trauma; Prospective Studies; Treatment Outcome

To determine whether selective decontamination of the digestive tract exerts any long-term effects on antimicrobial resistance patterns.. A surveillance and interventional study comparing the antimicrobial sensitivity patterns of clinically important bacterial isolates the year before a 2-yr, double-blind, randomized, controlled study of selective decontamination of the digestive tract, and for the year thereafter when no use of the regimen was made.. A ten-bed respiratory intensive care unit (ICU) in a 1,200-bed teaching hospital.. All 1,528 patients admitted to the ICU over the 4-yr study period were included. There were 406 patients admitted in the year before the study of decontamination of the digestive tract (65% medical, 23% surgical, and 12% trauma), of whom 76% required mechanical ventilation. There were 719 patients admitted during the 2-yr study of selective decontamination (55% medical, 28% surgical, and 17% trauma), of whom 79.6% required mechanical ventilation. There were 403 patients admitted in the subsequent year (61% medical, 25% surgical, and 14% trauma), of whom 76.9% required mechanical ventilation.. We performed daily clinical monitoring to detect nosocomial infection, with microbiological investigation when clinically indicated, as well as twice-weekly routine microbiological surveillance sampling. Antimicrobial susceptibility testing using standard laboratory methods was also performed. Selective decontamination of the digestive tract included parenteral cefotaxime and oral and enteral polymyxin E, amphotericin B, and tobramycin.. The occurrence rate of nosocomial infection was 20.6%, 16.6%, and 25.3%, respectively, in the three study periods. In the year after selective decontamination, there was an increase in the occurrence rate of infection (p = .005), with an-associated increase in infections caused by the Enterobacteriaceae, while a reduction in the level of resistance to the third-generation cephalosporins were found (p = .07). There was a progressive increase in the occurrence rate of infections caused by Acinetobacter species (p = .05). Only 11 infections over the 4 yrs were caused by Enterococcus species. Staphylococcal infections were uncommon (5.7% of admissions), and the level of methicillin resistance did not change. No increase in aminoglycoside resistance occurred.. No long-term effects on antimicrobial resistance or the spectrum of nosocomial pathogens could be attributed to the use of selective decontamination of the digestive tract over a 2-yr period in a respiratory ICU admitting all categories of patients.

Topics: Adult; Amphotericin B; APACHE; Bacteria; Cefotaxime; Colistin; Cross Infection; Digestive System; Double-Blind Method; Drug Resistance, Microbial; Drug Therapy, Combination; Female; Humans; Intensive Care Units; Male; Prospective Studies; Respiration, Artificial; Tobramycin

The role of selective decontamination of the digestive tract (SDD) for the prevention of nosocomial infection in critically ill patients remains controversial, and the efficacy of this technique in patients who are already infected on presentation to the intensive care unit has not previously been assessed. We performed a double-blind randomized placebo controlled trial of SDD (parenteral cefotaxime, six-hourly oral and enteral polymyxin E, tobramycin, and amphotericin B vs placebo) for all infected patients presenting to the ICU requiring mechanical ventilation for more than 48 hours and ICU stay of more than 5 days. Daily clinical and microbiological monitoring for secondary infection was undertaken until hospital discharge. In all, 59 selective decontamination and 76 placebo fully comparable patients fulfilled criteria for enrollment and analysis (APACHE II 15.2 vs 15.1). The number of patients receiving SDD who developed nosocomial infections was significantly reduced (P = 0.048), and there were no infections caused by the enterobacteriaceae or Candida spp in this group. No difference in ICU (17.5 vs 18.8 days) or hospital stay (32.7 vs 34.2 days) or mortality (17% vs 22.3%) was shown. Critically ill, primarily infected patients are protected from nosocomial infection by the use of SDD.

Topics: Administration, Oral; Adult; Amphotericin B; Cefotaxime; Colistin; Critical Care; Critical Illness; Cross Infection; Digestive System; Double-Blind Method; Drug Therapy, Combination; Female; Humans; Intensive Care Units; Length of Stay; Male; Middle Aged; Placebos; Prospective Studies; Respiration, Artificial; Survival Rate; Tobramycin

A randomized, double-blind, placebo-controlled trial of selective decontamination of the oropharynx and gastrointestinal tract was conducted on 61 intubated patients in a medical-surgical intensive care unit (ICU) to determine the impact on nosocomial pneumonia, other infections, and emergence of colonization or infection with antibiotic-resistant bacteria. Over 8 months, 30 patients received an oral paste and solution containing polymyxin, gentamicin, and nystatin; 31 patients received a placebo paste and solution. At study entry, patients in both groups were seriously ill (mean acute physiologic score, 27.2), frequently had pulmonary infiltrates (73.8%), and were likely to be receiving systemic antibiotics (86.9%). There were no differences between study patients and control patients in these characteristics or in frequency of any nosocomial infection (50% vs. 55%), nosocomial pneumonia (27% vs. 26%), febrile days (2.3 vs. 2.0), duration of antibiotic therapy (14.0 vs. 13.4), or mortality rates (37% vs. 48%). There was no difference in infections caused by antibiotic-resistant gram-negative bacilli, although a trend towards more frequent infection with gentamicin-resistant enterococci was found for study patients. Selective decontamination did not appear to be effective in our very ill medical-surgical ICU patients, although the number of patients in our trial was sufficient to detect only a 50% or greater reduction in pneumonia rates.

Topics: Colistin; Cross Infection; Decontamination; Double-Blind Method; Drug Resistance, Microbial; Female; Gentamicins; Humans; Intensive Care Units; Male; Middle Aged; Nystatin; Pneumonia, Bacterial; Prospective Studies

Topics: Administration, Oral; Amphotericin B; Anti-Bacterial Agents; Colistin; Cross Infection; Double-Blind Method; Gastroenteritis; Humans; Intestinal Mucosa; Tobramycin

The influence of topical antimicrobial prophylaxis (TAP) on colonization of oropharynx and trachea was studied in patients receiving and not receiving prophylaxis. Twenty-two patients in Intensive Care Unit (ICU) I (Group 1) received TAP (tobramycin, colistin, and amphotericine B in oropharynx and stomach). Simultaneous to Group 1, 21 patients (Group 2) not receiving TAP were studied in ICU I. A control group of patients admitted to another, identical, ICU (ICU II), where no TAP was administered, were studied simultaneously (Group 3a, n = 23). A second control group (Group 3b, n = 31), was formed by collecting data from patients admitted to ICU I in Period II. Patients receiving TAP were less frequently colonized than patients not receiving prophylaxis. Moreover, of the patients not receiving TAP, those staying in the ICU where TAP was administered (Group 2) were less frequently colonized than patients in another ICU (Group 3). Of the patients not colonized on admission, those staying in the ICU where TAP was administered remained free of colonization for a longer time. In the ICU where no TAP was administered, more patients were colonized simultaneously and cross-acquisition occurred more frequently. TAP significantly influenced colonization of oropharynx and trachea in patients receiving and not receiving prophylaxis within the same ICU as compared with patients not receiving prophylaxis in another identical ICU.

Topics: Administration, Topical; Aged; Amphotericin B; Colistin; Colony Count, Microbial; Cross Infection; Drug Therapy, Combination; Enterobacteriaceae; Female; Humans; Intensive Care Units; Male; Middle Aged; Oropharynx; Prospective Studies; Pseudomonadaceae; Respiratory Tract Infections; Tobramycin; Trachea

Selective decontamination of the digestive tract with topical nonabsorbable antibiotics has been reported to prevent nosocomial infections in patients receiving mechanical ventilation, and the procedure is used widely in Europe. However, it is unclear whether selective decontamination improves survival.. We conducted a randomized, double-blind multicenter study in which 445 patients receiving mechanical ventilation in 15 intensive care units were given either prophylactic nonabsorbable antibiotics (n = 220) or a placebo (n = 225). Topical antibiotics (tobramycin, colistin sulfate, and amphotericin B) or a placebo was administered through a nasogastric tube and applied to the oropharynx throughout the period of ventilation. The main end points were the mortality rate in the intensive care unit and within 60 days of randomization.. A total of 142 patients died in the intensive care unit; 75 (34 percent) in the treatment group and 67 (30 percent) in the placebo group (P = 0.37). Mortality within 60 days of randomization was similar in the two groups (P = 0.40), even after adjustment for factors that were either unbalanced or individually predictive of survival in the two groups (P = 0.70). Pneumonia developed in 59 patients (13 percent) in the intensive care unit within 30 days of enrollment in the study (33 in the placebo group and 26 in the treatment group, P = 0.42). Pneumonia acquired in the intensive care unit and due to gram-negative bacilli was less frequent (P = 0.01) in the treatment group than in the placebo group. The total charges for antibiotics were 2.2 times higher in the treatment group.. Selective decontamination of the digestive tract does not improve survival among patients receiving mechanical ventilation in the intensive care unit, although it substantially increases the cost of their care.

Topics: Administration, Topical; Amphotericin B; Anti-Bacterial Agents; Colistin; Critical Care; Cross Infection; Digestive System; Double-Blind Method; Female; Gram-Negative Bacterial Infections; Humans; Intensive Care Units; Male; Middle Aged; Multiple Organ Failure; Pneumonia; Respiration, Artificial; Survival Rate; Time Factors; Tobramycin

To study the effect of enterally administered polymyxin E, tobramycin, and amphotericin B (selective flora suppression) on bacterial colonization, infection, resistance, and mortality rate.. Prospective, consecutive crossover controlled study.. Two surgical ICUs in a university hospital; ICU I with ten beds, ICU II with eight beds.. Two hundred patients entered the 1-yr trial. Fifty of 111 patients received selective flora suppression during the first 6 months in ICU I (test group), while 61 of 111 patients served as the control group in the following 6 months. In ICU II, 49 of 89 patients received no selective flora suppression in the first 6 months (control group), followed by 40 of 89 patients receiving selective flora suppression during the second 6-month period (test group).. The test group got a mixture of nonabsorbable antibiotics (paste and suspension) in the digestive tract. The control group received paste and suspension without antimicrobial agents. All 200 patients received cefotaxime during the first 4 days.. With the use of selective flora suppression, colonization with aerobic Gram-negative bacilli was significantly (p less than .01) reduced. There was also a significant reduction in nosocomial bronchopulmonary (ICU I and II; p less than .001) and urinary tract (ICU II; p less than .001) infections. The difference in mortality was not significant. There was no development of resistance against the antibiotics used during the limited period evaluated.. Selective flora suppression is effective in reducing secondary colonization by aerobic Gram-negative bacilli. Reduction of bronchopulmonary and urinary tract infections most likely occurs with colonization prevention.

Topics: Administration, Oral; Adult; Aged; Amphotericin B; Bacterial Infections; Bronchopneumonia; Colistin; Critical Care; Cross Infection; Female; Gram-Negative Aerobic Bacteria; Humans; Intensive Care Units; Male; Middle Aged; Mortality; Mouth; Ointments; Prospective Studies; Sepsis; Suspensions; Tobramycin; Urinary Tract Infections

A double blind, placebo-controlled trial was performed to test the efficacy of prevention of nosocomial infections by selective digestive decontamination. Placebo or tobramycin (80 mg) and colistin (100 mg) was given four times daily via the gastric tube. Amphotericin B (500 mg/6 h) was administered to all patients. As our ICU is divided into two separate subunits, intestinal decontamination or placebo was administered alternatively to patients of the two subunits during two 3-month periods, separated by a 2-month period without prevention. The decontamination (n = 97) and placebo groups (n = 84) were similar with respect to age, sex, severity score and diagnostic categories on admission. Intestinal decontamination alone failed to significantly reduce the number of infected patients (26% vs 34.5%, p = 0.20), but was effective on ICU-acquired infections (0.33 vs 0.60, p = 0.02) especially gram-negative infection rates (0.17 vs 0.43, p = 0.01). The onset of the first ICU-acquired infection was delayed (9 vs 13 days, p less than 0.001) and incidence of pneumonia (2 vs 13 cases, p less than 0.01) including bacterial pneumonia (0 vs 8 cases, p less than 0.01) was significantly decreased. However, mean ICU stay and mortality were not significantly modified by intestinal decontamination.

Topics: Amphotericin B; Clinical Protocols; Colistin; Cross Infection; Double-Blind Method; Female; Humans; Intensive Care Units; Intestinal Diseases; Length of Stay; Male; Middle Aged; Pneumonia; Prospective Studies; Tobramycin

A comparative, prospective study was made of the incidence of infection in the lower airway (purulent tracheobronchitis and pneumonia) in long-term patients who were mechanically ventilated due to respiratory failure of noninfectious origin. Twenty-eight patients were randomly allocated into a study group (A, n = 13) in which a nonabsorbable paste containing 2% tobramycin, 2% amphotericin B, and 2% polymyxin E was administered locally to decontaminate the oropharynx, and a control group (B, n = 15) in which a paste without antibiotics was also applied to the oropharynx. We studied the effectiveness of the prophylactic technique in decontaminating the oropharynx and trachea of organisms potentially pathogenic for the respiratory system. Decontamination was successful in ten of 13 patients in group A vs. one of 15 patients in group B (p less than .001). The results demonstrated a lower rate of infection in the lower respiratory tract in the study group (three patients with tracheobronchitis and no pneumonias) than in the control group (three patients with tracheobronchitis and 11 with pneumonia), the difference between both being highly significant (p less than .001). Two (15%) patients in group B developed sepsis of pulmonary origin. None of the patients on prophylactic treatment developed this complication. Although the overall mortality was similar in both groups (group A, 30% vs. group B, 33%), we believe that infection contributed to a great extent to the death of two of five patients in group B. We conclude that nosocomial pneumonia, which is a frequent complication in critically ill patients on mechanical ventilation, could be prevented by local application of nonabsorbable antibiotics to the oropharynx.

Topics: Administration, Topical; Adolescent; Adult; Aged; Amphotericin B; Child; Colistin; Cross Infection; Drug Therapy, Combination; Female; Humans; Male; Middle Aged; Oropharynx; Prospective Studies; Respiration, Artificial; Respiratory Tract Infections; Tobramycin

To study the efficacy of intestinal decontamination by oral nonabsorbable antibiotic agents to control a nosocomial outbreak of intestinal colonization and infection with multiresistant Enterobacteriaceae, and to examine its effects on endemic nosocomial infection rates.. A 10-week prospective incidence study (group 1), and then an 8-week randomized, open trial of intestinal decontamination (groups 2 and 3).. A medical intensive care unit of a tertiary care university hospital.. Consecutive patients with unit stay of over 2 days and a severity score at admission of more than 2; 124 patients were included in group 1, 50 in group 2 (control), and 36 in group 3 (intestinal decontamination).. Neomycin, polymyxin E, and nalidixic acid were given to group 3 patients throughout their stay in the unit.. Intestinal colonization with multiresistant strains occurred in 19.6% of patients in group 1, at a mean of 16 days after admission, and preceded detection in clinical samples by a mean of 11 days. During the decontamination trial, intestinal colonization rates decreased to 10% (group 2), and 3% (group 3) (P = 0.12 and P less than 0.01, compared with group 1, respectively). Corresponding infection rates were 9% (group 1), 3% (group 2), and 0 (group 3). No new cases were detected in the following 4 months. The intestinal colonization rate with gram-positive cocci was higher in group 3 than group 2 (P less than 0.001). The overall rate of nosocomial infections was at 28% (group 1), 33% (group 2), and 32% (group 3).. Intestinal decontamination can help to control an outbreak of intestinal colonization and infection with multiresistant gram-negative bacilli in the intensive care unit, but should not be recommended for routine prevention of endemic nosocomial infections.

Topics: Adult; Aged; Anti-Bacterial Agents; Cephalosporins; Colistin; Cross Infection; Disease Outbreaks; Drug Resistance, Microbial; Drug Therapy, Combination; Enterobacteriaceae; Enterobacteriaceae Infections; Humans; Intensive Care Units; Intestines; Klebsiella pneumoniae; Middle Aged; Nalidixic Acid; Neomycin; Paris; Random Allocation; Risk Factors

The question to be answered in this study was: Is prophylactic selective florasuppression advantageous compared to conventional antibiotic policy as far as microbial colonisation, infection, mortality and development of resistance are concerned? A prospective, consecutive, placebo-controlled study in two ICU's was carried out during four 6-months periods. 200 patients who were intubated for at least 3 days, required intensive care for a minimum of 5 days, and belonged to either class III or IV according to the "Therapeutic Intervention Scoring System" were included in the study. They received either placebo or the prophylaxis regimen described by Stoutenbeek et al., consisting of polymyxin E, tobramycin and amphotericin B. Oropharyngeal, tracheobronchial and rectal colonisation with aerobic gram-negative bacilli markedly decreased in the test groups. The rates of nosocomial bronchopulmonary infections (ICU I and II) and urinary tract infections (ICU II) were significantly reduced. There was no significant reduction in wound infection, septicaemia and mortality rates. No development of resistance and no increase of multi-resistant strains occurred. Selective florasuppression is effective in reducing infection rates in critically ill patients without development of resistant strains.

Topics: Adult; Aged; Amphotericin B; Bacterial Infections; Bronchopneumonia; Clinical Trials as Topic; Colistin; Cross Infection; Drug Therapy, Combination; Female; Humans; Intensive Care Units; Male; Prospective Studies; Risk Factors; Sepsis; Surgical Wound Infection; Tobramycin; Urinary Tract Infections

In a prospective randomized study to determine whether prevention of colonization of Gram-negative bacteria results in prevention of Gram-negative bacterial infections, 96 intensive care patients were randomly allocated into a control group and a study group. The study group received oral nonabsorbable antimicrobial agents (i.e., tobramycin, amphotericin B, and polymyxin E) in addition to parenteral antibiotics. Colonization with Gram-negative microorganisms in the oropharynx, and respiratory and digestive tracts increased in the control group during their stay, while the study group did not tend to colonize with Gram-negative bacteria. In the control group, 107 nosocomial infections were diagnosed, vs. 42 nosocomial infections in the study group. Nosocomial infections caused by Gram-negative bacteria were significantly less frequent in the study group. Mortality due to an acquired infection was significantly less frequent in the study group. We conclude that colonization, infection, and subsequent mortality by nosocomial Gram-negative bacteria can be prevented by a regime of topically applied nonabsorbable antibiotics.

Topics: Adult; Aged; Aged, 80 and over; Amphotericin B; Anti-Bacterial Agents; Bacteria; Cefotaxime; Child; Colistin; Cross Infection; Digestive System; Drug Therapy, Combination; Enterobacteriaceae Infections; Female; Humans; Male; Middle Aged; Oropharynx; Prospective Studies; Pseudomonas Infections; Random Allocation; Respiratory System; Tobramycin

30 patients with acute leukaemia being treated with cytotoxic drugs were investigated in a randomised trial to determine whether oral administration of co-trimoxazole in addition to non-absorbable antibiotics would reduce the rate of infection. Three significant differences were observed between the co-trmoxazole and the control groups: (i) 15 of the 16 (94%) control patients but only 8 of the 14 (57%) patients on co-trimoxazole developed infections and required additional antibiotics intravenously; (ii) although the duration of severe neutropenia (neutrophils less than 0.1 times 10(9)/1) was similar in the two groups, control patients required intravenous antibiotics on average after 2 days of neutropenia, whereas patients receiving co-trimoxazole required these only after 12 days; and (iii) the only 2 patients who died of infection were in the control group. Prophylaxis with co-trimoxazole is important in preventing or delaying the development of infection in neutropenic patients receiving therapy for acute leukaemia.

Topics: Administration, Oral; Adolescent; Adult; Aged; Clinical Trials as Topic; Colistin; Cross Infection; Drug Combinations; Drug Therapy, Combination; Framycetin; Humans; Leukemia, Lymphoid; Leukemia, Myeloid, Acute; Middle Aged; Neutropenia; Nystatin; Prospective Studies; Research Design; Sulfamethoxazole; Trimethoprim

The coinfection process producing multiple species of pathogens provides a specific ecological niche for the exchange of genetic materials between pathogens, in which plasmids play a vital role in horizontal gene transfer, especially for drug resistance, but the underlying transfer pathway remains unclear. Interspecies communication of the plasmids associated with the transfer of third-generation cephalosporins, quinolones, and colistin resistance has been observed in simultaneously isolated Escherichia coli and Klebsiella pneumoniae from abdominal drainage following surgery. The MICs of antimicrobial agents were determined by the broth microdilution method. The complete chromosome and plasmid sequences were obtained by combining Illumina paired-end short reads and MinION long reads. S1-PFGE, southern blot analysis and conjugation assay confirmed the transferability of the

Topics: Anti-Bacterial Agents; beta-Lactamases; Cephalosporins; Coinfection; Colistin; Communication; Cross Infection; Drug Resistance, Bacterial; Escherichia coli; Escherichia coli Proteins; Humans; Klebsiella Infections; Klebsiella pneumoniae; Microbial Sensitivity Tests; Plasmids; Quinolones

This study was aimed to evaluate the antibiotic resistance, biofilm formation, and genetic diversity of carbapenem-resistant Pseudomonas aeruginosa (CRPA) strains isolated from four types of nosocomial infections (NIs) including urinary tract infection (UTI), ventilator-associated pneumonia (VAP), surgical site infection (SSI), and bloodstream infection (BSI).. In total, 115 isolates of NIs-causing P. aeruginosa were collected from NIs. Antibiotic susceptibility testing (AST) was performed using disk diffusion method and minimum inhibitory concentrations. Biofilm formation was tested on 96-well polystyrene microtiter plates (MTP). CRPA isolates were genotyped using multiple-locus variable number of tandem repeat analysis (MLVA). The most resistance and susceptibility rates were observed to amikacin (70.6%) and colistin (96.1%), respectively. Colistin and meropenem were the most active antimicrobial agents in VAP, SSI, and BSI. While, colistin and cefepime were the most active in UTIs. In total, 52.2% (n = 60/115) of P. aeruginosa isolates were carbapenem resistant, of which 95.0%, 55.0%, and 5.0% were multidrug-resistant, extensively drug-resistant, and pandrug-resistant, respectively. There was a significant association between resistance to carbapenem and resistance to other antibiotics except for piperacillin/tazobactam. The biofilm production of CRPA isolates was 95.0%, of which 23.3% were strong biofilm producers. Based on MLVA, there were 34 different types of CRPA isolates classified into three main clusters and 5 sub clusters.. The association of CRPA with other antibiotic resistance, the high rates of biofilm production, and the high genetic diversity of the isolates may be a warning of the need for a careful surveillance program.

Topics: Anti-Bacterial Agents; Biofilms; Carbapenems; Colistin; Cross Infection; Drug Resistance, Microbial; Genetic Variation; Humans; Iran; Microbial Sensitivity Tests; Pseudomonas aeruginosa; Pseudomonas Infections

Multidrug-resistant Acinetobacter baumannii is an important causal pathogen of healthcare-associated infections, and colistin-resistant strains have recently emerged owing to the increased use of colistin. Using next-generation sequencing (NGS), a single whole-genome sequencing (WGS) protocol can identify and type pathogens, analyze genetic relationships among different pathogens, predict pathogenic transmissions, and detect antibiotic resistance genes. However, only a few studies have applied NGS in studying the resistance mechanism and epidemiology of colistin-resistant A. baumannii. This study aimed to elucidate the resistance mechanism of colistin-resistant A. baumannii and analyze its molecular epidemiology through WGS.. The subjects in this study were patients who visited a university hospital between 2014 and 2018. Thirty colistin-resistant strains with high minimum inhibitory concentrations were selected from various patient samples, and WGS was performed. Comparative genomic analysis was performed for the 27 colistin-resistant A. baumannii strains using a colistin-susceptible strain as the reference genome.. The WGS analysis found no mutation for lpxA, lpxC, lpx D, pmrA, pmrB, and mcr1, the genes known to be associated with colistin resistance. Fifty-seven coding sequences (CDS) showed differences; they included 13 CDS with known names and functions that contained 21 genes. From the whole-genome multi-locus sequence typing (wgMLST) and single nucleotide polymorphism (SNP) analyses, two major clusters were found for the colistin-resistant A. baumannii strains. However, no differences were observed by the time of detection for each cluster, the samples, the pattern of antibiotic resistance, or the patient characteristics. In the conventional MLST following the Oxford scheme, the typing result showed ST1809, ST451, ST191, ST1837, and ST369 in the global clone 2 (GC2), without any relation with the results of wgMLST and SNP analyses.. Based on the findings of the resistance gene analysis through WGS and comparative genomic analysis, the potential genes associated with colistin-resistance or CDS were examined. Furthermore, the analysis of molecular epidemiology through WGS regarding colistin-resistant A. baumannii may prove helpful in preventing infection by multidrug-resistant bacteria and controlling healthcare-associated infections.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; Bacterial Proteins; Colistin; Cross Infection; Drug Resistance, Bacterial; Humans; Microbial Sensitivity Tests; Multilocus Sequence Typing

Enterobacter kobei is an emerging cause of outbreak of nosocomial infections in neonatal intensive care units (NICUs). Between July and September 2016, a NICU in a tertiary care hospital of Nepal observed an abrupt increase in the number of neonatal sepsis cases caused by Enterobacter spp. infecting 11 out of 23 admitted neonates, five of whom died of an exacerbated sepsis.. To confirm the suspected outbreak, identify environmental source of infection, and characterize genetic determinants of antimicrobial resistance (AMR) and virulence of the pathogen.. Whole-genome sequencing of all Enterobacter spp. isolated from blood cultures of septic neonates admitted to NICU between May 2016 and December 2017 was performed. Also, an environmental sampling was intensified from fortnightly to weekly during the outbreak.. The genomic analysis revealed that 10 out of 11 non-duplicated E. kobei isolated from neonatal blood cultures between July and September 2016 were clonal, confirming the outbreak. The isolates carried AMR genes including bla. Our study underscored the need to implement stringent infection control measures to prevent infection outbreaks. For the first time, we report the emergence of carbapenem and colistin non-susceptible E. kobei carrying mcr-10 gene as a cause of nosocomial neonatal sepsis in a NICU.

Topics: Carbapenems; Colistin; Cross Infection; Disease Outbreaks; Enterobacter; Enterobacteriaceae Infections; Humans; Infant, Newborn; Intensive Care Units, Neonatal; Microbial Sensitivity Tests; Neonatal Sepsis; Nepal; Tertiary Care Centers

Nosocomial pneumonia caused by carbapenem-resistant gram-negative bacteria (CRGNB) is a growing threat due to the limited therapeutic choices and high mortality rate. The aim of this study was to evaluate the prognostic factors for mortality in patients with nosocomial pneumonia caused by CRGNB and the impact of colistin-based therapy on the outcomes of intensive care unit (ICU) patients. We conducted a retrospective study of the ICUs in five tertiary teaching hospitals in Taiwan. Patients with nosocomial pneumonia caused by CRGNB from January 2016 to December 2016 were included. Prognostic factors for mortality were analyzed using multivariate logistic regression. The influence of colistin-based therapy on mortality and clinical and microbiological outcomes were evaluated in subgroups using different severity stratification criteria. A total of 690 patients were enrolled in the study, with an in-hospital mortality of 46.1%. The most common CRGNB pathogens were Acinetobacter baumannii (78.7%) and Pseudomonas aeruginosa (13.0%). Significant predictors (odds ratio and 95% confidence interval) of mortality from multivariate analysis were a length of hospital stay (LOS) prior to pneumonia of longer than 9 days (2.18, 1.53-3.10), a sequential organ failure assessment (SOFA) score of more than 7 (2.36, 1.65-3.37), supportive care with vasopressor therapy (3.21, 2.26-4.56), and escalation of antimicrobial therapy (0.71, 0.50-0.99). There were no significant differences between the colistin-based therapy in the deceased and survival groups (42.1% vs. 42.7%, p = 0.873). In the subgroup analysis, patients with multiple organ involvement (> 2 organs) or higher SOFA score (> 7) receiving colistin-based therapy had better survival outcomes. Prolonged LOS prior to pneumonia onset, high SOFA score, vasopressor requirement, and timely escalation of antimicrobial therapy were predictors for mortality in critically ill patients with nosocomial CRGNB pneumonia. Colistin-based therapy was associated with better survival outcomes in subgroups of patients with a SOFA score of more than 7 and multiple organ involvement.

Topics: Acinetobacter baumannii; Anti-Bacterial Agents; Carbapenems; Colistin; Critical Illness; Cross Infection; Gram-Negative Bacteria; Healthcare-Associated Pneumonia; Humans; Retrospective Studies

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; Cancer Care Facilities; Carbapenems; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Egypt; Hospitals, Pediatric; Humans; Microbial Sensitivity Tests; Multilocus Sequence Typing; Whole Genome Sequencing

Genomic surveillance can inform effective public health responses to pathogen outbreaks. However, integration of non-local data is rarely done. We investigate two large hospital outbreaks of a carbapenemase-carrying

Topics: Bacterial Proteins; Colistin; Cross Infection; Disease Outbreaks; Drug Resistance, Bacterial; Epidemiological Monitoring; Germany; Humans; Klebsiella Infections; Klebsiella pneumoniae; Membrane Transport Proteins; Models, Molecular; Phylogeny; Protein Conformation

Acinetobacter baumannii complex are microorganisms of critical priority of resistance, being associated with higher costs and negative outcomes for hospitalized patients. Thus, the study aimed to analyse the factors associated with A. baumannii complex infection in various hospital sectors.. This is a case-control study that included patients hospitalized from January 2017 to June 2019. Demographic, microbiological and clinical variables were collected from each patient. All cases had positive culture results for A. baumannii complex resistant to more than three classes of antimicrobials. Carbapenem-resistance was examined by the disk diffusion test, while the broth microdilution method was used to determine the susceptibility to colistin.. A. baumannii complex infection was mostly present in ICU (74.2%) than in other hospital areas. The bacteria was also linked with the length of hospitalization until the results for the culture (OR = 1.13; 95% CI: 1.06 - 1.21; p < 0.001) and with pneumonia associated with mechanical ventilation (OR = 4.48; 95% CI: 1.55 - 13.00; p = 0.006). Moreover, patients exposed to infection with multidrug-resistant A. baumannii complex had higher risks of death (OR = 3.25; 95% CI: 1.06 - 9.91; p = 0.039).. This study provides evidence that A. baumannii complex infection is associated with the number of days of hospitalization up to culture positivity, pneumonia associated with the use of mechanical ventilation and death. Infections appear to be more critical in ICU when compared to other areas. Taken together, these findings could support hospital infection surveillance programs, as well as prevention measures to reduce mortality rates and other complications.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Adolescent; Adult; Aged; Aged, 80 and over; Anti-Bacterial Agents; Brazil; Carbapenems; Case-Control Studies; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Female; Hospitals; Humans; Intensive Care Units; Length of Stay; Male; Microbial Sensitivity Tests; Middle Aged; Pneumonia; Risk Factors; Young Adult

Acinetobacter baumannii has emerged as one of the common multidrug resistance pathogens causing hospital-acquired infections. This study was conducted to elucidate the distribution of antimicrobial resistance genes in the bacterial population in Thailand. Multidrug-resistant A. baumannii (MDR A. baumannii) isolates were characterized phenotypically, and the molecular epidemiology of clinical isolates in 11 tertiary hospitals was investigated at a country-wide level.. A total of 135 nonrepetitive MDR A. baumannii isolates collected from tertiary care hospitals across 5 regions of Thailand were examined for antibiotic susceptibility, resistance genes, and sequence types. Multilocus sequence typing (MLST) was performed to characterize the spread of regional lineages.. ST2 belonging to IC2 was the most dominant sequence type in Thailand (65.19%), and to a lesser extent, there was also evidence of the spread of ST164 (10.37%), ST129 (3.70%), ST16 (2.96%), ST98 (2.96%), ST25 (2.96%), ST215 (2.22%), ST338 (1.48%), and ST745 (1.48%). The novel sequence types ST1551, ST1552, ST1553, and ST1557 were also identified in this study. Among these, the blaoxa-23 gene was by far the most widespread in MDR A. baumannii, while the blaoxa-24/40 and blaoxa-58 genes appeared to be less dominant in this region. The results demonstrated that the predominant class D carbapenemase was blaOXA-23, followed by the class B carbapenemase blaNDM-like, while the mcr-1 gene was not observed in any isolate. Most of the MDR A. baumannii isolates were resistant to ceftazidime (99.23%), gentamicin (91.85%), amikacin (82.96%), and ciprofloxacin (97.78%), while all of them were resistant to carbapenems. The results suggested that colistin could still be effective against MDR A. baumannii in this region.. This is the first molecular epidemiological analysis of MDR A. baumannii clinical isolates at the national level in Thailand to date. Studies on the clonal relatedness of MDR A. baumannii isolates could generate useful data to understand the local epidemiology and international comparisons of nosocomial outbreaks.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; Carbapenems; Ciprofloxacin; Clone Cells; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Humans; Microbial Sensitivity Tests; Molecular Epidemiology; Multilocus Sequence Typing; Thailand

Topics: Anti-Bacterial Agents; Colistin; Cross Infection; Healthcare-Associated Pneumonia; Hospitals; Humans; Pneumonia, Ventilator-Associated

Nosocomial meningitis caused by Gram-negative bacteria is associated with increasingly common neurosurgical procedures in children, with an increase in incidence recently reported. These infections are associated with an increased risk of mortality, prolonged hospitalisation, and increased costs. In this report, we describe two paediatric cases with central nervous system infections caused by extensively drug-resistant Gram-negative bacteria that were successfully treated with intraventricular colistin. To the best of our knowledge, this is the first comprehensive review and discussion of intraventricular antimicrobial therapy in a paediatric population. Based on our comprehensive review of the relevant literature, it appears that intraventricular administration of colistin may be a promising and effective option in the treatment of central nervous system infections in children who do not respond to other treatment options.

Topics: Acinetobacter Infections; Anti-Bacterial Agents; Child, Preschool; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Female; Humans; Infant; Injections, Intraventricular; Male; Meningitis, Bacterial; Pseudomonas Infections

BackgroundFrance is a low prevalence country for colistin resistance. Molecular and epidemiological events contributing to the emergence of resistance to colistin, one of the 'last-resort' antibiotics to treat multidrug-resistant Gram-negative infections, are important to investigate.AimThis retrospective (2014 to 2017) observational study aimed to identify risk factors associated with acquisition of colistin-resistant

Topics: Anti-Bacterial Agents; Bacterial Proteins; Clone Cells; Colistin; Cross Infection; Drug Resistance, Bacterial; Epidemics; France; Hospitals; Humans; Klebsiella Infections; Klebsiella pneumoniae; Male; Microbial Sensitivity Tests; Retrospective Studies; Risk Factors

To compare the effectiveness and safety of aerosolized (AER) plus intravenous (IV) colistin with IV colistin alone in patients with nosocomial pneumonia (NP) due to multidrug-resistant (MDR) Gram-negative bacteria.. This was a retrospective cohort study of adults with NP who received IV colistin alone or in combination with AER colistin. The primary endpoint was clinical cure at end of therapy. Secondary endpoints included microbiological eradication, in-hospital mortality and nephrotoxicity.. In total, 135 patients were included in this study: 65 patients received AER plus IV colistin and 70 patients received IV colistin alone. Baseline characteristics were similar between the two groups. Clinical cure was achieved in 42 (65%) patients who received AER plus IV colistin and 26 (37%) patients who received IV colistin alone (P = 0.01). Among a total of 88 patients who were microbiologically evaluable, 27 (42%) patients who received AER plus IV colistin and 12 (17%) patients who received IV colistin alone attained favourable microbiological outcomes (P = 0.022). In-hospital mortality (43% vs 59%, P = 0.072) was higher in patients who received IV colistin alone, but the difference was not significant. Renal injury occurred in 31% of patients who received AER plus IV colistin and in 41% of patients who received IV colistin alone (P = 0.198).. AER colistin can be considered as salvage therapy as an adjunct to IV administration for the treatment of patients with NP due to MDR Gram-negative pathogens.

Topics: Administration, Inhalation; Adult; Anti-Bacterial Agents; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Gram-Negative Bacteria; Gram-Negative Bacterial Infections; Healthcare-Associated Pneumonia; Humans; Pneumonia, Ventilator-Associated; Retrospective Studies; Treatment Outcome

Studying time-related changes in susceptible pathogens causing healthcare-associated infections (HAIs) is vital in improving local antimicrobial and infection control practices.. Describe susceptibility patterns to several antimicrobials in gram-positive and gram-negative pathogens isolated from patients causing HAIs at three private tertiary care hospitals in Saudi Arabia over a 5-year period.. Data on trends of antimicrobial susceptibility among bacteria causing HAIs events in children and adults at three tertiary private hospitals located in Riyadh and Qassim, Saudi Arabia, were collected retrospectively between 2015 and 2019 using the surveillance data datasets.. Over a 5-year period, 38,624 pathogens caused 17,539 HAI events in 17,566 patients. About 9450 (53.8%) of patients who suffered HAIs were females and the average age was 41.7 ± 14.3 years (78.1% were adults and 21.9% were children). Gram-negative pathogens were 2.3-times more likely to cause HAIs compared to gram-positive bacteria (71.9% vs. 28.1%). The ranking of causative pathogens in decreasing order was: Escherichia coli (38%), Klebsiella species (15.1%), and Staphylococcus aureus (12.6%). Gram-positive isolates were mostly susceptible to linezolid (91.8%) whereas they were resistant to ampicillin (52.6%), cefoxitin (54.2%), and doxycycline (55.9%). Gram-negative isolates were mostly sensitive to tigecycline (95%) whereas they were resistant to cefotaxime (49.5%) and cefixime (59.6%). During the 5 years, there were relatively stable susceptibility patterns to all tested antimicrobials, except for cefotaxime which shown a susceptibility reduction by 41.4%, among Escherichia coli and Klebsiella species. An increase in the susceptibility of Acinetobacter and Enterobacter and Citrobacter species to all studied antimicrobials was observed except for colistin that had a slight sensitivity reduction in 2019 by 4.3% against Acinetobacter species. However, we noted reduced sensitivity of MRSA, CoNS and Enterococcus species to gentamicin; and increased resistance of MRSA to linezolid and vancomycin.. The observed increase in susceptibility of gram-positive and gram-negative bacteria to studied antimicrobials is important; however, reduced sensitivity of MRSA, CoNS and Enterococcus species to gentamicin; and increased resistance of MRSA to linezolid and vancomycin is a serious threat and calls for effective antimicrobial stewardship programs.

Topics: Adult; Anti-Bacterial Agents; Colistin; Cross Infection; Delivery of Health Care; Drug Resistance, Multiple, Bacterial; Female; Gram-Negative Bacteria; Gram-Positive Bacteria; Hospitals; Humans; Linezolid; Male; Microbial Sensitivity Tests; Middle Aged; Retrospective Studies; Saudi Arabia; Sensitivity and Specificity; Tigecycline; Vancomycin

Pseudomonas aeruginosa cross-infections are related to increased morbidity and mortality in cystic fibrosis (CF).. The aim of the study was to evaluate the incidence of cross-infections with P. aeruginosa in children with CF.. CF patients from whom at least one P. aeruginosa strain had been isolated were included in the study. The strain genotyping was performed using pulse-field gel electrophoresis. The history of contacts between patients was established based on questionnaires.. The study group consisted of 75 patients (aged 1.0-19.2 years) and the material included 170 P. aeruginosa strains. Cross-infections occurred in a group of 26 patients. In this group, the risk of the predicted occurrence of forced expiratory volume in 1 second ≤ 70% was five times greater and the risk of longer cumulative hospitalization time for intravenous antibiotic therapy (>14 days/year) was almost five times greater. In the clonal groups of strains, the multidrug-resistance rate was significantly higher than in other groups. In 2011, all tested strains were susceptible to colistin, whereas in 2012, three strains from the largest clonal group showed high levels of resistance to colistin.. Cross-infections with P. aeruginosa occurred in our group of patients and were associated with poor clinical outcomes. Antimicrobial resistance rate in the strains isolated from such infections was significantly higher, and this included three strains resistant to colistin.

Topics: Adolescent; Adult; Anti-Bacterial Agents; Child; Child, Preschool; Colistin; Cross Infection; Cystic Fibrosis; Drug Resistance, Microbial; Female; Forced Expiratory Volume; Genotype; Humans; Incidence; Infant; Male; Pseudomonas aeruginosa; Pseudomonas Infections; Treatment Outcome; Young Adult

Colistin and carbapenem-resistant Acinetobacter calcoaceticus- Acinetobacter baumannii complex (CCR-Acb complex) was isolated from two consecutive patients in the neurological intensive care unit (NICU). An urgent reaction to this desperate situation was required.. Screening cultures were taken from the other patients sharing the NICU with index patients and repeated periodically. NICU was closed for new admissions. Infection control precautions (ICP) such as hand hygiene, cohorting patients colonized with CCR-Acb complex, cohorting the staff caring for these patients, daily bathing with chlorhexidine gluconate impregnated clothes, using gowns when contacting with patients and patient care area, and sodium hypochlorite tablets for environmental cleaning were enforced.. Screening cultures revealed carbapenem-resistant Acb complex in 12 out of 32 patients and 8 of them were colonized with CCR-Acb complex. NICU was opened for new admissions one month later. No further new cases with CCR-Acb complex were detected by screening cultures after 6 weeks with enforcement of ICP. Moreover, the rate of nosocomial infections caused by other multi-drug resistant Gram-negative bacilli (MDR-GNB) decreased significantly when rates before and after closing the NICU were compared.. ICP were effective not only to limit the spread of CCR-Acb complex but also decreased the incidence of other MDR-GNB infections when applied adequately.

Topics: Acinetobacter baumannii; Acinetobacter calcoaceticus; Acinetobacter Infections; Aged; Carbapenems; Colistin; Cross Infection; Disease Outbreaks; Drug Resistance, Multiple, Bacterial; Female; Humans; Intensive Care Units; Male; Microbial Sensitivity Tests

We present an updated picture (1/1/2017-31/08/2019) of the frequency of carbapenemase producing Klebsiella pneumoniae (CPKP) in surveillance rectal swabs (SRS) and in clinical samples (CS) of patients admitted to a tertiary level hospital, focusing on longitudinal evolution of CPKP detected in SRS and on colistin resistant strains.. Retrospective longitudinal analysis. Only the first positive CPKP strain isolated from each patient was included.. 638 CPKP strains were identified (471 in SRS and 167 in CS). SRS frequency increased over time in the medical department, remained high in the surgical department (SD) and decreased in the intensive care department. Most SRS-71.3%-and 49.1% of CS had nosocomial origin; about half of the SRS were identified in the SD. Regarding SRS evolution, carriage was confirmed in 39.5% of patients, no more testing in 25.5%, clinical involvement in 24.8 %, and negative result in 10.2%. Rates of colistin resistance were 20.1% in 2017, 31.2% in 2018 and 26.9% in 2019.. CPKP diffusion is still an important issue despite the surveillance program. It is vital to enhance medical staff's awareness on this because most CPKP first detections in SRS occurred during hospital stay due to a nosocomial acquisition with a comparable picture over time. Colistin resistance is increasing.

Topics: Adult; Aged; Aged, 80 and over; Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; Colistin; Cross Infection; Drug Resistance, Bacterial; Epidemiological Monitoring; Female; Hospitals, Teaching; Humans; Italy; Klebsiella Infections; Klebsiella pneumoniae; Longitudinal Studies; Male; Middle Aged; Rectum; Retrospective Studies; Tertiary Care Centers

Colistin is a last-resort antibiotic for the treatment of infections caused by multidrug and carbapenem-resistant Gram-negative bacteria. Colistin resistance has been emerging and multiple outbreaks have been reported in Europe and elsewhere. It has been most frequently reported in carbapenem-resistant K. pneumoniae. In this study, 24 multidrug and colistin-resistant clinical isolates (14 K. pneumoniae, one E. aerogenes, one E. cloacae, and eight A. baumannii) were collected from four hospitals in Croatia from 2013 to 2018, in order to analyse the molecular epidemiology and mechanisms of antibiotic resistance. β-lactamase and carbapenemase genes were detected by PCR. Genotyping was done on selected isolates by rep-PCR. Whole genome sequencing (WGS) was performed to discover possible molecular mechanisms for the observed colistin resistance. All isolates, except two K. pneumoniae isolates, were extensively drug resistant. Ten out of 16 (63%) K. pneumoniae isolates possessed bla

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; Colistin; Croatia; Cross Infection; Drug Resistance, Multiple, Bacterial; Enterobacteriaceae; Enterobacteriaceae Infections; Humans; Microbial Sensitivity Tests; Phylogeny; Whole Genome Sequencing

The discovery of new antibiotics that are effective against Acinetobacter baumannii and Enterobacteralesis a research priority. Several essential oils (EOs) have displayed some antimicrobial activity and could potentially act as antibiotic adjuvants. Research in this area aims to develop new therapeutic alternatives to treat infections caused by these pathogens. MICs of different EOs were determined against A. baumannii and Klebsiella pneumoniae. Combined disk diffusion tests and checkerboard assays were used to study the synergy between the EOs and antibiotics. The fractional inhibitory concentration index (FIC

Topics: Acinetobacter baumannii; Anti-Bacterial Agents; Clove Oil; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Drug Synergism; Humans; Klebsiella pneumoniae; Microbial Sensitivity Tests; Oils, Volatile; Syzygium; Thymus Plant

Extensively drug resistant Acinetobacter baumannii (XDR-Ab), has emerged as an important pathogen in several outbreaks. The aim of our study was to investigate the eventual genetic relatedness of XDR-Ab strains recovered from burn patients and environment sites in the largest Tunisian Burn Intensive Care Unit (BICU) and to characterize β-lactamase encoding genes in these strains. Between March 04th, 2019 and April 22nd, 2019 an outbreak of XDR-Ab was suspected. Environmental screening was done. All isolates were screened by simplex PCR for β-lactamase genes. Genetic relatedness was determined by pulsed field gel electrophoresis (PFGE) of ApaI-digested total DNA. During the study period, 21 strains of A. baumannii were isolated in burn patients, mainly in blood culture (n = 7) and central vascular catheter (n = 6). All strains were susceptible to colistin but resistant to imipenem (n = 23), ciprofloxacin (n = 23), amikacin (n = 22), tigecyclin (n = 5) and rifampicin (n = 4). The blaOXA-51-like, blaOXA23, and blaADC genes were present in all strains. These resistance determinants were associated with blaPER-1 in 10 strains. The ISAba1 was inserted upstream of blaOXA-23 in all isolates. PFGE revealed two major clusters A (n = 11) and B (n = 5). This is the first description in Tunisia of clonally related PER-1 producing XDR-Ab in burn patients with probable environmental origin.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; Burn Units; Colistin; Cross Infection; Disease Outbreaks; Drug Resistance, Multiple, Bacterial; Genes, Bacterial; Humans; Tunisia

Pseudomonas aeruginosa is a major bacterial pathogen responsible for hospital-acquired infections. Although its epidemiology is considered as non-clonal, certain international high-risk multidrug-resistant clones have been recognized.. From the first report of an intra-hospital outbreak due to an SHV2a-producing P. aeruginosa strain, to describe the emergence of a new ST235-specific lineage harbouring this rare extended-spectrum β-lactamase (ESBL).. Between May and October 2018, four patients hospitalized in the cardiovascular intensive care unit of a French teaching hospital were infected by a multidrug-resistant P. aeruginosa isolate. Serotype and antimicrobial susceptibility were tested; multi-locus sequence type (MLST), core genome MLST, and resistome were determined through whole genome sequencing. A phylogenetic analysis based on single nucleotide polymorphism was performed using available ST235 genomes.. The four strains were susceptible to colistin, ciprofloxacin, ceftazidime-avibactam, and ceftolozane-tazobactam. bla. Among the ST235 P. aeruginosa strains, a sub-lineage sharing a common genetic background and harbouring the bla

Topics: Anti-Bacterial Agents; Azabicyclo Compounds; Bacterial Proteins; beta-Lactamases; Ceftazidime; Cephalosporins; Ciprofloxacin; Colistin; Cross Infection; Disease Outbreaks; Drug Combinations; Drug Resistance, Multiple, Bacterial; Female; France; Humans; Microbial Sensitivity Tests; Multilocus Sequence Typing; Polymorphism, Single Nucleotide; Pseudomonas aeruginosa; Pseudomonas Infections; Tazobactam

Klebsiella pneumoniae is an important human pathogen, able to accumulate and disseminate a variety of antimicrobial resistance genes. Resistance to colistin, one of the last therapeutic options for multi-drug-resistant bacteria, has been reported increasingly. Colistin-resistant K. pneumoniae (ColRKp) emerged in two hospitals in Rio de Janeiro state, Brazil in 2016. The aim of this study was to investigate if these ColRKp isolates were clonally related when compared between hospitals, to identify the molecular mechanisms of colistin resistance, and to describe other antimicrobial resistance genes carried by isolates. Twenty-three isolates were successively recovered, and the whole-genome sequence was analysed for 10, each of a different pulsed-field gel electrophoresis (PFGE) type. Although some PFGE clusters were found, none of them included isolates from both hospitals. Half of the isolates were assigned to CC258, three to ST152 and two to ST15. One isolate was pandrug resistant, one was extensively drug resistant, and the others were multi-drug resistant. Colistin resistance was related to mutations in mgrB, pmrB, phoQ and crrB. Eleven new mutations were found in these genes, including two nucleotide deletions in mgrB. All isolates were carbapenem resistant, and seven were associated with carbapenemase carriage (bla

Topics: Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; Brazil; Carbapenems; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Electrophoresis, Gel, Pulsed-Field; Humans; Klebsiella Infections; Klebsiella pneumoniae; Membrane Proteins; Microbial Sensitivity Tests; Transcription Factors; Whole Genome Sequencing

Resistance to colistin, a last resort antibiotic, has emerged in India. We investigated colistin-resistant Klebsiella pneumoniae(ColR-KP) in a hospital in India to describe infections, characterize resistance of isolates, compare concordance of detection methods, and identify transmission events.. Retrospective observational study.. Case-patients were defined as individuals from whom ColR-KP was isolated from a clinical specimen between January 2016 and October 2017. Isolates resistant to colistin by Vitek 2 were confirmed by broth microdilution (BMD). Isolates underwent colistin susceptibility testing by disk diffusion and whole-genome sequencing. Medical records were reviewed.. Of 846 K. pneumoniae isolates, 34 (4%) were colistin resistant. In total, 22 case-patients were identified. Most (90%) were male; their median age was 33 years. Half were transferred from another hospital; 45% died. Case-patients were admitted for a median of 14 days before detection of ColR-KP. Also, 7 case-patients (32%) received colistin before detection of ColR-KP. All isolates were resistant to carbapenems and susceptible to tigecycline. Isolates resistant to colistin by Vitek 2 were also resistant by BMD; 2 ColR-KP isolates were resistant by disk diffusion. Moreover, 8 multilocus sequence types were identified. Isolates were negative for mobile colistin resistance (mcr) genes. Based on sequencing analysis, in-hospital transmission may have occurred with 8 case-patients (38%).. Multiple infections caused by highly resistant, mcr-negative ColR-KP with substantial mortality were identified. Disk diffusion correlated poorly with Vitek 2 and BMD for detection of ColR-KP. Sequencing indicated multiple importation and in-hospital transmission events. Enhanced detection for ColR-KP may be warranted in India.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Bacterial Typing Techniques; Colistin; Cross Infection; Disk Diffusion Antimicrobial Tests; Drug Resistance, Multiple, Bacterial; Female; Humans; India; Klebsiella Infections; Klebsiella pneumoniae; Male; Middle Aged; Multilocus Sequence Typing; Retrospective Studies; Young Adult

Topics: Anti-Bacterial Agents; Colistin; Cross Infection; Economics, Pharmaceutical; Humans; Intensive Care Units; Polymyxin B

Our objective was to evaluate the in vitro activity of ceftolozane-tazobactam against multidrug resistant (MDR) and extensively drug-resistant (XDR) non metallo-β-lactamase producing Pseudomonas aeruginosa clinical isolates at Hospital Universitario Miguel Servet (Zaragoza, Spain) from February 2016 to October 2017.. We evaluated the in vitro activity of ceftolozane-tazobactam and other antipseudomonal antibiotics against 12 MDR and 117 XDR non metallo-β-lactamase producing P. aeruginosa isolates. Ceftolozane-tazobactam minimal inhibitory concentrations (MICs) were determined by MIC gradient diffusion test strip.. Among the 129 MDR/XDR isolates included, 119 (92.2%) were susceptible to ceftolozane-tazobactam, and ten (7.8%) were resistant. MIC50 was 2 mg/L, and MIC90 4 mg/L. Ceftolozane-tazobactam was the second most active antibiotic after colistin, overtaking amikacin.. Ceftolozane-tazobactam is a valuable treatment option for MDR and XDR P. aeruginosa infections in our setting.

Topics: Adult; Aged; Aged, 80 and over; Amikacin; Anti-Bacterial Agents; beta-Lactamases; Cephalosporins; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Female; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Pseudomonas aeruginosa; Pseudomonas Infections; Spain; Tazobactam

Background The emergence and rapid spread of multidrug-resistant gram-negative bacteria related to nosocomial infections is a growing worldwide problem, and polymyxins have become important due to the lack of new antibiotics. Objectives To evaluate the outcomes and pharmacoeconomic impact of using colistin and polymyxin B to treat nosocomial infections. Setting Neurosurgical, cardiovascular, or transplantation intensive care unit (ICU) at the Clinical Hospital of the University of Campinas (São Paulo, Brazil). Method A retrospective cohort study was conduct in patients in the ICU. The renal function was determined daily during treatment by measuring the serum creatinine. A cost minimization analysis was performed to compare the relative costs of treatment with colistin and polymyxin B. Main outcomes measure The outcomes were 30-day mortality and frequency and onset of nephrotoxicity after beginning treatment. Results Fifty-one patients treated with colistin and 51 with polymyxin B were included. 30-day mortality was observed in 25.49% and 33.33% of patients treated with colistin and polymyxin B, respectively; Nephrotoxicity was observed in 43.14% and 54.90% of patients in colistin and polymyxin B groups, respectively; and onset time of nephrotoxicity was 9.86 ± 13.22 days for colistin and 10.68 ± 9.93 days for polymyxin B group. Colistin treatment had a lower cost per patient compared to the cost for polymyxin B treatment (USD $13,389.37 vs. USD $13,639.16, respectively). Conclusion We found no difference between 30-day mortality and nephrotoxicity between groups; however, colistin proved to be the best option from a pharmacoeconomic point of view.

Topics: Adult; Aged; Anti-Bacterial Agents; Brazil; Cohort Studies; Colistin; Cross Infection; Drug Costs; Economics, Pharmaceutical; Female; Humans; Intensive Care Units; Male; Middle Aged; Polymyxin B; Retrospective Studies; Treatment Outcome

Multi-drug resistant Acinetobacter baumannii has emerged as important nosocomial pathogen associated with various infections including lower respiratory tract. Limited therapeutic options contribute to increased morbidity and mortality. Acinetobacter baumannii has the ability to persist in the environment for prolonged periods. Breach in infection control practices increases the chances of cross transmission between patients and inter/intraspecies transmission of resistance elements. The present prospective work was conducted among patients with lower respiratory tract infections (LRTI) in the intensive care unit (ICU) to study the etiology with special reference to Acinetobacter baumannii and the role of immediate patient environment in the ICU as possible source of infection. Acinetobacter baumannii were characterized for antimicrobial susceptibility, mechanism of carbapenem resistance and virulence determinants. Molecular typing of the clinical and environmental isolates was undertaken to study the probable modes of transmission.. Appropriate respiratory samples from 107 patients with LRTI admitted to ICU during September 2016 to March 2017 were studied for likely bacterial pathogens. Environmental samples (n = 71) were also screened. All the samples were processed using conventional microbiological methods. Consecutive Acinetobacter spp. isolated from clinical and environmental (health care workers and environment from ICU) samples were included in the study. Antimicrobial susceptibility was performed as per CLSI guidelines. Carbapenem resistance, mediated by carbapenemase genes (bla. Carbapenem resistant Acinetobacter baumannii (CRAB) is an important cause of LRTI in the ICU. PFGE suggests spread of carbapenem resistant isolates via cross transmission among patients and the environment. The detection of bla

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; Biofilms; Carbapenem-Resistant Enterobacteriaceae; Carbapenems; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Gene Transfer, Horizontal; Genes, Bacterial; Genotype; Hospitals; Humans; India; Intensive Care Units; Microbial Sensitivity Tests; Microbiological Techniques; Molecular Typing; Phenotype; Prevalence; Prospective Studies; Respiratory Tract Infections; Species Specificity; Virulence

BACKGROUND We investigated the factors affecting antibiotic resistance in the intensive care unit (ICU)-related hospital-acquired infections caused by Klebsiella pneumoniae (KP-HAI) and the effects of antibiotics used for high-level antibiotic resistance on patient survival. MATERIAL AND METHODS This retrospective study was performed at the adult ICU of Bezmialem Vakif University Hospital. Patients who were followed up between 01 January 2012 and 31 May 2017 were evaluated. Each KP strain was categorized according to resistance patterns and analyzed. The efficiency of antibiotic therapy for highly-resistant KP-HAI was determined by patients' lifespans. RESULTS We evaluated 208 patients. With the prior use of carbapenem, antibiotics against resistant Gram-positives, and tigecycline, it was observed that the resistance rate of the infectious agents had a significant increase. As the resistance category increases, a significant decrease was seen in the survival time. We observed that if the treatment combination included trimethoprim-sulfamethoxazole, the survival time became significantly longer, and tigecycline-carbapenem-colistin and tigecycline-carbapenem combination patients showed significantly shorter survival times. CONCLUSIONS When the resistance increases, delays will occur in starting suitable and effective antibiotic treatment, with increased sepsis frequency and higher mortality rates. Trimethoprim-sulfamethoxazole can be an efficient alternative to extend survival time in trimethoprim-sulfamethoxazole-susceptible KP infections that have extensive drug resistance.

Topics: Adult; Aged; Anti-Bacterial Agents; Carbapenems; Colistin; Cross Infection; Drug Resistance, Bacterial; Drug Resistance, Microbial; Female; Humans; Intensive Care Units; Klebsiella Infections; Klebsiella pneumoniae; Male; Middle Aged; Pneumonia; Retrospective Studies; Risk Factors; Survival Rate; Tigecycline; Treatment Outcome; Trimethoprim, Sulfamethoxazole Drug Combination

This study reported a hospital outbreak due to an extensively drug-resistant (XDR) OXA-72-producing strain of Acinetobacter baumannii (A. baumannii).. The isolates were found to be genotypically indistinguishable by whole-genome multiple locus sequence typing, and to belong to the international clonal complex CC2. One of these isolates sequentially developed a high resistance to colistin and rifampicin under treatment, as a result of mutations in genes pmrB and rpoB, respectively. The bla. This report highlighted the need to carefully monitor the emergence of colistin and rifampicin resistance in patients treated for infections with multidrug-resistant A. baumannii.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; Colistin; Conjugation, Genetic; Cross Infection; Disease Outbreaks; DNA-Directed RNA Polymerases; Drug Resistance, Bacterial; Female; Gene Transfer, Horizontal; Genotype; Humans; Male; Molecular Typing; Mutation; Plasmids; Rifampin; Sequence Analysis, DNA; Transcription Factors

New antibiotics are urgently needed to treat multi-drug resistant infections; however, production of novel antibiotics is diminishing. Synergistic combination drug therapy to enhance the activity of available antibiotics may improve management of patients with resistant infections.. Colistin-resistant Klebsiella pneumoniae isolates were collected from inpatients in 10 Greek hospitals and used to study combination activity of colistin plus azidothymidine. Combination activity was evaluated with the sum of fractional inhibitory concentrations (ΣFIC) using the mini checkerboard broth microdilution method.. A hundred individual strains were tested. Synergistic activity was noted in 79% (79/100) of isolates and additive activity in the remaining 21% (21/100). ΣFIC. Colistin with azidothymidine exhibited promising synergistic activity against colistin-resistant Klebsiella pneumoniae isolates warranting further investigation of the combination.

Topics: Anti-Bacterial Agents; Colistin; Cross Infection; Drug Resistance, Bacterial; Drug Synergism; Greece; Hospitals; Humans; Inpatients; Klebsiella Infections; Klebsiella pneumoniae; Microbial Sensitivity Tests; Zidovudine

Topics: Colistin; Cross Infection; Drug Resistance, Bacterial; Enterobacteriaceae; Enterobacteriaceae Infections; Humans; Mass Screening; Prospective Studies; Slovenia

Multidrug-resistant (MDR) Acinetobacter baumannii infections are considered as emerging nosocomial infections particularly in patients hospitalized in intensive care units (ICUs). Therefore, reliable detection of MDR strains is crucial for management of treatment but also for epidemiological data collections. The purpose of this study was to compare antimicrobial resistance and the clonal distribution of MDR clinical and environmental A. baumannii isolates obtained from the ICUs of 10 different hospitals from five geographical regions of Turkey in the context of the demographic and clinical characteristics of the patients.. A multicenter-prospective study was conducted in 10 medical centers of Turkey over a 6 month period. A total of 164 clinical and 12 environmental MDR A. baumannii isolates were included in the study. Antimicrobial susceptibility testing was performed for amikacin (AN), ampicillin-sulbactam (SAM), ceftazidime (CAZ), ciprofloxacin (CIP), imipenem (IMP) and colistin (COL) by microdilution method and by antibiotic gradient test for tigecycline (TIG). Pulsed-field gel electrophoresis (PFGE) was performed to determine the clonal relationship between the isolates. The detection of the resistance genes, bla. The mortality rate of the 164 patients was 58.5%. The risk factors for mortality included diabetes mellitus, liv1er failure, the use of chemotherapy and previous use of quinolones. Antimicrobial resistance rates for AN, SAM, CAZ, CIP, IMP, COL and TIG were 91.8%, 99.4%, 99.4%, 100%, 99.4%, 1.2% and 1.7% respectively. Colistin showed the highest susceptibility rate. Four isolates did not grow on the culture and were excluded from the analyses. Of 172 isolates, 166 (96.5%) carried bla. Colistin is still the most effective antibiotic for A. baumannii infections. The gene bla

Topics: Acinetobacter baumannii; Acinetobacter Infections; Adult; Aged; Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; Colistin; Cross Infection; Drug Resistance, Bacterial; Female; Humans; Imipenem; Intensive Care Units; Male; Microbial Sensitivity Tests; Middle Aged; Molecular Epidemiology; Phylogeny; Prospective Studies; Turkey

The authors report on the use of combination intravenous and inhaled colistin therapy in 2 patients with major burns admitted to an American Burn Association-verified burn center during a multidrug-resistant (MDR) Acinetobacter baumannii outbreak. Both patients had documented, culture-proven MDR Acinetobacter ventilator-associated pneumonia and bacteremia leading to sepsis. Both patients were successfully extubated and subsequently discharged from hospital. In this article, the authors provide the timeline of events and treatments that were used in these 2 cases. Combination intravenous and inhaled colistin therapy may be a valuable tool against MDR Acinetobacter infections.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Administration, Inhalation; Anti-Bacterial Agents; Burn Units; Colistin; Cross Infection; Disease Outbreaks; Drug Resistance, Multiple, Bacterial; Humans; Infusions, Intravenous; Male; Middle Aged

Topics: Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; Carbapenem-Resistant Enterobacteriaceae; Colistin; Cross Infection; DNA, Bacterial; Drug Resistance, Bacterial; Enterobacteriaceae Infections; Genes, Bacterial; Humans; Limit of Detection; Molecular Typing; Multiplex Polymerase Chain Reaction; Real-Time Polymerase Chain Reaction

This article describes the emergence of resistance and predictors of fatality for 1556 cases of healthcare-associated Gram-negative bloodstream infection in 2014 and 2015. The colistin resistance rate in Klebsiella pneumoniae was 16.1%, compared with 6% in 2013. In total, 660 (42.4%) cases were fatal. The highest fatality rate was among patients with Acinetobacter baumannii bacteraemia (58%), followed by Pseudomonas aeruginosa (45%), Klebsiella pneumoniae (41%), Enterobacter cloacae (32%) and Escherichia coli (28%). On multi-variate analysis, the minimum inhibitory concentrations for carbapenems [odds ratio (OR) 1.02, 95% confidence interval (CI) 1.01-1.04; P = 0.002] and colistin (OR 1.1, 95% CI 1.03-1.17; P = 0.001) were found to be significantly associated with fatality.

Topics: Adult; Aged; Aged, 80 and over; Anti-Bacterial Agents; Bacteremia; Carbapenems; Colistin; Cross Infection; Female; Gram-Negative Bacteria; Gram-Negative Bacterial Infections; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Retrospective Studies

Topics: Aged, 80 and over; Bacterial Proteins; Clone Cells; Colistin; Contact Tracing; Cross Infection; Drug Contamination; Drug Resistance, Multiple, Bacterial; Ethanolaminephosphotransferase; Female; France; Genes, Bacterial; Hand Hygiene; Hand Sanitizers; Humans; Infectious Disease Transmission, Patient-to-Professional; Infectious Disease Transmission, Professional-to-Patient; Klebsiella Infections; Klebsiella pneumoniae; Middle Aged; R Factors

Topics: Acinetobacter baumannii; Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; Colistin; Cross Infection; Drug Resistance, Bacterial; Gram-Negative Bacterial Infections; Health Facilities; Humans; Imipenem; Klebsiella; Libya; Microbial Sensitivity Tests; Multilocus Sequence Typing

We investigated the numbers of planktonic and biofilm cells and the expression levels of genes encoding efflux pumps and biofilm-related proteins in 10 clinical isolates of multi-drug resistant Acinetobacter baumannii (MDRA) as well as in its standard strain ATCC 19606 in the presence of colistin (CST), polymyxin B (PMB), minomycin (MIN), and tigecycline (TGC) at their respective sub-MICs. The number of planktonic and biofilm cells of ATCC 19606 decreased in the presence of all aforementioned antibiotics in a dose-dependent manner. Cell number also decreased in two representative MDRA strains, R2 and R3, in the presence of MIN and TGC in a dose-dependent manner. In contrast, the number of biofilm cells in these two strains increased in the presence of CST, while they increased significantly in the presence of PMB in R2 only. Pearson correlation analysis revealed that the number of biofilm cells was positively and significantly correlated with the mRNA levels of genes encoding efflux pumps (adeB and adeG) and autoinducer synthase (abaI) in strain R2 and adeB, adeG, adeJ, poly-acetyl-glucosamine-porin (pgaA), and abaI in strain R3 in the presence of CST. It was positively and significantly correlated with the mRNA levels of genes encoding adeB in strain R2 and an outer membrane protein A (ompA) and biofilm-associated protein (bap) in strain R3 in the presence of PMB. These results provide valuable insights into the biofilm formation potency of clinical isolates of MDRA that depends on efflux pumps and biofilm-related genes and its regulation by antibiotics.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; Bacterial Outer Membrane Proteins; Bacterial Proteins; Biofilms; Colistin; Cross Infection; Dose-Response Relationship, Drug; Drug Resistance, Multiple, Bacterial; Gene Expression Regulation, Bacterial; Humans; Membrane Transport Proteins; Microbial Sensitivity Tests; Polymyxin B; RNA, Messenger

Acinetobacter baumannii is one of the antibiotic-resistant superbugs that threatens hospitalized patients. Emergence and spread of the multidrug-resistant (MDR) and extensively drug-resistant (XDR) clones cause erratic outbreaks following environmental contamination of hospital settings.. The present study intended to characterize the antimicrobial resistant profiles and the genotypes of clinical and environmental isolates of A. baumannii as a result of dissemination of resistant strains.. Clinical and environmental isolates of A. baumannii were obtained from patients, staff, and environment of an educational hospital in Tehran. Antimicrobial susceptibility testing was carried out using the disk diffusion and E-test methods. Multiplex PCR was performed for detection of OXA-type genes (bla. All the isolates were found to be susceptible to colistin and most of them (77%) were non-susceptible to tigecycline. A majority of the clinical and environmental isolates (97%) were considered as MDR strains and 41% as XDR. In multiplex detection, bla. The present study highlights the circulation of drug-resistant A. baumannii strains in different wards of hospitals principally in intensive care unit (ICU) as a nosocomial pathogen due to unwise managements.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; Carbapenems; Colistin; Communicable Diseases, Emerging; Cross Infection; Cross-Sectional Studies; Drug Resistance, Multiple, Bacterial; Genotype; Hospitals, Teaching; Humans; Intensive Care Units; Iran; Minocycline; Molecular Typing; Tigecycline

A total of 18,656 Enterobacteriaceae and 4,175 Pseudomonas aeruginosa were consecutively collected from 85 US hospitals and tested for susceptibility by broth microdilution methods in a central monitoring laboratory (JMI Laboratories). The antimicrobial susceptibility and frequency of key resistance phenotypes were assessed and stratified by infection type as follows: bloodstream (BSI; 3,434 isolates; 15.0%), pneumonia (6,439; 28.2%), skin and skin structure (SSSI; 4,134; 18.1%), intra-abdominal (IAI; 951; 4.2%), and urinary tract (UTI; 7,873; 34.5%). Ceftazidime-avibactam was active against 99.9% to 100.0% of Enterobacteriaceae and 97.0% (pneumonia) to 99.4% (UTI) of P. aeruginosa isolates. Susceptibility rates were consistently lower for β-lactams, such as ceftazidime (82.3% vs. 87.1-90.8%), piperacillin-tazobactam (87.5% vs. 90.2-95.6%), and meropenem (96.8% vs. 98.4-99.4%) among Enterobacteriaceae from pneumonia compared to other infection types. Susceptibility to gentamicin was also generally lower among isolates from pneumonia, whereas susceptibility to levofloxacin and colistin were lowest among BSI and SSSI isolates, respectively. The occurrence of multidrug-resistance (MDR; 8.2% overall), extensively drug-resistance (XDR; 1.1% overall), and carbapenem-resistant Enterobacteriaceae (CRE; 1.3% overall) phenotypes were markedly higher among isolates from patients with pneumonia compared to other infection types. Among P. aeruginosa, susceptibility rates for ceftazidime, piperacillin-tazobactam, and gentamicin were lowest among isolates from pneumonia, whereas susceptibility to meropenem was similar among isolates from BSI, pneumonia, and IAI (77.3-77.9%), and susceptibility to levofloxacin was markedly lower among UTI isolates (67.1%). The frequencies of P. aeruginosa isolates with MDR and XDR phenotypes were highest among isolates from patients with pneumonia.

Topics: Anti-Bacterial Agents; Azabicyclo Compounds; Ceftazidime; Colistin; Cross Infection; Drug Combinations; Drug Resistance, Multiple, Bacterial; Enterobacteriaceae; Enterobacteriaceae Infections; Humans; Meropenem; Microbial Sensitivity Tests; Penicillanic Acid; Piperacillin; Piperacillin, Tazobactam Drug Combination; Pseudomonas aeruginosa; Pseudomonas Infections; Thienamycins; United States

Topics: Adult; Anti-Bacterial Agents; Bacterial Adhesion; Bacterial Proteins; beta-Lactamases; Biofilms; Brazil; Colistin; Colony Count, Microbial; Cross Infection; Drug Resistance, Bacterial; Drug Resistance, Multiple, Bacterial; Humans; Klebsiella Infections; Klebsiella pneumoniae; Microbial Sensitivity Tests

Topics: Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; Carbapenem-Resistant Enterobacteriaceae; Colistin; Cross Infection; Drug Resistance, Bacterial; Greece; Humans; Klebsiella Infections; Klebsiella pneumoniae; Microbial Sensitivity Tests; Time Factors

Carbapenem resistance in. We analysed 2011-2016 data from the German Antimicrobial Resistance Surveillance (ARS) System, which contains routine data of antimicrobial susceptibility testing from voluntarily participating German laboratories.. We included 154,734 isolates from 655 hospitals in the analysis. Carbapenem non-susceptibility in. Carbapenem non-susceptibility in

Topics: Adult; Anti-Bacterial Agents; Carbapenem-Resistant Enterobacteriaceae; Carbapenems; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Female; Gentamicins; Germany; Hospitals; Humans; Intensive Care Units; Klebsiella Infections; Klebsiella pneumoniae; Male; Microbial Sensitivity Tests; Tertiary Care Centers; Tigecycline; Trimethoprim, Sulfamethoxazole Drug Combination; Young Adult

Plasmid-mediated colistin resistance driven by the mcr-1 gene is of great clinical concern. Its diffusion in the hospital environment is unknown. We detected mcr-1-driven resistance in 8.3% of Enterobacteriaceae isolates from hospital surfaces in Italy, which might represent a reservoir of threatening nosocomial pathogens.

Topics: Anti-Bacterial Agents; Bacterial Proteins; Colistin; Cross Infection; Drug Resistance, Bacterial; Enterobacteriaceae; Enterobacteriaceae Infections; Hospitals; Humans; Italy; Microbial Sensitivity Tests

Carbapenemase-producing Klebsiella pneumoniae has become a worldwide recognized cause of nosocomial infections and requires urgent public health attention. The main reason of this concern is the increasing resistance to all the last-resort antibiotics, including colistin. The ideal methodology for colistin susceptibility testing still remains undefined. However, the emergence of colistin as one of the last-option treatments requires a reliable method to determine the susceptibility profile of resistant isolates. The aim of the present study was to evaluate the impact of detecting colistin resistance in Klebsiella pneumoniae isolates using MALDI-TOF MS in clinical routine practice. For this reason, 139 isolates of K. pneumoniae were collected during 2015-2017 from patients hospitalized at Pisa University Hospital. Colonies suspected to be colistin resistant were identified using MALDI-TOF MS (Bruker Daltonik GmbH, Bremen, Germany) following a protein extraction protocol. Strains were previously wholly genome sequenced. To create a customized database entry and to generate classifying algorithm models, 1.112 mass spectra were collected. In relation to their mass signals and intensities, a two dimensional peak distribution was created. The recognition capability of the algorithm based on two manually selected mass peaks was 91,8%, while cross validation was 87,6%. The proportion of correctly classified colistin-resistant K. pneumoniae was 91% and colistin-susceptible was 73%. The emergence of colistin-resistant Gram-negative organisms has a dramatic impact on patient outcomes. Our study, based on MALDI-TOF MS technology, offers rapid preliminary results on colistin resistance profile coupled with bacteria identification.

Topics: Algorithms; Anti-Bacterial Agents; Colistin; Cross Infection; Drug Resistance, Bacterial; Humans; Klebsiella Infections; Klebsiella pneumoniae; Microbial Sensitivity Tests; Proteome; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization

The increasing trend of extensively drugresistant gram negative bacteria responsible for nosocomial infections has prompted resurgence colistin usage. Colistin-induced nephrotoxicity is a concern with disparity in the reported rates between previous studies. This study aims to evaluate colistin-induced nephrotoxicity among Malaysian population.. The medical records of ICU patients receiving colistin therapy in Hospital Serdang and Hospital Sungai Buloh from 2010 to 2012 were retrospectively reviewed. Demographics data, treatment characteristic as well as culture result and creatinine level were documented. Nephrotoxicity was determined based on RIFLE criteria.. A total of 100 patients were included. Median daily dose, cumulative dose and duration of colistin therapy were 3.0 MIU (IQR: 4, range 1-12), 17.8 MIU (IQR: 31.5, range 2-180) and seven days (IQR: 4, range 1-30). Nephrotoxicity was found in 23% of the study population. All cases were reversible but marginally associated with higher mortality. No statistical association exist between age, gender and race as well as administration routes with nephrotoxicity by univariable analysis. The association of dose and duration with nephrotoxicity was also not significant by univariable analysis. After adjustment for confounders, statistical association between the independent variables and dependent variable remains not significant.. Lower dose and shorter duration in local settings contribute to lack of association between colistin therapy and nephrotoxicity in this study. Higher dosing regimen with loading dose application has been introduced in the latest National Antibiotic Guideline. Further evaluation of colistin-induced nephrotoxicity and potential risk factors is therefore warranted.

Topics: Acute Kidney Injury; Adult; Anti-Bacterial Agents; Colistin; Cross Infection; Female; Humans; Intensive Care Units; Malaysia; Male; Middle Aged; Retrospective Studies; Risk Factors

The aim of this study was to assess the safety and efficacy of colistin use in critically ill neonates.. This was a case-control study that included newborn infants with proven or suspected nosocomial infections between January 2012 and October 2015, at two centers in Diyarbakir, Turkey. The clinical and laboratory characteristics and outcomes of patients who received colistin therapy were reviewed and compared to patients who were treated with antimicrobial agents other than colistin during the same period.. Forty-seven cases who received intravenous colistin (colistin group) and 59 control patients (control group) were included. There were no significant differences between the groups regarding outcomes and nephrotoxicity, including acute renal failure. Colistin therapy was associated with significantly reduced serum magnesium (1.38 ± 0.39 mg/dL vs. 1.96 ± 0.39 mg/dL, p < 0.001) and hypokalemia (46.8% vs. 25.4%, p = 0.026). The patients who received colistin also had longer hospital stays (43 (32-70) days vs. 39 (28-55) days, p = 0.047), a higher rate of previous carbapenem exposure (40.4% vs. 11.9%, p = 0.001), and a higher age at the onset of infection (13 (10-21) days vs. 11 (9-15) days, p = 0.03).. This study showed that colistin was both effective and safe for treating neonatal infections caused by multidrug-resistant gram-negative bacteria. However, intravenous colistin use was significantly associated with hypomagnesemia and hypokalemia.

Topics: Acute Kidney Injury; Anti-Bacterial Agents; Case-Control Studies; Colistin; Critical Illness; Cross Infection; Drug Resistance, Multiple, Bacterial; Female; Humans; Infant, Newborn; Male

Ventilator associated pneumonia (VAP) is one of the most serious nosocomial infections in Intensive Care Unit (ICU). The aim of this study was to evaluate a new approach to spare the carbapenems for the management of patients diagnosed with VAP due to Acinetobacter baumannii (A. baumannii).. This retrospective study was conducted on VAP patients presenting for treatment at tertiary care centre between May 2014 and March 2016. The case sheets of patients who have been treated for VAP with meropenem, antibiotic adjuvant entity (AAE) and colistin were analysed.. Out of 113 patients analysed, 24 (21.3%) patients were having VAP due to MDR A. baumannii. Microbial sensitivity has shown that 87.5% of patients were sensitive to AAE and colistin whereas all of them were resistant to meropenem, imipenem and gentamycin. The mean treatment durations were 12.4±2.1, 13.2±2.4 and 14.3±2.1days for AAE, meropenem+colistin and AAE+colistin treatment groups. In AAE susceptible patients, the mean treatment duration and cost could be reduced by 23-24% and 43-53% if AAE is used empirically. In AAE-resistant patients, the mean treatment duration and cost could be reduced by 21% and 26% if AAE+colistin regime is used empirically instead of meropenem followed by AAE+colistin.. Clinical assessment with microbial eradication and pharmaco-economic evaluation clearly shows benefits in using AAE empirically in the management of A. baumannii infected VAP cases.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Adult; Aged; Anti-Bacterial Agents; Ceftriaxone; Chemotherapy, Adjuvant; Colistin; Cross Infection; Drug Therapy, Combination; Edetic Acid; Female; Humans; Intensive Care Units; Male; Meropenem; Microbial Sensitivity Tests; Middle Aged; Pneumonia, Ventilator-Associated; Retrospective Studies; Sulbactam; Thienamycins

To assess risk factors for recurrent carbapenem-resistant Klebsiella pneumoniae bloodstream-infection (CR-KP BSI), we performed a prospective observational cohort study of all consecutive adult patients cured of a CR-KP BSI at our hospital over a six-year period (June 2010 to June 2016). Maximum follow-up per patient was 180 days from the index blood cultures (BCs). Recurrent CR-KP BSI was defined as new evidence of positive BCs in patients with documented clinical response after completing a course of anti-CR-KP therapy. Univariate and multivariate cause-specific Cox proportional hazards analysis were performed. During the study period 249 patients were diagnosed with a CR-KP BSI, 193 were deemed as cured within 14 days after index BCs and were analysed. Recurrence occurred in 32/193 patients (16.6%) within a median of 35 (IQR 25-45) days after index BCs. All but one of the recurrences occurred within 60 days after the index BCs. Comparison of recurrent and non-recurrent cases showed significant differences for colistin use (84.4% vs. 62.2%, p = 0.01), meropenem-colistin-tigecycline regimen (43.8% vs. 24.8%, p = 0.03) and length of therapy for the index BSI episode (median 18 vs. 14 days, p = 0.004). All-cause 180-day mortality (34.4% vs. 16.1%, p = 0.02) was higher in recurrent cases. In the multivariate analysis, the only independent variable was source control as a protective factor for recurrence. Recurrence is frequent among patients cured of a CR-KP BSI and is associated with higher long-term mortality. When feasible, source control is mandatory to avoid recurrence. The role of antibiotic treatment should be further investigated in large multicentre studies.

Topics: Aged; Anti-Bacterial Agents; beta-Lactam Resistance; Colistin; Cross Infection; Female; Hospitals; Humans; Incidence; Klebsiella Infections; Klebsiella pneumoniae; Male; Meropenem; Middle Aged; Minocycline; Prospective Studies; Recurrence; Risk Factors; Sepsis; Thienamycins; Tigecycline; Time Factors

The mcr-1 was first detected on a plasmid in colistin-resistant Escherichia coli from livestock and patients in China. We described here the emergence of colistin-resistant E. coli clinical isolates harboring mcr-1 on the chromosomes in Vietnam. To our knowledge, this is the first report of hospital-acquired E. coli isolates harboring mcr-1 in a medical setting in Vietnam.

Topics: Animals; Anti-Bacterial Agents; China; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Escherichia coli; Escherichia coli Infections; Escherichia coli Proteins; Humans; Livestock; Vietnam

Colistimethate sodium (CMS) is frequently used in the treatment of nosocomial multidrug-resistant gram-negative infections. Nephrotoxicity is the most important side effect. The aim of this study is to evaluate the effect of colistin on nephrotoxicity and to assess prognosis in patients treated with CMS due to hospital-acquired pneumonia (HAP).. Patients treated with CMS for HAP due to multidrug-resistant Pseudomonas aeruginosa or Acinetobacter baumannii were included in this cohort study.. We evaluated 281 patients treated with two different brands of CMS whose administration dose is different: imported (n= 58, low dose/kg) and domestic (n= 223, high dose/kg). Nephrotoxicity developed in 175 patients (62.3%). The median age (73 vs. 66 years, p= 0.004) and mortality rates were higher (66.9% vs. 52.8%, p= 0.022) in patients having nephrotoxicity. The patients receiving high dose/kg had higher nephrotoxicity rate (67.7% vs. 41.4%, p< 0.001). The clinical, bacteriological response and mortality rates of the whole group were 52.0%, 61.0%, 61.6%, respectively. The clinical and bacteriological response rates were similar in the different dose groups. Multivariate analysis showed that nephrotoxicity was associated with domestic brand depending on use of high dose (OR= 3.97), advanced age (β= 0.29, p= 0.008), male gender (OR= 2.60), hypertension (OR= 2.50), red blood cells transfusion (OR= 2.54), absence of acute kidney injury (OR= 10.19), risk stage of RIFLE (OR= 11.9).. Nephrotoxicity is associated with the use of high dose colistin, age, gender, hypertension, red blood cells replacement and RIFLE stage. The mortality rate is higher in patients developing nephrotoxicity.

Topics: Acute Kidney Injury; Adult; Aged; Anti-Bacterial Agents; Cohort Studies; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Female; Humans; Male; Middle Aged; Pneumonia; Prognosis; Renal Insufficiency

BACKGROUND The emergence of infections related to multidrug-resistant Gram-negative bacilli (MDR-GNB) reintroduced the use of colistin, an antibiotic that was previously abandoned due to adverse effects. However, because of its limited use in neonatal intensive care units, there is very little data about the effectiveness and safety of colistin in children and newborns. In this study, which will be the largest case study in the literature, we aimed to evaluate the effectiveness and safety of colistin in full-term and preterm newborns. MATERIAL AND METHODS The study included patients admitted into 2 level 3 neonatal intensive care units between January 2013 and June 2015. The medical records of patients diagnosed with sepsis, meningitis, pneumonia, and urinary tract infection based on the diagnostic culture results and treated with colistin were analyzed retrospectively. The patients whose infections were not verified were excluded from the study. RESULTS The study included 65 patients (18 term, 47 preterm). The most frequently isolated pathogens were Klebsiella pneumoniae and Acinetobacter baumannii followed by Pseudomonas aeruginosa and Enterobacter cloacae. Mean colistin treatment time was 15±3.5 days. All patients treated with colistin were being treated with at least 1 other antibiotic. While a complete clinical response was achieved in 51 (72.3%) patients, 14 (21.5%) patients died during treatment. Four (7.7%) patients died during as a result of another infection. Three patients developed renal toxicity, another 3 patients had seizures, and apnea was observed in 3 patients. CONCLUSIONS Colistin was found to be effective and safe for treatment of MDR-GNB infections in preterms and infants with very low birth weight. Given the severity of the infection, the adverse effects of colistin were at acceptable levels.

Topics: Anti-Bacterial Agents; Cohort Studies; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Female; Gram-Negative Bacterial Infections; Humans; Infant; Infant, Newborn; Infant, Premature; Intensive Care Units, Neonatal; Male; Retrospective Studies; Treatment Outcome

Topics: Acinetobacter baumannii; Acinetobacter Infections; Adolescent; Anti-Bacterial Agents; Brain Injuries, Traumatic; Cerebrospinal Fluid Shunts; Colistin; Coma; Craniotomy; Cross Infection; Drug Resistance, Multiple, Bacterial; Humans; Male; Meningitis, Bacterial; Postoperative Complications; Tigecycline

Infection caused by carbapenem-resistant Acinetobacter baumannii (CRAB) has become a major problem in intensive care units (ICUs), with high incidence and mortality. This prospective study investigated the diagnostic value and influence of active surveillance, followed by isolation and enhanced contact precaution (IECP), on the subsequent CRAB infection and colistin use.. The study prospectively enrolled 1,115 patients who were admitted to the medical ICU of Chonnam National University Hwasun Hospital between April 2011 and November 2014. Active surveillance cultures were obtained from the throat or trachea, skin, and urine. IECP was performed beginning April 2013.. Active surveillance detected CRAB in 168 (15%) patients and CRAB infection developed in 70 (6%) patients. Endotracheal tube was independently associated with both CRAB colonization and infection, whereas IECP was inversely associated with both CRAB colonization and infection in multivariate analysis (all P values <.001). The sensitivity, specificity, and positive and negative predictive values of active surveillance for subsequent CRAB infection were 84%, 90%, 47%, and 98%, respectively. The rate of CRAB acquisition, CRAB infection, and the use of colistin were significantly lower during the IECP period compared with the control period (6.5 vs 34.1, 2.6 vs 14.7, and 19.9 vs 65.5 per 1,000 patient-days, respectively; all P <.001).. Active surveillance has good specificity and negative predictive value for subsequent CRAB infection. Active surveillance followed by IECP was inversely associated with the acquisition of CRAB and subsequent CRAB infection, and was associated with a reduction in colistin use in ICU patients.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Aged; Anti-Bacterial Agents; Carbapenems; Colistin; Cross Infection; Drug Resistance, Bacterial; Female; Humans; Intensive Care Units; Male; Microbial Sensitivity Tests; Middle Aged; Patient Isolation; Population Surveillance; Predictive Value of Tests; Prospective Studies

The emergence of colistin resistance may further contribute to treatment failure of infection caused by multidrug-resistant (MDR) Klebsiella pneumoniae. The colistin resistance rates were determined and colistin-resistant carbapenemase-producing K. pneumoniae (COL-R CP-Kp) were characterized over an 18-month period in a Greek hospital. Out of 135 carbapenemase producers, 19 isolates (14%) were categorized as resistant to colistin. Phenotypic and molecular characterization of the COL-R CP-Kp isolates revealed that all were MDR blaKPC producers and, excluding one isolate of MLST ST383, belonged to the international clonal lineage ST258. Furthermore, PCR amplification and sequencing of the mgrB locus revealed nucleotide sequences of different sizes and insertions of IS1- and IS5-like mobile elements. The majority (63%) of the COL-R blaKPC producers was recovered from patients in the intensive care unit (ICU) and clinical data indicated that all patients should have acquired these isolates in the ICU. The findings of the present study underscore a concerning evolution of colistin resistance in a setting of high K. pneumoniae carbapenemase (KPC)-Kp endemicity, such as Greece. Thus, continuous surveillance, molecular characterization, prudent use of antibiotics, and implementation of infection control measures for K. pneumoniae are urgent.

Topics: Aged; Aged, 80 and over; Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; Colistin; Cross Infection; DNA Transposable Elements; Drug Resistance, Multiple, Bacterial; Epidemiological Monitoring; Female; Gene Expression; Greece; Hospitals; Humans; Intensive Care Units; Klebsiella Infections; Klebsiella pneumoniae; Male; Membrane Proteins; Microbial Sensitivity Tests; Middle Aged; Mutagenesis, Insertional; Sequence Analysis, DNA

In the present study, our objective was to evaluate and compare the clinical and microbiological results in patients receiving systemic and systemic plus inhaled colistin therapy due to nosocomial pneumonia (NP) or ventilator associated pneumonia (VAP) caused by Acinetobacter baumannii.. A retrospective matched case-control study was performed at the ICUs at Izmir Katip Celebi University Ataturk Training and Research Hospital from January 2013 to December 2014. Eighty patients who received only systemic colistin were matched 43 patients who received systemic colistin combined with inhaled therapy.. In 97.6 % of the patients colistin was co-administered with at least one additional antibiotic. The most frequently co-administered antibiotics were carbapenems (79.7 %). The patient groups did not differ significantly in terms of the non-colistin antibiotics used for treatment (p > 0.05). Acute renal injury was observed in 53.8 % and 48.8 % of the patients who received parenteral colistin or parenteral plus inhaler colistin, respectively (p = 0.603). There were no significant differences between the groups in terms of clinical success (p = 0.974), clinical failure (p = 0.291), or recurrence (p = 0.094). Only, a significantly higher partial clinical improvement rate was observed in the systemic colistin group (p = 0.009). No significant differences between the two groups in terms of eradication (p = 0.712), persistence (p = 0.470), or recurrence (p = 0.356) rates was observed. One-month mortality rate was similar in systemic (47.5 %) and systemic plus inhaled (53.5 %) treatment groups (p = 0.526).. Our results suggest that combination of inhaled colistin with intravenous colistin had no additional therapeutic benefit in terms of clinical or microbiological outcomes.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Administration, Inhalation; Adult; Aged; Aged, 80 and over; Anti-Bacterial Agents; Case-Control Studies; Colistin; Cross Infection; Female; Humans; Intensive Care Units; Male; Middle Aged; Pneumonia, Ventilator-Associated; Retrospective Studies; Young Adult

Topics: Acinetobacter baumannii; Acinetobacter Infections; Administration, Intravenous; Adolescent; Anti-Bacterial Agents; Child; Child, Preschool; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Female; Humans; Infant; Intensive Care Units, Pediatric; Male; Treatment Outcome

At the Shaare Zedek Medical Center, we have been using colistimethate sodium (CMS) for empiric as well as pathogen-directed treatment. We present our 10-year experience.. We conducted a retrospective case-series analysis of patients admitted from 1 January 2004 through 1 May 2014 who received at least one dose of CMS. Patient characteristics analysed for all admission for which patients received CMS, included: age, number of re-admissions, admission ward, renal function, disposition and microbiology results. Overall trend in defined daily dose (DDD) for CMS and resistant isolates was analysed.. A total of 5603 admissions met inclusion criteria. Patients' mean (±SD) age was 80 ± 14 years, 1162 (48%) of the admissions were from a healthcare facility and 4367 (78%) of the admissions were to general Internal Medicine wards. The median number of hospital admissions per patient was 5, median admission and discharge creatinine (mg/dl) were 1.05 and 1.01, respectively; 2.3% of admissions required first-time dialysis. The discharge rate from the hospital was 58.4%. Excluding intrinsically CMS-resistant gram-negative organisms, bloodstream and urine isolates were 98% and 100% susceptible, respectively. CMS use (DDDs) increased during the study (p for trend = 0.04) without significant increase in incidence of multidrug-resistant organisms.. Colistimethate sodium use at our institution has increased during this 10-year period. Nevertheless, there is no increasing trend in CMS-resistant organisms, 58% of the patients were discharged alive, and we did not observe significant nephrotoxicity in patients prescribed CMS. CMS should be reserved for microbiologically confirmed extensively drug-resistant gram-negative infections.

Topics: Aged, 80 and over; Anti-Bacterial Agents; Colistin; Community-Acquired Infections; Cross Infection; Drug Resistance, Bacterial; Female; Gram-Negative Bacterial Infections; Hospitalization; Humans; Male; Microbial Sensitivity Tests; Respiratory Tract Infections; Retrospective Studies; Urinary Tract Infections

The aim of the study was to investigate the prevalence of extended-spectrum β-lactamase (ESBL) and carbapenemase production among clinical isolates of Enterobacteriaceae recovered from Tunisian and Libyan hospitals.. Bacterial isolates were recovered from patients in intensive care units and identified by biochemical tests and MALDI-TOF. Antibiotic susceptibility testing was performed by disk diffusion and the E-test method. ESBL and carbapenemase activities were detected using standard microbiological tests. Antibiotic resistance-encoding genes were screened by PCR and sequencing. Clonal relationships between Klebsiella pneumoniae strains were carried out using multi-locus sequence typing (MLST).. A total of 87 isolates were characterized, with 51 and 36, respectively, identified as E. coli and K. pneumoniae. Overall the resistance prevalence was high for aminoglycosides (> 60%), fluoroquinolones (> 80%), and extended-spectrum cephalosporins (> 94%), and was low for imipenem (11.4%). Among this collection, 58 strains (66.6%) were ESBL producers and 10 K. pneumoniae strains (11.4%) were carbapenemase producers. The antibiotic resistance-encoding genes detected were blaCTX-M-15 (51.7%), blaTEM-1 (35.6%), several variants of blaSHV (21.8%), and blaOXA-48 (11.4%). The MLST typing of K. pneumoniae isolates revealed the presence of multiple clones and three novel sequence types. Also, close relationships between the OXA-48-producing strains from Tunisia and Libya were demonstrated.. This study is the first paper describing the emergence of carbapenemase- and ESBL-producing Enterobacteriaceae, sensitive to colistin, isolated in Tunisia and Libya. Active surveillance and testing for susceptibility to colistin should be implementing because resistance to colistin, mainly in Klebsiella, has been recently reported worldwide.

Topics: Anti-Bacterial Agents; Bacterial Typing Techniques; beta-Lactamases; Colistin; Cross Infection; Drug Resistance, Bacterial; Enterobacteriaceae Infections; Escherichia coli; Genotype; Hospitals; Humans; Intensive Care Units; Klebsiella pneumoniae; Libya; Microbial Sensitivity Tests; Multilocus Sequence Typing; Polymerase Chain Reaction; Prevalence; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Tunisia

Acinetobacter baumanni is known as a worldwide emerging nosocomial infections and it is classified as one of the six dangerous microorganisms by Diseases Society of America. Multi drug-resistant strains of A. baumannii have been reported in recent decades, which may be a result of the high use of antimicrobial agents. Colistin is the last form of treatment against this organism. The presence of pmrA and pmrB genes in A. baumannii causes the resistance of this organism against Colistin. This cross-sectional study was performed on 100 samples of A. baumannii isolated from ulcer, urinary, respiratory, blood of patients admitted to the intensive care unit of Shahid Rajai Shiraz hospital within a 12-month period. The diagnosis was performed by microscopic and biochemical testing using microgen kits. Determining Colistin resistance was carried out by Diffusion Disc, Colistin antibiotic disc of MAST- England and E-test. The analysis of genes pmrA and pmrB genes was done by PCR. 100 A. baumannii samples were diagnosed out of which using diffusion disk 94 cases were sensitive to Colistin and 6 cases were resistant to it. The E-test results in resistant samples presented an MIC equal to 64 micrograms per milliliter. The PCR results in sensitive and resistant to Colistin samples presented the existence of pmrA and pmrB genes. The results indicated the presence of pmrA and pmrB genes that are the main reason of A. baumannii resistance against the last line of treatment of this organism to Colistin.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; Bacterial Proteins; Colistin; Cross Infection; Cross-Sectional Studies; Drug Resistance, Bacterial; Iran; Microbial Sensitivity Tests; Polymerase Chain Reaction; Transcription Factors

Klebsiella pneumoniae is emerging as an important nosocomial pathogen due to its rapidly increasing multidrug resistance, which has led to a renewed interest in polymyxin antibiotics, such as colistin, as antibiotics of last resort. However, heteroresistance (i.e., the presence of a subpopulation of resistant bacteria in an otherwise susceptible culture) may hamper the effectiveness of colistin treatment in patients. In a previous study, we showed that colistin resistance among extended-spectrum-beta-lactamase (ESBL)-producing K. pneumoniae isolates emerged after the introduction of selective digestive tract decontamination (SDD) in an intensive care unit (ICU). In this study, we investigated heteroresistance to colistin among ESBL-producing K. pneumoniae isolates by using population analysis profiles (PAPs). We used whole-genome sequencing (WGS) to identify the mutations that were associated with the emergence of colistin resistance in these K. pneumoniae isolates. We found five heteroresistant subpopulations, with colistin MICs ranging from 8 to 64 mg/liter, which were derived from five clonally related, colistin-susceptible clinical isolates. WGS revealed the presence of mutations in the lpxM, mgrB, phoQ, and yciM genes in colistin-resistant K. pneumoniae isolates. In two strains, mgrB was inactivated by an IS3-like or ISKpn14 insertion sequence element. Complementation in trans with the wild-type mgrB gene resulted in these strains reverting to colistin susceptibility. The MICs for colistin-susceptible strains increased 2- to 4-fold in the presence of the mutated phoQ, lpxM, and yciM alleles. In conclusion, the present study indicates that heteroresistant K. pneumoniae subpopulations may be selected for upon exposure to colistin. Mutations in mgrB and phoQ have previously been associated with colistin resistance, but we provide experimental evidence for roles of mutations in the yciM and lpxM genes in the emergence of colistin resistance in K. pneumoniae.

Topics: Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; Colistin; Cross Infection; Disease Outbreaks; Drug Resistance, Bacterial; Genome, Bacterial; Humans; Klebsiella Infections; Klebsiella pneumoniae; Microbial Sensitivity Tests; Mutation; Phylogeny; Polymorphism, Single Nucleotide

Bacteria resistant to colistin, a last resort antibiotic reflect the pre-antibiotic era. In this study, colistin resistance carbapenem-resistant K. pneumoniae (COL

Topics: Anti-Bacterial Agents; beta-Lactamases; Carbapenems; Cluster Analysis; Colistin; Cross Infection; Drug Resistance, Bacterial; Genotype; Humans; India; Infant, Newborn; Intensive Care Units, Neonatal; Klebsiella Infections; Klebsiella pneumoniae; Molecular Typing

Topics: Anti-Bacterial Agents; beta-Lactam Resistance; beta-Lactamases; Biomarkers; Brazil; Colistin; Cross Infection; Humans; Intensive Care Units; Klebsiella Infections; Klebsiella pneumoniae; Prevalence; Retrospective Studies

Topics: Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Drug Therapy, Combination; Greece; Humans; Klebsiella Infections; Klebsiella pneumoniae; Polymerase Chain Reaction

Acinetobacter baumannii, a substantial nosocomial pathogen, has developed resistance to almost all available antimicrobial drugs. Bacteriophage therapy is a possible alternative treatment for multidrug-resistant (MDR) bacterial infections. In this study, we have successfully isolated bacteriophage active against clinical strains of A. baumannii by enrichment from hospital sewage sludge using representatives of those strains. The bacteriophage isolated against A. baumannii formed plaques against beta-lactamases producing strains of A. baumannii. The utility of bacteriophage specific for A. baumannii to resolve wound infection in uncontrolled diabetic rats was evaluated. Five groups of uncontrolled diabetic rats were used. Group I was noninfected (Control), Group II was infected with MDR A. baumannii and challenged with bacteriophage, Group III was infected with MDR A. baumannii, Group IV was infected with MDR A. baumannii and challenged with antibiotic colistin, and Group V consisted of noninfected rats and sprayed with phage (Phage control). A significant decrease in infection, period of epithelization, and wound contraction was observed in the phage-challenged group when compared with antibiotic-treated uncontrolled diabetic rats and the control group. To conclude the study, new insights are provided into the biology of the broad host range of A. baumannii phage, demonstrating that A. baumannii phage has prospects for the treatment of infections caused by the MDR A. baumannii.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Animals; Anti-Bacterial Agents; Bacteriophages; beta-Lactamases; Colistin; Cross Infection; Diabetes Mellitus, Experimental; Drug Resistance, Multiple, Bacterial; Male; Microbial Sensitivity Tests; Rats; Rats, Wistar; Wound Infection

Acinetobacter baumannii can cause serious infection in susceptible patients, but little has been published regarding risk factors for infection and outcomes in solid organ transplant (SOT) recipients.. We identified A. baumannii infection among adult SOT recipients that occurred between January 2001 and March 31, 2008 at a Chicago transplant center and evaluated characteristics of these infections and outcomes.. Thirty-three individuals developed A. baumannii infection during the study period. Seventy-nine percent had healthcare-associated infection with respiratory tract as the most common site of infection (64%). Eighty-two percent of patients had received antibiotics within two wk prior to A. baumannii infection and multidrug resistance (MDR) or extensive resistance (XDR) occurred in 85%. The median time to onset of infection was five months after transplant. The 30-d mortality was 24% and was associated with XDR. Administration of an appropriate antibiotic within three d was associated with lower 30-d mortality (OR 0.16, p = 0.047). All isolates tested against colistin were susceptible.. SOT recipients with A. baumannii infection had high mortality associated with delay in appropriate antibiotic therapy and XDR organisms. The use of colistin-containing treatment regimens should be considered in these patients when A. baumannii infection is suspected or identified in patients who have received prior antibiotics.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Adult; Aged; Anti-Bacterial Agents; Colistin; Cross Infection; Female; Humans; Immunocompromised Host; Logistic Models; Male; Middle Aged; Organ Transplantation; Postoperative Complications; Retrospective Studies; Risk Factors

The aim of this study was to investigate the prevalence and the mechanisms of carbapenem and colistin resistance in Acinetobacter baumannii clinical isolates in an Algerian hospital.. Twelve isolates were collected between October 2013 and March 2014. All isolates were resistant to almost all antibiotics tested with a high-level resistance to imipenem (minimum inhibitory concentrations [MICs] >32 mg/L) with one strain showing resistance to colistin (MIC=16 mg/L). The results of the modified Hodge test and the modified Carba NP test were positive for all isolates. Besides, the activity of β-lactamases was inhibited by EDTA in only two isolates. All the 12 isolates contained the naturally occurring blaOXA-51-like gene. Ten of them harbored the OXA β-lactamases: blaOXA-23 (six isolates) and blaOXA-24 (four isolates) genes, while two isolates were positive for blaNDM-1 gene. The colistin-resistant isolate producing OXA-24 enzyme harbored a single mutation in the pmrB gene. Multilocus sequence typing demonstrated that the 12 isolates belonged to 2 clones: 10 to ST2 and 2 to ST85.. Here, we describe the mechanisms of carbapenem resistance and we report the first colistin and carbapenemase-producing A. baumannii clinical isolate from a patient in Algeria.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Algeria; Anti-Bacterial Agents; Bacterial Proteins; Base Sequence; beta-Lactamases; Clone Cells; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Edetic Acid; Female; Gene Expression Regulation, Bacterial; Humans; Imipenem; Male; Microbial Sensitivity Tests; Molecular Sequence Data; Multilocus Sequence Typing; Mutation; Phylogeny; Plasmids; Sequence Alignment; Sequence Analysis, DNA; Transcription Factors

The aim of this study was to investigate the prevalence and characteristics of imipenem-resistant Acinetobacter baumanni isolated from surgical wards in a university hospital, China. A total of 143 non-duplicate A. baumannii were isolated from 517 inpatients in surgery intensive care units (ICUs), burn wards, and general surgery wards. Of these, 102 isolates of A. baumannii (71.3%) were resistant to imipenem. Among imipenem-resistant isolates, all isolates were resistant to almost all antimicrobial agents except polymyxin E, all isolates were positive for blaOXA-23 and blaOXA-51 in addition to ISAba1, 52 (51%) were positive for blaOXA-58, 8 (7.8%) contained blaVIM-2, which co-harbored with blaOXA-58. Molecular typing revealed the presence of three clones among imipenem-resistant isolates. This study confirmed that A. baumannii strains harboring OXA or VIM type β-lactamases are widely distributed throughout the surgery wards. The data demonstrate that there was a high prevalence of imipenem-resistant A. baumannii infection in the region.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Bacterial Proteins; beta-Lactamases; China; Colistin; Cross Infection; Drug Resistance, Multiple; Drug Resistance, Multiple, Bacterial; Hospital Units; Hospitals, University; Humans; Imipenem; Intensive Care Units; Microbial Sensitivity Tests; Molecular Typing

Biofilm formation, a virulence factor of Acinetobacter baumannii, is associated with long-term survival in hospital environments and provides resistance to antibiotics. Standard tests for antibiotic susceptibility involve analyzing bacteria in the planktonic state. However, the biofilm formation ability can influence antibiotic susceptibility. Therefore, here, the biofilm formation ability of A. baumannii clinical isolates from Korea was investigated and the susceptibility of biofilm and planktonic bacteria to colistin was compared. Of the 100 clinical isolates examined, 77% exhibited enhanced biofilm formation capacity relative to a standard A. baumannii strain (ATCC 19606). Differences between the minimal inhibitory concentrations and minimal biofilm-inhibitory concentrations of colistin were significantly greater in the group of A. baumannii that exhibited enhanced biofilm formation than the group that exhibited less ability for biofilm formation. Thus, the ability to form a biofilm may affect antibiotic susceptibility and clinical failure, even when the dose administered is in the susceptible range.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; Biofilms; Colistin; Cross Infection; Drug Resistance, Bacterial; Humans; Microbial Sensitivity Tests; Republic of Korea

This study determined the mechanisms and patterns of antimicrobial resistance among the isolates obtained from different wards of a teaching hospital in the city of Mashhad in north-east Iran. Between January 2012 and the end of June 2012, 36 isolates of Acinetobacter baumannii were collected from different wards of Ghaem Hospital. Antimicrobial susceptibility testing and epsilometer testing (E-test) were performed. The genetic resistance determinants of A, B and D classes of β-lactamases, aminoglycoside modifying enzymes (AMEs), efflux pumps and ISAba1 elements were assessed by PCR. Repetitive extragenic palindromic element (REP)-PCR was performed to find the genetic relatedness of the isolates. Colistin was the most effective antibiotic of those tested, where all isolates were susceptible. E-test results revealed high rates of resistance to imipenem, ceftazidime and ciprofloxacin. The majority of isolates (97  %) were multidrug-resistant. OXA-51, OXA-23 and tetB genes were detected in all isolates, but OXA-58, IMP and tetA were not detected. The prevalence of OXA-24, bla(TEM), bla(ADC), bla(VIM) and adeB were 64, 95, 61, 64 and 86  %, respectively. ISAba1 was found to be inserted into the 5' end of OXA-23 in 35 isolates (97  %). Of the AMEs, aadA1 (89  %) was the most prevalent, followed by aphA1 (75  %). The band patterns reproduced by REP-PCR showed that 34 out of 36 isolates belonged to one clone and two singletons were identified. The results confirmed that refractory A. baumannii isolates were widely distributed and warned the hospital infection control team to exert strict measures to control the infection. An urgent surveillance system should be implemented.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; beta-Lactamases; Colistin; Cross Infection; DNA Transposable Elements; Drug Resistance, Multiple, Bacterial; Female; Genetic Variation; Hospitals, Teaching; Humans; Iran; Male; Microbial Sensitivity Tests; Molecular Typing; Tetracycline Resistance

Immunocompromised patients, such as those with multiple myeloma on peritoneal dialysis, are particularly susceptible to the occurrence of peritonitis.. We presented a 56-year-old female patient with a 10-year history of multiple myeloma. The patient was on peritoneal dialysis since 2010. During 2012 the patient had the first episode of peritonitis that was successfully managed, but in 2013 the second episode of peritonitis occured. Analysis of dialysate culture and exit site swab revealed the presence of multiresistant Acinetobacter spp., which was susceptible only to colistin. Prompt colistin therapy was administered at the doses of 100,000 units/day during six days, which resulted in complete recovery of the patient, as well as improvement of local abdominal findings. Gram-negative bacteria (genus Acinetobacter) are common causative agents in hospital-acquired infections. Studies confirmed susceptibility of Acinetobacter to colistin, which was also the case with the presented patient. Intravenous administration of colistin resulted in a complete remission of this severe, life-threatening peritonitis.. Patients with multiple myeloma and renal failure are highly prone to severe life-threatening infections.

Topics: Acinetobacter; Anti-Bacterial Agents; Colistin; Cross Infection; Female; Humans; Immunocompromised Host; Kidney Failure, Chronic; Middle Aged; Multiple Myeloma; Peritoneal Dialysis; Peritonitis; Treatment Outcome

We describe an outbreak of Klebsiella pneumoniae carbapenemase (KPC)-producing Klebsiella pneumoniae (KPC-KP) ST258 that occurred in two institutions (a hospital and a nursing home) in the Netherlands between July and December 2013. In total, six patients were found to be positive for KPC-KP. All isolates were resistant to colistin and exhibited reduced susceptibility to gentamicin and tigecycline. In all settings, extensive environmental contamination was found. Whole genome sequencing revealed the presence of bla KPC-2 and bla SHV-12 genes, as well as the close relatedness of patient and environmental isolates. In the hospital setting, one transmission was detected, despite contact precautions. After upgrading to strict isolation, no further spread was found. After the transfer of the index patient to a nursing home in the same region, four further transmissions occurred. The outbreak in the nursing home was controlled by transferring all KPC-KP-positive residents to a separate location outside the nursing home, where a dedicated nursing team cared for patients. This outbreak illustrates that the spread of pan-resistant Enterobacteriaceae can be controlled, but may be difficult, particularly in long-term care facilities. It, therefore, poses a major threat to patient safety. Clear guidelines to control reservoirs in and outside the hospitals are urgently needed.

Topics: Aged; Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; Colistin; Cross Infection; Disease Outbreaks; Drug Resistance, Bacterial; Environmental Microbiology; Female; Genome, Bacterial; Humans; Infection Control; Klebsiella Infections; Klebsiella pneumoniae; Male; Middle Aged; Molecular Epidemiology; Netherlands; Patient Safety; Practice Guidelines as Topic; Prospective Studies; Sequence Analysis, DNA; Sequence Homology

In 2010 the Hellenic center for disease control and prevention launched the "Prokroustes" nationwide action plan to tackle the increasing rates of carbapenem resistance among gram-negative nosocomial pathogens. In the present report, data from a Greek tertiary-care hospital are presented three years after the adoption of the infection control measures. Carbapenem resistance rates have been contained for Klebsiella pneumoniae and Acinetobacter baumannii but not for Pseudomonas aeruginosa. More worryingly, in accordance with their overuse against carbapenem-resistant bacteria, resistance rates to colistin and tigecycline have risen significantly.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; Carbapenems; Colistin; Containment of Biohazards; Cross Infection; Drug Resistance, Multiple, Bacterial; Gentamicins; Greece; Humans; Klebsiella Infections; Klebsiella pneumoniae; Microbial Sensitivity Tests; Minocycline; Tertiary Care Centers; Tigecycline

We describe a large hospital outbreak (93 bloodstream infections) of colistin-resistant Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae isolates which was mirrored by increased colistin consumption. The outbreak was mostly traced to the clonal expansion of an mgrB deletion mutant of an ST512 strain that produced KPC-3.

Topics: Anti-Bacterial Agents; Bacteremia; Bacterial Proteins; beta-Lactamases; Colistin; Cross Infection; Disease Outbreaks; Drug Resistance, Bacterial; Electrophoresis, Gel, Pulsed-Field; Genotype; Humans; Klebsiella Infections; Klebsiella pneumoniae; Molecular Typing; Sequence Deletion

We report the emergence and analysis of a cluster of concurrent infections/colonisations with colistin-resistant Klebsiella pneumoniae and OXA-23 carbapenemase-producing Acinetobacter baumannii in patients who had undergone cardiac surgery. We describe the emergence of colistin-resistant K. pneumoniae harbouring blaCTX-M-15, blaSHV-11, blaOXA-1, blaTEM-1 beta-lactamases and aac(6')-Ib-cr fluoroquinolone resistance. Colistin-resistant K. pneumoniae infections (pneumonia, wound infection, urinary tract infections and bacteraemia) occurred in critically ill patients previously treated with colistin for post-surgery infections with carbapenem-resistant Pseudomonas aeruginosa and/or A. baumannii. Although the cause of death could not be directly attributed to a single pathogen, three patients co-infected/colonised with K. pneumoniae, P. aeruginosa and/or A. baumannii died, whilst a fourth patient who had a mono-microbial infection with colistin-resistant K. pneumoniae only survived. The use of mobile intubation equipment in patients that shared the same ward, the clustering of cases over a short period of time, as well as the pulsed-field gel electrophoresis (PFGE) data all suggest cross-contamination between patients, either through equipment or by staff contact transmission. This report presents the 'worst-case scenario' where concurrent infection/colonisation with pathogens exhibiting resistance to different types of last-resort antimicrobials occurred in some of the most debilitated intensive care unit (ICU) patients.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; Cardiology Service, Hospital; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Female; Humans; Intensive Care Units; Klebsiella Infections; Klebsiella pneumoniae; Male; Microbial Sensitivity Tests; Pseudomonas aeruginosa; Pseudomonas Infections; Romania

Carbapenem-resistant Acinetobacter baumannii isolates were obtained from 50 patients between July 2011 and July 2012 at the University Hospital A Coruña (NW Spain). These multidrug-resistant isolates, which belonged to a single clone, remained only susceptible to tigecycline, minocycline, and colistin and produced the carbapenem-hydrolyzing oxacillinase, OXA-23. This is the first reported outbreak of OXA-23-producing A. baumannii isolates in Spain.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Adult; Aged; Aged, 80 and over; Anti-Bacterial Agents; beta-Lactamases; Carbapenems; Clone Cells; Colistin; Cross Infection; Disease Outbreaks; Drug Resistance, Multiple, Bacterial; Female; Gene Expression; Hospitals, University; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Minocycline; Spain; Survival Analysis; Tigecycline

Colistin is active against most multidrug-resistant, aerobic Gram-negative bacteria. Because of the reported nephrotoxicity during the first years of use of colistin, there were concerns of its use in pediatrics where there was limited experience The aim of this study is to document the clinical characteristics and outcomes of use of colistin in pediatric patients at a pediatric intensive care unit in Turkey.. We reviewed the medical and laboratory records of 29 critically ill children who were treated with colistin for 38 courses between January 2011 and December 2011 at the Department of Pediatric Intensive Care Unit in Ankara University Medical School, Turkey.. The median age was 17 months (range 3-217 months). Male-to-female ratio was 1:1.37. Ventilator-associated pneumonia (21 courses) was the leading diagnosis followed by catheter-related blood stream infection (6 courses), bacteremia (4 courses), ventriculoperitoneal shunt infection, peritonitis and pneumonia (1 course). The most commonly isolated microorganisms were Acinetobacter baumanni, Pseudomonas aeruginosa, Klebsiella pneumoniae, Serratia marcescens, Stenotrophomonas maltophilia, and Enterobacter cloacae. Two colistin formulations were used. Colimycin (Kocak Farma) was used in 21 colistin treatment episodes. The median dosage of colistin in this group was 5.0 mg/kg/d (2.3-5.6 mg/kg/d). Colomycin (Forest Laboratories) was used in 17 colistin treatment episodes. The median dosage of colistin in the second group was 75,000 International Unit/kg/d (50,000-80,000 International Unit/kg/d). Thirty colistin treatment episodes (79%) had a good or partial clinical response and 8 (21%) had a poor clinical response. Of the 8 colistin treatment episodes with poor clinical response, 3 were in the Colimycin group and 5 were in the Colomycin group. Ten patients died. There was no evidence of neurotoxicity in this study. Nephrotoxicity was observed in 1 patient but was not attributed to colistin because the patient had multiorgan failure at the same time.. This study in a small cohort of patients suggests that the use of colistin in severe nosocomial infections caused by multidrug-resistant Gram-negative bacteria is well-tolerated and efficacious.

Topics: Adolescent; Anti-Bacterial Agents; Child; Child, Preschool; Colistin; Critical Illness; Cross Infection; Drug Resistance, Multiple, Bacterial; Female; Humans; Infant; Intensive Care Units, Pediatric; Male; Prospective Studies; Risk Factors; Treatment Outcome

To describe the efficacy of intravenous colistin on clinical and microbiological outcomes in preterm infants with nosocomial sepsis in neonatal intensive care unit (NICU) and define adverse events observed with this treatment.. The records of preterm infants who received colistin with or without positive cultures in the NICU were retrospectively reviewed. Patients were evaluated for response to therapy and side effects.. A total of 21 preterm infants with medians of 28 weeks (23-36) gestational age and 870 g (620-2,650) birth weight were included. The median duration and dose of colistin therapy were 9 days (3-26) and 3 mg/kg/d (2-5). Recovery rate in patients including all with/without positive culture was 81% (17/21). Microbiological clearance by colistin was 69% (9/13). The major side effect observed was acute kidney injury (19%). At least 24% of infants required electrolyte supplementation during the colistin therapy. Magnesium levels were significantly lower at the end of the colistin therapy (p < 0.001). Acute kidney injury and electrolyte disturbances including hypomagnesemia were reversible in all surviving patients.. We suggest that renal function tests and serum electrolytes should be monitored closely and replaced in case of any need during the colistin therapy in preterm infants.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Acute Kidney Injury; Administration, Intravenous; Anti-Bacterial Agents; Colistin; Cross Infection; Electrolytes; Female; Humans; Infant, Newborn; Infant, Premature; Infant, Premature, Diseases; Intensive Care, Neonatal; Magnesium; Male; Microbial Sensitivity Tests; Retrospective Studies; Sepsis; Water-Electrolyte Imbalance

Infections caused by multidrug-resistant (MDR) Acinetobacter baumannii have become an important healthcare-associated problem, particularly in intensive care units (ICUs).. To investigate the emergence of carbapenem- and colistin-resistant A. baumannii infections in two Sicilian hospitals.. From October 2008 to May 2011, a period which included two Italian Nosocomial Infections Surveillance in ICUs network (SPIN-UTI) project surveys, all carbapenem-resistant A. baumannii isolates from the ICUs of two hospitals in Catania, Italy, were prospectively collected. Minimum inhibitory concentrations (MICs) were measured by agar dilution, and phenotypic testing for metallo-β-lactamase (MBL) production was performed. Carbapenem resistance genes and their genetic elements were identified by polymerase chain reaction and sequencing. Genotypic relatedness was assessed by pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing. Patient-based surveillance was conducted using the SPIN-UTI protocol and previous antibiotic consumption was recorded.. Twenty-six carbapenem-resistant A. baumannii were identified. Imipenem and meropenem MICs ranged from 4 to >32 mg/L, and 15 isolates exhibited high-level colistin resistance (MICs >32 mg/L). PFGE demonstrated that all isolates belonged to a unique clonal type and were assigned to ST2 of the international clone II. They harboured an intrinsic blaOxA-51-like carbapenemase gene, blaOxA-82, which was flanked upstream by ISAba1.. The dissemination of clonally related isolates of carbapenem-resistant A. baumannii in two hospitals is described. Simultaneous resistance to colistin in more than half of the isolates is a problem for effective antibiotic treatment. Prior carbapenem and colistin consumption may have acted as triggering factors.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Adolescent; Adult; Aged; Anti-Bacterial Agents; Carbapenems; Colistin; Cross Infection; Disease Outbreaks; Drug Resistance, Bacterial; Electrophoresis, Gel, Pulsed-Field; Hospitals; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Multilocus Sequence Typing; Polymerase Chain Reaction; Sicily

Emergence of carbapenem-resistant Enterobacteriaceae has become a substantial global health problem. The aim of this study was to analyze carbapenem-resistant isolates of Enterobacter cloacae that have emerged for the first time in the intensive care unit (ICU) at the University Hospital Centre Split, Croatia. The strains were selected in the period between June and August 2012, according to their susceptibility patterns to carbapenems. Resistant isolates were screened for metallo-β-lactamase (MBL) production with the use of the imipenem-EDTA disk synergy test, and positive findings were confirmed by PCR. The type of VIM β-lactamase gene was determined by sequencing of PCR products. The genetic relatedness was evaluated using pulsed-field gel electrophoresis analysis. The demographic and clinical data were retrospectively analyzed from medical records. Five patients were infected and one patient was colonized with a single clone of multidrug-resistant VIM-1-producing E. cloacae susceptible only to colistin. Three cases of lower respiratory tract infections, one case of bacteremia, and one case of intra-abdominal infection were identified. All cases were hospital-acquired after prolonged stay in ICU. All patients had serious underlying diseases and received a broad-spectrum antibiotic. Four patients died and two had unimprovable medical condition at the time of discharge from the hospital. MBL-producing E. cloacae can cause fatal infection in severely ill patients. Monoclonal outbreak highlights the need for continuous surveillance and good infection control practices to prevent further spread since the antibiotic therapy options for infections caused by such strains are strongly limited.

Topics: Adult; Aged; Anti-Bacterial Agents; beta-Lactamases; Carbapenems; Clone Cells; Colistin; Critical Illness; Croatia; Cross Infection; Disease Outbreaks; Drug Resistance, Multiple, Bacterial; Electrophoresis, Gel, Pulsed-Field; Enterobacter cloacae; Enterobacteriaceae Infections; Female; Gene Expression; Hospitals, University; Humans; Intensive Care Units; Male; Microbial Sensitivity Tests; Middle Aged; Survival Analysis

Topics: Anti-Bacterial Agents; Colistin; Cross Infection; Humans

Topics: Anti-Bacterial Agents; Colistin; Cross Infection; Drug Resistance, Bacterial; Humans

Topics: Anti-Bacterial Agents; Colistin; Cross Infection; Drug Resistance, Bacterial; Humans; India; Klebsiella Infections; Klebsiella pneumoniae; Oncology Service, Hospital

Acinetobacter baumannii is one of the most important antibiotic-resistant nosocomial bacteria. We investigated changes in the clinical and molecular epidemiology of A. baumannii over a 10-year period. We compared the data from 2 prospective multicenter cohort studies in Spain, one performed in 2000 (183 patients) and one in 2010 (246 patients), which included consecutive patients infected or colonized by A. baumannii. Molecular typing was performed by repetitive extragenic palindromic polymerase chain reaction (REP-PCR), pulsed-field gel electrophoresis (PFGE), and multilocus sequence typing (MLST). The incidence density of A. baumannii colonization or infection increased significantly from 0.14 in 2000 to 0.52 in 2010 in medical services (p < 0.001). The number of non-nosocomial health care-associated cases increased from 1.2% to 14.2%, respectively (p < 0.001). Previous exposure to carbapenems increased in 2010 (16.9% in 2000 vs 27.3% in 2010, p = 0.03). The drugs most frequently used for definitive treatment of patients with infections were carbapenems in 2000 (45%) and colistin in 2010 (50.3%). There was molecular-typing evidence of an increase in the frequency of A. baumannii acquisition in non-intensive care unit wards in 2010 (7.6% in 2000 vs 19.2% in 2010, p = 0.01). By MSLT, the ST2 clonal group predominated and increased in 2010. This epidemic clonal group was more frequently resistant to imipenem and was associated with an increased risk of sepsis, although not with severe sepsis or mortality. Some significant changes were noted in the epidemiology of A. baumannii, which is increasingly affecting patients admitted to conventional wards and is also the cause of non-nosocomial health care-associated infections. Epidemic clones seem to combine antimicrobial resistance and the ability to spread, while maintaining their clinical virulence.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Aged; Anti-Bacterial Agents; Bacterial Typing Techniques; Carbapenems; Cohort Studies; Colistin; Colony Count, Microbial; Cross Infection; Drug Resistance, Bacterial; Electrophoresis, Gel, Pulsed-Field; Female; Humans; Incidence; Male; Middle Aged; Spain

Nosocomial infections and their rational antibiotic treatment represent a major challenge for the healthcare nowadays. In this context, gramnegative bacteria including Pseudomonas aeruginosa, Acinetobacter baumanii and Enterobacteriaceae spp. are etiologically important and characterized by a significant level of antibiotic resistance. To examine dynamics of the respiratory tract colonization by hospital flora, tracheal aspirates obtained at three time points from 69 children with severe craniocerebral trauma during their stay in ICU were analysed. Colonization was observed on the 4th day of the ICU stay with predomination of K. pneumoniae (45%) and A. baumanii (27-37%). P. aeruginosa was detected after the 8th day of the ICU stay with the isolation rate of 33%. Substantial proportions of P. aeruginosa (61%), A. baumanii (78%) and K. pneumoniae (25%) were resistant to carbapenems. In 65 carbapemen resistant isolates, the presence of carbapenemases was examined using PCRs. OXA-48 carbapenemase was detected in 11 out of 14 (78%) K. pneumoniae isolates. Among the A. baumanii isolates, 30/31 (97%) carried OXA-40 and 1/31 (3%) had OXA-23 carbapenemases. None of the examined A. baumanii and K. pneumoniae isolates produced metallo-betalactamases (MBL). In contrast, all 20 carbapenem resistant P. aeruginosa isolates produced a MBL, and in 12 out of 20 (60%) of theme VIM-2 was detected. Thus, gramnegative nosocomial microflora rapidly colonizes ICU patients and has a high level of resistance to antibiotics, including carbapenems.

Topics: Acinetobacter baumannii; Aminoglycosides; Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; beta-Lactams; Child; Colistin; Craniocerebral Trauma; Cross Infection; Drug Monitoring; Drug Resistance, Multiple, Bacterial; Enterobacteriaceae Infections; Gene Expression; Humans; Intensive Care Units, Pediatric; Klebsiella pneumoniae; Microbial Sensitivity Tests; Pseudomonas aeruginosa; Respiratory Tract Infections; Trachea; Trauma Severity Indices

Selective decontamination of the digestive tract (SDD) selectively eradicates aerobic Gram-negative bacteria (AGNB) by the enteral administration of oral nonabsorbable antimicrobial agents, i.e., colistin and tobramycin. We retrospectively investigated the impact of SDD, applied for 5 years as part of an infection control program for the control of an outbreak with extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae in an intensive care unit (ICU), on resistance among AGNB. Colistin MICs were determined on stored ESBL-producing K. pneumoniae isolates using the Etest. The occurrence of both tobramycin resistance among pathogens intrinsically resistant to colistin (CIR) and bacteremia caused by ESBL-producing K. pneumoniae and CIR were investigated. Of the 134 retested ESBL-producing K. pneumoniae isolates, 28 were isolated before SDD was started, and all had MICs of <1.5 mg/liter. For the remaining 106 isolated after starting SDD, MICs ranged between 0.5 and 24 mg/liter. Tobramycin-resistant CIR isolates were found sporadically before the introduction of SDD, but their prevalence increased immediately afterward. Segmented regression analysis showed a highly significant relationship between SDD and resistance to tobramycin. Five patients were identified with bacteremia caused by ESBL-producing K. pneumoniae before SDD and 9 patients thereafter. No bacteremia caused by CIR was found before SDD, but its occurrence increased to 26 after the introduction of SDD. In conclusion, colistin resistance among ESBL-producing K. pneumoniae isolates emerged rapidly after SDD. In addition, both the occurrence and the proportion of tobramycin resistance among CIR increased under the use of SDD. SDD should not be applied in outbreak settings when resistant bacteria are prevalent.

Topics: Anti-Bacterial Agents; Bacteremia; beta-Lactamases; Colistin; Cross Infection; Decontamination; Disease Outbreaks; Drug Resistance, Bacterial; Gastrointestinal Tract; Humans; Infection Control; Intensive Care Units; Klebsiella Infections; Klebsiella pneumoniae; Microbial Sensitivity Tests; Retrospective Studies; Tobramycin

Nosocomial infection due to multidrug-resistant Gram-negative pathogens in ICUs is a challenge for clinicians and microbiologists and has led to the resurgence of IV colistin use in the last decade. The aim of this study was to assess the efficacy of IV colistin in the treatment of critically ill children with multidrug-resistant Gram-negative infections.. Retrospective descriptive study conducted in the PICU of Maulana Azad Medical College and associated Chacha Nehru Bal Chikitsalaya, Delhi, India, during the period of January 2010 to December 2011.. The records of critically ill children with multidrug-resistant Gram-negative infections treated with IV colistin were reviewed.. Fifty critically ill children received IV colistin; their median age was 36 months (range: 1 mo-12 yr), with male:female ratio of 3:2. The isolated pathogens were Acinetobacter baumannii, Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, and Enterobacter cloacae. Mean duration of colistin therapy was 14.3 days (range, 7-21). A favorable clinical outcome occurred in 36 children (72%), and 14 children (28%) died due to severe sepsis with multiple-organ dysfunction syndrome. Renal toxicity occurred in five children and was associated with multiple-organ dysfunction syndrome in three and coadministration of vancomycin in two. No neurotoxic adverse effects due to colistin therapy were reported.. Our study suggests that IV colistin may have a role in the treatment of infections caused by multidrug-resistant Gram-negative bacteria in critically ill children, but further prospective and randomized control trials are needed to confirm its efficacy and safety in children.

Topics: Anti-Bacterial Agents; Child; Child, Preschool; Colistin; Critical Illness; Cross Infection; Drug Administration Schedule; Drug Resistance, Multiple, Bacterial; Female; Gram-Negative Bacterial Infections; Humans; Infant; Infusions, Intravenous; Intensive Care Units, Pediatric; Male; Retrospective Studies; Treatment Outcome

Serratia marcescens causes health care-associated infections with important morbidity and mortality. Particularly, outbreaks produced by multidrug-resistant isolates of this species, which is already naturally resistant to several antibiotics, including colistin, are usually described with high rates of fatal outcomes throughout the world. Thus, it is important to survey factors associated with increasing frequency and/or emergence of multidrug-resistant S. marcescens nosocomial infections. We report the investigation and control of an outbreak with 40% mortality due to multidrug-resistant S. marcescens infections that happened from November 2007 to April 2008 after treatment with colistin for Acinetobacter baumannii meningitis was started at hospital H1 in 2005. Since that year, the epidemiological pattern of frequently recovered species has changed, with an increase of S. marcescens and Proteus mirabilis infections in 2006 in concordance with a significant decrease of the numbers of P. aeruginosa and A. baumannii isolates. A single pulsed-field gel electrophoresis (PFGE) cluster of S. marcescens isolates was identified during the outbreak. When this cluster was compared with S. marcescens strains (n = 21) from 10 other hospitals (1997 to 2010), it was also identified in both sporadic and outbreak isolates circulating in 4 hospitals in Argentina. In132::ISCR1::blaCTX-M-2 was associated with the multidrug-resistant cluster with epidemic behavior when isolated from outbreaks. Standard infection control interventions interrupted transmission of this cluster even when treatment with colistin continued in several wards of hospital H1 until now. Optimizing use of colistin should be achieved simultaneously with improved infection control to prevent the emergence of species naturally resistant to colistin, such as S. marcescens and P. mirabilis.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Adult; Aged; Aged, 80 and over; Anti-Bacterial Agents; Argentina; Colistin; Cross Infection; Disease Outbreaks; Drug Resistance, Multiple, Bacterial; Electrophoresis, Gel, Pulsed-Field; Female; Genotype; Hospitals; Humans; Male; Meningitis, Bacterial; Middle Aged; Molecular Epidemiology; Molecular Typing; Retrospective Studies; Serratia Infections; Serratia marcescens; Young Adult

Use of colistin has re-emerged for the treatment of infections caused by multidrug-resistant (MDR) Gram-negative bacteria, but information on its pharmacokinetics and pharmacodynamics is limited, especially in critically ill patients. Recent data from pharmacokinetic/pharmacodynamic (PK/PD) population studies have suggested that this population could benefit from administration of higher than standard doses of colistimethate sodium (CMS), but the relationship between administration of incremental doses of CMS and corresponding PK/PD parameters as well as its efficacy and toxicity have not yet been investigated in a clinical setting. The objective was to study the PK/PD differences of CMS and colistin between three different CMS dosage regimens in the same critically ill patient. A critically ill patient with nosocomial pneumonia caused by a MDR Acinetobacter baumannii received incremental doses of CMS. During administration of the different CMS dosage regimens, CMS and colistin plasma concentrations were determined and PK/PD indexes were calculated. With administration of the highest CMS dose once daily (720 mg every 24h), the peak plasma concentration of CMS and colistin increased to 40.51 mg/L and 1.81 mg/L, respectively, and the AUC0-24/MIC of colistin was 184.41. This dosage regimen was efficacious, and no nephrotoxicity or neurotoxicity was observed. In conclusion, a higher and extended-interval CMS dosage made it possible to increase the exposure of CMS and colistin in a critically ill patient infected by a MDR A. baumannii and allowed a clinical and microbiological optimal response to be achieved without evidence of toxicity.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Adult; Anti-Bacterial Agents; Colistin; Critical Illness; Cross Infection; Drug Resistance, Multiple, Bacterial; Humans; Male; Microbial Sensitivity Tests; Plasma; Pneumonia, Bacterial

Topics: Aged; Analysis of Variance; Anti-Bacterial Agents; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Female; Gram-Negative Bacterial Infections; Hospitalization; Humans; Male; Middle Aged; Retrospective Studies; Risk Factors; Treatment Outcome

After a single patient was transferred to Leipzig University Hospital from a hospital in Rhodes, Greece, the hospital experienced the largest outbreak due to a KPC-2-producing Klebsiella pneumoniae (KPC-2-KP) strain thus far observed in Germany. Ninety patients hospitalised between July 2010 and October 2012 were affected. In an attempt to eliminate KPC-2-KP from their digestive tracts, 14 consecutive patients (16%) were treated with a short course (7 days) of selective digestive decontamination (SDD), employing colistin (1 million units q.i.d.) and gentamicin (80 mg q.i.d.) as oral solutions, and applying colistin/gentamicin gel (0.5 g) to the oral cavity. In a retrospective analysis, these 14 SDD patients were compared with the remaining 76 patients harbouring KPC-2-KP. KPC-2-KP carrier status was followed in all 14 SDD patients by submitting stool samples to KPC-specific PCR. The mean follow-up period was 48 days (range 12-103 days). Successful elimination of KPC-2-KP was defined as a minimum of three consecutive negative PCR test results separated by ≥48 h each. Decolonisation of KPC-2-KP was achieved in 6/14 patients (43%) after a mean of 21 days (range 12-40 days), but was also observed in 23/76 (30%) of the non-SDD controls (P = 0.102). SDD treatment resulted in the development of secondary resistance to colistin (19% increase in resistance rate) and gentamicin (45% increase) in post-treatment isolates. In the control group, no secondary resistance occurred. We conclude that the SDD protocol applied in this study was not sufficiently effective for decolonisation and was associated with resistance development.

Topics: Adult; Aged; Aged, 80 and over; Anti-Bacterial Agents; beta-Lactamases; Colistin; Cross Infection; Disease Outbreaks; Drug Resistance, Bacterial; Feces; Female; Gentamicins; Germany; Greece; Humans; Infection Control; Klebsiella Infections; Klebsiella pneumoniae; Male; Middle Aged; Retrospective Studies; Time Factors

The aim of this study was to investigate the efficacy and safety of colistin therapy in pediatric patients with severe nosocomial infections in pediatric intensive care unit.. The medical records of patients treated with colistin at a 200-bed university children hospital were reviewed.. Thirty-one patients (male/female = 22/9; median age, 3 years; range, 3 months-17 years) received forty-one courses of colistin. The average dose of colistin was 4.9 ± 0.5 mg/kg/day and average treatment duration was 19.8 ± 10.3 days. Three patients who received concomitant nephrotoxic agent with colistin developed nephrotoxicity. Colistin treatment was well tolerated in other patients, and neurotoxicity was not seen in any patient. Favourable outcome was achieved in 28 (68.3%) episodes. Twelve patients died during the colistin therapy. Six of these patients died because of primary underlying disease. The infection-related mortality rate was found 14.6% in this study.. In our study, colistin therapy was found to be acceptable treatment option for the severe pediatric nosocomial infections caused by multi-drug resistant bacteria. However, the use of concomitant nephrotoxic drugs with colistin must be avoided and renal function test should be closely monitored.

Topics: Acute Kidney Injury; Adolescent; Anti-Bacterial Agents; Bacterial Infections; Child; Child, Preschool; Colistin; Cross Infection; Female; Hospitals, University; Humans; Infant; Intensive Care Units, Pediatric; Male; Treatment Outcome

Nosocomial infection caused by carbapenem-resistant Acinetobacter baumannii is a worldwide problem and treatment options remain controversial. This study investigated the in vitro effect of various antibiotic combinations against carbapenem-resistant A. baumannii strains.. Antibiotic susceptibility of A. baumannii strains was analysed. In vitro synergistic efficacy of colistin combined with tigecycline, cefoperazone/sulbactam or piperacillin/tazobactam was tested against carbapenem-resistant A. baumannii strains. Synergy studies were performed using an eplisometer test-strip method.. Of the 50 carbapenem-resistant A. baumannii strains tested, 96% were susceptible to colistin and 64% were susceptible to tigecycline. Colistin-tigecycline, colistin-cefoperazone/sulbactam and colistin-piperacillin/tazobactam combinations were found to have synergistic effects against six (12%), two (4%), and one (2%), respectively, of the strains tested.. Colistin combined with tigecycline, cefoperazone/sulbactam or piperacillin/tazobactam revealed synergistic effects in some carbapenem-resistant A. baumannii strains. These results, together with the shortage of treatment options and the risk of developing resistance to colistin, suggest that clinicians should use colistin combined with other antibiotics or β-lactamase inhibitors when treating carbapenem-resistant A. baumannii infection.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; beta-Lactam Resistance; beta-Lactamase Inhibitors; Carbapenems; Cefoperazone; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Drug Synergism; Humans; Microbial Sensitivity Tests; Minocycline; Penicillanic Acid; Piperacillin; Piperacillin, Tazobactam Drug Combination; Sulbactam; Tigecycline

The increasing emergence of multi-drug resistant Acinetobacter baumannii strains as nosocomial pathogens lead to the use of antimicrobial combinations in the treatment of infections due to these bacteria. The aim of this study was to determine the MIC values of colistin and ampicillin/sulbactam and their in vitro synergistic activities by E-test in order to evaluate the effect of this combination against imipenem-resistant A.baumannii isolates. A total of 33 A.baumannii strains isolated from clinical specimens as etiologic agents of nosocomial infections and identified as imipenem-resistant were included in the study. Identification of the isolates was performed by conventional methods and their imipenem resistance was detected with BD Phoenix automated system (Becton Dickinson, USA). MIC values and in vitro synergistic activity of colistin and ampicillin/sulbactam combination were analyzed by E-test (AB Biodisk, Sweden) on Mueller-Hinton agar medium. Synergistic, additive, indifferent and antagonist effects of A.baumannii strains were evaluated by fractional inhibitory concentration (FIC) index. The combination was considered to be synergistic when the FIC index was ≤ 0.5, additive when it was 1- > 0.5 and antagonistic when ≥ 2. Of the 33 strains included in the study, 21 were resistant to colistin; 30 were resistant and 3 were moderately susceptible to ampicillin/sulbactam. MIC50 and MIC90 values and MIC range of A.baumannii strains for colistin were 8, 32 and 0.13-128 µg/ml; for ampicillin/sulbactam those values were 48, 256 and 12-256 µg/ml, respectively. According to the FIC indices, 15 strains showed synergistic, four additive, five indifferent and nine antagonistic activity to colistin and ampicillin/sulbactam combination. Among the 12 colistin-susceptible strains, nine showed antagonistic, two indifferent and one synergistic activity to the tested combination while among the 21 colistin-resistant strains 14 showed synergistic, four additive and three indifferent activity. As a result, the combination of colistin with ampicillin/sulbactam, demonstrated high synergistic activity in vitro. While the synergistic effect of this combination was more significant in colistin-resistant strains, antagonistic effect of colistin-susceptible strains was found to be notable. Therefore, colistin resistance should be primarily determined before using colistin and ampicillin/sulbactam combination in A.baumannii infections since this combination seemed to be more e

Topics: Acinetobacter baumannii; Acinetobacter Infections; Ampicillin; Anti-Bacterial Agents; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Drug Synergism; Humans; Imipenem; Microbial Sensitivity Tests; Sulbactam

Acinetobacter species are well-known causes of health care-associated infections. The longitudinal epidemiology of this species in the hospital setting is poorly understood. A sudden, persistent increase in multidrug-resistant (MDR) A baumannii infections occurred beginning in June 2006 at Temple University Hospital in Philadelphia. An analysis was done to describe the longitudinal molecular epidemiology of MDR A baumannii in a tertiary care hospital.. This was an epidemiologic investigation using repetitive extragenic palindromic-PCR (rep-PCR) of patients with a positive culture for MDR A baumannii admitted to the hospital between February 2006 and January 2010. MDR A baumannii were defined as susceptible only to colistin and/or tigecycline.. The incidence rate of MDR A baumannii rose from 0.36 cases per 1,000 patient-days (pre-epidemic) to 0.86 cases per 1,000 patient-days, due mainly to an increase in the surgical intensive care unit. Enhanced infection control measures were implemented, but waves of MDR A baumannii continued to be documented through routine surveillance. Of 32 strains collected in 2006-2007, a single predominant clone and 2 minor clones accounted for almost all of the cases of MDR A baumannii studied. Of 24 strains collected in 2008-2009, another clone, different from those studied in the earlier period, predominated, and was accompanied by 3 minor variants.. Following an outbreak in the surgical intensive care unit, MDR A baumannii persisted in our institution for a 3-year period despite rigorous infection control measures. An unexpected strain replacement occurred during this period, with the original predominant strain disappearing completely and new minor clones displacing the original minor clones.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; Bacterial Typing Techniques; Colistin; Cross Infection; Disease Outbreaks; Drug Resistance, Multiple, Bacterial; Hospitals; Humans; Incidence; Intensive Care Units; Longitudinal Studies; Minocycline; Philadelphia; Polymerase Chain Reaction; Tigecycline

Topics: Carbapenems; Colistin; Cross Infection; Doripenem; Drug Resistance, Bacterial; Drug Therapy, Combination; Female; Fosfomycin; Humans; Infusions, Intravenous; Male; Microbial Sensitivity Tests; Middle Aged; Pneumonia, Ventilator-Associated; Pseudomonas aeruginosa; Retrospective Studies; Time Factors

Gram-negative bacteria susceptible only to colistin (COS) are emerging causes of severe nosocomial infections, reviving interest in the use of colistin. However, consensus on the most effective way to administer colistin has not yet been reached.. All patients who had sepsis due to COS gram-negative bacteria or minimally susceptible gram-negative bacteria and received intravenous colistimethate sodium (CMS) were prospectively enrolled. The CMS dosing schedule was based on a loading dose of 9 MU and a 9-MU twice-daily fractioned maintenance dose, titrated on renal function. For each CMS course, clinical cure, bacteriological clearance, daily serum creatinine clearance, and estimated creatinine clearance were recorded.. Twenty-eight infectious episodes due to Acinetobacter baumannii (46.4%), Klebsiella pneumoniae (46.4%), and Pseudomonas aeruginosa (7.2%) were analyzed. The main types of infection were bloodstream infection (64.3%) and ventilator-associated pneumonia (35.7%). Clinical cure was observed in 23 cases (82.1%). Acute kidney injury developed during 5 treatment courses (17.8%), did not require renal replacement therapy, and subsided within 10 days from CMS discontinuation. No correlation was found between variation in serum creatinine level (from baseline to peak) and daily and cumulative doses of CMS, and between variation in serum creatinine level (from baseline to peak) and duration of CMS treatment.. Our study shows that in severe infections due to COS gram-negative bacteria, the high-dose, extended-interval CMS regimen has a high efficacy, without significant renal toxicity.

Topics: Aged; Aged, 80 and over; Anti-Bacterial Agents; Cohort Studies; Colistin; Critical Illness; Cross Infection; Female; Gram-Negative Bacterial Infections; Humans; Kidney Diseases; Male; Middle Aged; Prospective Studies; Sepsis; Treatment Outcome

Topics: Anti-Bacterial Agents; Colistin; Cross Infection; Female; Gram-Negative Bacterial Infections; Humans; Male; Sepsis

Stenotrophomonas maltophilia is acquiring increasing importance as a nosocomial pathogen.. We retrospectively studied the characteristics and outcome of patients with any type of S. maltophilia infection at the University Hospital of Heraklion, Crete, Greece, between 1/2005-12/2010. S. maltophilia antimicrobial susceptibility was tested with the agar dilution method. Prognostic factors for all-cause in-hospital mortality were assessed with multivariate logistic regression.. Sixty-eight patients (median age: 70.5 years; 64.7% males) with S. maltophilia infection, not related to cystic fibrosis, were included. The 68 patients were hospitalized in medical (29.4%), surgical (26.5%), hematology/oncology departments (23.5%), or the intensive care units (ICU; 20.6%). The most frequent infection types were respiratory tract (54.4%), bloodstream (16.2%), skin/soft tissue (10.3%), and intra-abdominal (8.8%) infection. The S. maltophilia-associated infection was polymicrobial in 33.8% of the cases. In vitro susceptibility was higher to colistin (91.2%), trimethoprim/sulfamethoxazole and netilmicin (85.3% each), and ciprofloxacin (82.4%). The empirical and the targeted treatment regimens were microbiologically appropriate for 47.3% and 63.6% of the 55 patients with data available, respectively. Most patients received targeted therapy with a combination of agents other than trimethoprim/sulfamethoxazole. The crude mortality and the mortality and the S. maltophilia infection-related mortality were 14.7% and 4.4%, respectively. ICU hospitalization was the only independent prognostic factor for mortality.. S. maltophilia infection in a general hospital can be associated with a good prognosis, except for the patients hospitalized in the ICU. Combination reigmens with fluoroquinolones, colistin, or tigecycline could be alternative treatment options to trimethoprim/sulfamethoxazole.

Topics: Aged; Ciprofloxacin; Colistin; Colony Count, Microbial; Cross Infection; Drug Resistance, Multiple, Bacterial; Female; Gram-Negative Bacterial Infections; Greece; Humans; Logistic Models; Male; Netilmicin; Retrospective Studies; Statistics, Nonparametric; Stenotrophomonas maltophilia; Treatment Outcome; Trimethoprim

Multiple transposons, integrons and carbapenemases were found in Klebsiella pneumoniae colistin-resistant isolates as well as a genomic resistance island of the AbaR type in Acinetobacter baumannii colistin-resistant isolates from different hospitals from Buenos Aires City. PFGE analysis showed a polyclonal dissemination of antimicrobial resistance mechanisms among K. pneumoniae isolates, while in A. baumannii isolates the epidemic clone 1 from South America was found. Resistance determinants associated with horizontal gene transfer are contributing to the evolution to pandrug resistance in both epidemic and sporadic clones.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; Argentina; Colistin; Cross Infection; DNA Transposable Elements; Drug Resistance, Bacterial; Epidemics; Gene Expression Regulation, Bacterial; Hospitals; Humans; Integrons; Klebsiella Infections; Klebsiella pneumoniae; South America

Nosocomial infections caused by multidrug-resistant (MDR) microorganisms are a common problem around the world, especially in Intensive Care Units. The aim of this study was to investigate the efficacy and safety of colistin therapy in paediatric patients with severe nosocomial infections caused by MDR Gram-negative bacteria. There were 87 episodes in 79 paediatric Intensive Care Unit patients in five different hospitals; each patient was treated intravenously with colistin and evaluated. Of the 79 patients, 54.4% were male and the median age was 30 months. The most commonly isolated microorganism was Acinetobacter baumannii, the most common isolation site was tracheal aspirate fluid and the most common type of infection was ventilator-associated pneumonia. The mean colistin dose in patients without renal failure was 5.4 ± 0.6 mg/kg/day, the mean therapy duration was 17.2 ± 8.4 days and the favourable outcome rate was 83.9%. Serious side effects were seen in four patient episodes (4.6%) during therapy; two patients suffered renal failure and the others had convulsive seizures. Other patients tolerated the drug well. The infection-related mortality rate was 11.5% and the probability of death within the first 9 days of treatment was 10 times higher than after the first 9 days. In conclusion, this study suggests that colistin is effective in the treatment of severe nosocomial infections caused by MDR Gram-negative bacteria and is generally well tolerated by patients, even after relatively long-term use.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Adolescent; Child; Child, Preschool; Colistin; Cross Infection; Drug Administration Schedule; Drug Evaluation; Drug Resistance, Multiple, Bacterial; Female; Humans; Infant; Intensive Care Units, Pediatric; Male; Pseudomonas aeruginosa; Pseudomonas Infections; Renal Insufficiency; Retrospective Studies; Seizures; Time Factors; Treatment Outcome

Topics: Anti-Bacterial Agents; Colistin; Cross Infection; Female; Gram-Negative Bacterial Infections; Humans; Male; Sepsis

Multidrug-resistant gram-negative non-fermenting bacilli are an important cause of nosocomial infection. Aim of this study was to analyze the prevalence and antimicrobial susceptibility of rods of the species Acinetobacter baumannii and Pseudomonas aeruginosa, belonging to multidrug-resistant alert pathogens.. 105 (70%) strains of A. baumannii and 46 (30%) strains of P. aeruginosa were isolated from 125 patients hospitalized in the Specialistic Hospital in Krakow, in the years 2008-2010. Taken into account first isolate from the patient. The condition for inclusion in the study was the resistance or reduced susceptibility to selected groups of antibiotics, such as beta-lactams, aminoglycosides and fluoroquinolones. Bacterial identification and antimicrobial susceptibility testing were performed by automated system Vitek 2 Compact (bioMerieux, Poland). All strains were tested with phenotypic method Etest MBL (AB Biodisk, Sweden) for the presence of resistance mechanism associated with the production of metallo-beta-lactamases.. Bacilli of the species A. baumannii were isolated most frequently from patients from the Department of Anesthesiology and Intensive Care (52%) and Burn Therapy Unit (25%), with clinical materials collected from the respiratory tract (51%), the wound swabs (18%), urine (11%) and blood (11%). Production of metallo-beta-lactamases was found in 24 (22.9%) strains of A. baumannii. Drugs effective against multidrug-resistant isolates of A. baumannii were colistin and amikacin. Department of anesthesiology and intensive care (59%) and unit of internal medicine (11%) were the main source of multidrug-resistant strains of P. aeruginosa. Pathogens were mainly isolated from clinical specimens collected from the respiratory tract (61%), urine (15%) and wound swabs (13%). Seven (15.2%) strains of P. aeruginosa produced the metallo-beta-lactamases. With regard to colistin and piperacillin with tazobactam was noted the highest percentage of susceptible isolates.. MDR bacteria belonging to alert pathogens are an important cause of many severe and difficult to treat infections which greatly increases the morbidity and mortality among hospitalized patients worldwide. Epidemiological studies and detection of local resistance patterns can provide useful information which can be used in the development of strategies to combat the rising tide of microbial antibiotic resistance.

Topics: Acinetobacter baumannii; Amikacin; Anesthesia Department, Hospital; Blood; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Environmental Monitoring; Epidemiological Monitoring; Humans; Incidence; Intensive Care Units; Microbial Sensitivity Tests; Poland; Pseudomonas aeruginosa; Respiratory System; Species Specificity; Urine; Wounds and Injuries

Acinetobacter baumannii is an opportunistic pathogen that is a cause of clinically significant nosocomial infections. Increasingly, clinical isolates of A. baumannii are extensively resistant to numerous antibiotics, and the use of polymyxin antibiotics against these infections is often the final treatment option. Historically, the polymyxins have been thought to kill bacteria through membrane lysis. Here, we present an alternative mechanism based on data demonstrating that polymyxins induce rapid cell death through hydroxyl radical production. Supporting this notion, we found that inhibition of radical production delays the ability of polymyxins to kill A. baumannii. Notably, we demonstrate that this mechanism of killing occurs in multidrug-resistant clinical isolates of A. baumannii and that this response is not induced in a polymyxin-resistant isolate. This study is the first to demonstrate that polymyxins induce rapid killing of A. baumannii and other Gram-negatives through hydroxyl radical production. This significantly augments our understanding of the mechanism of polymyxin action, which is critical knowledge toward the development of adjunctive therapies, particularly given the increasing necessity for treatment with these antibiotics in the clinical setting.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; Colistin; Cross Infection; Culture Media; Drug Resistance, Multiple, Bacterial; Free Radical Scavengers; Humans; Hydroxyl Radical; Microbial Sensitivity Tests; Microbial Viability; Polymyxin B

We describe polyclonal spread of colistin-resistant Klebsiella pneumoniae in an acute general hospital in Italy. Between June and December 2011, 58 colistin-resistant K. pneumoniae isolates were recovered from 28 patients admitted to different wards, but mainly in the intensive care units. All isolates were tested for drug susceptibility and the presence of beta-lactamase (bla) genes. Clonality was investigated by repetitive extragenic palindromic (rep)-PCR and multilocus sequence typing (MLST). Fifty-two isolates had minimum inhibitory concentrations (MICs) for colistin of 6-128 mg/L, carried bla(KPC3) and were attributed to sequence type ST258. The remaining six isolates were susceptible to carbapenems, exhibited MICs for colistin of 3-32 mg/L, and belonged to two different types, ST15 and ST273. Rep-PCR included all isolates in three clusters, one containing all ST258 KPC-3-producing isolates and two containing ST15 and ST273 isolates.Cross-transmission containment measures and intensification of staff and environmental hygiene could not stop the outbreak. Selective pressure and horizontal transmission probably contributed to emergence and spread of three different strains of colistin-resistant K. pneumoniae in the hospital. Strict implementation of the above measures and a wider awareness of the antimicrobial resistance threat are crucial to preserve the last therapeutic options of the multidrug-resistant Gram-negative infections.

Topics: Anti-Bacterial Agents; Bacterial Typing Techniques; beta-Lactamases; Carbapenems; Colistin; Cross Infection; Disease Outbreaks; DNA, Bacterial; Drug Resistance, Multiple, Bacterial; Hospitals, General; Humans; Intensive Care Units; Italy; Klebsiella Infections; Klebsiella pneumoniae; Microbial Sensitivity Tests; Multilocus Sequence Typing; Patients' Rooms; Polymerase Chain Reaction

The Gram-negative bacteria Klebsiella pneumoniae is a major cause of nosocomial infections, primarily among immunocompromised patients. The emergence of strains resistant to carbapenems has left few treatment options, making infection containment critical. In 2011, the U.S. National Institutes of Health Clinical Center experienced an outbreak of carbapenem-resistant K. pneumoniae that affected 18 patients, 11 of whom died. Whole-genome sequencing was performed on K. pneumoniae isolates to gain insight into why the outbreak progressed despite early implementation of infection control procedures. Integrated genomic and epidemiological analysis traced the outbreak to three independent transmissions from a single patient who was discharged 3 weeks before the next case became clinically apparent. Additional genomic comparisons provided evidence for unexpected transmission routes, with subsequent mining of epidemiological data pointing to possible explanations for these transmissions. Our analysis demonstrates that integration of genomic and epidemiological data can yield actionable insights and facilitate the control of nosocomial transmission.

Topics: Adult; Aged; Carbapenems; Colistin; Contact Tracing; Cross Infection; Disease Outbreaks; Drug Resistance, Bacterial; Female; Genome, Bacterial; Hospitals; Humans; Klebsiella Infections; Klebsiella pneumoniae; Male; Middle Aged; Molecular Sequence Data; Mutation; Polymorphism, Single Nucleotide; Sequence Analysis, DNA; United States; Young Adult

Acinetobacter baumannii is an emerging gram-negative nosocomial pathogen that rarely causes infections in orthopaedic patients. We report a case of imipenem-resistant Acinetobacter baumannii paraarticular infection of the knee occurring in a healthy patient following one ambulatory steroid injection for the treatment of quadriceps tendinopathy. The infection was reduced by early surgical debridement of infected tissues, abscess drainage, and prolonged antibiotic therapy with colistin. To our knowledge, this is the first case in the literature reporting such an infection following single steroid injection in orthopaedic patients.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Aged; Anti-Bacterial Agents; Colistin; Combined Modality Therapy; Cross Infection; Debridement; Drainage; Drug Administration Schedule; Drug Resistance, Multiple, Bacterial; Female; Humans; Imipenem; Injections, Intra-Articular; Knee Joint; Magnetic Resonance Imaging; Microbial Sensitivity Tests; Steroids; Tendinopathy; Treatment Outcome

In June 2004 an 8-year-old boy was admitted to a hospital in Thessaloniki, Greece, because of high fever, tachypnea, hypotonia, diarrhea, and tonoclonic convulsions. Phlebovirus infection was diagnosed by IgG seroconversion to Toscana virus. As IgM antibodies were not detected, it is suggested that this was an acute infection caused by a phlebovirus virus distinct from Toscana virus. Complication by a hospital-acquired Pseudomonas aeruginosa pneumonia resulted in 2 months of hospitalization. Slight ataxia was still present on discharge.

Topics: Acyclovir; Anti-Bacterial Agents; Antiviral Agents; Bunyaviridae Infections; Ceftriaxone; Child; Colistin; Cross Infection; Drug Therapy, Combination; Enzyme-Linked Immunosorbent Assay; Greece; Humans; Immunoglobulin G; Male; Meningoencephalitis; Phlebovirus; Pneumonia, Bacterial; Pseudomonas aeruginosa; Pseudomonas Infections; Treatment Outcome

The objectives of this study were to assess the determinants of empirical antibiotic choice, prescription patterns and outcomes in patients with hospital-acquired pneumonia (HAP)/ventilator-associated pneumonia (VAP) in Europe. We performed a prospective, observational cohort study in 27 intensive care units (ICUs) from nine European countries. 100 consecutive patients on mechanical ventilation for HAP, on mechanical ventilation>48 h or with VAP were enrolled per ICU. Admission category, sickness severity and Acinetobacter spp. prevalence>10% in pneumonia episodes determined antibiotic empirical choice. Trauma patients were more often prescribed non-anti-Pseudomonas cephalosporins (OR 2.68, 95% CI 1.50-4.78). Surgical patients received less aminoglycosides (OR 0.26, 95% CI 0.14-0.49). A significant correlation (p<0.01) was found between Simplified Acute Physiology Score II score and carbapenem prescription. Basal Acinetobacter spp. prevalence>10% dramatically increased the prescription of carbapenems (OR 3.5, 95% CI 2.0-6.1) and colistin (OR 115.7, 95% CI 6.9-1,930.9). Appropriate empirical antibiotics decreased ICU length of stay by 6 days (26.3±19.8 days versus 32.8±29.4 days; p=0.04). The antibiotics that were prescribed most were carbapenems, piperacillin/tazobactam and quinolones. Median (interquartile range) duration of antibiotic therapy was 9 (6-12) days. Anti-methicillin-resistant Staphylococcus aureus agents were prescribed in 38.4% of VAP episodes. Admission category, sickness severity and basal Acinetobacter prevalence>10% in pneumonia episodes were the major determinants of antibiotic choice at the bedside. Across Europe, carbapenems were the antibiotic most prescribed for HAP/VAP.

Topics: Acinetobacter Infections; Adult; Aged; Aminoglycosides; Anti-Bacterial Agents; Carbapenems; Colistin; Cross Infection; Europe; Female; Humans; Intensive Care Units; Length of Stay; Male; Middle Aged; Piperacillin; Pneumonia, Bacterial; Pneumonia, Ventilator-Associated; Quinolones; Respiration, Artificial; Severity of Illness Index; Treatment Outcome

Carbapenem-resistant Klebsiella pneumoniae has spread worldwide and throughout the United States. Colistin is used extensively to treat infections with this organism. We describe a cluster of colistin-resistant, carbapenem-resistant K. pneumoniae infection cases involving three institutions in Detroit, MI. A cluster of five cases of colistin-resistant, carbapenem-resistant K. pneumoniae was identified at Detroit Medical Center (DMC) from 27 July to 22 August 2009. Epidemiologic data were collected, and transmission opportunities were analyzed. Isolates were genotyped by using pulsed-field gel electrophoresis and repetitive extragenic palindromic PCR. Data regarding the use of colistin were obtained from pharmacy records. The index case of colistin-resistant, carbapenem-resistant K. pneumoniae was followed 20 days later by four additional cases occurring in a 6-day interval. All of the patients, at some point, had stayed at one particular institution. The mean number of opportunities for transmission between patients was 2.3 ± 0.5, and each patient had at least one opportunity for transmission with one of the other patients. Compared to 60 colistin-susceptible, carbapenem-resistant K. pneumoniae controls isolated in the previous year at DMC, case patients were significantly older (P = 0.05) and the carbapenem-resistant K. pneumoniae organisms isolated from them displayed much higher MICs to imipenem (P < 0.001). Colistin use was not enhanced in the months preceding the outbreak. Genotyping revealed two closely related clones. This report of a colistin-resistant, carbapenem-resistant K. pneumoniae outbreak is strongly linked to patient-to-patient transmission. Controlling the spread and novel emergence of bacteria with this phenotype is of paramount importance.

Topics: Aged; Aged, 80 and over; Anti-Bacterial Agents; Carbapenems; Colistin; Cross Infection; Disease Outbreaks; Drug Resistance, Multiple, Bacterial; Female; Genotype; Hospitals, University; Humans; Klebsiella Infections; Klebsiella pneumoniae; Male; Michigan; Microbial Sensitivity Tests; Polymerase Chain Reaction

Nosocomial infection due to multidrug-resistant Gram-negative pathogens in intensive care units is a challenge for clinicians and microbiologists, and has led to resurgence of parenteral colistin use in the last decade. Safety and efficacy data regarding intravenous colistin (colistimethate) use in neonates is sparse. We present our experience of efficacy and safety of colistimethate in the treatment of sepsis in critically sick term and preterm neonates.. The records of the neonates who received colistimethate in a neonatal intensive care unit of a tertiary care center from January 2009 to December 2009 were reviewed.. Eighteen critically sick neonates (10 term and 8 preterm) received 21 courses of colistimethate (dose ranging from 50,000 to 75,000 IU/kg/d) for treatment of pneumonia, blood stream infections, meningitis, and empyema thoracis. The isolated pathogens in decreasing order of frequency were Acinetobacter baumannii, Klebsiella pneumoniae, Pseudomonos aeruginosa, and Enterobacter. Mean duration of colistimethate was 13.1 days/course (range: 5-21 days). At least one other antibiotic was coadministered in all courses. A favorable clinical outcome occurred in 16 of 21 (76%) courses, 5 patients died due to severe sepsis with multiple organ dysfunction. Microbiologic clearance was documented in 17 courses. Increase in serum creatinine by > 0.5 mg/dL above baseline in 2 babies was associated with the presence of multiple organ dysfunction syndrome in both and coadministration of netilmicin in one.. Colistimethate intravenous administration appears to be safe and efficacious for multidrug-resistant Gram-negative infections in neonates, including preterm and extremely low birth weight neonates.

Topics: Acinetobacter baumannii; Anti-Bacterial Agents; Bacteremia; Colistin; Critical Care; Cross Infection; Drug Resistance, Multiple, Bacterial; Enterobacter; Female; Gram-Negative Bacterial Infections; Humans; Infant, Newborn; Infusions, Intravenous; Klebsiella pneumoniae; Male; Pseudomonas aeruginosa; Treatment Outcome

To analyze the efficacy of nebulized colistin in the microbiological eradication and clinical improvement of patients with pulmonary infection by multi-resistant Acinetobacter baumannii (MAB).. A retrospective study.. Intensive Care Unit of a Tertiary hospital.. Hospitalized patients on invasive mechanical ventilation with positive MAB cultures of the airway.. All received treatment with colistin (CL). Nosocomial pneumonia (NP) or Tracheobronchitis (TB) was determined according to routine criteria and colonization (CO) was determined in the case of a positive culture in the absence of infection criteria. Three groups of patients were defined: those treated with nebulized CL, those treated with IV CL and those treated with IV CL plus nebulized CL.. Baseline characteristics. Microbiological eradication and clinical recovery were evaluated according to routine criteria.. 83 patients were studied, 54 of whom were treated, with the following diagnoses: 15 (27.8%) with NP, 16 (29.6%) with TB and 23 patients (42.6%) with CO. Nebulized CL was used in 36 patients (66.7%): 66.7% of which for CO, 33.3% in treatment for TB and in no case of NP. In 61.1% of the patients, IV CL was used: 22.2% of which for CO, 38.9% for TB and 38.9% in NP. The combination of IV CL and nebulized CL was used in 15 patients (27.8%): 5 patients (33.3%) CO, 2 patients (13.3%) TB and 8 patients (53.3%) NP. Microbiological eradication was achieved in 32 patients (59.3%), with the following distribution: 8 (47.1%) with IV CL, 15 (83.3%) with nebulized CL and 9 patients (69.2%) with a combination of IV CL and nebulized CL. Clinical recovery was achieved in 42 patients (77.8%): 12 (80%) with IV CL, 18 (94.7%) with nebulized CL and 12 (85.7%) with a combination of nebulized and IV CL. These differences were not significant. In the group of patients with infection due to TB and NP (31 patients, 57.4%), microbiological eradication was achieved in 5 patients (100%) treated with nebulized CL and in 6 of the 9 patients (42.9%) treated with IV CL, the difference being significant (P<.05). Clinical recovery in this group was 100% (6 patients) treated with nebulized CL and 75% (9 of the 12 patients) in the IV CL group. This difference was not significant.. Our study suggests that treatment with colistin in patients with pulmonary infection with multi-resistant Acinetobacter baumannii could be more efficient if it were to be administrated solely nebulized or in combination with IV colistin rather than administered solely intravenously.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Administration, Inhalation; Adult; Aged; Bronchitis; Colistin; Critical Illness; Cross Infection; Dose-Response Relationship, Drug; Drug Evaluation; Drug Resistance, Multiple, Bacterial; Female; Gram-Negative Bacterial Infections; Humans; Injections, Intravenous; Male; Middle Aged; Nebulizers and Vaporizers; Pneumonia, Bacterial; Pneumonia, Ventilator-Associated; Retrospective Studies; Tracheitis; Tracheotomy

Multidrug-resistant Acinetobacter baumannii (MRAB) is an emerging cause of intensive care unit (ICU) outbreaks. Patients are the main reservoirs, inducing cross transmission. We describe an MRAB outbreak that occurred in the Prato Hospital ICU in June to August 2009.. The ICU consists of 2 separated 4-bed rooms (rooms A and B). The MRAB-positive patients were included in our study. During the outbreak, infection control measures were enhanced; patients and environmental screenings were performed. A 6-month follow-up was carried out.. Four of 26 patients admitted during the outbreak were MRAB positive. All patients were located in room A; no case was detected in room B either in the hospital or during the follow-up. Management included closure to new admissions, reinforcement of infection control measures, patient and environmental screenings, discharge of room B MRAB-negative patients for at least 5 days after the first case identification. All isolates were carbapenems resistant and tigecycline and colistin susceptible. All patients received tigecycline: 2 were successfully treated, 1 died because of preexisting illness, and 1 developed resistance and recovered after colistin therapy.. Enhanced infection control measures and adequate antibiotic strategy limited the outbreak. Tigecycline allowed rapid recovery. Nevertheless, resistance ensued; so colistin remained the only therapeutic option. However, pan-drug resistance has been reported.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Aged; Anti-Infective Agents; Colistin; Cross Infection; Disease Outbreaks; Drug Resistance, Multiple, Bacterial; Female; Humans; Infection Control; Intensive Care Units; Italy; Male; Middle Aged; Minocycline; Tigecycline; Treatment Outcome

Topics: Anti-Bacterial Agents; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Female; Gram-Negative Bacterial Infections; Humans; Male

Five cases of infection due to colistin-resistant, Klebsiella pneumoniae carbapenemase-producing K. pneumoniae belonging to the international epidemic clone ST258 occurred over a 4-month period. These cases likely represented both emergence of resistance and transmission of resistant organism. The colistin-resistant isolates were able to persist in the absence of selective pressure in vitro.

Topics: Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; beta-Lactams; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Epidemics; Humans; Klebsiella Infections; Klebsiella pneumoniae; Microbial Sensitivity Tests

Colistin is used as last treatment option for pneumonia associated with multidrug-resistant (MDR) Pseudomonas spp.. Literature about the best administration mode (inhalation versus parenteral treatment) is lacking.. A retrospective study of 20 intensive care patients with a pneumonia associated with MDR P. aeruginosa receiving colistin sulphomethate sodium (Colistineb®) between 2007 and 2009 was performed. A strain was considered multidrug-resistant if it was resistant to at least 6 of the following antibiotics: piperacillin-tazobactam, ceftazidime, cefepime, meropenem, aztreonam, ciprofloxacin, and amikacin. The administration mode, predicted mortality based on the SAPS3 score, SOFA score at onset of the colistin treatment, clinical and microbiological response, and mortality during the episode of the infection were analysed. The non parametric Kruskal-Wallis and Fisher's Exact test were used for statistical analysis of respectively the predicted mortality/SOFA score and mortality rate.. Six patients received colistin by inhalation only, 5 were treated only parenterally, and 9 by a combination of both administration modes. All patients received concomitant beta-lactam therapy. The mean predicted mortalities were respectively 72%, 68%, and 69% (p = 0.91). SOFA scores at the onset of the treatment were also comparable (p = 0.87). Clinical response was favorable in all patients receiving colistin by inhalation (6/6) and in 40% (2/5) of the patients receiving colistin parenterally (p = 0.06). In the patients with colistin administered both via inhalation and parenterally, clinical response was favorable in 78% of the patients (7/9) (p = 0.27 as compared to the treatment group receiving colistin only parenterally). When all patients with inhalation therapy were compared to the group without inhalation therapy, a favorable clinical response was present in respectively 87% and 40% (p = 0.06). In none of the patients, the Pseudomonas spp. was eradicated from the follow-up cultures.All patients in the parenterally treated group died. None of the patients receiving colistin by inhalation, and 3 of 9 patients of the combination group eventually died (p = 0.002 and p = 0.03 respectively as compared to the group receiving colistin only parenterally).. Aerosolized colistin could be beneficial as adjunctive treatment for the management of pneumonia due to MDR P. aeruginosa.

Topics: Administration, Inhalation; Adolescent; Adult; Aged; Aged, 80 and over; Anti-Bacterial Agents; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Female; Humans; Injections, Intravenous; Male; Middle Aged; Pneumonia, Bacterial; Pseudomonas aeruginosa; Pseudomonas Infections; Retrospective Studies; Treatment Outcome; Young Adult

In vitro activities of colistin and other drugs were tested against 221 Klebsiella pneumoniae isolates that were collected between 2006 and 2007 in nine tertiary care South Korean hospitals from patients with bacteremia. The clonality of colistin-resistant K. pneumoniae (CRKP) isolates was assessed by multilocus sequence typing (MLST). We found that 15 isolates (6.8%) were resistant to colistin. MLST showed that CRKP isolates were nonclonal, with colistin resistance in K. pneumoniae occurring independently and not by clonal spreading.

Topics: Anti-Bacterial Agents; Bacteremia; Colistin; Cross Infection; Drug Resistance, Bacterial; Humans; Klebsiella Infections; Klebsiella pneumoniae; Microbial Sensitivity Tests; Population Surveillance; Republic of Korea

The aim of the present study was to assess the efficacy and safety of colistimethate sodium therapy in multidrug-resistant nosocomial infections caused by Pseudomonas aeruginosa or Acinetobacter baumannii in neonates and children.. Pediatric patients hospitalized at the Uludag University Hospital who had nosocomial infections caused by multidrug-resistant P. aeruginosa or A. baumannii, were enrolled in the study. Colistimethate sodium at a dosage of 50-75 x 10(3) U/kg per day was given i.v. divided into three doses.. Fifteen patients received 17 courses of colistimethate sodium for the following infections: ventilator-associated pneumonia (n= 14), catheter-related sepsis (n= 1) and skin and soft-tissue infection (n= 2). The mean age of patients was 53.2 + 74.7 months (range, 8 days-15 years) and 60% were male. Mortality was 26.6%.. Colistimethate sodium appears to be safe and effective for the treatment of severe infections caused by multidrug-resistant P. aeruginosa or A. baumannii in pediatric patients.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Adolescent; Child; Child, Preschool; Colistin; Cross Infection; Dose-Response Relationship, Drug; Drug Administration Schedule; Drug Resistance, Multiple, Bacterial; Female; Follow-Up Studies; Hospitals, University; Humans; Infant; Infant, Newborn; Injections, Intravenous; Intensive Care Units, Neonatal; Intensive Care Units, Pediatric; Male; Microbial Sensitivity Tests; Prospective Studies; Pseudomonas aeruginosa; Pseudomonas Infections; Statistics, Nonparametric; Treatment Outcome; Turkey

Colistimethate sodium (CMS) was recently re-introduced into clinical practice as a last resort for the treatment of nosocomial infections caused by multiresistant bacteria. This retrospective cohort study was designed to identify predictors of acute kidney injury (AKI) associated with intravenous (i.v.) CMS treatment. From March 2007 to July 2008, 71 adult patients receiving CMS for > or = 72h were enrolled. AKI was defined using Risk, Injury, Failure, Loss and End-stage kidney disease (RIFLE) criteria according to serum creatinine. The median total dose of CMS was 54.3mg/kg (range 27.5-94.5mg/kg). AKI developed in 38 patients (53.5%). Cox regression analysis based of cumulative CMS dose (mg/kg) identified four independent predictors of AKI: male sex [hazard ratio (HR)=3.55, 95% confidence interval (CI), 1.47-8.55]; concomitant use of a calcineurin inhibitor (HR=6.74, 95% CI 2.49-18.24); hypoalbuminaemia (serum albumin level <2.0g/dL) (HR=6.29, 95% CI 2.04-19.39); and hyperbilirubinaemia (total bilirubin level >5mg/dL) (HR=3.53, 95% CI 1.17-10.71). In conclusion, AKI was a common complication of i.v. CMS treatment. Male sex, concomitant use of calcineurin inhibitors, hypoalbuminaemia and hyperbilirubinaemia were independent predictors of AKI. The effect of AKI on patient outcomes was not determined.

Topics: Aged; Anti-Bacterial Agents; Bacterial Infections; Cohort Studies; Colistin; Creatinine; Cross Infection; Female; Humans; Infusions, Intravenous; Kidney; Kidney Diseases; Male; Middle Aged; Retrospective Studies; Risk Factors

Emergence of multidrug-resistant Gram-negative nosocomial pathogens has led to resurgence of colistin use. Safety and efficacy data regarding colistin use in pediatric patients are sparse, while optimal dosage has not been defined. We present a case series of neonates and children without cystic fibrosis treated with various doses of colistin intravenously. The records of patients who received colistin in a tertiary-care hospital from January 2007 to March 2009 were reviewed. Thirteen patients (median age 5 years, range 22 days to 14 years) received 19 courses of colistin as treatment of pneumonia, central nervous system infection, bacteremia, or complicated soft tissue infection. The isolated pathogens were Acinetobacter baumannii, Enterobacter cloacae, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia. Daily dose of colistin (colistimethate) ranged between 40,000 and 225,000 IU/kg. Duration of administration ranged from 1 to 133 days. Other antimicrobials were co-administered in 18/19 courses. Increase of serum creatinine in one patient was associated with co-administration of colistin and gentamicin. Sixteen of 19 courses had a favorable outcome, and only two of the three deaths were infection-related. Colistin intravenous administration appears well tolerated even at higher than previously recommended doses and of prolonged duration.

Topics: Administration, Inhalation; Adolescent; Aerosols; Anti-Bacterial Agents; Child; Child, Preschool; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Female; Gram-Negative Bacterial Infections; Humans; Infant; Infant, Newborn; Infusions, Intravenous; Injections, Intraventricular; Male; Retrospective Studies; Treatment Outcome

Colistin has re-entered clinical use by necessity. We aimed to assess its effectiveness and safety compared with newer antibiotics.. This was a single-centre, prospective cohort study. Inclusion criteria were microbiologically documented pneumonia, urinary tract infection, surgical site infection, meningitis or bacteraemia treated appropriately with colistin versus imipenem, meropenem or ampicillin/sulbactam (comparators). All consecutive patients were included, only once, between May 2006 and July 2009. The primary outcome was 30 day mortality. Multivariable and Cox regression survival analyses were used to adjust comparisons between groups. Odds ratios (ORs) or hazard ratios (HRs) with 95% confidence intervals are reported.. Two hundred patients treated with colistin and 295 patients treated with comparators were included. Treatment with colistin was associated with older age, admission from healthcare facilities, mechanical ventilation and lower rate of early appropriate antibiotic treatment. The 30 day mortality was 39% (78/200) for colistin versus 28.8% (85/295) for comparators; unadjusted OR 1.58 (1.08-2.31). In the adjusted analysis the OR was 1.44 (0.91-2.26) overall and 1.99 (1.06-3.77) for bacteraemic patients (n = 220). At the end of follow-up, treatment with colistin was significantly associated with cumulative mortality; adjusted HR 1.27 (1.01-1.60) overall and 1.65 (1.18-2.31) among patients with bacteraemia. Nephrotoxicity at the end of treatment was more frequent with colistin; OR adjusted for other risk factors for nephrotoxicity 3.31 (1.54-7.08). Treatment with colistin was followed by increased incidence of Proteus spp. infections during a 3 month follow-up.. The need for colistin treatment is associated with poorer survival. Adjusted analyses suggest that colistin is less effective and more toxic than beta-lactam antibiotics.

Topics: Adult; Aged; Anti-Bacterial Agents; Cohort Studies; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Female; Gram-Negative Bacteria; Gram-Negative Bacterial Infections; Humans; Male; Middle Aged; Prospective Studies; Survival Analysis; Treatment Outcome

Topics: Anti-Bacterial Agents; Bacterial Infections; Colistin; Critical Illness; Cross Infection; Humans; Infusions, Intravenous; Male; Plasma; Renal Insufficiency

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; Carbapenems; Colistin; Cross Infection; Drug Resistance, Bacterial; Drug Synergism; Humans; Intensive Care Units; Meropenem; Microbial Sensitivity Tests; Minocycline; Sulbactam; Thienamycins; Tigecycline

Within the last decade, human infections caused by enterobacteria which produce the Klebsiella pneumoniae carbapenemase (KPC) became a serious therapeutic and epidemiological problem worldwide. The KPC producing strains of K. pneumoniae broadly disseminated in the USA then spread to Europe. Recently, the KPC-2 was found in Poland. In the presented study we tested 11 ertapenem resistant isolates of K. pneumoniae. The isolates were obtained from 10 patients of a regular hospital (RH) and from one patient of a palliative care hospital (PH) in Warsaw, Poland. Expression of the KPC was confirmed in all the tested isolates by the positive result of phenotypic test with boronic acid. All the isolates were also shown to harbour the bla(KPC) gene by PCR with primers targeting the core 372 bp fragment of the gene, and all but two were resistant to imipenem and meropenem as determined by the disc-diffusion method. The DNA sequence analysis of the complete bla(KPC) gene from representative isolate DM0269 revealed variant 2 of KPC (KPC-2). Tested isolates were subjected to genotyping by the PFGE with XbaI. Dendrogram based on the PFGE profiles was composed of two main branches with 82,3% of similarity. Branch A encompassed 9 isolates (93,2%), including the one from the PH-patient, while the two remaining isolates (86,5%) were located in branch B. Five isolates of the branch A were indistinguishable by the PFGE. The high genetic similarity of the branch A isolates strongly suggests the intra-hospital dissemination of epidemic K. pneumoniae KPC+ sensu stricto strain. Most probably, the strain was also transferred to the palliative care hospital. In contrast, the branch B isolates appear to belong to the distinct sensu stricto strain, that has acquired the bla(KPC) gene via horizontal transfer. This is the first report on the intra-hospital dissemination of the KPC producing K. pneumoniae in Poland. It is noteworthy, all the tested strains were also resistant to cefotaxime, ceftazidime, aztreonam, ciprofloxacin and sulphonamides, but sensitive to colistin.

Topics: Adult; Aged; Aztreonam; Bacterial Proteins; beta-Lactamases; Cefotaxime; Ceftazidime; Ciprofloxacin; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Female; Genotype; Humans; Klebsiella Infections; Klebsiella pneumoniae; Male; Middle Aged; Poland; Species Specificity

We describe a hospital outbreak caused by colistin-resistant Klebsiella pneumoniae producing KPC-2 beta-lactamase in two distinct medical centres. Seven clinical isolates of K. pneumoniae exhibiting resistance to carbapenems were collected from patients with hospital-acquired infection. All isolates were phenotypically positive for carbapenemase activity but negative for metallo-beta-lactamase production. PCR analysis using specific primers for bla(KPC), bla(SHV), bla(TEM) and bla(CTX-M) demonstrated that all clinical strains of K. pneumoniae from hospital A and one isolate from hospital B were genetically related and carried bla(KPC-2) in addition to bla(SHV-12). In contrast, the remaining isolate carried bla(S)(HV-5) with bla(K)(PC-2) and yielded a different profile. These results indicate the clonal spread of KPC producers between hospitals as well as the acquisition of KPC genes by different K. pneumoniae strains. All isolates were resistant to carbapenems, beta-lactams, ciprofloxacin, aminoglycosides and colistin, but intermediately susceptible to tigecycline and susceptible to gentamicin. The infection was fatal in five cases. The emergence of colistin-resistant K. pneumoniae possessing bla(KPC)(-2) underscores the implementation of strict control measures to prevent their dissemination of these organisms in hospitals.

Topics: Adult; Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; Carbapenems; Colistin; Cross Infection; Disease Outbreaks; DNA, Bacterial; Drug Resistance, Multiple, Bacterial; Female; Genotype; Greece; Hospitals; Humans; Klebsiella Infections; Klebsiella pneumoniae; Male; Middle Aged; Polymerase Chain Reaction

Reports of patients with polymyxin-only susceptible gram-negative nosocomial pneumonia treated with inhaled, but without concurrent intravenous, colistin are rare.. Patients admitted in a tertiary 450-bed tertiary care centre during the period 05/01/2005-05/31/2007 and receiving colistin through nebulization, but not systemically, were included in this retrospective case series.. Five patients (three with ventilator-associated pneumonia and two with nosocomial pneumonia) received colistin through nebulization without concomitant intravenous colistin. The isolated pathogens were Acinetobacter baumannii (three cases), Pseudomonas aeruginosa (one case) and the combination of Klebsiella pneumoniae, A. baumannii and P. aeruginosa (one case). They were susceptible only to colistin (three cases) or to colistin and gentamicin (two cases). Intravenous antimicrobial agents given concurrently were piperacillin/tazobactam, meropenem, ceftriaxone and ciprofloxacin; isolated pathogens were resistant to these agents. Four (80%) out of the five patients were cured, survived and were discharged. One patient died. No colistin-related adverse event was observed.. The experience from this case series and other relevant recent reports suggest that treatment of pneumonia due to polymyxin-only susceptible gram-negative bacilli with inhaled colistin (without concurrent systemic administration) deserves further careful investigation.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Administration, Inhalation; Adolescent; Adult; Aged; Aged, 80 and over; Anti-Bacterial Agents; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Female; Gram-Negative Bacterial Infections; Humans; Klebsiella Infections; Klebsiella pneumoniae; Male; Pneumonia, Bacterial; Pneumonia, Ventilator-Associated; Pseudomonas aeruginosa; Pseudomonas Infections; Retrospective Studies; Treatment Outcome

Nosocomial infections due to multi-drug resistant Acinetobacter baumannii are often treated with colistin, but there are few data comparing its safety and efficacy with other antimicrobials.. A retrospective cohort study of patients treated with colistin or tobramycin for A. baumannii infections in intensive care units (ICUs) at Groote Schuur hospital. Colistin was used for A. baumannii isolates which were resistant to all other available antimicrobials. In the tobramycin group, 53% of the isolates were only susceptible to tobramycin and colistin. We assessed ICU mortality, nephrotoxicity and time to the first negative culture.. 32 patients, with similar admission APACHE scores and serum creatinine, were treated with each antimicrobial. There were no significant differences between the colistin and tobramycin groups in ICU mortality (p=0.54), nephrotoxicity (p=0.67), change in creatinine from baseline to highest subsequent value (p=0.11) and time to microbiological clearance (p=0.75). The hazard ratio for total in-hospital survival in patients treated with colistin compared to tobramycin was 0.43 (95% CI 0.19 to 0.99).. Our study suggests that colistin and tobramycin have similar risks of nephrotoxicity and are equally efficacious. Colistin is an acceptable antibiotic for the treatment of A. baumannii infections when the organism is resistant to other available antimicrobials.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Adult; Anti-Bacterial Agents; Cohort Studies; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Humans; Intensive Care Units; Kaplan-Meier Estimate; Middle Aged; Retrospective Studies; Tobramycin; Treatment Outcome

Acinetobacter baumannii has emerged as an important nosocomial pathogen that can cause a multitude of severe infections. In neurosurgical patients the usual presentation is ventriculitis associated with external ventricular drainage. Carbapenems have been considered the gold standard for the treatment of Acinetobacter baumannii ventriculitis, but resistant isolates are increasing worldwide, reducing the therapeutic options. In many cases polymyxins are the only possible alternative, but their poor blood-brain barrier penetration could require them to be directly administered intraventricularly and clinical experience with this route is limited. We review the literature concerning intraventricular use of colistin (polymyxin E) for A. baumannii ventriculitis and add three cases successfully treated with this method. Our experience suggests that intraventricular colistin is a potentially effective and safe therapy for the treatment of multidrug-resistant A. baumannii central nervous system infections.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Adult; Anti-Bacterial Agents; Brain; Cerebrospinal Fluid Shunts; Colistin; Cross Infection; Drug Resistance, Multiple; Encephalitis; Fatal Outcome; Female; Humans; Hydrocephalus; Injections, Intraventricular; Lateral Ventricles; Male; Meningitis, Bacterial; Middle Aged; Subarachnoid Hemorrhage; Tomography, X-Ray Computed; Treatment Outcome; Ventriculostomy

Achromobacter xylosoxidans (formerly Alcaligenes xylosoxidans) is a rare but important nosocomial pathogen. Antibiotic resistance has been increasing during the past decade. A. xylosoxidans may be confused with Pseudomonas spp. but, unlike Pseudomonas spp., this organism has peritrichous flagella. Complicated intra-abdominal infection with A. xylosoxidans has rarely been reported in the literature. This report is of an immunocompetent patient with acute cholecystitis complicated by an intra-abdominal abscess after surgery. Culture of both blood and ascites yielded extended drug-resistant A. xylosoxidans, which was only sensitive to colistin. The clinical and laboratory characteristics of A. xylosoxidans are presented.

Topics: Abdominal Abscess; Achromobacter denitrificans; Adult; Anti-Bacterial Agents; Ascites; beta-Lactamases; Blood; Cholecystitis; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Gram-Negative Bacterial Infections; Humans; Male

The mechanisms responsible for the increasing prevalence of colistin-only-sensitive (COS) Pseudomonas aeruginosa isolates in a Spanish hospital were investigated. Pulsed-field gel electrophoresis revealed that 24 (50%) of the studied isolates belonged to the same clone, identified as the internationally spread sequence type 235 (ST235) through multilocus sequence typing. In addition to several mutational resistance mechanisms, an integron containing seven resistance determinants was detected. Remarkably, the extended-spectrum beta-lactamase GES-1 and its Gly170Ser carbapenem-hydrolyzing derivative GES-5 were first documented to be encoded in a single integron. This work is the first to describe GES enzymes in Spain and adds them to the growing list of beta-lactamases of concern (PER, VIM, and OXA) detected in ST235 clone isolates.

Topics: Anti-Bacterial Agents; Base Sequence; beta-Lactamases; Colistin; Cross Infection; Humans; Molecular Sequence Data; Pseudomonas aeruginosa

Colistin heteroresistance in Acinetobacter baumannii (Ab) has been reported, but the clinical impact and the antimicrobial treatment have not been established yet. We observed the selection intratreatment with colistin of Ab colistin-resistant strains from a colistin-heteroresistant isolate in one patient with postneurosurgical meningitis. The presence and the genetic relationship of heteroresistant Ab isolates from intensive care units (ICUs) obtained in the same period of the case report were analyzed. Twenty-eight isolates from patients admitted to the ICUs of an Argentinian university hospital during June to December 2004 were evaluated. Genomoespecie was determined by amplified ribosomal DNA restriction analysis, and genetic similarity among the strains was determined by pulsed-field electrophoresis. Colistin heteroresistance was observed in 46, 4% of these isolates. The majority belonged to clones previously identified as I and III.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; Argentina; Bacterial Typing Techniques; Cluster Analysis; Colistin; Cross Infection; DNA Fingerprinting; DNA, Bacterial; Drug Resistance, Bacterial; Electrophoresis, Gel, Pulsed-Field; Genotype; Hospitals, University; Humans; Intensive Care Units; Male; Meningitis, Bacterial; Ribotyping; Selection, Genetic; Young Adult

Acinetobacter spp. are the frequent causes of nosocomial infections which are difficult to treat due to multidrug resistance. The aim of this study was to determine the antibiotic susceptibilities and the presence of metallo-beta-lactamases in Acinetobacter spp. isolated from patients admitted to Hacettepe University Adult Hospital. A total of 124 Acinetobacter spp. isolates were included in the study. Antibiotic susceptibilities against imipenem (IMP), meropenem (MER), ceftazidime (CAZ), ciprofloxacin (CIP) and aztreonam (AZT) were studied by microdilution susceptibility testing according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. Multidrug-resistant isolates (MDR) were further tested for susceptibility against colistin by microdilution, and against amikacin (AN), piperacillin-tazobactam (PIP-TAZ), cefepime (FEP), ceftriaxone (CRO), tetracycline (TET), trimetoprim-sulfomethoxazole (SXT) and mezlocillin (MEZ) by disk diffusion method according to CLSI guidelines. Each isolate was also tested for metallo-beta-lactamase (MBL) production by using IMP and EDTA combined disk diffusion test and molecular analysis for bla(IMP-1) and bla(VIM-2) genes was done by polymerase chain reaction (PCR). Among 124 non-duplicate isolates, 72 were identified as Acinetobacter baumannii and 52 as Acinetobacter lwoffii. Minimum inhibitor concentration 50 (MIC50) and minimum inhibitor concentration 90 (MIC90) values of the isolates were 32 and 128 microg/ml for IMP, 16 and 32 microg/ml for MER, 128 and 256 microg/ml for CIP, 64 and 256 microg/ml for CAZ, 128 and 256 microg/ml for AZT, respectively. Forty-three (34.7%) isolates were susceptible to IMP. Overall, 51 (41%) Acinetobacter spp. were found to be resistant to > or = 3 antibiotics belonging to different antimicrobial classes and defined as MDR. Colistin MIC50 and MIC90 values were 2 and 8 microg/ml, respectively and the rate of colistin resistance was 27.5% in MDR isolates. The resistance rates for AN, PIP-TAZ, FEP, CRO, TET, SXT and MEZ were 80.4%, 98%, 92.2%, 100%, 100%, 86.3% and 86.3%, respectively. Among 124 isolates, 64 (51.6%) yielded positive result by IMP-EDTA combined disk test, and all the isolates were negative in terms of the tested MBL genes by PCR. These data revealed high level resistance among the Acinetobacter population in our hospital. The high rate of carbapenem resistance and increasing colistin resistance among Acinetobacter isolates should be surveyed cautiously. The incr

Topics: Acinetobacter; Acinetobacter Infections; Adult; Anti-Bacterial Agents; beta-Lactamases; Carbapenems; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Hospitals, University; Humans; Microbial Sensitivity Tests; Turkey

Forty-two multidrug-resistant (MDR) Acinetobacter baumannii isolates were obtained during outbreaks in a Korean hospital. The co-carriage of bla(OXA-23), bla(OXA-51), bla(PER-1) and armA was observed in 23 isolates, and they were susceptible only to colistin and minocycline. The MDR A. baumannii isolates were found to belong to sequence group 1 using sequence-based typing.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Bacterial Typing Techniques; beta-Lactamase Inhibitors; beta-Lactamases; Carbapenems; Colistin; Cross Infection; Disease Outbreaks; DNA, Bacterial; Drug Resistance, Multiple, Bacterial; Humans; Korea; Microbial Sensitivity Tests; Minocycline; Polymerase Chain Reaction; Sequence Analysis, DNA

Tracheotomy is considered to be an independent risk factor for ventilator-associated pneumonia (VAP). Antimicrobial prophylaxis, in particular with coverage of Pseudomonas aeruginosa, is presently advocated. Selective decontamination of the digestive tract (SDD) aims to prevent VAP in critically ill patients, including those after tracheotomy. We determined the incidence and microbial spectrum of VAP after tracheotomy in a SDD-setting.. Retrospective analysis of 231 tracheotomized patients during a 2-year period.. Thirteen patients (5.6%) developed VAP. The median [IQR] day of onset was 8.0 [3.0-10.5] days after tracheotomy. The most predominant causative pathogen was Methicillin-sensitive Staphylococcus aureus (MSSA). Timing of tracheotomy was not different between patients developing VAP and those who did not. The type of tracheotomy (percutaneous or surgical, 84.6% versus 15.4%) had no significant influence on the incidence of VAP.. The incidence of VAP after tracheotomy in a SDD-setting is low, with MSSA as the predominant causative pathogen. Accordingly, if antimicrobial prophylaxis is considered, it may be advisable to cover MSSA in an SDD-setting.

Topics: Administration, Buccal; Adult; Aged; Amphotericin B; Anti-Bacterial Agents; Antibiotic Prophylaxis; Colistin; Critical Illness; Cross Infection; Decontamination; Enteral Nutrition; Female; Gastrointestinal Tract; Humans; Incidence; Intensive Care Units; Male; Methicillin; Microbial Sensitivity Tests; Middle Aged; Netherlands; Pneumonia, Ventilator-Associated; Retrospective Studies; Risk Factors; Staphylococcus aureus; Tobramycin; Tracheotomy

Topics: Acinetobacter baumannii; Acinetobacter Infections; Aged; Amikacin; Brain Ischemia; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Drug Therapy, Combination; Fatal Outcome; Humans; Hydrocephalus; Injections, Spinal; Male; Meningitis, Bacterial; Pseudomonas Infections; Shock, Septic; Surgical Wound Infection; Ventriculostomy

The increased incidence of nosocomial infections by multidrug-resistant organisms has motivated the re-introduction of colistin in combination with other antimicrobials in the treatment of infections. We describe the clinical and microbiological outcomes of patients infected with multidrug-resistant Acinetobacter baumannii who were treated with a combination of colistin and rifampicin.. Critically ill patients with pneumonia and bacteraemia caused by A. baumannii resistant to all antibiotics except colistin in medical and surgical intensive care units were enrolled. Clinical and microbiological responses and safety were evaluated.. Twenty-nine patients (47 +/- 14 years and APACHE II score 17.03 +/- 3.68), of whom 19 were cases of nosocomial pneumonia and 10 were cases of bacteraemia, were treated with intravenous colistin sulphomethate sodium (2 million IU three times a day) in addition to intravenous rifampicin (10 mg/kg every 12 h). All A. baumannii isolates were susceptible to colistin. The mean duration of treatment with intravenous colistin and rifampicin was 17.7 (+/-10.4) days (range 7-36). Clinical and microbiological responses were observed in 22 of 29 cases (76%) and the overall infection-related mortality was 21% (6/29). Three of the 29 evaluated patients (10%) developed nephrotoxicity when treated with colistin, all of whom had previous renal failure. No cases of renal failure were observed among patients with normal baseline renal function. No neurotoxicity was noted.. Colistin and rifampicin appears to be an effective and safe combination therapy for severe infections due to multidrug-resistant A. baumannii.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Adult; Aged; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Drug Therapy, Combination; Humans; Middle Aged; Prospective Studies; Rifampin; Treatment Outcome

The study aimed to determine the incidence and mortality of multidrug-resistant Acinetobacter baumannii in cardiac surgery, to elucidate the effectiveness of colistin treatment and to identify if the additional measures to the recommended procedures were able to control the dissemination of the pathogen.. A prospective observational cohort was conducted among cardiac surgical patients from 1 September 2005 to 31 December 2006. We reviewed the prophylactic measures of the surgical intensive care unit and implemented a two scale multiple program. Scale I included classical infection control measures, while Scale II referred to the geographic isolation of multidrug-resistant Acinetobacter baumannii patients and environmental intense surveillance.. Among 151 out of 1935 infected patients 20 were colonized and infected by strains of multidrug-resistant A. baumannii susceptible only to colistin. Seventeen patients presented respiratory tract infection, one patient suffered deep surgical site infection and two patients catheter related infection. Transmission of the pathogen occurred via two patients transferred from two other institutions. They were all treated with colistin. Cure or clinical improvement was observed only in four patients (20%). Scale I measures were implemented for the whole 16-month period while scale II for two separate periods of 3 weeks. Environmental specimens (n>350) proved negative.. The increasing prevalence of multidrug-resistant A. baumannii in surgical intensive care unit patients creates demand on strict screening and contact precautions. Following this infection control strategy we were able to achieve intermittent eradication of the pathogen during a 16-month period with continuous function of the intensive care unit. Despite the significant in vitro activity of colistin against multidrug-resistant Acinetobacter baumannii the results were discouraging.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Aged; Anti-Bacterial Agents; Cardiac Surgical Procedures; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Female; Humans; Intensive Care Units; Male; Middle Aged; Postoperative Care; Prospective Studies; Risk Factors; Treatment Outcome

Post-surgical meningitis and/or ventriculitis caused by Gram-negative bacteria may be difficult to treat due to the emergence of multiresistant strains. Two patients with multiresistant Acinetobacter baumannii central nervous system infection, successfully treated with either intravenous and/or intraventricular colistin are presented. Unresolved issues such as dose and duration of intraventricular colistin are discussed.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Adult; Aneurysm, Ruptured; Anti-Bacterial Agents; Colistin; Craniocerebral Trauma; Cross Infection; Device Removal; Drug Resistance, Multiple, Bacterial; Female; Humans; Hydrocephalus; Injections, Intraventricular; Intracranial Aneurysm; Male; Postoperative Complications; Ventriculoperitoneal Shunt

This study reviewed 56 patients with significant metallo-beta-lactamase (MBL)-producing Pseudomonas aeruginosa infections between May 2002 and March 2004 to identify features associated with mortality. Immunosuppression (p 0.002), bacteraemia (p 0.08) and inadequate antimicrobial therapy (p <0.001) were associated with death. Among those patients treated with adequate therapy, the use of multiple drug treatment regimens (two or three active agents) was associated with a non-significant two-fold increase in survival (p 0.45). Further prospective studies are warranted to determine the optimal treatment of MBL-producing P. aeruginosa infections.

Topics: Aged; Anti-Bacterial Agents; Aztreonam; beta-Lactamases; Canada; Catchment Area, Health; Colistin; Cross Infection; Female; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Pseudomonas aeruginosa; Pseudomonas Infections; Retrospective Studies; Survival Rate

We investigated an outbreak of Acinetobacter baumannii in the intensive care unit (ICU) of a hospital in Rome, Italy. The outbreak involved 14 patients whose isolates were most frequently recovered from bronchoalveolar lavage. All isolates were multidrug-resistant and showed diminished susceptibility or resistance to carbapenems. A. baumannii strains with a similar antibiotic susceptibility pattern were isolated from the environment. Pulsed-field gel electrophoresis identified a single clone from both the patients' and environmental isolates. Because of the lack of a single source of infection, the eradication of the epidemic required a broad approach, including contact isolation and cohorting, aggressive environmental disinfection, and close monitoring of the ward staff's performance. Infected patients were successfully treated with combined therapy. Although considered of low virulence, A. baumannii can be particularly aggressive and difficult to treat in ICU patients.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Adult; Aged; Aged, 80 and over; Ampicillin; Anti-Bacterial Agents; Bronchoalveolar Lavage Fluid; Carbapenems; Colistin; Cross Infection; Disease Outbreaks; Disinfection; Drug Resistance, Multiple, Bacterial; Electrophoresis, Gel, Pulsed-Field; Female; Humans; Intensive Care Units; Male; Middle Aged; Patient Isolation; Rifampin; Rome; Sulbactam

We present our experience with five cases of pandrug-resistant Pseudomonas aeruginosa ventilator-associated pneumonia (VAP) and analysis of risk factors.. Case-control study in a 15-bed intensive care unit (ICU).. The study included 5 cases and 20 controls. Each case patient was matched to four contemporary controls according to gender, prior hospital admissions, hospitalization duration, ICU admission cause, Acute Physiology and Chronic Health Evaluation (APACHE) II and Sequential Organ Function Assessment (SOFA) scores on ICU admission, and length of ICU stay, and mechanical ventilation duration until first VAP episode by a multidrug-resistant bacterium.. Recorded variables included age, gender, daily APACHE II and SOFA scores, patient medication, treatment interventions, positive cultures and corresponding antibiograms, occurrence of infection, sepsis, and septic shock, other ICU-associated morbidity, length of ICU stay and mechanical ventilation, and patient outcome. Healthcare worker and environmental cultures, and a hand-disinfection survey were performed. Pandrug-resistant P. aeruginosa isolates belonged to the same genotype and were bla (VIM-1)-like gene positive. The outbreak resolved following reinforcement of infection-control measures (September 27). The sole independent predictor for pandrug-resistant P. aeruginosa VAP was combined use of carbapenem for more than 20 days and colistin use for and more than 13 days (odds ratio 76.0; 95% confidence interval 3.7-1487.6). An additional risk factor was more than 78 open suctioning procedures during 6-26 September (odds ratio 16.0; 95% confidence interval 1.4-185.4).. Prolonged carbapenem-colistin use predisposes to VAP by pandrug-resistant P. aeruginosa. Cross-transmission may be facilitated by open suctioning.

Topics: Anti-Bacterial Agents; Carbapenems; Case-Control Studies; Colistin; Cross Infection; Disease Outbreaks; Disease Susceptibility; Drug Resistance, Multiple, Bacterial; Drug Therapy, Combination; Female; Hand Disinfection; Humans; Intensive Care Units; Logistic Models; Male; Middle Aged; Pneumonia, Ventilator-Associated; Pseudomonas aeruginosa; Risk Factors; Suction

Increasing antibiotic resistance in gram-negative bacteria has recently renewed interest in colistin as a therapeutic option. The increasing use of colistin necessitates the availability of rapid and reliable methods for colistin susceptibility testing. We compared seven methods of colistin susceptibility testing (disk diffusion, agar dilution on Mueller-Hinton [MH] and Isosensitest agar, Etest on MH and Isosensitest agar, broth microdilution, and VITEK 2) on 102 clinical isolates collected from patient materials during a selective digestive decontamination or selective oral decontamination trial in an intensive-care unit. Disk diffusion is an unreliable method to measure susceptibility to colistin. High error rates and low levels of reproducibility were observed in the disk diffusion test. The colistin Etest, agar dilution, and the VITEK 2 showed a high level of agreement with the broth microdilution reference method. Heteroresistance for colistin was observed in six Enterobacter cloacae isolates and in one Acinetobacter baumannii isolate. This is the first report of heteroresistance to colistin in E. cloacae isolates. Resistance to colistin in these isolates seemed to be induced upon exposure to colistin rather than being caused by stable mutations. Heteroresistant isolates could be detected in the broth microdilution, agar dilution, Etest, or disk diffusion test. The VITEK 2 displayed low sensitivity in the detection of heteroresistant subpopulations of E. cloacae. The VITEK 2 colistin susceptibility test can therefore be considered to be a reliable tool to determine susceptibility to colistin in isolates of genera that are known not to exhibit resistant subpopulations. In isolates of genera known to (occasionally) exhibit heteroresistance, an alternative susceptibility testing method capable of detecting heteroresistance should be used.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Agar; Anti-Bacterial Agents; Bacterial Infections; Colistin; Cross Infection; Culture Media; Drug Resistance, Multiple, Bacterial; Enterobacter cloacae; Enterobacteriaceae Infections; Humans; Intensive Care Units; Microbial Sensitivity Tests; Polymyxin B

Nosocomial outbreaks caused by multidrug-resistant (MDR) Pseudomonas aeruginosa have been associated to fibrocystic patients and isolates harboring metallo-beta-lactamase (MBL) genes. Genotyping is an important tool for interpreting bacterial nosocomial outbreaks and implementing adequate control strategies. The aim of this study was to evaluate whether an outbreak of MDR P. aeruginosa occurring in different hospitals was due to a unique clone or independent isolates. From 2000 to 2003, 108 P. aeruginosa were recovered from colonized/infected inpatients in hospitals of São Luís, Maranhão, Brazil. The susceptibility test was performed with antipseudomonal drugs, and the presence of MBL genes were verified by PCR. Isolates were genotyped by pulsed-field gel electrophoresis (PFGE). The majority of strains was multiresistant including a great number presenting the colistin-only-sensitive (COS) profile. PFGE analysis revealed 54 genotypes, with predominance of three major COS clones (A, C, and E) coexisting at different moments and hospitals. Clone A harbored the bla(SPM) gene. Eight unique genotypes also had the COS profile. Other eight MDR genotypes presented isolates with differences in resistance profiles. Here we detected, for the first time, the coexistence of COS P.aeruginosa genotypes disseminated in several hospitals during long periods, attacking patients under various clinical conditions.

Topics: Anti-Bacterial Agents; Brazil; Colistin; Cross Infection; Disease Outbreaks; Disk Diffusion Antimicrobial Tests; Drug Resistance, Multiple, Bacterial; Electrophoresis, Gel, Pulsed-Field; Genes, Bacterial; Genotype; Hospitals; Humans; Polymerase Chain Reaction; Pseudomonas aeruginosa; Pseudomonas Infections

Carbapenem resistance in Acinetobacter spp. is an emerging problem in China. We investigated the molecular epidemiology and carbapenemase genes of 221 nonrepetitive imipenem-resistant clinical isolates of Acinetobacter spp. collected from 1999 to 2005 at 11 teaching hospitals in China. Genotyping by pulsed-field gel electrophoresis (PFGE) found 15 PFGE patterns. Of these, one (clone P) was identified at four hospitals in Beijing and another (clone A) at four geographically disparate cities. Most imipenem-resistant isolates exhibited high-level resistance to all beta-lactams and were only susceptible to colistin. bla(OXA-23)-like genes were found in 97.7% of isolates. Sequencing performed on 60 representative isolates confirmed the presence of the bla(OXA-23) carbapenemase gene. Analysis of the genetic context of bla(OXA-23) showed the presence of ISAba1 upstream of bla(OXA-23). All of the 187 A. baumannii isolates identified by amplified RNA gene restriction analysis carried a bla(OXA-51)-like oxacillinase gene, while this gene was absent from isolates of other species. Sequencing indicated the presence of bla(OXA-66) for 18 representative isolates. Seven isolates of one clone (clone T) carried the plasmid-mediated bla(OXA-58) carbapenemase gene, while one isolate of another clone (clone L) carried the bla(OXA-72) carbapenemase gene. Only 1 isolate of clone Q carried the bla(IMP-8) metallo-beta-lactamase gene, located in a class 1 integron. Of 221 isolates, 77.8% carried bla(PER-1)-like genes. Eleven different structures of class 1 integrons were detected, and most integrons carried genes mediating resistance to aminoglycosides, rifampin, and chloramphenicol. These findings indicated clonal spread of imipenem-resistant Acinetobacter spp. and wide dissemination of the OXA-23 carbapenemase in China.

Topics: Acinetobacter; Acinetobacter Infections; Aminoglycosides; Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; beta-Lactams; Blotting, Southern; Carbapenems; China; Chloramphenicol; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Electrophoresis, Gel, Pulsed-Field; Hospitals; Humans; Imipenem; Integrons; Microbial Sensitivity Tests; Molecular Epidemiology; Molecular Sequence Data; Rifampin; Sequence Analysis, DNA

Multi-drug resistant (MDR) organisms in intensive care units (ICUs) are a growing concern. The emergence of several infections with MDR Acinetobacter baumannii prompted a review of cases and evaluation of the efficacy of intervention.. To determine the rate of clinical cure, the incidence of drug resistance, and the mortality rate associated with A. baumannii infection.. Retrospective review of A. baumannii infections in three surgical ICUs between January, 2004 and November, 2005. Infection was identified in 291 patients, 20 of whom were excluded because of incomplete documentation. Of the remaining 271 patients, 71% were male, and the mean age was 47 +/- 18 years (range 13-90 years).. Patients had a mean length of stay in the ICU of 14 days (range 0-136 days) before infection. The initial positive cultures were from bronchoalveolar lavage fluid (BAL) in 72.3%, blood in 16.2%, a catheter tip in 6.3%, urine in 1.8%, wound in 2.2%, and abscess in 1.1%. In 46.9% of patients, the first culture was polymicrobial. The Acinetobacter isolates were resistant or intermediate-resistant to imipenem-cilastatin in 81.2% of cases; 19.9% were resistant to all drugs except colistin, and two were resistant to all tested drugs. Colistin was used in 75.6% of patients (intravenous 61.5%, nebulized 38.5%). The mean duration of treatment was 13 +/- 8.9 days (range 0-56 days), and clinical cure was achieved in 73.8% of patients. Recurrent infection after initial cure was found in 19.2% of patients. There was no significant difference in clinical cure rates between patients treated with colistin and those treated with other culture-directed drugs (75.1% vs. 69.7%), or between patients treated with intravenous vs. nebulized colistin (72.4% vs. 79.5%). The mortality rate was 26.2% for the entire group and was significantly higher in the subgroup of transplant patients (n = 31) (64.5% vs. 21.4%; p < 0.001).. The majority of A. baumannii isolates were MDR, and a significant proportion were sensitive only to colistin. Treatment of A. baumannii infection with colistin is effective by both intravenous and nebulized routes of administration. However, infection with A. baumannii in critically ill surgical patients is associated with a high mortality rate, particularly in transplant patients.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Adolescent; Adult; Aged; Aged, 80 and over; Anti-Bacterial Agents; Colistin; Critical Illness; Cross Infection; Drug Resistance, Multiple, Bacterial; Female; Florida; Hospital Mortality; Humans; Immunosuppression Therapy; Incidence; Intensive Care Units; Male; Middle Aged; Organ Transplantation; Retrospective Studies

Emergence of panresistant gram negative bacilli has lead to the progressive reintroduction of intravenous colistin.. To describe the clinical experience observed with this compound.. A retrospective analysis was performed for all treatments lasting >/= 48 hours. Medical records were analyzed to obtain clinical parameters and microbiological data, evaluate clinical response and evolution until discharge.. 24 treatments lasting >/= 48 hours were applied between June 2005 and September 2006. Intravenous colistin was indicated to treat cases of ventilator-associated (VA) pneumonia (n = 10; 41.7%), abscess or collections (12.5%), bloodstream infections, non-VA pneumonia or urinary tract infections (4.2% each one, respectively). Treatment was initiated on average at 3.2 days (+/- 2.85) from diagnosis of infection. All courses were microbiologically-guided, and involved P. aeruginosa or A. baumannii isolates. Susceptibility was evaluated by E-test in 11 isolates (MIC90 3.6 nicrog/mL, range 0.38 to 4 microg/mL). One isolate was resistant to colistin (9%). A favorable response was observed in 12 treatments (50%) with a relapse in 5 cases (41.7%). Being treated for pneumonia was the only factor associated to failure, (p = 0.04) Eradication was documented in 8 cases (33.3%) and persistence in 11 (45.8%). In 5 cases a microbiological follow-up was not available. Survival at time of discharge was 45.5%. (n = 10) None of the treatment courses was associated with nefrotoxicity.. Intravenous colistin is a safe compound useful to treat various nosocomial infections due to pan-resistant gram negative bacilli. Nonetheless, its clinical efficacy is limited, especially among patients treated for nosocomial pneumonia.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Adolescent; Adult; Aged; Aged, 80 and over; Anti-Bacterial Agents; APACHE; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Female; Humans; Male; Middle Aged; Pseudomonas aeruginosa; Pseudomonas Infections; Retrospective Studies; Treatment Outcome

Multidrug resistant Gram-negative rods are increasingly isolated from clinical specimens, especially from hospitalized patients. The aim of this study was to evaluate the prevalence of imipenem resistant strains of Gram-negative rods isolated in dr. A. Jurasz University Hospital in Bydgoszcz between 1999 and 2005 and imipenem consumption in this period. Out of 109614 isolated microorganisms, Gram-negative rods were 28,5%, 637 (2,0%) of strains were resistant to imipenem. These strains were isolated mostly from patients hospitalized in intensive care and rehabilitation clinics. Among imipenem-resistant strains Pseudomonas aeruginosa prevailed (88,9%). P. aeruginosa strains were sensitive to colistin, 45,5% of them to aztreonam and 44,0% to ceftazidime. The imipenem consumption in the appropriate years included in this study was: 805,00; 1201,25; 940,00; 1390,00; 1660,00; 1341,25; 1841,25 DDD respectively, and was strictly connected with increasing imipenem-resistant Gram-negative rods isolation.

Topics: Anti-Bacterial Agents; Aztreonam; beta-Lactam Resistance; Carbapenems; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Gram-Negative Bacterial Infections; Humans; Imipenem; Intensive Care Units; Microbial Sensitivity Tests; Retrospective Studies

Topics: Acinetobacter baumannii; Acinetobacter Infections; Adult; Anti-Bacterial Agents; Colistin; Craniocerebral Trauma; Cross Infection; Drug Resistance, Bacterial; Humans; Injections, Spinal; Male; Meningitis, Bacterial

Topics: Acinetobacter baumannii; Acinetobacter Infections; Adult; Aged; Anti-Bacterial Agents; Colistin; Combined Modality Therapy; Cross Infection; Drug Resistance, Multiple, Bacterial; Drug Therapy, Combination; Female; Humans; Male; Middle Aged; Pneumonia, Bacterial; Respiration, Artificial; Rifampin

Topics: Acinetobacter baumannii; Anti-Bacterial Agents; Colistin; Cross Infection; Humans; Monitoring, Physiologic; Pseudomonas aeruginosa; United States

To assess the distribution of bacterial species and antimicrobial resistance in an ICU during long-term use of selective digestive decontamination (SDD) in the context of national reference data.. Five-year prospective observational study in a 24-bed interdisciplinary surgical ICU of a university hospital (study ICU) participating in the project "Surveillance of Antimicrobial Use and Antimicrobial Resistance in German Intensive Care Units" (SARI; reference ICUs).. Resistance data were obtained from all patients; patients intubated for at least 2 days received SDD (colistin, tobramycin, amphotericin B).. SDD was performed in 1,913 of 7,270 patients. Antimicrobial resistance was examined in 4,597 (study ICU) and 46,346 (reference ICUs) isolates.. Methicillin-resistant Staphylococcus aureus (MRSA) remained stable (2.76 and 2.58 isolates/1000 patient days) in the study ICU; this was below the German average (4.26 isolates/1000 patient days). Aminoglycoside- and betalactam-resistant Gram-negative rods did not increase during SDD use. Aminoglycoside resistance of Pseudomonas aeruginosa was 50% below the mean value of SARI (0.24 vs. 0.52 isolates/1,000 patient days). The relative frequency of enterococci and coagulase-negative staphylococci (CNS) was higher than in the SARI ICUs (23.2% vs. 17.3%, and 25.0% vs. 20.6%, respectively).. Routine 5-year-use of SDD was not associated with increased antimicrobial resistance in our ICU with low baseline resistance rates. Vigorous surveillance and control measures to search and destroy MRSA were considered a mandatory component of the SDD program. The relative increase in enterococci and CNS is of concern requiring further investigation.

Topics: Amphotericin B; Anti-Bacterial Agents; Colistin; Cross Infection; Digestive System; Drug Resistance, Bacterial; Female; Humans; Intensive Care Units; Male; Methicillin Resistance; Microbial Sensitivity Tests; Patient Isolation; Population Surveillance; Prospective Studies; Tobramycin

The objective of this study was to determine the efficacy of systemic colistin therapy in the treatment of nosocomial infections caused by multidrug-resistant Acinetobacter baumannii or Pseudomonas aeruginosa and to study related adverse events. We prospectively studied 78 infections caused by multidrug-resistant A. baumannii or P. aeruginosa that were treated with colistin. The sites of infection were pulmonary infection (78.2%), urinary tract infection (7.7%), primary bloodstream infection (11.5%) and meningitis (2.6%). The mean daily dose of colistin was 5.5+/-1.1 MU/day (range 2-9 MU/day) and the mean duration of colistin therapy was 9.3+/-3.8 days (range 5-21 days). A favourable clinical response to colistin occurred in 60 cases (76.9%). Renal failure occurred in only seven cases. We conclude that colistin can be a safe and effective salvage therapeutic option for nosocomial infections caused by multidrug-resistant A. baumannii or P. aeruginosa.

Topics: Acinetobacter Infections; Anti-Bacterial Agents; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Humans; Intensive Care Units; Prospective Studies; Pseudomonas Infections; Salvage Therapy; Treatment Outcome

A retrospective case series study was performed in a 30-bed general intensive care unit (ICU) of a tertiary care hospital to assess the effectiveness and safety of colistin in 43 critically ill patients with ICU-acquired infections caused by multiresistant Gram-negative bacteria. Various ICU-acquired infections, mainly pneumonia and bacteraemia caused by multiresistant strains of Pseudomonas aeruginosa and/or Acinetobacter baumannii, were treated with colistin. Good clinical response (cure or improvement) was noted in 74.4% of patients. Deterioration of renal function occurred in 18.6% of patients during colistin therapy. Nephrotoxicity was elevated significantly in those patients with a history of renal failure (62.5%). All-cause mortality amounted to 27.9%. In this group of critically ill patients, an age of >50 years (OR, 5.4; 95% CI 1.3-24.9) and acute renal failure (OR, 8.2; 95% CI 2.9-23.8) were independent predictors of mortality. Colistin should be considered as a treatment option in critically ill patients with infection caused by multiresistant Gram-negative bacilli.

Topics: Adult; Aged; Anti-Bacterial Agents; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Female; Gram-Negative Bacterial Infections; Humans; Intensive Care Units; Male; Middle Aged; Retrospective Studies

The clinical and economic consequences of the emergence of multidrug-resistant Gram-negative bacteria in the intensive care unit (ICU) setting, combined with the high mortality rate among patients with nosocomial pneumonia, have stimulated a search for alternative therapeutic options to treat such infections. The use of adjunctive therapy with aerosolized colistin represents one of these. There is extensive experience with use of aerosolized colistin by patients with cystic fibrosis, but there is a lack of data regarding the use of aerosolized colistin in patients without cystic fibrosis.. We conducted the present study to assess the safety and effectiveness of aerosolized colistin as an adjunct to intravenous antimicrobial therapy for treatment of Gram-negative nosocomial pneumonia. We retrospectively reviewed the medical records of patients hospitalized in a 450-bed tertiary care hospital during the period from October 2000 to January 2004, and who received aerosolized colistin as adjunctive therapy for multidrug-resistant pneumonia.. Eight patients received aerosolized colistin. All patients had been admitted to the ICU, with mean Acute Physiological and Chronic Health Evaluation II scores on the day of ICU admission and on day 1 of aerosolized colistin administration of 14.6 and 17.1, respectively. Six of the eight patients had ventilator-associated pneumonia. The responsible pathogens were Acinetobacter baumannii (in seven out of eight cases) and Pseudomonas aeruginosa (in one out of eight cases) strains. Half of the isolated pathogens were sensitive only to colistin. The daily dose of aerosolized colistin ranged from 1.5 to 6 million IU (divided into three or four doses), and the mean duration of administration was 10.5 days. Seven out of eight patients received concomitant intravenous treatment with colistin or other antimicrobial agents. The pneumonia was observed to respond to treatment in seven out of eight patients (four were cured and three improved [they were transferred to another facility]). One patient deteriorated and died from septic shock and multiple organ failure. Aerosolized colistin was well tolerated by all patients; no bronchoconstriction or chest tightness was reported.. Aerosolized colistin may be a beneficial adjunctive treatment in the management of nosocomial pneumonia (ventilator associated or not) due to multidrug-resistant Gram-negative bacteria.

Topics: Aerosols; Anti-Bacterial Agents; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Female; Humans; Intensive Care Units; Male; Middle Aged; Pneumonia, Bacterial; Treatment Outcome

The management challenges of patients with nosocomial pneumonia are great because of resistance among the responsible pathogens. In this issue of Critical Care, Argyris Michalopoulos and colleagues describe the use of inhaled colistin in the treatment of multidrug-resistant Gram-negative nosocomial pneumonia in a small group of patients. Although seven of eight patients who received nebulized colistin showed clinical improvement, some patients also received other active antibiotics. Microbiological eradication was demonstrated in only four of the eight patients. Serum levels of colistin were not measured. In addition, although adverse events were not documented in patients receiving colistin, formal assessments for bronchoconstriction and neurological toxicity were not completed in this retrospective study. Although resistance to colistin in Gram-negative organisms has not evolved, the risk of breakthrough infection with Gram-positive and inherently resistant Gram-negative bacteria remains a concern. The results of this limited study do, however, suggest that further studies examining the use of nebulized colistin are merited.

Topics: Aerosols; Anti-Bacterial Agents; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Gram-Negative Bacteria; Humans; Pneumonia; Retrospective Studies

Topics: Acinetobacter baumannii; Acinetobacter Infections; Administration, Inhalation; Aerosols; Anti-Bacterial Agents; Colistin; Cross Infection; Drug Resistance, Multiple, Bacterial; Humans; Infusions, Intravenous; Pneumonia, Bacterial; Pseudomonas aeruginosa; Pseudomonas Infections; Treatment Outcome

We report a case of serious nosocomial meningitis due to a multidrug-resistant Acinetobacter baumannii in a 23-year-old woman who had a posterior fossa craniotomy with upper cervical laminectomy for excision of a meningioma at the level of foramen magnum. Post-operatively, she had neck pain with continuous fever and deterioration in the level of consciousness and convulsions. The CSF was turbid and had neutrophil pleocytosis. A multidrug-resistant Acinetobacter baumannii was isolated from the blood and CSF. The patient failed high doses of imipenem, ciprofloxacin and systemic colistin but responded well to intraventricular injections of colistin 125,000 units twice daily for 3 weeks. No apparent side effects were noticed. We have reviewed other similar cases reported in the literature.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Adult; Anti-Bacterial Agents; Colistin; Cross Infection; Drug Resistance, Microbial; Female; Humans; Injections, Intraventricular; Meningitis, Bacterial; Treatment Outcome

A multicenter study was conducted to obtain "in vitro" chloramphenicol and colistin susceptibility data on multiresistant hospital bacterial pathogens in Slovak Republic.. During the period of April-June 2001, 628 clinical bacterial multiresistant isolates from patients with serious infections were selected in 10 hospitals and tested to a large scale of antibiotics by means of a microdilution method. The strains expressed either a significant resistance phenotype (ESBL, MRSA, CoNMRS, MLSB/c, efflux in Ps. aeruginosa), or were resistant to one or more preparations in at least half of reliable unrelated antibiotic groups (beta-lactams, aminoglycosides, quinolons, macrolides).. Both chloramphenicol and colistin retained significant "in vitro" activity against many multiresistant hospital bacterial pathogens. The highest activity of chloramphenicol was documented for isolates of Stenotrophomonas maltophilia (76,5 % susceptible, MIC50 = 4 mg/L, MIC90 = 16 mg/L) and of Staphylococcus aureus (76,2 % susceptible, MIC50 = 8 mg/L, MIC90 = 16 mg/L). In tested Pseudomonas aeruginosa (82,5 % susceptible, MIC50 = 2 mg/L, MIC90 = 16 mg/L) and Stenotrophomonas maltophilia (88,2 % susceptible, MIC50 = 1 mg/L, MIC90 = 8 mg/L) isolates colistin represented the most "in vitro" effective antibiotic. Colistin was the only "in vitro" effective antimicrobial in four of 120 multiresistant Pseudomonas aeruginosa isolates tested in our study.. The study confirmed a good "in vitro" susceptibility of many multiresistant hospital bacterial pathogens to chloramphenicol and colistin in Slovak Republic. The clinical application of chloramphenicol and colistin might be reconsidered in infections caused by extremely resistant bacteria with prooved susceptibility to these antibiotics. It is important to consider, that the infection danger has to exceed the risk of antibiotic toxicity.

Topics: Anti-Bacterial Agents; Chloramphenicol; Colistin; Cross Infection; Drug Resistance, Bacterial; Humans; Microbial Sensitivity Tests; Pseudomonas aeruginosa; Staphylococcus aureus

An outbreak of a multidrug resistant Pseudomonas aeruginosa including imipenem resistance occurred in the urology intensive care unit at Charles Nicolle Hospital (Tunis). All isolates presented the same antibiotic resistance pattern and were only susceptible to colistin. The epidemic strain was detected in different sites of this unit. Pulsed-field gel electrophoresis after enzymatic restriction using XbaI was performed in order to establish an epidemiologic link between these infections. Genotypic analysis showed two different patterns and the environmental source was identified in both cases. Although the same antibiotype was harbored by all the isolates, two outbreaks occurring in the same period were identified. The strengthening of hygiene measures allowed to stop the outbreak spreading. Since the hospital environment is the major source of Pseudomonas aeruginosa contamination, a continuous surveillance of the patients and the environmental sources is required for the implementation efficient control measures.

Topics: Colistin; Cross Infection; Disease Outbreaks; Drug Resistance, Bacterial; Drug Resistance, Multiple; Electrophoresis, Gel, Pulsed-Field; Genotype; Pseudomonas aeruginosa; Pseudomonas Infections; Urinary Tract Infections

To determine whether selective digestive decontamination (SDD) had some negative impact on the bacterial resistance observed in strains isolated from samples from patients receiving nonabsorbable antibiotics and cefazolin.. Case-control study.. Intensive care unit of a university tertiary-care hospital.. Over a 6-yr period, 360 multiple trauma patients (case patients) submitted to SDD were compared with 360 patients not receiving SDD (controls).. SDD consisted of polymyxin E, gentamicin, and amphotericin B and was applied on the buccal mucosa and provided in the nares and the stomach. For the first 3 days, systemic cefazolin (1 g three times a day) was provided. Resistance analysis was performed in case patients and controls on samples collected at predetermined intervals.. SDD was used in a small subset of patients admitted to the intensive care unit (360 of 5987 over the 6-yr study period). A relative overgrowth of gram-positive cocci was observed. Methicillin resistance of Staphylococcus epidermidis was increased (SDD 76%, controls 63%, p <.05) but not that of Staphylococcus aureus (SDD 20%, controls 18%). Resistance of Enterobacteriaceae, Pseudomonas aeruginosa, and Acinetobacter to beta-lactamines and aminoglycosides was the same in SDD patients and controls.. When used in a small subset of patients who have been shown to derive benefit from it (patients who have experienced multiple trauma), SDD has a moderate impact on microbial ecology. However, surveillance cultures are indispensable because the absence of resistance to SDD antibiotics determines the long-term safety of the SDD prophylaxis.

Topics: Administration, Cutaneous; Administration, Oral; Adult; Amphotericin B; Anti-Bacterial Agents; Antibiotic Prophylaxis; APACHE; Case-Control Studies; Colistin; Cross Infection; Drug Resistance, Bacterial; Female; France; Gentamicins; Gram-Negative Bacteria; Gram-Positive Bacteria; Hospitals, University; Humans; Intensive Care Units; Male; Methicillin Resistance; Microbial Sensitivity Tests; Middle Aged; Multiple Trauma; Retrospective Studies; Staphylococcus epidermidis

Topics: Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; Colistin; Cross Infection; Humans; Pneumonia, Bacterial; Respiration, Artificial

We report on an outbreak of colistin-resistant Pseudomonas aeruginosa (CRPA) that occurred in a United Kingdom pediatric cystic fibrosis (CF) unit and involved six children over a period of 5 years. All CRPA-positive children had received aerosolized colistin therapy before first isolation of resistant organisms (mean duration, 3.1 years). Four of the 6 had also received courses of intravenous colistin in the year before the first isolation of CRPA. No impact of CRPA acquisition on respiratory function, clinical condition, or radiological parameters could be demonstrated. Four of the 6 children carried isolates of CRPA indistinguishable on genotyping. Two of these 4 children were sisters. The other 2 were on the same ward together at time of first isolation, and subsequently shared overlapping admissions with one of the sisters. While there is no conclusive evidence for the route of transmission, the frequency of overlapping in-patient admissions between 3 of these patients is suggestive of patient-to-patient transfer in the nosocomial setting.CF clinicians should be aware that colistin resistance can occur in P. aeruginosa, and some of these strains are capable of spread within CF units.

Topics: Anti-Bacterial Agents; Child; Child, Preschool; Colistin; Cross Infection; Cystic Fibrosis; Disease Outbreaks; Drug Resistance, Microbial; Female; Humans; Pseudomonas aeruginosa; Pseudomonas Infections; Time Factors

Stenotrophomonas maltophilia is characterized by intrinsic resistance to a variety of antimicrobials. Therapeutic options are often limited particularly after the emergence of isolates resistant to trimethoprim/sulfamethoxazole. The application of colistin for infections caused by multidrug-resistant Gram-negative pathogens is limited due to its toxicity. In order to evaluate the activity of the interaction of colistin with rifampin or trimethoprim/sulfamethoxazole on S. maltophilia, 24 different isolates resistant to trimethoprim/sulfamethoxazole were in vitro exposed over-time to the combination of 1x and 4 x MIC of colistin with 2 microg/ml of rifampin or 2/38 microg/ml of trimethoprim/sulfamethoxazole. The applied concentrations for rifampin and trimethoprim/sulfamethoxazole reflect their mean serum levels. Synergy of colistin and rifampin was documented after the first two hours of bacterial growth for approximately 60% of isolates and it occurred with both applied concentrations of colistin. The interaction of colistin and rifampin prevented regrowth observed when single colistin was applied. Synergy of colistin and trimethoprim/sulfamethoxazole was mainly found when colistin was applied at a concentration of 4 x MIC involving 41.7% of isolates after 24 h of growth. In the presence of trimethoprim/sulfamethoxazole bacterial regrowth, observed when single colistin was applied, was prevented. It is concluded that growth of multidrug-resistant S. maltophilia is significantly inhibited by the interaction of colistin and rifampin and to a lesser extent of colistin and trimethoprim/sulfamethoxazole. These results merit further study in both the animal model and the clinical setting.

Topics: Anti-Bacterial Agents; Colistin; Colony Count, Microbial; Cross Infection; Drug Resistance, Multiple, Bacterial; Drug Synergism; Gram-Negative Bacterial Infections; Humans; Microbial Sensitivity Tests; Rifampin; Stenotrophomonas maltophilia; Trimethoprim, Sulfamethoxazole Drug Combination

Patients requiring long-term ventilation are at high risk of lower airway infections, generally of endogenous development. Patients on long-term ventilation, in particular via a tracheostomy, may develop tracheobronchitis or pneumonia of exogenous pathogenesis, ie, caused by microorganisms not carried in the oropharynx. The frequency of exogenous colonization or infection has previously been reported to be as high as 33%. A prospective observational cohort study of 2 years was undertaken to evaluate the efficacy of topical antibiotics in the prevention of exogenous colonization or infection of the lower airways. The antibiotic combination of polymyxin E and tobramycin in a 2% paste was applied four times a day on the tracheostoma.. A total of 23 children (median age, 4.1 months; range, 0 to 215 months) were enrolled in the study from September 1, 1996, until August 30, 1998. Surveillance samples of the oropharynx were obtained before tracheostomy and thereafter twice weekly. Diagnostic samples of the lower airways were taken once weekly and on clinical indication.. Fourteen children (61%) had a total of 16 episodes of tracheal colonization or infection with 20 potentially pathogenic microorganisms. Only one child had tracheobronchitis with Streptococcus pneumoniae and Haemophilus influenzae during the 2-year study. Of the 16 colonization episodes, 12 (75%) were of primary endogenous pathogenesis, ie, caused by microorganisms present in the oropharynx at the time of tracheostomy. Community microorganisms including S pneumoniae, H influenzae, Moraxella (Branhamella) catarrhalis, and Staphylococcus aureus were the predominating bacteria. Three patients acquired nosocomial bacteria Pseudomonas aeruginosa and Hafnia alvei in the oropharynx, subsequently followed by secondary colonization of the lower airways. There was one failure of the prophylaxis: one patient (4%) had exogenous colonization with Pseudomonas pickettii.. Topical antibiotics applied to the tracheostoma were found to be effective in reducing the exogenous route of colonization of the lower respiratory tract, compared with clinical experience and the literature. This promising technique requires further evaluation in randomized trials.

Topics: Administration, Topical; Adolescent; Antibiotic Prophylaxis; Bacteriological Techniques; Child; Child, Preschool; Cohort Studies; Colistin; Cross Infection; Drug Therapy, Combination; Female; Humans; Infant; Infant, Newborn; Male; Oropharynx; Pilot Projects; Pneumonia, Bacterial; Prospective Studies; Tobramycin; Tracheostomy; Treatment Outcome

Gram-negative bacilli including multidrug-resistant (MDR) Pseudomonas aeruginosa are responsible for a significant proportion of episodes of nosocomial pneumonia. Since the development of new antibiotics with activity against gram-negative organisms has not kept pace with the increase in prevalence of MDR pathogens, there has been renewed interest in antimicrobial agents that had previously been used but had been abandoned because of toxic side effects. This report describes three patients with nosocomial pneumonia or tracheobronchitis due to multiresistant strains of P. aeruginosa for whom aerosolized colistin proved beneficial as supplemental therapy. Aerosolized colistin merits further consideration as a therapeutic intervention for patients with pulmonary infections due to MDR P. aeruginosa.

Topics: Administration, Inhalation; Aged; Anti-Bacterial Agents; Bronchitis; Colistin; Cross Infection; Drug Resistance, Multiple; Humans; Male; Middle Aged; Pneumonia, Bacterial; Pseudomonas aeruginosa; Pseudomonas Infections; Tracheitis

Topics: Acinetobacter Infections; Adult; Anti-Bacterial Agents; Colistin; Critical Care; Cross Infection; Drug Resistance, Microbial; Drug Resistance, Multiple; Erythromycin; Humans; Klebsiella Infections; Klebsiella pneumoniae; Middle Aged; Patient Isolation; Risk Factors

A prospective cohort study in a neonatal intensive care unit (ICU) was carried out to evaluate whether the incidence of infection in neonates receiving intestinal decolonization was reduced in comparison to those who did not. This study was performed after controling possible confounding infection risk factors. A total of 536 babies were screened in our ICU during the 27-month study period. Neonates were admitted to the ICU for different reasons: low weight, respiratory distress syndrome, acute fetal suffering, surgery, etc. The doctor in charge decided whether the baby should be decolonized or not, so this experimental study was non-random. Thus more of the babies with a greater risk of infection were decolonized more often than the other babies who were not so much at risk. In this study, babies were classified by type of decolonization given: a well-performed Selective Intestinal Decolonization (SID) was done (early and with three oral drugs: E polymyxin, tobramycin and nystatin): 10.8% of the babies; Incorrect SID (was begun late and/or less than three drugs were used): 16.7% of the babies; and Without SID (72.9%). Total nosocomial infection (NI) was 11.2%, catheter-associated sepsis was 42% of the total NI. When the NI incidence was directly compared among groups, it was lower in the group without SID, but infants with decolonization initially had more infection risk factor than the first group. For this reason, multiple logistic regression was used in order to stratify factors by infection probability, and correcting the existing bias.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Chi-Square Distribution; Cohort Studies; Colistin; Confounding Factors, Epidemiologic; Cross Infection; Drug Therapy, Combination; Humans; Incidence; Infant, Newborn; Intensive Care Units, Neonatal; Intestines; Logistic Models; Multivariate Analysis; Nystatin; Prospective Studies; Spain; Tobramycin

The objective of the present work was to assess the possible mechanisms of the poor efficiency of selective decontamination of the digestive tract (SDD) in medical and surgical intensive care unit (ICU) patients. Sixty-four consecutive mechanically ventilated patients received gut decontamination with polymixin E, gentamicin and amphotericin B via a nasogastric tube and were assessed for oropharyngeal, gastric and fecal colonization and for the presence of each antibiotic in the stomach and feces. A decrease in fecal colonization with Escherichia coli was observed over 20 days but not with other gram-negative bacteria or gram-positive cocci. Fifteen and 26% of the fecal colonizing gram-negative bacteria were resistant to polymixin E and gentamicin, respectively, at admission. These proportions increased to up to 50% after 16 days of treatment. Although 50% of staphylococci were initially sensitive to gentamicin, all strains were resistant to this drug after four days of SDD. Both antibiotics were found in concentrations of less than 20 micrograms/g in 11 of 38 stools. Of these 38 stools, nine were not contaminated, 20 were colonized with resistant bacteria and 16 with strains sensitive to one antibiotic present in the stool. Therefore, the poor efficiency of gut decontamination observed was probably due to the great proportion of resistant strains on admission of the patients, to the selection of such resistant strains with SDD, to poor intestinal transit of the antibiotics, and to inactivation of the drugs by the feces. These results support stringent monitoring of fecal colonization in patients undergoing SDD in order to detect the fecal carriage of gram-positive and multiresistant gram-negative bacteria.

Topics: Adult; Aged; Amphotericin B; Colistin; Cross Infection; Digestive System; Drug Resistance, Microbial; Drug Therapy, Combination; Escherichia coli; Feces; Female; Gentamicins; Humans; Intensive Care Units; Male; Middle Aged; Treatment Failure

To evaluate the efficiency of intratracheal colistin in preventing nosocomial bronchopneumonia (BPN) in the critically ill.. Study evaluating the clinical incidence of nosocomial BPN in 2 groups of critically ill patients who receive or did not receive intratracheal colistin. BPN was assessed clinically in survivors and histologically in non-survivors.. A 14-bed surgical intensive care unit.. 598 consecutive critically ill patients were studied during a prospective non-randomized study over a 40-month period.. 251 patients--31 non-survivors and 220 survivors--did not receive intratracheal colistin and 347-42 non-survivors and 305 survivors--received intratracheal colistin for a 2-week period (1,600,000 units per 24 h).. The incidence of nosocomial BPN was evaluated clinically in survivors, using repeated protected minibronchoalveolar lavages, and histologically in non-survivors via an immediate postmortem pneumonectomy (histologic and semi-quantitative bacteriologic analysis of one lung). The clinical incidence of nosocomial BPN was of 37% in coli (-) survivors and of 27% in coli (+) survivors (p < 0.01). This result was histologically confirmed in non-survivors, where the incidence of histologic BPN was of 61% in coli (-) patients and of 36% in coli (+) patients (p < 0.001). Emergence of BPN due to colistin-resistant micro-organisms was not observed. Because colistin was successful in preventing Gram-negative BPN and did not change the absolute number of Gram-positive BPN, the proportion of BPN caused by staphylococcus species was higher in group coli (+) patients (33% vs 16%). Mortality was not significantly influenced by the administration of colistin.. This study suggests that the administration of intratracheal colistin during a 2-week period significantly reduces the incidence of Gram-negative BPN without creating an increasing number of BPN due to colistin-resistant micro-organisms.

Topics: Aged; Bronchoalveolar Lavage Fluid; Colistin; Critical Illness; Cross Infection; Drug Evaluation; Drug Resistance, Microbial; Female; Gram-Negative Bacterial Infections; Humans; Incidence; Instillation, Drug; Intubation, Intratracheal; Male; Microbial Sensitivity Tests; Middle Aged; Pneumonectomy; Pneumonia; Prospective Studies; Respiration, Artificial; Survival Rate

to evaluate the effect of the prolonged systematic use of topical SDD (tobramycin 80 mg, polymyxin E 100 mg, amphotericin B 500 mg) on ICU ecology as expressed by changes in tracheal colonization and bacterial resistances.. Prospective microbiological survey.. Polyvalent ICU of a 2000 beds general hospital.. Data concerning bacterial strains isolated from the tracheo-bronchial aspirates of all the patients admitted to a polyvalent ICU over 3 consecutive periods of 12 months ('88, '89, '90) were prospectively entered in a database and subsequently analyzed. During a 3-year period 502 patients required artificial ventilation for more than 72 h and 332 of them ('89 and '90) were treated with SDD. All samples collected within 72 h from ICU admission were excluded as well as duplicate samples from the same patients.. All the patients admitted to the ICU in '89 and '90 and submitted to artificial ventilation for at least 24 h were routinely treated with topical SDD without i.v. antibiotic prophylaxis; in '88 SDD was not employed.. Criteria for collecting sputum samples and microbiological procedures remained unchanged throughout the study-time. Positive sputum were significantly less in '89 (80.8% versus 92.3% p < 0.001) and this was due to a very sharp decrease in the isolation of Gram-negative strains from 43-28% (-64% p < 0.0001) involving both: Enterobacteriaceae (-45%) and Pseudomonaceae (-77%). In 1990; however, a new increase in Gram negative was observed, although the overall amount of Gram-negative was still 49% lower in '90 if compared to '88 (p < 0.0001). A dramatic increase in Pseudomonas isolation was the only factor responsible for the "rebound" observed. An increasing percentage of Pseudomonas developed a resistance towards tobramycin and only 45% of Pseudomonas strains turned out to be sensible to tobramycin in '90 against 79% in '88. A similar trend was registered for all aminoglycosides with the exception of amikacin. Gram-positive colonizations tended to increase (+63%) (p < 0.0001) and this was mainly due to Coagulase negative Staphylococci (+290% p < 0.0001) and S. pneumoniae, whereas S. aureus isolations decreased (-18%) but not significantly.. Our data suggest that the prolonged use of SDD is associated with dramatic changes in ICU ecology: the incidence of Gram negative colonization is significantly diminished by SDD whereas Gram positive tend to increase. Pseudomonas developed an increasing resistance towards tobramycin one of the components of the SDD formula we used.

Topics: Administration, Oral; Administration, Topical; Amphotericin B; Bronchi; Colistin; Colony Count, Microbial; Cross Infection; Drug Resistance, Microbial; Drug Therapy, Combination; Gram-Negative Bacteria; Gram-Positive Bacteria; Humans; Incidence; Infection Control; Intensive Care Units; Intubation, Gastrointestinal; Pneumonia; Respiration, Artificial; Sputum; Tobramycin; Trachea

Topics: Aged; Amphotericin B; Colistin; Cross Infection; Digestive System; Drug Resistance, Microbial; Escherichia coli; Gentamicins; Gram-Negative Aerobic Bacteria; Gram-Positive Cocci; Humans; Intensive Care Units; Middle Aged

An outbreak caused by a Klebsiella aerogenes resistant to ceftazidime, cefuroxime, cefotaxime, ampicillin and piperacillin and sensitive to aminoglycosides, imipenem and temocillin occurred in a teaching hospital's busy multi-disciplinary Intensive Care Unit over a 3-month period. Four patients had bacteraemia and a further four were colonized. Traditional infection control measures failed to eradicate the outbreak. The introduction of a selective gastrointestinal decontamination regimen consisting of tobramycin, amphotericin and colistin as a gel to the oropharynx, nose and rectum and a suspension via a nasogastric tube resulted in rapid disappearance of the outbreak strain with no new isolates being detected clinically or in surveillance specimens over an 8-week period.

Topics: Amphotericin B; Colistin; Cross Infection; Disease Outbreaks; Gastrointestinal Diseases; Hospitals, Teaching; Humans; Intensive Care Units; Klebsiella Infections; Klebsiella pneumoniae; Microbial Sensitivity Tests; Tobramycin

In a Tunisian hospital 27 babies, including 12 who were premature, in a single intensive care unit suffered acute gastroenteritis in the period from January to May 1988. The mean age at the onset of gastroenteritis was 8.4 days; nine babies died. Salmonella wien was isolated from stools (all babies) and blood (4 babies). It was also isolated from the stools of one nurse and from a mattress. Twelve of the babies had received cefotaxime, which was successfully replaced by oral colimycin. The outbreak was stopped by the implementation of infection control measures. All isolates of Salmonella wien were of the same biotype, and had the same antibiotic resistance pattern (third generation cephalosporins, monobactams, aminoglycosides, chloramphenicol, trimethoprim and sulphonamides) and plasmid DNA restriction pattern. The isolates were all susceptible to a combination of cefotaxime and clavulanic acid (a beta-lactamase inhibitor), which displayed synergy, suggesting the presence of a beta-lactamase (geometric mean MICs 11.24 micrograms/ml for cefotaxime alone and 0.24 micrograms/ml in combination with 0.1 micrograms/ml potassium clavulanate). All isolates produced TEM-1 and SHV-2 beta-lactamase which was not transferable to Escherichia coli by conjugation. The presence of the SHV-2 enzyme in Salmonella wien may allow it to adapt to newer beta-lactams which is a cause for concern in this hospital.

Topics: Acute Disease; beta-Lactamases; Cefotaxime; Clavulanic Acid; Clavulanic Acids; Colistin; Cross Infection; Disease Outbreaks; Drug Resistance, Microbial; Drug Synergism; Feces; Gastroenteritis; Humans; Infant, Newborn; Infant, Premature; Infant, Premature, Diseases; Intensive Care Units, Neonatal; Microbial Sensitivity Tests; Salmonella; Salmonella Infections; Tunisia

Topics: Carbenicillin; Colistin; Cross Infection; Gentamicins; Hospitals, University; Humans; Nigeria; Penicillin Resistance; Pseudomonas aeruginosa; Pseudomonas Infections

An epidemic caused by Serratia marcescens occurred in intensive care unit of the Children's clinic in Essen, with three deaths. Although there was good sensitivity of the strain to gentamicin in vitro, there was no noticeable clinical improvement when it was administered. But cotrimoxazole, given systemically and locally, and colistin locally cured the disease.

Topics: Colistin; Cross Infection; Disease Outbreaks; Enterobacteriaceae Infections; Gentamicins; Germany, West; Humans; Infant, Newborn; Infant, Newborn, Diseases; Infant, Premature, Diseases; Intensive Care Units; Sepsis; Serratia marcescens; Sulfamethoxazole; Trimethoprim

Topics: Aged; Amikacin; Colistin; Cross Infection; Disease Outbreaks; Drug Administration Schedule; Drug Resistance, Microbial; Female; Humans; Injections, Intramuscular; Injections, Intravenous; Kanamycin; Klebsiella Infections; Klebsiella pneumoniae; Male; Middle Aged; Urinary Tract Infections

The current circumstances associated with Pseudomonas aeruginosa bacteremia are reviewed in 108 episodes to assess the impact of new antimicrobial drugs on this infection. Since 1961, Pseudomonas bacteremia has apparently become more frequent with proportional increases in middle-aged patients. The respiratory tract has become the major source of infection. Clinical features are not characteristic, but infected patients are almost uniformly severely ill before blood stream invasion occurs. The use of gentamicin, carbenicillin and colistin has not changed the outcome of Pseudomonas bacteremia. Although better than no antimicrobial treatment, these drugs cannot be shown to be superior to any other available antibiotics. A reassessment is needed to evaluate the relationship between the in vitro action and the effectiveness of antibiotics in the treatment of Pseudomonas infection and the use of gentamicin, carbenicillin and colistin in these bacteremias. In view of the poor results with antibiotics, investigation into immunologic prophylaxis and therapy is needed. At the present time, control of the patients' underlying disease contributes most towards assuring survival with Pseudomonas bacteremia.

Topics: Anti-Bacterial Agents; Carbenicillin; Chronic Disease; Colistin; Cross Infection; Gentamicins; Humans; Infant; Infant, Newborn; Infant, Newborn, Diseases; Neoplasms; Penicillin Resistance; Pseudomonas aeruginosa; Pseudomonas Infections; Sepsis

35 patients were secondarily infected in our hospital with a strain of A. calcoaceticus resistant to the usual antibiotics and sulfonamides, but sensitive to colimycin. The epidemic lasted 118 days and is not yet finished. Each of the infected patients had a severe surgical or medical illness, underwent operations, trachetomy, etc. and was treated with antibiotics. A. calcoaceticus persisted alone or was associated with other bacteria from 1 to 46 days, in specimens (sputum, etc. or in blood) sometimes until death. It is not pathogenic for rabbits and mice; its pathogenicity in man is discussed in the text. The epidemic strain was not harboured by 15 doctors, students or nurses, nor present on 147 objects in the vicinity of the patients, but was found in a bottle of aqueous 1% eosin solution in the room of an infected child. Experiments show that A. calcoaceticus is not killed by a 1% eosin solution, and freely multiplies in broth containing 0,5% eosin. It is easy to identify the first case and chronology of the epidemic, but it is less easy to identify each time the means of propagation. Usually, infected patients seem to be the source of further infection. Does eosin paly more than an occasional role? Were the germs transported by dust? This not very disturbing epidemic suggests that less pathogenic germs may still cause unsuspected hospital epidemics.

Topics: Acinetobacter; Adolescent; Adult; Aged; Alcaligenes; Anti-Bacterial Agents; Bacterial Infections; Bronchopneumonia; Child; Child, Preschool; Colistin; Cross Infection; Disease Outbreaks; Drug Resistance, Microbial; Female; Humans; Infant; Male; Meningitis; Microbial Sensitivity Tests; Middle Aged; Pseudomonas aeruginosa

Like in other operative disciplines also in orthopedic surgery we can see an icrease of infections with gramnegative bacterial like ps. pyocyanea. Gentamicin is in general very effective against these infections. There are following indications for the use of Gentamicin in orthopedic surgery: 1. Parenteral administration only is indicated if there is no other less toxic antibiotic. If it is used a high dosage is necessary because the bone levels which we investigated were very low. Side effects have to be observed. 2. For local therapy Gentamicin is used in the suction and perfusion system in addition to a systemic therapy with Penicillin, Ampicillin or Cephalosporin. Gentamicin can also be used for the wound perfusion. 3. Added to bone cement Gentamicin should only be taken, when an infected total hip is exchanged or if a hospitalism with ps. pyocyanea is known- The administration of Gentamicin is less indicated : 1. Asthe only antibiotic for parenteral therapy in bone infection. 2. Added to bone cement for a general prophylaxis in all endoprosthetic operations.

Topics: Administration, Topical; Ampicillin; Bone and Bones; Bone Cements; Carbenicillin; Cephalosporins; Colistin; Cross Infection; Drug Therapy, Combination; Gentamicins; Humans; Orthopedics; Penicillins; Surgical Wound Infection; Wound Infection

Topics: Administration, Topical; Animals; Burns; Colistin; Cross Infection; Disease Models, Animal; Drug Resistance, Microbial; Ecthyma; Enterobacteriaceae; gamma-Globulins; Gentamicins; Humans; Pneumonia; Providencia; Pseudomonas; Pseudomonas Infections; Rats; Sepsis; Simplexvirus; Sulfonamides; Surgical Wound Infection; Thrombophlebitis; Time Factors

Topics: Burns; Carbenicillin; Colistin; Cross Infection; Germany, West; Humans; Patient Care Planning; Penicillin Resistance; Pseudomonas aeruginosa; Pseudomonas Infections; Serotyping; Water Microbiology; Wound Infection

Topics: Adult; Ampicillin; Bacteria; Carbenicillin; Cephaloridine; Chloramphenicol; Colistin; Cross Infection; Delivery, Obstetric; Escherichia coli; Feces; Female; Gentamicins; Humans; Immunity, Maternally-Acquired; Infant, Newborn; Intensive Care Units; Kanamycin; Klebsiella; Male; Microbial Sensitivity Tests; Nalidixic Acid; Nitrofurantoin; Penicillin Resistance; Proteus; Pseudomonas aeruginosa; Serotyping; Streptomycin; Tetracycline

Topics: Adult; Anti-Bacterial Agents; Colistin; Corneal Ulcer; Cross Infection; Eye Foreign Bodies; Gentamicins; Humans; Male; Middle Aged; Polymyxins; Pseudomonas aeruginosa; Pseudomonas Infections

During a serious epidemic of chest and urinary infections due to Klebsiella aerogenes in a neurosurgical unit, several patients developed klebsiella meningitis after trauma or surgery. Despite all attempts to control the epidemic and treat the meningitis with antibiotics, eight of the nine patients died. It was not until all antibiotics used to treat respiratory and urinary infections had been totally withdrawn that no further patients developed klebsiella meningitis.

Topics: Adult; Ampicillin; Child; Child, Preschool; Cloxacillin; Colistin; Cross Infection; Disease Outbreaks; Female; Gentamicins; Humans; Injections, Spinal; Klebsiella Infections; Male; Meningitis; Microbial Sensitivity Tests; Middle Aged; Penicillin Resistance; Scotland; Surgical Wound Infection

Topics: Ampicillin; Cephalothin; Chloramphenicol; Colistin; Cross Infection; Gentamicins; Humans; Kanamycin; Klebsiella Infections; Lung; Penicillin Resistance; Prognosis; Sepsis; Skin; Streptomycin; Sulfonamides; Surgical Wound Infection; Tetracycline; Urinary Tract

Topics: Adolescent; Adult; Age Factors; Aged; Colistin; Cross Infection; Escherichia coli Infections; Female; Fever; Humans; Kanamycin; Klebsiella Infections; Leukocyte Count; Male; Microbial Sensitivity Tests; Middle Aged; Nitrogen; Penicillins; Proteus Infections; Pseudomonas Infections; Retrospective Studies; Sepsis; Sex Factors; Shock; Uremia

Topics: Anti-Bacterial Agents; Antibodies; Colistin; Cross Infection; Disease Outbreaks; Drug Resistance, Microbial; Escherichia coli Infections; Gastroenteritis; Hospital Design and Construction; Humans; Infant; Infant, Newborn; Patient Isolators

Topics: Anti-Bacterial Agents; Carbenicillin; Colistin; Cross Infection; Gentamicins; Humans; Kanamycin; Microbial Sensitivity Tests; Moraxella; Penicillin Resistance

Topics: Adolescent; Adult; Aged; Cardiac Output; Cephalothin; Child; Child, Preschool; Colistin; Cross Infection; Female; Hemorrhage; Humans; Immunosuppression Therapy; Kanamycin; Lung; Male; Middle Aged; Neoplasms; Oxygen Consumption; Pancreatitis; Pyelonephritis; Retrospective Studies; Sepsis; Shock, Septic; Thromboembolism

Topics: Anti-Bacterial Agents; Colistin; Cross Infection; Disease Outbreaks; Humans; Intensive Care Units; Klebsiella; Klebsiella Infections; Meningitis; Neurosurgery; Respiratory Tract Infections; Sputum; Urinary Tract Infections

Topics: Ampicillin; Cloxacillin; Colistin; Cross Infection; Humans; Intensive Care Units; Klebsiella Infections; Lung Diseases; Neurosurgery; Penicillin Resistance; Urinary Tract Infections

Topics: Anti-Bacterial Agents; Colistin; Cross Infection; Drug Resistance, Microbial; Gentamicins; Humans; Otorhinolaryngologic Diseases; Polymyxins; Pseudomonas aeruginosa; Pseudomonas Infections; Sterilization

Topics: Acute Kidney Injury; Adolescent; Adult; Aged; Air Microbiology; Ampicillin; Ascitic Fluid; Bacteriocins; Benzalkonium Compounds; Catheterization; Cephaloridine; Chloramphenicol; Colistin; Cross Infection; Ethylene Oxide; Filtration; Gentamicins; Humans; Kanamycin; Lysogeny; Middle Aged; Nalidixic Acid; Peritoneal Dialysis; Pseudomonas aeruginosa; Pseudomonas Infections; Renal Dialysis; Sterilization; Streptomycin; Tetracycline; Ultraviolet Rays; Urinary Tract Infections

Topics: Colistin; Cross Infection; Escherichia coli; Escherichia coli Infections; Humans; Infant, Newborn; Infant, Premature, Diseases; Italy

Topics: Ampicillin; Chloramphenicol; Colistin; Cross Infection; Enterobacter; Enterobacteriaceae; Enterobacteriaceae Infections; Epidemiologic Methods; Escherichia coli; Housekeeping, Hospital; Humans; Kanamycin; Methods; Otorhinolaryngologic Diseases; Proteus; Proteus Infections; Pseudomonas aeruginosa; Pseudomonas Infections; Tetracycline

Topics: Chloramphenicol; Colistin; Cross Infection; Disease Outbreaks; Humans; Infant; Infant, Newborn; Infant, Newborn, Diseases; Paris; Salmonella Infections

Topics: Colistin; Cross Infection; Disease Outbreaks; Female; France; Humans; Infant, Newborn; Infant, Premature, Diseases; Male; Polymyxins; Pseudomonas aeruginosa; Pseudomonas Infections

Topics: Adult; Cephalothin; Child; Colistin; Cross Infection; Enterobacter; Enterobacteriaceae Infections; Gentamicins; Germany, West; Humans; Infant, Newborn; Middle Aged; Penicillin Resistance; Penicillins; Postoperative Complications; Sepsis

Topics: Adrenal Cortex Hormones; Bacillus; Colistin; Cross Infection; Drug Therapy; gamma-Globulins; Humans; Lung Diseases; Polymyxins; Postoperative Complications; Pseudomonas aeruginosa; Pseudomonas Infections; Resuscitation; Sepsis

Topics: Anti-Bacterial Agents; Child; Chloramphenicol; Colistin; Cross Infection; Drug Resistance; Drug Resistance, Microbial; Escherichia coli; Escherichia coli Infections; Framycetin; Humans; Kanamycin; Neomycin; Statistics as Topic; Tetracycline

Topics: Anti-Bacterial Agents; Colistin; Cross Infection; Diarrhea, Infantile; Drug Resistance, Microbial; Escherichia coli Infections; Female; Furazolidone; Germany, West; Humans; Infant, Newborn; Infant, Premature, Diseases; Polymyxins; Pregnancy; Statistics as Topic

Topics: Colistin; Cross Infection; Diarrhea; Diarrhea, Infantile; Disease Outbreaks; Drug Resistance; Drug Resistance, Microbial; Escherichia coli; Escherichia coli Infections; Feces; Humans; Neomycin; Nitrofurantoin; Polymyxins; Propiophenones; Streptomycin; Sulfathiazoles

Topics: Amphotericin B; Animals; Colistin; Cross Infection; Enterovirus C, Human; Epidemiology; Feces; Haplorhini; Humans; Infant; Penicillins; Poliomyelitis; Poliovirus; Serologic Tests; Streptomycin; Virus Cultivation

Topics: Alcoholism; Colistin; Cross Infection; Cystoscopy; Humans; Lung Abscess; Nephritis; Nephritis, Interstitial; Pseudomonas aeruginosa; Pseudomonas Infections; Streptomycin; Urinary Catheterization

Topics: Colistin; Cross Infection; Humans; Infant; Infant, Newborn; Infant, Premature; Infant, Premature, Diseases; Kanamycin; Klebsiella; Klebsiella Infections; Klebsiella pneumoniae; Meningitis; Ophthalmology; Oxytetracycline; Polymyxins