epiglucan and Opportunistic-Infections

Topics: Aged; beta-Glucans; Biomarkers; Biopsy; Dermatomycoses; Humans; Leg Ulcer; Lung Transplantation; Male; Opportunistic Infections; Postoperative Complications; Pyoderma Gangrenosum; Scedosporium; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization

Infections caused by filamentous fungi represent a major burden in the ICU. Invasive aspergillosis is emerging in non-neutropenic individuals with predisposing conditions, e.g. corticosteroid treatment, chronic obstructive pulmonary disease, liver cirrhosis, solid organ cancer, HIV infection and transplantation. Diagnosis is challenging because the signs and symptoms are non-specific, and initiation of additional diagnostic examinations is often delayed because clinical suspicion is low. Isolation of an Aspergillus species from the respiratory tract in critically ill patients, and tests such as serum galactomannan, bronchoalveolar lavage 1-3-β-d-glucan and specific PCR should be interpreted with caution. ICU patients should start adequate antifungal therapy upon suspicion of invasive aspergillosis, without awaiting definitive proof. Voriconazole, and now isavuconazole, are the drugs of choice. Mucormycosis is a rare, but increasingly prevalent disease that occurs mainly in patients with uncontrolled diabetes mellitus, immunocompromised individuals or previously healthy patients with open wounds contaminated with Mucorales. A high proportion of cases are diagnosed in the ICU. Rapidly progressing necrotizing lesions in the rhino-sinusal area, the lungs or skin and soft tissues are the characteristic presentation. Confirmation of diagnosis is based on demonstration of tissue invasion by non-septate hyphae, and by new promising molecular techniques. Control of underlying predisposing conditions, rapid surgical resection and administration of liposomal amphotericin B are the main therapeutic actions, but new agents such as isavuconazole are a promising alternative. Patients with mucormycosis receive a substantial part of their care in ICUs and, despite advances in diagnosis and treatment, mortality remains very high.

Topics: Antifungal Agents; Aspergillosis; Aspergillus; beta-Glucans; Critical Illness; Galactose; Humans; Immunocompromised Host; Intensive Care Units; Invasive Fungal Infections; Lung Diseases, Fungal; Mannans; Mucor; Mucormycosis; Nitriles; Opportunistic Infections; Pyridines; Respiratory System; Triazoles; Voriconazole

Despite the availability of newer antifungal drugs, outcomes for patients with invasive fungal infections (IFIs) continue to be poor, in large part due to delayed diagnosis and initiation of appropriate antifungal therapy. Standard histopathologic diagnostic techniques are often untenable in at-risk patients, and culture-based diagnostics typically are too insensitive or nonspecific, or provide results after too long a delay for optimal IFI management. Newer surrogate markers of IFIs with improved sensitivity and specificity are needed to enable earlier diagnosis and, ideally, to provide prognostic information and/or permit therapeutic monitoring. Surrogate assays should also be accessible and easy to implement in the hospital. Several nonculture-based assays of newer surrogates are making their way into the medical setting or are currently under investigation. These new or up-and-coming surrogates include antigens/antibodies (mannan and antimannan antibodies) or fungal metabolites (d-arabinitol) for detection of invasive candidiasis, the Aspergillus cell wall component galactomannan used to detect invasive aspergillosis, or the fungal cell wall component and panfungal marker β-glucan. In addition, progress continues with use of polymerase chain reaction- or other nucleic acid- or molecular-based assays for diagnosis of either specific or generic IFIs, although the various methods must be better standardized before any of these approaches can be more fully implemented into the medical setting. Investigators are also beginning to explore the possibility of combining newer surrogate markers with each other or with more standard diagnostic approaches to improve sensitivity, specificity, and capacity for earlier diagnosis, at a time when fungal burden is still relatively low and more responsive to antifungal therapy.

Topics: Adult; Amphotericin B; Antifungal Agents; Antineoplastic Agents; beta-Glucans; Biomarkers; Female; Fusariosis; Humans; Immunocompromised Host; Leukemia, Myeloid, Acute; Meta-Analysis as Topic; Mycoses; Opportunistic Infections; Polymerase Chain Reaction

A growing population of immunosuppressed patients has resulted in increasingly frequent diagnoses of invasive fungal infections, including those caused by unusual yeasts. The incidence of non-albicans species of Candida is increasing compared with that of Candida albicans, and several species, such as Candida glabrata and Candida krusei, may be resistant to azole antifungal therapy. Trichosporon species are the second most common cause of fungaemia in patients with haematological malignant disease and are characterised by resistance to amphotericin and echinocandins and poor prognosis. Rhodotorula species belong to the family Cryptococcaceae, and are a cause of catheter-related fungaemia, sepsis, and invasive disease in severely immunosuppressed patients. An increasing number of sporadic cases of invasive fungal infections by non-neoformans cryptococci have been reported in immunocompromised hosts, especially for patients with advanced HIV infection or cancer who are undergoing transplant. Other uncommon yeasts that can cause invasive disease in severely immunosuppressed patients include Geotrichum, Hansenula, Malassezia, and Saccharomyces. Host immune status is a crucial determinant of the type of invasive fungal infection a patient is at risk for. Diagnosis can be challenging and relies heavily on traditional cultures of blood and other sterile sites, although serum (1,3)-β-D-glucan testing might have an adjunctive role. Although rare yeasts are emerging as opportunistic human pathogens, diagnosis remains challenging and treatment suboptimal.

Topics: beta-Glucans; Clinical Laboratory Techniques; Communicable Diseases, Emerging; Fungi; Humans; Immunocompromised Host; Incidence; Mycology; Mycoses; Opportunistic Infections; Proteoglycans

The increasing number of patient populations at high risk of opportunistic infections has highlighted the need for the improvement in antifungal treatments. Due to the limited number of currently available antifungal drugs and the concerns for possible prevalence of resistant strains, drugs with a new mechanism of action are most desirable.. Although the cell wall is considered to be one of the ideal targets for antifungal drugs, insufficient information on the enzymes involved in its construction has restricted the discovery of new inhibitors. This review introduces the recent discovery of the inhibitors of β-1,6-glucan, one of the essential components of the yeast cell wall.. The readers will gain the strategy to obtain the β-1,6-glucan synthesis inhibitors, their mechanisms of actions, and antifungal activities in vitro as well as in vivo.. The β-1,6-glucan inhibitors are considered to be promising candidates for new antifungal drugs which could give valuable options in a clinical setting, although their usage may be limited because of their fungistatic action and limited spectrum. Additionally, they can be useful tools in the study on β-1,6-glucan synthesis and the virulence of Candida species.

Topics: Antifungal Agents; beta-Glucans; Cell Wall; Fungi; Humans; Mycoses; Opportunistic Infections

In the last few years, major advances in the treatment of transplant recipients, with hemato-oncological diseases or admitted to the intensive care unit, has been accompanied by an increase in classical fungal infections and by the emergence of uncommon fungal infections. Despite the development of new diagnostic techniques such as galactomannan detection and the availability of new antifungal agents, these opportunistic infections continue to pose a diagnostic challenge, prolong length of hospital stay, and increase costs. In addition, mortality from these infections is high. The present chapter provides a brief review of the epidemiology of these infections, diagnostic advances, and the new antifungal agents that have been developed in the last few years.

Topics: Anidulafungin; Antifungal Agents; Aspergillosis; beta-Glucans; Candidiasis; Clinical Trials as Topic; Critical Care; Diabetes Complications; Disease Susceptibility; Echinocandins; Fungemia; Galactose; Hematologic Diseases; Humans; Immunocompromised Host; Mannans; Meta-Analysis as Topic; Mycoses; Neoplasms; Opportunistic Infections

During recent years, a rising incidence of invasive pulmonary aspergillosis (IPA) in non-neutropenic critically ill patients has been reported. Critically ill patients are prone to develop disturbances in immunoregulation during their stay in the ICU, which render them more vulnerable for fungal infections. Risk factors such as chronic obstructive pulmonary disease (COPD), prolonged use of steroids, advanced liver disease, chronic renal replacement therapy, near-drowning and diabetes mellitus have been described. Diagnosis of IPA may be difficult and obtaining histo- or cytopathological demonstration of the fungus in order to meet the gold standard for IPA is not always feasible in these patients. Laboratory markers used as a non-invasive diagnostic tool, such as the galactomannan antigen test (GM), 1,3-beta-glucan, and Aspergillus PCR, show varying results. Antifungal therapy might be considered in patients with persistent pulmonary infection who exhibit risk factors together with positive cultures or sequentially positive GM and Aspergillus PCR in serum, in whom voriconazole is the drug of choice. The benefit of combination antifungal therapy lacks sufficient evidence so far, but this treatment might be considered in patients with breakthrough infections or refractory disease.

Topics: Antifungal Agents; Antigens, Fungal; Aspergillosis; Aspergillus; beta-Glucans; Critical Illness; DNA, Fungal; Drug Therapy, Combination; Galactose; Humans; Intensive Care Units; Lung Diseases, Fungal; Mannans; Opportunistic Infections; Polymerase Chain Reaction; Risk Factors

Coronavirus disease 2019 or COVID-19 is a new infectious disease responsible for potentially severe respiratory impairment associated with initial immunosuppression. Similarly to influenza, several authors have described a higher risk of fungal infection after COVID-19, in particular for invasive pulmonary aspergillosis. The main objective here is to define the prevalence of invasive pulmonary aspergillosis (IPA) in a cohort of COVID-19 patients with moderate to severe acute respiratory disease syndrome (ARDS).. We conducted a large monocentric retrospective study investigating all the ventilated COVID-19 patients with ARDS hospitalized at Valenciennes' general hospital, France, between March 15, 2020 and April 30, 2020. In the center a systematic IPA screening strategy was carried out for all ARDS patients, with weekly tests of serum galactomannan and beta-D-glucan. Bronchoalveolar lavage with culture and chest CT scan were performed when the serum assays were positives.. A total of 54 patients were studied. Their median age was 65 years, and 37 of the patients (71%) were male. Two patients had chronic immunosuppression and among all the patients, only 2 non-immunocompromised presented a putative IPA during their stay.. The prevalence of IPA in this cohort of COVID-19 patients (3.7%) is not higher than what is described in the other ARDS populations in the literature. These results are however different from the previous publications on COVID-19 patients and must therefore be confirmed by larger and multicentric studies.

Topics: Adult; Aged; Aged, 80 and over; beta-Glucans; Biomarkers; Comorbidity; COVID-19; Critical Illness; Female; France; Galactose; Hospitals, General; Humans; Immunocompromised Host; Intensive Care Units; Invasive Pulmonary Aspergillosis; Male; Mannans; Middle Aged; Opportunistic Infections; Respiration, Artificial; Respiratory Distress Syndrome; Retrospective Studies; Risk Factors

Acremonium is an emerging fungal pathogen causing severe infections. We evaluated the virulence of three clinically relevant species within the genus, i.e., Acremonium kiliense (currently Sarocladium kiliense), Acremonium sclerotigenum-A. egyptiacum complex and Acremonium implicatum in a murine model of disseminated infection. Both immunocompetent and immunosuppresssed mice were infected with two inocula concentrations (2 × 10(6) and 2 × 10(8) conidia/animal) of two strains of each species. Tissue burden, mortality rate, histopathology and levels of (1→3)-β-D-glucan were used as virulence markers. None of the species of Acremonium tested was able to cause infection in immunocompetent mice. Conversely, severe infections were produced in immunocompromised mice, the spleen being the most affected organ. In general, the virulence of the Acremonium species tested was low, S. kiliense being the most virulent species.

Topics: Acremonium; Animal Structures; Animals; beta-Glucans; Colony Count, Microbial; Communicable Diseases, Emerging; Disease Models, Animal; Histocytochemistry; Humans; Male; Mice; Microscopy; Mycoses; Opportunistic Infections; Proteoglycans; Survival Analysis; Virulence

Chronic granulomatous disease (CGD) is a primary immunodeficiency characterized by recurrent infections and a dysregulated inflammatory response. Infection-triggered hemophagocytic lymphohistiocytosis (HLH), which manifests itself as pathologic hyperactive inflammation, has been observed in subjects with CGD. However, there have been no reports of HLH as the initial presentation with subsequent diagnosis of CGD. Furthermore, the primary therapeutic strategy for HLH focuses on immunosuppressive therapies, which limits immune-mediated tissue damage. With immunodeficiency, this therapeutic strategy may worsen the outcome. This article discusses an 8-week-old Hispanic male who presented with fever of unknown origin. The initial diagnostic evaluation demonstrated pathologic hyperactive inflammation, meeting the HLH-2004 diagnostic criteria without an identified infectious etiology. Immunosuppressive therapy was initiated, with subsequent disseminated candida septic shock and sepsis-induced multisystem organ failure. Additional evaluations ultimately established the diagnosis of CGD. We transitioned to an immune-enhancing strategy with granulocyte and immunoglobulin infusions, and intensified antifungal therapies. These interventions ultimately led to the clearance of the fungal infection and the resolution of the hyperactive inflammatory state. This case represents the first reported case of HLH as the presenting finding leading to the subsequent diagnosis of CGD. It serves as a reminder that both immunodeficiency and inflammatory disorders may share features of pathologic hyperactive inflammation and highlights the conundrum that clinicians face when treating HLH in the setting of an unresolved infection. In this case report, we demonstrate that immune-enhancing therapies may aid in the control and the clearance of the infection, thus paradoxically decreasing the pathologic hyperactive inflammatory response.

Topics: beta-Glucans; Combined Modality Therapy; Diagnosis, Differential; Disease Progression; DNA Mutational Analysis; Fever of Unknown Origin; Fungemia; Granulocytes; Granulomatous Disease, Chronic; Humans; Immunization, Passive; Immunosuppressive Agents; Infant; Interferon-gamma; Lymphohistiocytosis, Hemophagocytic; Male; Membrane Glycoproteins; NADPH Oxidase 2; NADPH Oxidases; Opportunistic Infections; Proteoglycans

The number of patients with non-HIV Pneumocystis pneumonia (PCP) is increasing with widespread immunosuppressive treatment. We investigated the clinical characteristics of non-HIV PCP and its association with microbiological genotypes.. Between January 2005 and March 2010, all patients in 2 university hospitals who had been diagnosed with PCP by PCR were enrolled in this study. Retrospective chart review of patients, microbiological genotypes, and association with 30-day mortality were examined.. Of the 82 adult patients investigated, 50 patients (61%) had inflammatory diseases, 17 (21%) had solid malignancies, 12 (15%) had hematological malignancies, and 6 (7%) had received transplantations. All patients received immunosuppressive agents or antitumor chemotherapeutic drugs. Plasma (1→3) β-D-glucan levels were elevated in 80% of patients, and were significantly reduced after treatment in both survivors and non-survivors. However, β-D-glucan increased in 18% of survivors and was normal in only 33% after treatment. Concomitant invasive pulmonary aspergillosis was detected in 5 patients. Fifty-six respiratory samples were stored for genotyping. A dihydropteroate synthase mutation associated with trimethoprim-sulfamethoxazole resistance was found in only 1 of the 53 patients. The most prevalent genotype of mitochondrial large-subunit rRNA was genotype 1, followed by genotype 4. The most prevalent genotype of internal transcribed spacers of the nuclear rRNA operon was Eb, followed by Eg and Bi. Thirty-day mortality was 24%, in which logistic regression analysis revealed association with serum albumin and mechanical ventilation, but no association with genotypes.. In non-HIV PCP, poorer general and respiratory conditions at diagnosis were independent predictors of mortality. β-D-glucan may not be useful for monitoring the response to treatment, and genotypes were not associated with mortality.

Topics: Adult; Aged; Aged, 80 and over; beta-Glucans; DNA, Bacterial; DNA, Mitochondrial; Female; Genotype; HIV Infections; Humans; Japan; Male; Middle Aged; Opportunistic Infections; Pneumocystis carinii; Pneumonia, Pneumocystis; Prognosis; Retrospective Studies; Young Adult

We have evaluated the contribution of the 1,3-beta-d-glucan (BG) assay for the screening of invasive fungal infections (IFIs) in patients with haematological malignancies. Serum samples from patients at risk of IFI were collected twice a week and retrospectively tested using the BG assay. BG screening was performed on 1143 samples from 91 patients during 104 anticancer treatment cycles. Proven and probable cases of IFI occurred in 9 (8.7 %) treatment cycles. Depending on the criterion of positivity used (1x >60 pg ml(-1), 1x >80 pg ml(-1), 2x >60 pg ml(-1) or 2x >80 pg ml(-1)) the sensitivity and specificity were 89, 89, 67 and 44 %, and 20, 48, 33 and 56 %, respectively. Although the test was marked as positive in 82, 68, 54 and 45 % of all the treatment cycles, in the majority of cases, these positivities were probably false. The major limit of the BG test was an extremely low positive predictive value (10 to 12 %). We have analysed mucositis, candida colonization, bacteraemia, use of antimicrobials, erythrocyte and thrombocyte filtered blood products, collecting tubes or sampling via venous catheters. Even though no factor is a major source of BG, it could at least partially influence BG assay performance. Thus, BG detection has a limited usefulness as a screening method for IFIs in patients with haematological malignancies.

Topics: Antineoplastic Agents; beta-Glucans; Female; Hematologic Neoplasms; Humans; Immunoassay; Immunocompromised Host; Male; Mycoses; Opportunistic Infections; Predictive Value of Tests; Sensitivity and Specificity

Topics: Antigens, Fungal; beta-Glucans; Biomarkers; Colorimetry; Humans; Immunity, Cellular; Immunocompromised Host; Mycoses; Nephelometry and Turbidimetry; Opportunistic Infections; Reference Values; Specimen Handling; Sugar Alcohols

1,3-beta-D glucan (BG) -- the antigen of fungal cell wall can be detected by a commercially available test for early detection of invasive fungal infections (IFI). The main advantage of this test is its broad coverage of fungal species. The aim of our study was to evaluate usefulness of BG detection for screening of IFI and for confirmation of galactomannan (GM) positive blood samples. Combination of the results of both tests could lead to correct and early diagnosis of invasive aspergillosis (IA).. Between January 2005 and July 2007 blood samples were collected in patients from intermediate to high risk of IFI. Moreover, between February and October 2007 all patients that had consecutive positive results of GM had their positive symplex tested also for BG.. In BG screening study, 1154 of blood samples from 104 treatment cycles were tested for BG. The incidence of IFI was 17.3 % (n = 18) and probable or proven IFI was detected in 9 cases (8.6%). The highest sensitivity, specificity, PPV and NPV (88.9 %, 40.7 %, 13.6 % and 97.2 %) were obtained when as criteria for positivity cut off 80 pg/ml and one positive result were used. When consecutive positivity of the test was applied as criterium, cut off 60 pg/ml was found more useful (sensitivity 66.7 %, specificity 47.7 %, PPV 11.8 % and NPV 93.2 %). Low PPV, caused by frequent false positive results, was identified as main limitation of this assay. 65 treatment cycles were positive if 1 sample above 80 pg/ml was used as a cut of for positivity. If consecutive positivity with cut off 60 pg/ml was used, 58 treatment cycles were positive. But in 51 (78.4 %) and 45 (77.5 %) cases, respectively, the positivity was not associated with IFI (false positivity). We did not find any correlation between positive BG assay result and frequency of empirical antifungal treatment, mucositis, yeast colonization, administration of selected antibiotics or infusion solutions or bacteriaemia. In our confirmation study, 40 GM positive episodes in 39 patients were identified. In 31 (78 %) GM positivity was false and was not associated with clinical signs and symptoms of IA. Sensitivity of GM detection in IA was 100 % but PPV only 18 %. Confirmation of consecutive GM positive samples (using cut off index positivity 0,5) by consecutive positivity of BG (with cut off 60 pg/ml) was found very useful for diagnosis of IA -- most of GM false positive results were eliminated and PPV increased to 88 %.. Our analysis focused on routine use of BG test for panfungal screening of IFI in patients with hematological malignancy and confirmed limited usefulness of this test in such setting. Low sensitivity together with low PPV are major limits of this test. On the other hand, BG testing seems to be a promising tool for confirmation of consecutive GM positive result in serum in patients with IA. Positivity of both tests could increase their PPV of tests and eliminate false positive results.

Topics: Antigens, Fungal; beta-Glucans; Female; Galactose; Hematologic Neoplasms; Humans; Male; Mannans; Mycoses; Opportunistic Infections; Predictive Value of Tests; Proteoglycans; Sensitivity and Specificity

A 78-year-old man administered prednisolone and cyclosporin A for bullous pemphigoid and found in computed tomography (CT) to have a left-lung nodule was suspected of having a fungal infection due to elevated blood (1-->3)-beta-D-glucan. Despite empirical antifungal therapy, however, the nodule grew, followed by new nodules in both lungs. Disseminated nocardiosis was eventually diagnosed based on sputum, blood, and skin cultures growing Nocardia sp. Antinocardial treatment with imipenem/cilastatin and amikacin was started. The patient then developed pneumocystis pneumonia for which pentamidine was added. He had recovered completely when antimicrobial therapy was completed. A wide variety of microorganisms may infect patients with impaired cellular immunity, simultaneously involving multiple organisms in some cases. Definitive microbiological diagnosis with culture or biopsy specimens is therefore crucial for appropriate management.

Topics: Aged; beta-Glucans; Cyclosporine; Humans; Male; Nocardia Infections; Opportunistic Infections; Pemphigoid, Bullous; Pneumonia, Pneumocystis; Prednisolone

Topics: Antifungal Agents; Antigens, Fungal; Aspergillosis; beta-Glucans; Biomarkers; Candidiasis; Humans; Neutropenia; Opportunistic Infections; Proteoglycans; Sensitivity and Specificity