laminaran and Aspergillosis

Invasive mould infections (IMIs), such as invasive aspergillosis or mucormycosis, are a major cause of death in patients with haematological cancer and in patients receiving long-term immunosuppressive therapy. Early diagnosis and prompt initiation of antifungal therapy are crucial steps in the management of patients with IMI. The diagnosis of IMI remains a major challenge, with an increased spectrum of fungal pathogens and a diversity of clinical and radiological presentations within the expanding spectrum of immunocompromised hosts. Diagnosis is difficult to establish and is expressed on a scale of probability (proven, probable and possible). Imaging (CT scan), microbiological tools (direct examination, culture, PCR, fungal biomarkers) and histopathology are the pillars of the diagnostic work-up of IMI. None of the currently available diagnostic tests provides sufficient sensitivity and specificity alone, so the optimal approach relies on a combination of multiple diagnostic strategies, including imaging, fungal biomarkers (galactomannan and 1,3-β-d-glucan) and molecular tools. In recent years, the development of PCR for filamentous fungi (primarily Aspergillus or Mucorales) and the progress made in the standardization of fungal PCR technology, may lead to future advances in the field. The appropriate diagnostic approach for IMI should be individualized to each centre, taking into account the local epidemiology of IMI and the availability of diagnostic tests.

Topics: Aspergillosis; Aspergillus fumigatus; beta-Glucans; Early Diagnosis; Galactose; Hematologic Neoplasms; Humans; Immunocompromised Host; Immunosuppression Therapy; Invasive Fungal Infections; Magnetic Resonance Imaging; Mannans; Mucor; Mucormycosis; Organ Transplantation; Polymerase Chain Reaction; Positron Emission Tomography Computed Tomography; Tomography, X-Ray Computed

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

The biomarkers galactomannan and 1,3-β-d-glucan have been well studied over the past years and are gaining a role in the diagnosis of invasive fungal infections. Although not as well studied until recently, molecular methods for the diagnosis of invasive fungal infection are also being evaluated. Outcomes data for molecular testing are expanding, but have not yet provided enough evidence for inclusion of molecular diagnostics in formal clinical guidelines. Lack of standardization and validation of the various molecular assays and platforms has hindered their widespread acceptance in the evaluation of invasive fungal infections, although the future is promising.

Topics: Aspergillosis; beta-Glucans; Biomarkers; Bronchoalveolar Lavage Fluid; Candidiasis; False Positive Reactions; Galactose; Humans; Mannans; Pathology, Molecular; Polymerase Chain Reaction; Predictive Value of Tests; Sugar Alcohols

Topics: Antigens, Fungal; Aspergillosis; Aspergillus; beta-Glucans; Breath Tests; DNA, Fungal; Early Diagnosis; Galactose; Hematopoietic Stem Cell Transplantation; Humans; Immunocompromised Host; Leukemia; Lung; Mannans; Neutropenia; Organ Transplantation; Transplantation Immunology

Although invasive fungal infections (IFIs) are relatively rare, they are important causes of morbidity and mortality in immunocompromised pediatric patients. Early and precise diagnosis of IFI is important to allow antifungal treatment to be started in time and to reduce the unnecessary use of toxic antifungal agents. Although traditional approaches such as direct microscopic examination, histopathological evaluation and cultivation are still gold standard, the diagnosis of IFI is generally difficult because of inadequate sensitivity and specificity with these tests. Commercial systems detecting the Aspergillus cell wall antigen galactomannan and 1,3-β-D-glucan are seen as the most convenient nonculture methods for the diagnosis of the IFI and monitoring of antifungal treatment. Several molecular methods have been described for the diagnosis of opportunistic mycoses. However, they have not been standardized and have only been used in experimental studies.

Topics: Aspergillosis; Aspergillus; beta-Glucans; Candida; Candidiasis, Invasive; Child; Culture Techniques; Diagnostic Techniques and Procedures; Early Diagnosis; Galactose; Humans; Mannans; Sensitivity and Specificity

The pulmonary innate immune system clears inhaled Aspergillus fumigatus conidia (spores) from terminal airways. Failure to control conidial germination in immune compromised hosts can result in hyphal tissue invasion and fatal disease. Insight into the molecular recognition of A. fumigatus by host leukocytes indicates that the innate immune system exploits obligate changes in fungal cell wall composition that occur at the first stage of germination, conidial swelling. Germinating spores activate at least two host signal transduction pathways. Surface exposure of fungal beta-(1,3) glucan, a polysaccharide constituent of the fungal cell wall, triggers dectin-1 signaling by host phagocytes. Spore germination leads to the induction of Toll-like receptor (TLR) signaling as well. This stage-specific recognition mechanism focuses host antifungal responses on cells with the potential for tissue invasion and may serve to limit potentially deleterious effects of inflammation in space and time. Fungal beta-(1,3) glucan not only activates host innate immune responses but also represents the target of echinocandin drugs. The activity of echinocandin drugs has largely been understood on the basis of pharmacologic growth inhibition of yeast and moulds, resulting in lysis of yeast cells and stunting of dysmorphic hyphae. The recognition that fungal beta-1,3 glucan activates dectin-1 signaling suggests that echinocandin drugs may exert immune modulatory effects by altering innate immune responses to drug-treated fungal cells, a view supported by recent data from studies on C. albicans, A. fumigatus, and non-Aspergillus moulds.

Topics: Aspergillosis; Aspergillus fumigatus; beta-Glucans; Echinocandins; Humans; Immunity, Innate; Immunologic Factors; Lectins, C-Type

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

Micafungin is a relatively broad-spectrum antifungal agent available for clinical use in the US and Japan. By inhibiting the production of beta-1,3-glucan, an essential fungal cell wall component, micafungin has reduced toxicity to mammalian cells while maintaining potent antifungal activity against many pathogenic fungi including polyene- and azole-resistant isolates. Indeed, micafungin has been shown to be efficacious in the treatment of infections caused by Candida and Aspergillus species in clinical trials without the associated toxicities of amphotericin B formulations and drug interactions that occur with the azoles. In this review, the pharmacology, spectrum of activity, clinical efficacy and safety profile of micafungin are discussed.

Topics: Antifungal Agents; Aspergillosis; Aspergillus; beta-Glucans; Candida; Candidiasis; Drug Interactions; Drug Resistance, Fungal; Echinocandins; Fungi; Humans; Lipopeptides; Lipoproteins; Micafungin; Microbial Sensitivity Tests; Peptides, Cyclic

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

Topics: Amphotericin B; Antifungal Agents; Aspergillosis; Aspergillus; beta-Glucans; Biomarkers; Diagnosis, Differential; Echinocandins; Glucans; Humans; Lipopeptides; Lipoproteins; Micafungin; Peptides, Cyclic; Pyrimidines; Serologic Tests; Triazoles; Voriconazole

Invasive fungal infections have emerged as important causes of morbidity and mortality in neutropenicand some other immunocompromised hosts; Candida and Aspergillus are among the major pathogens in this patient population. The clinical diagnosis of these infections is not specific and the traditional mycological methods for them not sensitive, with limits in the early detection of the pathogen. The potential additives or complements to the laboratory diagnosis of invasive candidiasis and aspergillosis are two non-culture-based methods, serodiagnostic methods and molecular ones. The former methods include the detection of pathogen-specific antigens, antibodies, metabolites and cell wall components. Several have already become standard laboratory tools and some others are under active investigation for developing new, more accurate detection systems. In this review, I will discuss the current status and future potential of serodiagnostic methods, highlighting both their technical and clinical implications.

Topics: Animals; Antibodies, Fungal; Antibody Specificity; Antigens, Fungal; Aspergillosis; Aspergillus; beta-Glucans; Biomarkers; Candida; Candidiasis; Cell Wall; Glucans; Humans; Mannans; Mannitol; Serologic Tests; Sugar Alcohols

The dramatic increase in nosocomial invasive mycoses over the past two decades has led to increased interest in the area of antifungal development. Unfortunately, the infusion of new diagnostic technology into the clinical mycology laboratory has lagged behind. Although newer, automated, continuous-monitoring blood culture systems are as sensitive as the older, manual "gold standard" system, the recovery of fungi from blood, as well as other clinical specimens, remains an insensitive marker for invasive fungal infection. Antigen assays for the rapid diagnosis of invasive fungal infections are in development, and galactomannan and glucan are two such promising antigens. Glucan may be present in the blood of patients with infection secondary to a wide variety of fungal pathogens, including Candida, Aspergillus, Fusarium, Saccharomyces, Trichosporon and Acremonium species. Early data suggest galactomannan may be present in the blood in detectable levels very early in the course of invasive aspergillosis. The galactomannan assay currently undergoing evaluations may actually be positive prior to the clinical suspicion for infection and may be useful in monitoring therapeutic response as well; however, the etiology of false-positive results following cytotoxic chemotherapy still has to be elucidated. PCR assays are also being developed in the research laboratory, however, the PCR assays will require a significant amount of adaptation and validation before they are ready for clinical care. Well-planned studies to evaluate the performance characteristics as well as appropriate clinical and cost-effective application of these new tests are needed.

Topics: Antigens, Fungal; Aspergillosis; beta-Glucans; Biotechnology; Candidiasis; Centrifugation; Culture Media; Enzyme-Linked Immunosorbent Assay; Fungemia; Glucans; Humans; Immunocompromised Host; Mannans; Medical Laboratory Science; Membrane Glycoproteins; Mycoses; Polymerase Chain Reaction

The therapeutic landscape for mycotic infections is shifting. New generation azoles that are active against clinically relevant, drug-resistant fungal pathogens have improved bioavailability, half-lives and safety profiles. Acylated cyclic peptide inhibitors of beta(1,3)glucan synthesis with origins as fungal metabolites provide an alternative and highly-selective mode of action, targeting cell-wall biogenesis in important pathogens such as Candida and Aspergillus species. The development, in each structural class, of compounds that have advanced to late-stage clinical trials is summarized in this review.

Topics: Antifungal Agents; Aspergillosis; Aspergillus; beta-Glucans; Candida; Candidiasis; Cell Wall; Clinical Trials as Topic; Glucans; Humans; Research

The clinical utility of Pastorex Aspergillus, a commercially available circulating aspergillus galactomannan antigen detection kit was evaluated. In animal models of pulmonary aspergillosis, it was extremely sensitive for detection of not only A. fumigatus antigen but also antigens of A. flavus and A. niger both in serum and urine. In a preliminary study in autopsied or clinically proven cases with aspergillus infections a high positive rate of antigen detection was obtained when it was applied prospectively. A total of 1,373 clinical samples obtained from patients with suspected aspergillus infection were examined. Among 67 patients giving antigen-positive results in their clinical samples including serum, urine, sputum and others, 17 patients proved to have aspergillus infection by histological or cultural studies. Sixteen patients were judged to be suspicious of aspergillus infection. Measurement of serum (1 --> 3) beta-D glucan by G-test in these cases was well correlated to the results of the antigen detection test. However, the serum showed often antigen-negative even when it was examined at the peak of illness. The rapid clearance of the antigen from circulation was considered to be one of the reasons for this phenomenon. In these cases, antigen detection in samples other than serum, such as urine, sputum, and pleural fluid was also useful. In conclusion, when using Pastorex Aspergillus to obtain the early diagnosis of aspergillus infection frequent examination in different types of samples is recommended.

Topics: Animals; Antigens, Fungal; Aspergillosis; Aspergillus; beta-Glucans; Galactose; Glucans; Humans; Lung Diseases, Fungal; Mannans; Rats; Reagent Kits, Diagnostic; Serologic Tests

(1-->3)-beta-D-Glucan is one of the major structural components of fungi, and it seems that it can be detected by the fractionated (1-->3)-beta-D-glucan-sensitive component from a Limulus lysate, factor G. We evaluated the concentration of (1-->3)-beta-D-glucan by using factor G and other fungal antigens in 24 patients with clinical evidence of mycosis and 36 healthy subjects. The mean concentration of (1-->3)-beta-D-glucan in the plasma of the healthy subjects was found to be 2.7 +/- 1.9 pg/ml (range, < 6.9 pg/ml), and it was found to be substantially higher in all 11 patients with candidemia (mean, 2,207.4 pg/ml; range, 325.4 to 8,449.0 pg/ml). Eight of those 11 patients with candidemia (73%) were positive for the Cand-Tec heat-labile candida antigen and only 3 patients (27%) were positive for mannan antigen. Three patients with invasive pulmonary aspergillosis were positive for galactomannan and had, in addition, high concentrations of (1-->3)-beta-D-glucan (mean, 323.3 pg/ml; range, 27.0 to 894.0 pg/ml). All 10 patients with cryptococcosis (including 2 patients with probable cryptococcosis) were positive for cryptococcal antigen by the Eiken latex test; however, (1-->3)-beta-D-glucan levels were not elevated in these patients (mean, 7.0 pg/ml; range, < 16.5 pg/ml). Our results indicated that (1-->3)-beta-D-glucan levels are elevated in patients with candidiasis and aspergillosis but not in those with cryptococcosis.

Topics: Adult; Antigens, Fungal; Aspergillosis; beta-Glucans; Candidiasis; Cryptococcosis; Female; Fungemia; Galactose; Glucans; Humans; Limulus Test; Male; Mannans; Middle Aged; Serologic Tests

We previously reported medicinal chemistry efforts that identified MK-5204, an orally efficacious β-1,3-glucan synthesis inhibitor derived from the natural product enfumafungin. Further extensive optimization of the C2 triazole substituent identified 4-pyridyl as the preferred replacement for the carboxamide of MK-5204, leading to improvements in antifungal activity in the presence of serum, and increased oral exposure. Reoptimizing the aminoether at C3 in the presence of this newly discovered C2 substituent, confirmed that the (R) t-butyl, methyl aminoether of MK-5204 provided the best balance of these two key parameters, culminating in the discovery of ibrexafungerp, which is currently in phase III clinical trials. Ibrexafungerp displayed significantly improved oral efficacy in murine infection models, making it a superior candidate for clinical development as an oral treatment for Candida and Aspergillus infections.

Topics: Administration, Oral; Animals; Antifungal Agents; Aspergillosis; Aspergillus; beta-Glucans; Candida albicans; Candidiasis; Disease Models, Animal; Glycosides; Half-Life; Mice; Structure-Activity Relationship; Triterpenes

Topics: Aspergillosis; beta-Glucans; Candidiasis; Humans; Mycoses; Plasma; Pneumonia, Pneumocystis; Reagent Kits, Diagnostic; Sensitivity and Specificity; Serologic Tests; Serum

Echinocandins are antifungal agents that specifically inhibit the biosynthesis of 1,3-β-D-glucan, a major structural component of fungal cell walls. Echinocandins are recommended as first-line or alternative/salvage therapy for candidiasis and aspergillosis in antifungal guidelines of various countries. Resistance to echinocandins has been reported in recent years. The mechanism of echinocandin resistance involves amino acid substitutions in hot spot regions of the FKS gene product, the catalytic subunit of 1,3-β-D-glucan synthase. This resistance mechanism contributes to not only acquired resistance in Candida spp., but also inherent resistance in some pathogenic fungi. An understanding of the echinocandin resistance mechanism is important to develop both effective diagnosis and treatment options for echinocandin-resistant fungal diseases.

Topics: Amino Acid Substitution; Antifungal Agents; Aspergillosis; Aspergillus; beta-Glucans; Candida; Candidiasis; Catalytic Domain; Drug Resistance, Fungal; Echinocandins; Glucosyltransferases

Aspergillus is a medically important fungal genus that causes a life-threatening infection known as aspergillosis in immunocompromised patients. β-1,3-Glucan is detected in the plasma of patients with aspergillosis and appears to be useful for the diagnosis of aspergillosis. In this study, we cultured Aspergillus spp. in a chemically defined liquid medium and prepared an Aspergillus water-soluble fraction (ASWS) from the culture supernatants. ASWS was found to be primarily composed of polysaccharides and proteins. Nuclear magnetic resonance analysis suggested that ASWS is a complex carbohydrate, consisting of α-1,3-glucan, β-1,3-glucan, galactomannan, and protein. The ASWS from Aspergillus fumigatus showed limulus factor G activity, whereas zymolyase-treated ASWS did not. ASWS was eliminated from the blood more rapidly than Aspergillus solubilized cell wall β-glucan. We analyzed the reactivity of human immunoglobulin towards ASWS by an enzyme-linked immunosorbent assay. Anti-ASWS antibodies were detected in human sera, with titers differing among individuals. This study demonstrated that the ASWS corresponds to the limulus factor G-activating substance found in the blood of patients with aspergillosis.

Topics: Animals; Antibodies, Fungal; Aspergillosis; Aspergillus fumigatus; beta-Glucans; Biomarkers; Fungal Proteins; Galactose; Glucans; Humans; Immunoglobulins; Male; Mannans; Mice, Inbred DBA; Solubility; Water

Diagnosis of pneumocystis pneumonia (PCP) relies on microscopic visualization of P. jirovecii, or detection of Pneumocystis DNA in respiratory specimens, which involves invasive procedures such as bronchoalveolar lavage. The (1-3)-β-D-glucan (BG) assay has been proposed as a less invasive and less expensive diagnostic test to rule out PCP. We therefore compared blood levels of BG in patients with PCP with those of patients with candidemia, chronic disseminated candidiasis (CDC), invasive aspergillosis, mucormycosis, and tuberculosis and those of healthy volunteers.. Adult patients who were diagnosed with PCP, candidemia, CDC, invasive aspergillosis, mucormycosis, and tuberculosis whose blood samples were available, and healthy volunteers were enrolled in a tertiary hospital in Seoul, South Korea, during a 21-month period. The blood samples were assayed with the Goldstream Fungus (1-3)-β-D-glucan test (Gold Mountain River Tech Development, Beijing, China).. A total of 136 individuals including 50 patients P. jirovecii,15 candidemia, 6 CDC, 15 invasive aspergillosis, 10 mucormycosis, and 40 controls (20 TB and 20 healthy volunteers) were included. The mean±SD of the concentration of 1-3-β-D-glucan in the patients with PCP (290.08 pg/mL±199.98) were similar to those of patients with candidemia (314.14 pg/mL±205.60, p = 0.90 at an α = 0.005) and CDC (129.74 pg/mL±182.79, p = 0.03 at an α = 0.005), but higher than those of patients with invasive aspergillosis (131.62 pg/mL±161.67, p = 0.002 at an α = 0.005), mucormycosis (95.08 pg/mL±146.80, p<0.001 at an α = 0.005), and tuberculosis (103.31 pg/mL±140.81, p<0.001 at an α = 0.005) as well as healthy volunteers (101.18 pg/mL±197.52, p<0.001 at an α = 0.005). At a cut-off value > 31.25 pg/mL, which is highly sensitive for PCP versus tuberculosis plus healthy volunteers at the expense of specificity, the BG assay had a sensitivity of 92% (95% CI 81%-98%) and a specificity of 55% (95% CI 39%-71%).. The BG assay appears to be a useful adjunct test for PCP.

Topics: Adult; Aged; Aspergillosis; beta-Glucans; Candidiasis; Case-Control Studies; Diagnosis, Differential; Female; Healthy Volunteers; Humans; Male; Middle Aged; Mucormycosis; Pneumocystis carinii; Pneumonia, Pneumocystis; Republic of Korea; Tuberculosis, Pulmonary

Pseudallescheria boydii is a fungal organism known to affect immunocompromised patients. This organism is known to cause, in severe cases, invasive infection of various organs such as the central nervous, cardiovascular, and respiratory systems. We report an unusual case of pulmonary P. boydii pneumonia in an immunocompromised critically ill patient with a co-infection of Aspergillus fumigatus and Aspergillus terreus with ARDS. This case highlights the importance of a high index of suspicion for superimposed fungal infections in patients who are critically ill and immunocompromised. Uncommon fungal pathogens should be considered in the differential diagnosis of respiratory failure, especially if diagnostic markers such as galactomannan (from BAL and serum) or 1,3-beta-D-glucan are elevated. Further diagnostic interventions are warranted when insufficient clinical improvement is observed to prevent treatment failure and adverse outcomes.

Topics: Aged; Amphotericin B; Antifungal Agents; Aspergillosis; Aspergillus fumigatus; beta-Glucans; Clarithromycin; Coinfection; Critical Illness; Extracorporeal Membrane Oxygenation; Galactose; Hematopoietic Stem Cell Transplantation; Humans; Immunocompromised Host; Linezolid; Male; Mannans; Meropenem; Pneumonia; Pseudallescheria; Severe Acute Respiratory Syndrome; Thienamycins; Transplant Recipients; Voriconazole

High mortality rates of invasive fungal disease (IFD), especially invasive aspergillosis (IA), in immunocompromised haematological patients and current diagnostic limitations require improvement of detection of fungal pathogens by defining the optimal use of biomarkers and clinical samples. Concurrent bronchoalveolar lavage (BAL) and peripheral blood samples of 99 haematological patients with suspected IFD were investigated within a multicentre prospective study. Diagnostic performance of a galactomannan (GM) enzyme immune assay (EIA), a 1,3-β-D-glucan assay (BDG), an Aspergillus PCR, and a multifungal DNA-microarray (Chip) alone or in combination were calculated. IFD were classified as proven (n=3), probable (n=34), possible (n=33), and no IFD (n=29) according to EORTC/MSG criteria. GM, PCR, and Chip showed superior diagnostic performance in BAL than in blood, whereas specificity of BDG in BAL was poor (48% (14/29)). The combination of GM (BAL) with BDG (blood) showed sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and DOR (diagnostic odds ratio) of 92% (34/37), 93% (27/29), 94%, 90%, and 153.0, respectively. Combining GM (BAL) with PCR (BAL) showed convincing diagnostic potential for diagnosing IA with sensitivity, specificity, PPV, NPV, and DOR of 85% (17/20), 97% (28/29), 94%, 90%, and 158.7. Addition of the DNA-microarray resulted in further detection of two mucormycetes infections. In 1 out of 15 Aspergillus DNA-positive samples a triazole resistance-mediating Cyp51A mutation was found. Combination of biomarkers is superior to their sole use in diagnosing IFD, particularly IA. Integrating blood and BAL samples into a diagnostic algorithm is an advantageous approach.

Topics: Aspergillosis; Aspergillus; Azoles; beta-Glucans; Bronchoalveolar Lavage Fluid; Galactose; Humans; Invasive Fungal Infections; Mannans; Microbiological Techniques; Molecular Diagnostic Techniques; Multiplex Polymerase Chain Reaction; Oligonucleotide Array Sequence Analysis; Prospective Studies; Sensitivity and Specificity

Echinocandins inhibit β-1,3-glucan synthesis and are one of the few antimycotic drug classes effective against Aspergillus spp. In this study, we characterized the β-1,3-glucan synthase Fks1 of Aspergillus fumigatus, the putative target of echinocandins. Data obtained with a conditional mutant suggest that fks1 is not essential. In agreement, we successfully constructed a viable Δfks1 deletion mutant. Lack of Fks1 results in characteristic growth phenotypes similar to wild type treated with echinocandins and an increased susceptibility to calcofluor white and sodium dodecyl sulfate. In agreement with Fks1 being the only β-1,3-glucan synthase in A. fumigatus, the cell wall is devoid of β-1,3-glucan. This is accompanied by a compensatory increase of chitin and galactosaminogalactan and a significant decrease in cell wall galactomannan due to a massively enhanced galactomannan shedding. Our data furthermore suggest that inhibition of hyphal septation can overcome the limitations of echinocandin therapy. Compounds inhibiting septum formation boosted the antifungal activity of caspofungin. Thus, development of clinically applicable inhibitors of septum formation is a promising strategy to improve existing antifungal therapy.

Topics: Antifungal Agents; Aspergillosis; Aspergillus fumigatus; Benzenesulfonates; beta-Glucans; Caspofungin; Cell Wall; Chitin; Echinocandins; Galactose; Glucosyltransferases; Hyphae; Lipopeptides; Mannans; Mutation; Phenotype; Polysaccharides

To observe Dectin-1 expression in fungal keratitis on rat models and to determine the role of Dectin-1 in innate immune response to Aspergillus fumigatus.. Wistar rats were randomly divided into control, fungal keratitis and pretreatment (pretreated with Laminarin) groups. Samples were used for conducting immunohistochemical staining and real-time PCR to observe expression of cytokines like CCL2, CCL3, CXCL1, CXCL2, IL-1β, TNF-α, IL-6, IL-10.. After fungal stimulations, all 7 inflammatory factors, except IL-10, increased with different levels. After 4 h of fungal stimulations, IL-1β, IL-6, CCL2, CXCL1 and CXCL2 of pretreatment groups were significantly (p < 0.05) lower than fungal groups, while the other 3 cytokines had no significant changes. After 8 h of fungal stimulations, IL-6 and CXCL1 of pretreatment groups were still significantly (p < 0.05) lower than fungal groups.. With progress of fungus stimulation, expression of IL-1β,CXCL1 ,CXCL2,MCP-1 gradually increased, whilepretreated with Laminarin to block Dectin-1, these expression decreased, indicating that Dectin-1 maypromote immune reaction through them. IL-10 decreased in fungal group because of itsimmunosuppressive effect at 4h, and it began to increase at 8h to suppress Th1 inflammation response inorder to avoid excessive tissue damage.. Dectin-1 in early period of innate immune responses in rat fungal keratitis might work through IL-1β, IL-6, CCL2, CXCL1, CXCL2 to recruit neutrophils and macrophages to participate anti-fungal immunity.

Topics: Animals; Aspergillosis; Aspergillus fumigatus; Corneal Ulcer; Cytokines; Epithelium, Corneal; Eye Infections, Fungal; Glucans; Hypolipidemic Agents; Immunity, Innate; Immunohistochemistry; Lectins, C-Type; Macrophages; Neutrophils; Rats; Rats, Wistar; Real-Time Polymerase Chain Reaction

Avian aspergillosis, most often caused by Aspergillus fumigatus, is a common and devastating disease affecting a range of bird species. Early diagnosis is difficult and often unreliable. The current study evaluated the utility of measuring (1-->3)-beta-D-glucan (BG) concentrations in avian plasma samples to aid in the diagnosis of aspergillosis. We evaluated a commercially available BG assay (Fungitell, Beacon Diagnostics) using 178 plasma samples from naturally infected, experimentally infected, and aspergillosis-free birds. Although there was variation in BG concentration, as reflected by high standard deviations, seabirds with confirmed aspergillosis had the highest mean BG concentrations (M = 3098.7 pg/dl, SD = 5022.6, n = 22) followed by companion avian species and raptors with confirmed aspergillosis (M = 1033.8 pg/dl, SD = 1531.6, n = 19) and experimentally infected Japanese quail (Coturnix japonica; M = 1066.5 pg/dl, SD = 1348.2, n = 17). Variation in severity of disease, differences among species of birds with and without disease, and also different levels in environmental exposure likely contribute to the differences among avian groups. The overall sensitivity and specificity of the BG test for diagnosis of aspergillosis in birds was 60.0 and 92.7%, respectively, with an overall optimized avian cut-offvalue of > or = 461 pg/dl for positive disease. Our findings suggest that, although BG concentrations are highly variable between and within different avian groups, it could serve as a useful adjunctive diagnostic test for aspergillosis that is applicable to multiple avian species in some settings, particularly as a negative predictor of infection.

Topics: Animals; Aspergillosis; Aspergillus fumigatus; beta-Glucans; Bird Diseases; Birds; California; Lung Diseases, Fungal; Sensitivity and Specificity; Serologic Tests; Species Specificity

Airway epithelial cells are the first cells to be challenged upon contact with the conidia of Aspergillus. In response, they express pattern-recognition receptors that play fundamental roles as sentinels and mediators of pulmonary innate immunity. The C-type lectin Dectin-1 is expressed predominantly on the surface of myeloid lineage cells. We examined the induction, regulation, and functions of Dectin-1 in pulmonary epithelial cells by challenging human bronchial epithelial (HBE) cells with A. fumigatus. Inflammatory, antimicrobial peptide genes and reactive oxygen species (ROS) were quantified, with and without knockdown of Dectin-1. We found that A. fumigatus induced the expression of Dectin-1 mRNA and protein in HBE cells in a toll-like receptor (TLR) 2-dependent manner. In addition, A. fumigatus-mediated generation of ROS was dependent on the upregulation of Dectin-1. Moreover, A. fumigatus actively induced the expression of TNFα, GM-CSF, IL8, HBD2, and HBD9. Knockdown of Dectin-1 inhibited TNFα, IL8, HBD2, and HBD9 expression. Hence, Dectin-1 was required for the upregulation of pro-inflammatory cytokines and antimicrobial peptides. Finally, knockdown of TLR2 significantly inhibited Dectin-1 upregulation. Our results demonstrate the novel induction of Dectin-1 in human bronchial epithelial cells and its critical role in the innate immune response against A. fumigatus in non-phagocytic cells.

Topics: Aspergillosis; Aspergillus fumigatus; beta-Defensins; Bronchi; Bronchial Provocation Tests; Cell Line, Tumor; Epithelial Cells; Flow Cytometry; Gene Expression Regulation; Gene Knockdown Techniques; Glucans; Humans; Immunity, Innate; Interleukin-8; Lectins, C-Type; Microscopy, Fluorescence; Polysaccharides; Reactive Oxygen Species; RNA, Messenger; Spores, Fungal; Time Factors; Toll-Like Receptor 2; Tumor Necrosis Factor-alpha

The aim of this study was to investigate the interaction between intravenous piperacillin/tazobactam treatment and Aspergillus galactomannan antigen (GM) and 1,3-beta-D: -glucan (BDG) test results in patients without known risk factors for invasive fungal infections (IFI).. Patients without known risk factors for IFI and who were to receive piperacillin/tazobactam monotherapy were considered eligible for the study. Serum samples were obtained both before and after antibiotic infusion on the first, third, seventh and tenth days of a piperacillin/tazobactam treatment course and 4 days after the last dose. GM was determined by Platelia Aspergillus ELISA (Bio-Rad Laboratories) and BDG was assayed using the Fungitell kit (Associates of Cape Cod, East Falmouth, MA) according to manufacturers' specifications.. A total of 135 serum samples were collected from 15 patients. When a cut-off level of >or=0.7 was used for GM positivity, there were no false positive results. When a cut-off level of >or=0.5 was used, six serum samples were positive. There were no statistically significant differences between the median GM indices or median BDG levels of the various sampling times. However, 24 of 135 serum samples were positive for BDG for a threshold of 80 pg/mL. After ruling out fungal infections and all known potential causes of false BDG positivity, environmental contamination remained a possible cause of BDG reactivity.. No significant interaction was observed between piperacillin/tazobactam administration and Aspergillus GM and BDG assays. Positive results for these tests should be evaluated cautiously in patients at high risk for IFI receiving piperacillin/tazobactam.

Topics: Adult; Aged; Anti-Bacterial Agents; Antigens, Fungal; Aspergillosis; Aspergillus; beta-Glucans; False Positive Reactions; Female; Galactose; Humans; Infusions, Intravenous; Male; Mannans; Microbiological Techniques; Middle Aged; Mycology; Penicillanic Acid; Piperacillin; Piperacillin, Tazobactam Drug Combination; Risk Factors

The usefulness of BG as a marker has been reported in patients with pulmonary aspergillosis. However, no data have demonstrated the behavior of BG in sino-orbital IA. We encountered a case of sino-orbital IA and demonstrated changes in the BG level, radiological images, and pathological features.. A 63-year-old Japanese woman suffered from invasive sino-orbital aspergillosis. The serum BG level measured immediately before surgery was 37.2pg/mL (normal value <3.4pg/mL). Endoscopic sinus surgery revealed some necrotic tissue extending from the ethmoid sinus to the orbit. The infiltrating Aspergillus was revealed in the pathological examination. The BG level decreased to the normal value. However, CT revealed a high-density area; this may indicate that an aspergillosis lesion remained slightly in the orbit.. (1-->3)-beta-d-Glucan (BG) is a useful marker for diagnosing Aspergillus and evaluating the therapeutic effect of the treatment administered.

Topics: Antifungal Agents; Aspergillosis; beta-Glucans; Biomarkers; Drug Therapy, Combination; Ethmoid Sinusitis; Female; Follow-Up Studies; Humans; Middle Aged; Orbital Diseases; Predictive Value of Tests; Reoperation; Tomography, X-Ray Computed

The aim of this study was to detect Aspergillus fumigatus-specific DNA by nested PCR (nPCR) in serum and bronchoalveolar lavage (BAL) specimens of experimentally infected rats and compare the results with (1-3)-beta-D-glucan (BDG) and galactomannan (GM) detection. Sixty Wistar rats, immunosuppressed with an intraperitoneal injection of cyclophosphamide (70 mg kg(-1)) were infected with 1 x 10(6)A. fumigatus conidia. The rats were killed on days 1, 3, 5, 7 and 9 postinfection in groups of six each and their BAL, blood and lungs were cultured. The A. fumigatus-specific DNA, BDG and GM in serum and BAL were detected by nPCR, Fungitell kit and Aspergillus Platelia kit respectively. Base line values were obtained by using sera from six healthy rats. Except the lungs, blood and BAL specimens of all the infected rats were negative for A. fumigatus culture. The BDG, GM and nPCR positivity in serum specimens was 80%, 77% and 63% respectively. The sensitivity of GM and nPCR tests in BAL specimens was 77% and 70% respectively. The data suggest that BDG and GM appear early in the course of infection, and have similar kinetics (r = 0.483, P = 0.007). Hence, their combined detection could be useful in the early diagnosis of invasive aspergillosis.

Topics: Animals; Aspergillosis; Aspergillus fumigatus; beta-Glucans; Bronchoalveolar Lavage Fluid; DNA, Fungal; Female; Galactose; Humans; Lung; Lung Diseases, Fungal; Mannans; Polymerase Chain Reaction; Rats; Rats, Wistar; Sensitivity and Specificity; Specific Pathogen-Free Organisms

A case of cerebral aspergillosis was diagnosed by the detection of Aspergillus flavus-specific DNA in brain biopsy and serum specimens. The diagnosis was also supported by detection of elevated levels of galactomannan and (1-->3)-beta-d-glucan in serum specimens. Despite the presence of dichotomously branched septate hyphae in brain biopsy, the culture remained negative. The inability to isolate the organism in culture suggested that combined therapy of AmBisome and caspofungin was fungicidal for the fungus in the brain abscess.

Topics: Amphotericin B; Antifungal Agents; Aspergillosis; Aspergillus flavus; beta-Glucans; Brain; Brain Diseases; Caspofungin; Diagnosis, Differential; DNA, Fungal; Echinocandins; Electrophoresis, Agar Gel; Galactose; Humans; Lipopeptides; Male; Mannans; Middle Aged; Peptides, Cyclic; Polymerase Chain Reaction

The aim of this study was to evaluate the diagnostic value of Aspergillus terreus-specific DNA, (1-3)-beta-d-glucan (BDG), and galactomannan (GM) in immunosuppressed mice infected intravenously with A. terreus conidia and sacrificed in groups of 12 each on days 1, 3, 5, 7, and 9. A. terreus-specific DNA, BDG, and GM in serum and bronchoalveolar lavage (BAL) were detected by nested polymerase chain reaction (nPCR), Fungitell kit (Associates of Cape Cod, E. Falmouth, MA), and Aspergillus Platelia kit (Bio-Rad, Marnes-laCoquette, France), respectively. Cultures of lung homogenate of all the animals yielded A. terreus. The BDG positivity, GM positivity, and nPCR positivity in serum specimens were 43%, 78%, and 73%, respectively. Combined detection enhanced the positivity to 95% for A. terreus DNA and GM, 83% for GM and BDG, and 95% for DNA, GM, and BDG. In BAL, the GM positivity and nPCR positivity were 80% and 81%, respectively, whereas combined detection increased the positivity to 98%. Detection of GM and DNA offers a sensitive and specific diagnostic option for invasive aspergillosis.

Topics: Animals; Aspergillosis; Aspergillus; beta-Glucans; Bronchoalveolar Lavage Fluid; DNA, Fungal; Female; Galactose; Humans; Mannans; Mice; Mice, Inbred BALB C; Polymerase Chain Reaction; Reagent Kits, Diagnostic; Sensitivity and Specificity; Specific Pathogen-Free Organisms

Aspergillus markers are becoming increasingly important for the early diagnosis of invasive aspergillosis. The kinetics of release of these surrogate markers, however, is largely unknown. We investigated the release of beta-(1-5)-galactofuranosyl (galf) antigens (Platelia Aspergillus), 1,3-beta-D-glucan (BG) (Fungitell), and DNA (PCR) in an in vitro model of Aspergillus fumigatus. The results showed that release is correlated to the growth phase of the fungus, which depends on available nutrients. Whereas galf antigens and BG are released during logarithmic growth, DNA is released only after mycelium breakdown. During early logarithmic growth, galf antigens seem to be released somewhat earlier than BG. Furthermore, galf antigen concentrations of more than 120,000 times the serum cutoff value (0.5 ng/ml) can be measured, while BG concentrations reach a value only 978 times the serum cutoff value (60 pg/ml). During lytical growth, release of galf antigens further increased to a maximum level, which depended on pH. After that, the concentration of galf antigens stayed high (pH 7.4) or decreased to zero within 4 days (pH 5.0). In contrast to galf antigens, BG concentration decreased after 1 day of growth. The decrease of galf components seems to be due to the enzyme beta-galactofuranosidase, which is able to destroy galf epitopes and whose activity fluctuates in the culture filtrates in parallel with galf antigen concentration. Fungal DNA seems to be released only due to autolysis caused by nutrient limitation. In conclusion, several factors clearly influence the release of surrogate markers in vitro. These same factors might also play a role at the infection site of Aspergillus disease in humans.

Topics: Antigens, Fungal; Aspergillosis; Aspergillus fumigatus; beta-Glucans; Biomarkers; DNA, Fungal; Galactose; Glycoside Hydrolases; Humans

Two noninvasive diagnostic tests, (1-->3)-beta-D-glucan (BG) (Glucatell) and galactomannan (GM) (Platelia Aspergillus), were used retrospectively in a twice-weekly screening for the diagnosis of invasive aspergillosis (IA) in 40 treatment episodes (one hospital visit per patient) in 40 neutropenic adult patients at high risk for IA. Five proven IA cases, three probable IA cases, and three possible IA cases were diagnosed. Diagnostic levels of both BG and GM were detected in 100% of patients with proven IA cases and in 66% of patients with probable IA cases. The kinetics of both markers in patients with IA were similar. The sensitivity, specificity, and positive and negative predictive values for GM and BG were identical, namely, 87.5, 89.6, 70, and 96.3%, respectively. False-positive reactions occurred at a rate of 10.3% in both tests, but the patients showing false-positive results were different in each test. Both tests anticipated the clinical diagnosis, computed tomography abnormalities, and the initiation of antifungal therapy in most patients, but BG tended to become positive earlier than GM. A combination of the two tests improved the specificity (to 100%) and positive predictive value (to 100%) of each individual test without affecting the sensitivity and negative predictive values. In conclusion, BG and GM detection are useful tests for the diagnosis of IA in high-risk hematological patients, but a combination of the two tests was very useful to identify false-positive reactions by each test.

Topics: Adolescent; Adult; Aged; Antifungal Agents; Aspergillosis; Aspergillus; beta-Glucans; Chromogenic Compounds; Female; Galactose; Humans; Male; Mannans; Middle Aged; Neutropenia; Predictive Value of Tests; Sensitivity and Specificity

To generate a vaccine to protect against a variety of human pathogenic fungi, we conjugated laminarin (Lam), a well-characterized but poorly immunogenic beta-glucan preparation from the brown alga Laminaria digitata, with the diphtheria toxoid CRM197, a carrier protein used in some glyco-conjugate bacterial vaccines. This Lam-CRM conjugate proved to be immunogenic and protective as immunoprophylactic vaccine against both systemic and mucosal (vaginal) infections by Candida albicans. Protection probably was mediated by anti-beta-glucan antibodies as demonstrated by passive transfer of protection to naive mice by the whole immune serum, the immune vaginal fluid, and the affinity-purified anti-beta-glucan IgG fractions, as well as by administration of a beta-glucan-directed IgG2b mAb. Passive protection was prevented by adsorption of antibodies on Candida cells or beta-glucan particles before transfer. Anti-beta-glucan antibodies bound to C. albicans hyphae and inhibited their growth in vitro in the absence of immune-effector cells. Remarkably, Lam-CRM-vaccinated mice also were protected from a lethal challenge with conidia of Aspergillus fumigatus, and their serum also bound to and markedly inhibited the growth of A. fumigatus hyphae. Thus, this novel conjugate vaccine can efficiently immunize and protect against two major fungal pathogens by mechanisms that may include direct antifungal properties of anti-beta-glucan antibodies.

Topics: Analysis of Variance; Animals; Antibodies, Monoclonal; Aspergillosis; Aspergillus fumigatus; Bacterial Proteins; beta-Glucans; Candida albicans; Candidiasis, Vulvovaginal; Female; Fungal Vaccines; Glucans; Magnetic Resonance Spectroscopy; Mice; Mice, Mutant Strains; Polysaccharides; Rats; Rats, Wistar; Serologic Tests; Vaccines, Conjugate

The establishment of an optimal noninvasive method for diagnosing invasive aspergillosis (IA) is needed to improve the management of this life-threatening infection in patients with hematological disorders, and a number of noninvasive tests for IA that target different fungal components, including galactomannan, (1-->3)-beta-d-glucan (BDG), and Aspergillus DNA, have been developed. In this study, we prospectively evaluated the diagnostic potential of three noninvasive tests for IA that were used in a weekly screening strategy: the double-sandwich enzyme-linked immunosorbent assay (ELISA) for galactomannan (Platelia Aspergillus), a real-time PCR assay for Aspergillus DNA (GeniQ-Asper), and an assay for BDG (beta-glucan Wako). We analyzed 149 consecutive treatment episodes in 96 patients with hematological disorders who were at high risk for IA and diagnosed 9 proven IA cases, 2 probable IA cases, and 13 possible invasive fugal infections. In a receiver-operating characteristic (ROC) analysis, the area under the ROC curve was greatest for ELISA, using two consecutive positive results (0.97; P = 0.036 for ELISA versus PCR, P = 0.055 for ELISA versus BDG). Based on the ROC curve, the cutoff for the ELISA could be reduced to an optical density index (O.D.I.) of 0.6. With the use of this cutoff for ELISA and cutoffs for PCR and BDG that give a comparable level of specificity, the sensitivity/specificity/positive predictive value/negative predictive value of the ELISA and the PCR and BDG tests were 1.00/0.93/0.55/1.00, 0.55/0.93/0.40/0.96, and 0.55/0.93/0.40/0.96, respectively. In conclusion, among these weekly screening tests for IA, the double-sandwich ELISA test was the most sensitive at predicting the diagnosis of IA in high-risk patients with hematological disorders, using a reduced cutoff of 0.6 O.D.I.

Topics: Adolescent; Adult; Aged; Aspergillosis; beta-Glucans; Enzyme-Linked Immunosorbent Assay; Female; Galactose; Glucans; Hematologic Diseases; Humans; Male; Mannans; Middle Aged; Polymerase Chain Reaction; Prospective Studies; ROC Curve; Sensitivity and Specificity

We analyzed the performance of (1, 3)-Beta-D-glucan (measurement by the alkaline-kinetic chromogenic Limulus method (FUNGITEC G test-MK, Fungitec) and the kinetic turbidimetric Limulus method [Beta-Glucan test WAKO, Wako]) and we carried out Aspergillus galactomannan antigen detection (enzyme-linked immunosorbent assay, ELISA test) for the early diagnosis of invasive aspergillosis in patients with hematological diseases at the time of febrile episodes of unknown origin that did not respond to antibacterial therapy for more than 3 days. During a one-year period (April 2002 to March 2003), a total of 69 febrile episodes in 58 patients were studied; 8 cases of invasive aspergillosis were diagnosed according to the definition of the European Organization for Research and Treatment of Cancer/Mycosis Study Group, and 61 cases were found to be non-mycotic diseases. Based on the analysis of 69 results with confirmed disease status, the overall performance of the Fungitec, the Wako, and the ELISA test were as follows: sensitivity was 0.88, 0.63, and 0.50, respectively, whereas the specificity was 0.85, 0.98, and 1.0, respectively. Moreover, there was a strong relationship between the log-transformed values of the (1, 3)-Beta-D-glucan levels measured by the two methods (r = 0.92 [95%CI, 0.89-0.94] ; p<0.001). For the statistical analysis of these serological tests a receiver operating characteristic curve (ROC) was used, as well as the resulting area under the ROC curve (ROC AUC). The ROC AUC and the cut-off values that gave the highest accuracy were as follows: 0.92, 24.9 pg/ml for the Fungitec, 0.84, 7.3 pg/ml for the Wako, and 0.89, 0.9 COI for the ELISA test, respectively. In conclusion, these results indicate that both of the two (1, 3)-Beta-D-glucan measurement approaches served equally well as surveillance tools for determining the extent of invasive aspergillosis; in addition, the log-transformed value of these tests can be used for comparison. Moreover, the ELISA test was found to have clinical utility, both as a surveillance and as a diagnostic tool when invasive aspergillosis was suspected. It should be noted that the galactomannan assay had sensitivity-related limitations; lowering the cut-off value is expected to increase the diagnostic value for use in cases of invasive aspergillosis.

Topics: Adult; Aged; Aged, 80 and over; Antigens, Fungal; Aspergillosis; beta-Glucans; Female; Galactose; Glucans; Hematologic Neoplasms; Humans; Limulus Test; Lung Diseases, Fungal; Male; Mannans; Middle Aged; Sensitivity and Specificity

Topics: Aged; Aged, 80 and over; Aspergillosis; beta-Glucans; Glucans; Humans; Lung Diseases, Fungal; Male; Pulmonary Disease, Chronic Obstructive

We developed a new quantitative system for diagnosis of invasive pulmonary aspergillosis (IPA) using real-time automated polymerase chain reaction (PCR). Intra-assay and interassay precision rates for in vitro examination were 2.53% and 2.20%, respectively, and the linearity of this assay was obtained when there were >20 copies/well. We examined 323 samples taken from 122 patients with hematological malignancies, including 33 patients with IPA and 89 control patients. Blood samples were subjected to PCR antigen detection methods, using enzyme-linked immunosorbent assay (ELISA) and determination of plasma (1-->3)-beta-D-glucan (BDG) concentration. The sensitivities of PCR, ELISA, and BDG measurement for diagnosis of IPA were 79%, 58%, and 67%, respectively; the specificities were 92%, 97%, and 84%. Positive findings on PCR preceded those of computed tomography by -0.3+/-6.6 days, those of BDG measurement by 6.5+/-4.9 days, and those of ELISA by 2.8+/-4.1 days. Real-time PCR was sensitive for IPA diagnosis, and quantitation was accurate.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Aspergillosis; Aspergillus; beta-Glucans; Enzyme-Linked Immunosorbent Assay; Female; Fever; Glucans; Humans; Lung Diseases, Fungal; Male; Middle Aged; Polymerase Chain Reaction; Reproducibility of Results; Sensitivity and Specificity; Time Factors; Tomography, X-Ray Computed

Blood and radiologic tests are frequently used for diagnosis of invasive pulmonary aspergillosis, but it remains unknown which is more useful for its early diagnosis. Aim of the study was to compare usefulness of computed tomographic (CT) scan of chest, latex agglutination (LA) test and determination of plasma (1-->3)-beta-D-glucan (BDG) levels for early diagnosis of invasive pulmonary aspergillosis (IPA).. We treated 215 consecutive patients who underwent cytotoxic chemotherapy. From initiation of chemotherapy until death or discharge, blood samples were taken weekly and subjected to LA and BDG tests. We performed chest CT scans when patients had any signs of pulmonary infection or an antibiotic-resistant fever.. Of the 215 patients, 30 (14. 0%) were diagnosed as having IPA. In sixteen cases the diagnosis was definite and in 14 it was suspected. In patient-based analysis, sensitivities of LA and BDG were 44% and 63%, respectively. Sensitivity tended to be lower in patients with IPA localized to the lung than those with disseminated invasive aspergillosis. Specificities were 93% and 74%, respectively. Either a halo or an air-crescent was observed in 7 of the 16 patients with IPA, and all of the IPA patients showed some abnormal signs on chest CT scans. On average, CT scan signs preceded a positive LA test by 7.1 days and a positive BDG assay by 11.5 days. In 6 of the 11 patients who became positive for either LA or BDG assay, CT scan signs preceded the positive results by more than seven days.. Chest CT scan is more beneficial than the blood tests and X-ray for early diagnosis of IPA.

Topics: Adjuvants, Immunologic; Adolescent; Adult; Aged; Aged, 80 and over; Anti-Infective Agents; Antineoplastic Combined Chemotherapy Protocols; Aspergillosis; beta-Glucans; Diagnostic Techniques, Respiratory System; Glucans; Humans; Latex Fixation Tests; Lung Diseases, Fungal; Middle Aged; Prospective Studies; Radiography, Thoracic; Sensitivity and Specificity; Tomography, X-Ray Computed

Clinical evaluation was retrospectively made of the results of serological diagnostic methods using plasma and/or sera of patients for the diagnosis of aspergillosis, candidosis, and pneumocystosis. Specimens were drawn from 8 patients with invasive aspergillosis, 3 with aspergilloma, 9 with candidosis, 4 with pneumocystosis, and 15 with no fungal infections. In invasive aspergillosis, the sensitivities of the (1-3)-beta-D-glucan measurement test using chromogenic and turbidimetric methods were 78.6% and 82.1%, with specificities of 75% and 87.5%, respectively. The sensitivity of the Pastorex Aspergillus test for invasive aspergillosis was 16.7%, with a specificity of 92.3%. In candidosis, the sensitivities of the (1-3)-bata-D-glucan test using the above two methods were 84.2% and 100%, with specificities of 75% and 87.5%, respectively. The sensitivity of the CAND-TEC test and the Pastorex Candida test for candidosis were 68.8% and 16.7%, with specificities of 57.1% and 100%, respectively. These results indicate that the (1-3)-bata-D-glucan measurement methods are more reliable in clinical application than the other antigen detection methods, but they still lack efficiency in differentiating fungal infections such as aspergillosis, candidosis and pneumocystosis. For a more exact diagnosis of systemic fungal infections, detailed studies on the clinical symptoms are considered essential.

Topics: Aspergillosis; beta-Glucans; Biomarkers; Candidiasis; Glucans; Humans; Pneumocystis Infections; Sensitivity and Specificity

We compared PCR, galactomannan detection assay using a latex agglutination test and (1-->3)-beta-D-glucan detection assay in detecting infection in rats experimentally infected with Aspergillus fumigatus. On day 2 after inoculation, (1-->3)-beta-D-glucan and nested PCR were positive for 80%, while galactomannan detection assay was positive for 60%. In addition, the positive result of nested PCR (87.5%) was higher than those of galactomannan detection assay (75%) and (1-->3)-beta-D-glucan (71.4%) on day 3 after inoculation. The sensitivity of nested PCR was superior to those of galactomannan detection assay and (1-->3)-beta-D-glucan detection assay. The three diagnostic tests were compared with histopathological findings, and the sensitivity of three diagnostic tests was correlated with histopathological changes. In addition, the elevated levels of (1-->3)-beta-D-glucan paralleled the development and progression of pulmonary aspergillosis. Our results indicate that a combination of two or three of these tests seems to provide a rapid diagnosis of invasive aspergillosis and assist in the evaluation of the development and severity of invasive aspergillosis.

Topics: Animals; Aspergillosis; Aspergillus fumigatus; beta-Glucans; Galactose; Glucans; Latex Fixation Tests; Lung Diseases, Fungal; Male; Mannans; Polymerase Chain Reaction; Rats; Rats, Sprague-Dawley

The present multicentre clinical study was conducted to assess the clinical utility of a new diagnostic method for deep mycosis in which (1-->3)-beta-D-glucan, a fungal cell wall component existing in plasma, was quantitatively measured by the kinetic turbidimetric Limulus test (WB003). Plasma (1-->3)-beta-D-glucan concentrations were 0.57 +/- 0.10 microgram/l in 92 healthy subjects and 0.62 +/- 0.32 microgram/l in 26 patients with non-mycotic diseases (disease control group). In comparison with these healthy subjects and patients with non-mycotic diseases, patients with mycosis had significantly higher plasma (1-->3)-beta-D-glucan concentrations: 19.63 +/- 73.28 micrograms/l in 12 patients with candidaemia, 11.28 +/- 21.42 micrograms/l in 7 patients with urinary Candida infection, 4.84 +/- 12.71 micrograms/l in 5 patients with pulmonary candidiasis, and 12.21 +/- 31.31 micrograms/l in 4 patients with invasive pulmonary aspergillosis. On the statistical analysis of these data, a cut-off value was set at 1.0 microgram/l. Using this cut-off value, 3 patients with pulmonary cryptococcosis and 4 patients (4/6) with pulmonary aspergilloma were all negative with low plasma (1-->3-beta-D-glucan levels. The test WB003 provided equivalent or higher efficiency of diagnosis of candidiasis and aspergillosis, in comparison with commercially available antigen detection kits, demonstrating its utility as a diagnostic reagent. It may also be useful in assessing therapeutic effectiveness when used periodically after treatment.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Aspergillosis; beta-Glucans; Candidiasis; Cryptococcosis; Diagnostic Errors; Evaluation Studies as Topic; Female; Fungemia; Glucans; Humans; Kinetics; Limulus Test; Lung Diseases, Fungal; Male; Middle Aged; Mycoses; Nephelometry and Turbidimetry; Time Factors; Urinary Tract Infections

The value of the measurement of (1-->3)-beta-D-glucan, a major and common cell wall constituent of fungi, for diagnosing pulmonary aspergillosis was assessed in comparison with that of conventional examinations. The concentrations of (1-->3)-beta-D-glucan in sera was elevated in 7 out of 8 patients with active aspergillosis, but not in cases without active diseases, except for one sample. Further, the concentrations well reflected the activity of the aspergillosis in each case. Regarding conventional examinations, with the immunodiffusion test it was difficult to detect the present activity of the disease. The radioallergosorbent test was useful for diagnosing bronchopulmonary aspergillosis, but not for other types of aspergillosis. The Aspergillus-specific component, galactomannan, was insensitive and the enzyme-linked immunosorbent assay gave highly variable results. Thus, although the assessment of the specificity of the assay is still necessary, compared with other tests, the assay of (1-->3)-beta-D-glucan has the advantage of diagnosing pulmonary aspergillosis and also of assessing the disease activity.

Topics: Antibodies, Fungal; Aspergillosis; Aspergillosis, Allergic Bronchopulmonary; Aspergillus; beta-Glucans; Enzyme-Linked Immunosorbent Assay; Glucans; Humans; Lung Diseases; Lung Diseases, Fungal; Necrosis; Radioallergosorbent Test

The G test containing factor G, fractioned from the Limulus lysate, was used to detect (1-3)-beta-D-glucan in a rat model of aspergillosis. Aspergillus fumigatus strain MF-13, 1 x 10(4) conidia, were inoculated transtracheally into rats treated with cortisone acetate (100 mg/kg) and fed a low-protein (8%) diet. Increased serum (1-3)-beta-D-glucan was found on the sixth day after inoculation in concentrations of 370 +/- 178 pg/ml (mean +/- SD) in untreated controls, and 154 +/- 43 pg/ml in rats treated with 0.5 mg/kg of amphotericin B. On day 11 (1-3)-beta-D-glucan concentrations were 2,590 +/- 2,940 pg/ml and 448 +/- 442 pg/ml, respectively. The elevation in levels of (1-3)-beta-D-glucan increased in correlation with the elevation of galactomannan antigen titers; (1-3)-beta-D-glucan is thus measurable during experimental aspergillosis in rats.

Topics: Amphotericin B; Animals; Aspergillosis; Aspergillus fumigatus; beta-Glucans; Disease Models, Animal; Galactose; Glucans; Horseshoe Crabs; Lung; Male; Mannans; Rats; Rats, Sprague-Dawley

(1-->3)-beta-D-glucan is a characteristic fungal cell-wall constituent. To assess the clinical usefulness of this glucan in screening for invasive fungal infection or fungal febrile episodes, we measured the plasma concentration at the time of routine blood culture in 202 febrile episodes by means of factor G, a horseshoe-crab coagulation enzyme that is extremely sensitive to this polysaccharide. With a plasma cut-off value of 20 pg/mL, 37 of 41 episodes of definite fungal infections (confirmed at necropsy or by microbiology) had positive results (sensitivity 90%). All of 59 episodes of non-fungal infections, tumour fever, or collagen diseases had concentrations below the cut-off value (specificity 100%). Of 102 episodes of fever of unknown origin, 26 had plasma glucan concentrations of more than 20 pg/mL. With those 102 cases taken as non-fungal infections, the positive predictive value of the test was estimated as 59% (37/63), the negative predictive value as 97% (135/139), and the efficiency as 85% (172/202). The positive predictive value should improve if there were a sensitive gold standard that could discriminate fungal from non-fungal infections. Causative fungi included candida, aspergillus, cryptococcus, and trichosporon. Determination of plasma (1-->3)-beta-D-glucan with factor G is a highly sensitive and specific test for invasive deep mycosis and fungal febrile episodes, and will substantially benefit immunocompromised patients.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Aspergillosis; beta-Glucans; Blood Coagulation Factors; Candidiasis; Child; Child, Preschool; Female; Fever; Fungemia; Glucans; Humans; Male; Middle Aged; Mycoses; Sensitivity and Specificity; Serine Endopeptidases

Topics: Acute Disease; Animals; Aspergillosis; beta-Glucans; Biomarkers; Glucans; Lung; Lung Diseases, Fungal; Rats

(1-3)-beta-D-Glucan (beta-glucan) is a major structural component of fungi. The G test is a direct method to detect beta-glucan using fractionated (1-3)-beta-D-glucan-sensitive component, factor G, eluted from the limulus lysate. Previously, we reported that the G test is a more sensitive method than the mannan detection assay for the serological diagnosis of Candida infection. In this study, we discuss beta-glucanemia in patients with pulmonary aspergillosis and cryptococcosis. The concentration of beta-glucan was less than 10 pg/ml in 9 of 10 cases of pulmonary cryptococcosis, except for one case receiving hemodialysis (16.5 pg/ml). beta-Glucan increased in 3 cases of invasive pulmonary aspergillosis (27-937 pg/ml). Galactomannan antigen was positive in all of those cases. In 8 cases of aspergilloma, which showed fungus ball on roentgenogram, the mean concentration of beta-glucan was 67.1 +/- 92.7 pg/ml. Two of 8 cases were positive for galactomannan antigen. One of three cases of PAIC (productive aspergilloma on the inner wall of a cavity) and one case of chronic necrotizing pulmonary aspergillosis showed slightly increased levels of beta-glucan and positive results of galactomannan antigen test.

Topics: Adult; Aged; Antigens, Fungal; Aspergillosis; beta-Glucans; Child; Cryptococcosis; Female; Galactose; Glucans; Humans; Lung Diseases, Fungal; Male; Mannans; Middle Aged