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The fungal cell wall is necessary for survival as it serves a barrier for physical protection. Therefore, glycosyltransferases responsible for the synthesis of cell wall polysaccharides may be suitable targets for drug development. Mannose is a monosaccharide that is commonly found in sugar chains in the walls of fungi. Mannose residues are present in fungal-type galactomannan, O -glycans, N -glycans, glycosylphosphatidylinositol anchors, and glycosyl inositol phosphorylceramides in Aspergillus fumigatus. Three genes that are homologous to α-(1 → 2)-mannosyltransferase genes and belong to the glycosyltransferase family 15 were found in the A. fumigatus strain, Af293/A1163, genome: cmsA / ktr4 , cmsB / ktr7 , and mnt1. It is reported that the mutant ∆ mnt1 strain exhibited a wide range of properties that included high temperature and drug sensitivity, reduced conidia formation, leakage at the hyphal tips, and attenuation of virulence. However, it is unclear whether Mnt1 is a bona fide α-(1 → 2)-mannosyltransferase and which mannose residues are synthesized by Mnt1 in vivo. In this study, we elucidated the structure of the Mnt1 reaction product, the structure of O -glycan in the Δ mnt1 strain. In addition, the length of N -glycans attached to invertase was evaluated in the Δ mnt1 strain. The results indicated that Mnt1 functioned as an α-(1 → 2)-mannosyltransferase involved in the elongation of N -glycans and synthesis of the second mannose residue of O -glycans. The widespread abnormal phenotype caused by the disruption of the mnt1 gene is the combined result of the loss of mannose residues from O -glycans and N -glycans. We also clarified the enzymatic properties and substrate specificity of Mnt1 based on its predicted protein structure. [ABSTRACT FROM AUTHOR]

In this study, a recombinant Aspergillus sojae beta (β)‐mannanase produced from carob extract in the microparticle‐enhanced bioreactor was applied to locust bean gum (LBG) and guar gum (GG) as hydrocolloids. The effects of enzyme amount (EA), temperature (T), and gum concentration (GC) on mannooligosaccharides (MOSs) enzymatic fabrication were examined using Box–Behnken response surface methodology. Under optimized conditions (GC = 1%, T = 40°C, EA = 7.5 ml, and incubation time = 10 min for LBG and GC = 0.75%, T = 50°C, EA = 7.5 ml, and incubation time = 35 min for GG), the M2, M3, M4, M5, and M6 fabrications from LBG were 455.2, 801.1, 101.1, 346.9, and 1,592.3 ppm, while the M2, M3, and M6 concentrations from GG were 92.85, 220.99, and 1,882.54 ppm, respectively. The M6 was the most dominant MOS from both gums. Consequently, LBG and GG can be potential sources of MOS production. It has been observed that MOS productions can be enhanced by optimizing β‐mannanase enzyme treatment conditions. Practical applications: In recent years, MOS has gained attention due to its prebiotic efficacy that prevents infections by regulating the intestinal microbiota and reducing the risk of various chronic degenerative diseases. β‐mannanases are extracellular enzymes that hydrolyze 1,4‐β‐D mannosidic bonds in mannan, galactomannan, glucomannan, and galactoglucomannans. Locust bean gum (LBG) and guar gum (GG) can be used in the production of mannooligosaccharides (MOS) which is well known to have prebiotic effects. Both hydrocolloid substances are rich in point of mannans, galactomannans, glucomannans, and galactoglucomannans. Therefore, these compounds can be hydrolyzed to produce MOS from different hydrocolloids using β‐mannanases. In this study, to produce MOS from gums, β‐mannanase obtained from Aspergillus sojae fermentation was used. The results showed that LBG and GG could be a potential source of MOS production. It has been observed that higher amounts of MOS production can be achieved by optimizing β‐mannanase enzyme treatment conditions. [ABSTRACT FROM AUTHOR]

Humoral immune components have been individually studied in the context of interaction of host with Aspergillus fumigatus , a major airborne fungal pathogen. However, a global view of the multitude and complex nature of humoral immune components is needed to bring new insight into host- Aspergillus interaction. Therefore, we undertook comparative proteomic analysis of the bronchoalveolar lavage fluid collected from individuals infected or colonized with A. fumigatus versus controls, to identify those alveolar humoral components affected upon A. fumigatus infection. Complement proteins C1q, C8 beta-chain, factor-H, ficolin-1, ficolin-2, mannan binding lectin serine peptidase 2, pentraxin-3 and the surfactant protein-D were identified as the major humoral immune components affected by A. fumigatus infection and colonization. Based on this observation, we hypothesize that crosstalk between these humoral components is essential during host- Aspergillus interaction giving new specific leads to study for better understanding the pathogenesis. Furthermore, the affected humoral components could be potential diagnostic markers of A. fumigatus infection or colonization. [ABSTRACT FROM AUTHOR]

Copyright of Croatian Journal of Infection / Infektoloski Glasnik is the property of Croatian Society for Infectious Diseases and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Data on biomarker-assisted diagnosis of invasive aspergillosis (IA) in pediatric patients is scarce. Therefore, we conducted a cohort study over two years including 404 serum specimens of 26 pediatric patients after allogeneic hematopoietic stem cell transplantation (alloSCT). Sera were tested prospectively twice weekly for Aspergillus-specific DNA, galactomannan (GM), and retrospectively for (1→3)-β-D-glucan (BDG). Three probable IA and two possible invasive fungal disease (IFD) cases were identified using the European Organization for Research and Treatment of Cancer and the Mycoses Study Group (EORTC/MSGERC) 2019 consensus definitions. Sensitivity and specificity for diagnosis of probable IA and possible IFD was 80% (95% confidential interval (CI): 28–99%) and 55% (95% CI: 32–77%) for BDG, 40% (95% CI: 5–85%) and 100% (95% CI: 83–100%) for GM, and 60% (95% CI: 15–95%) and 95% (95% CI: 75–100%) for Aspergillus-specific real-time PCR. However, sensitivities have to be interpreted with great caution due to the limited number of IA cases. Interestingly, the low specificity of BDG was largely caused by false-positive BDG results that clustered around the date of alloSCT. The following strategies were able to increase BDG specificity: two consecutive positive BDG tests for diagnosis (specificity 80% (95% CI: 56–94%)); using an optimized cutoff value of 306 pg/mL (specificity 90% (95% CI: 68–99%)) and testing BDG only after the acute posttransplant phase. In summary, BDG can help to diagnose IA in pediatric alloSCT recipients. However, due to the poor specificity either an increased cutoff value should be utilized or BDG results should be confirmed by an alternative Aspergillus assay. [ABSTRACT FROM AUTHOR]

Rationale: Invasive tracheobronchial aspergillosis (ITBA) is an uncommon but severe clinical form of invasive pulmonary aspergillosis in which the fungal infection is entirely or predominantly confined to the tracheobronchial tree.Objectives: To analyze the diagnostic and prognostic differences between tracheobronchial aspergillosis and pulmonary aspergillosis without tracheobronchial lesions among patients admitted to the ICU with severe influenza.Methods: This retrospective, observational study included critically ill patients with influenza associated with pulmonary aspergillosis from three hospital ICUs between 2010 and 2019. Patient characteristics and clinical and mycologic data at admission and during ICU stay were collected in a database to evaluate variables in the two groups.Measurements and Main Results: Thirty-five patients admitted to the ICU with severe influenza and pulmonary aspergillosis were included. Ten patients were included in the group with ITBA (n = 10 of 35; 28.6%), and 25 patients were included in the group without ITBA. The group with ITBA comprised more patients with active smoking, diabetes mellitus, and higher severity scores (Simplified Acute Physiology Score II). Ninety-day mortality rates in the groups with and without ITBA were 90% and 44%, respectively (P = 0.02). Moreover, significantly higher serum 1,3-β-d-glucan and galactomannan and BAL fluid galactomannan concentrations were observed in the group with ITBA compared with the group without ITBA (P < 0.0001, P = 0.003, and P = 0.008, respectively).Conclusions: ITBA was associated with higher severity scores, mortality, and serum and BAL fluid galactomannan and 1,3-β-d-glucan concentrations than invasive pulmonary aspergillosis without tracheobronchial lesions. ITBA should be systematically researched by bronchoscopic examination in ICU patients with concomitant pulmonary aspergillosis and influenza.Clinical trial registered with www.clinicaltrials.gov (NCT04077697). [ABSTRACT FROM AUTHOR]

Extensive advances in technology offer a vast variety of diagnostic methods that save time and costs, but identification of fungal species causing human infections remains challenging in developing countries. Since the echinocandins, antifungals widely used to treat invasive mycoses, are still unavailable in developing countries where a considerable number of problematic fungal species are present, rapid and reliable identification is of paramount importance. Unaffordability, large footprints, lack of skilled personnel, and high costs associated with maintenance and infrastructure are the main factors precluding the establishment of high-precision technologies that can replace inexpensive yet time-consuming and inaccurate phenotypic methods. In addition, point-of-care lateral flow assay tests are available for the diagnosis of Aspergillus and Cryptococcus and are highly relevant for developing countries. An Aspergillus galactomannan lateral flow assay is also now available. Real-time PCR remains difficult to standardize and is not widespread in countries with limited resources. Isothermal and conventional PCR-based amplification assays may be alternative solutions. The combination of real-time PCR and serological assays can significantly increase diagnostic efficiency. However, this approach is too expensive for medical institutions in developing countries. Further advances in next-generation sequencing and other innovative technologies such as clustered regularly interspaced short palindromic repeats (CRISPR)-based diagnostic tools may lead to efficient, alternate methods that can be used in point-of-care assays, which may supplement or replace some of the current technologies and improve the diagnostics of fungal infections in developing countries. [ABSTRACT FROM AUTHOR]

Objectives: The growing emergence of azole-resistant Aspergillus fumigatus strains worldwide is a major concern for current systemic antifungal treatment. Here we report antifungal activities of a novel inhaled triazole, PC1244, against a collection of multi-azole-resistant A. fumigatus strains.Methods: MICs of PC1244 were determined for A. fumigatus carrying TR34/L98H (n = 81), TR46/Y121F/T289A (n = 24), M220 (n = 6), G54 (n = 11), TR53 (n = 1), TR463/Y121F/T289A (n = 2), G448S (n = 1), G432C (n = 1) and P216S (n = 1) resistance alleles originating from either India, the Netherlands or France. The effects of PC1244 were confirmed in an in vitro model of the human alveolus and in vivo in temporarily neutropenic, immunocompromised mice.Results: PC1244 exhibited potent inhibition [geometric mean MIC (range), 1.0 mg/L (0.125 to >8 mg/L)] of growth of A. fumigatus strains carrying cyp51A gene mutations, showing much greater potency than voriconazole [15 mg/L (0.5 to >16 mg/L)], and an effect similar to those on other azole-susceptible Aspergillus spp. (Aspergillus flavus, Aspergillus terreus, Aspergillus tubingensis, Aspergillus nidulans, Aspergillus niger, Aspergillus nomius, Aspergillus tamarii) (0.18-1 mg/L). In TR34/L98H and TR46/Y121F/T289A A. fumigatus-infected in vitro human alveolus models, PC1244 achieved superior inhibition (IC50, 0.25 and 0.34 mg/L, respectively) compared with that of voriconazole (IC90, >3 mg/L and >10 mg/L, respectively). In vivo, once-daily intranasal administration of PC1244 (0.56-70 μg/mouse) to the A. fumigatus (AF91 with M220V)-infected mice reduced pulmonary fungal load and serum galactomannan more than intranasal posaconazole.Conclusions: PC1244 has the potential to become a novel topical treatment of azole-resistant pulmonary aspergillosis. [ABSTRACT FROM AUTHOR]

Aspergillus fumigatus and A. flavus are the fungal pathogens responsible for most cases of invasive aspergillosis (IA). Early detection of the circulating antigen galactomannan (GM) in serum allows the prompt application of effective antifungal therapy, thus improving the survival rate of IA patients. However, the use of monoclonal antibodies (mAbs) for the diagnosis of IA is often associated with false positives due to cross-reaction with bacterial polysaccharides. More specific antibodies are therefore needed. Here we describe the characterization of the Aspergillus -specific mAb AP3 (IgG1κ), including the precise identification of its corresponding antigen. The antibody was generated using A. parasiticus cell wall fragments and was shown to bind several Aspergillus species. Immunofluorescence microscopy revealed that AP3 binds a cell wall antigen, but immunoprecipitation and enzyme-linked immunosorbent assays showed that the antigen is also secreted into the culture medium. The inability of AP3 to bind the A. fumigatus galactofuranose (Gal f)-deficient mutant Δ glfA confirmed that Gal f residues are part of the epitope. Several lines of evidence strongly indicated that AP3 recognizes the Gal f residues of O -linked glycans on Aspergillus proteins. Glycoarray analysis revealed that AP3 recognizes oligo-[β-D-Gal f -1,5] sequences containing four or more residues with longer chains more efficiently. We also showed that AP3 captures GM in serum, suggesting it may be useful as a diagnostic tool for patients with IA. [ABSTRACT FROM AUTHOR]

There have been conflicting reports of false positive galactomannan assay results in patients with systemic cryptococcosis. We sought to determine the frequency of GM positivity in patients with pulmonary cryptococcosis and confirm the source of this cross-reactivity in vitro. We conducted a retrospective study to elucidate the rate of galactomannan (GM) false positivity and cause in a cohort of 29 patients with pulmonary cryptococcal disease. The production of GM cross-reacting substances by clinical isolates and laboratory isolates of C. neoformans was tested in vitro. The mean serum GM index (Platelia Aspergillus) in patients with pulmonary cryptococcosis was 1.06, with 16 (55.2%) of patients having values above the positive cutoff value of 0.5. GM index values significantly decreased after treatment of cryptococcosis. There was no significant correlation between galactomannan and cryptococcal glucuronoxylomannan antigen (Eiken Latex test) results. Culture supernatants from clinical isolates and wild-type C. neoformans did not react in the GM assay; however, growth in the presence of 6% sodium chloride induced the production of cross-reacting GM antigens in culture supernatants from clinical isolates, wild type and a glucuronoxylomannan-deficient mutant of C. neoformans, but not in culture supernatants from a galactoxylomannan-deficient strain. Our results support the cross-reactivity of cryptococcal galactoxylomannan with the serum GM assay in vitro and in patients with pulmonary cryptococcal infection. [ABSTRACT FROM AUTHOR]

Summary: Background: We compared new Aspergillus Galactomannan Lateral Flow Assay with the newly formatted Aspergillus‐specific Lateral Flow device tests for the diagnosis of invasive pulmonary aspergillosis (IPA) in non‐neutropenic patients. Methods: We performed both tests in 82 bronchoalveolar lavage fluid samples from 82 patients at risk for IPA but without underlying haematologic malignancy. Samples were collected between September 2016 and September 2018 at the University of California San Diego, United States. IPA was classified following two published consensus criteria. Results: Classification of cases varied widely between the two consensus criteria. When using criteria established for the intensive care unit, 26/82 patients (32%) met criteria for proven or putative IPA. Both point‐of‐care assays showed sensitivities ranging between 58% and 69%, with specificities between 68% and 75%. Sensitivity increased up to 81% when both tests were combined. Conclusion: The study outlines the need for updated, unified and more broadly applicable consensus definitions for classifying IPA in non‐neutropenic patients, a work that is currently in progress. Both point‐of‐care tests showed comparable performance, with sensitivities and specificities in the 60%‐70% range when used alone and increasing to 80% when used in combination. The new point‐of‐care tests may serve a role at the bedside in those with clinical suspicion of IPA. [ABSTRACT FROM AUTHOR]

Summary: Objectives: Bronchoalveolar lavage galactomannan (BAL‐GM) is a mycological criterion for diagnosis of probable invasive aspergillosis (IA) per European Organization for Research and Treatment of Cancer/Mycoses Study Group (EORT‐MSG) consensus criteria, but its real‐world positive predictive value (PPV) has not been well‐studied. Our aim was to estimate the PPV of BAL‐GM in a contemporary cohort of patients with positive BAL‐GM. Methods: We identified consecutive patients with ≥1 positive BAL‐GM value (index ≥ 0.5) at Brigham and Women's Hospital from 11/2009 to 3/2016. We classified patients as having no, possible, probable, or proven IA, excluding BAL‐GM as mycological criterion. Results: We studied 134 patients: 54% had hematologic malignancy (HM), and 10% were solid organ transplant (SOT) recipients. A total of 42% of positive (≥0.5) BAL‐GM results were falsely positive (PPV 58%). The number of probable IA cases was increased by 23% using positive BAL‐GM as mycologic criterion alone. PPV was higher in patients with HM or SOT (P < 0.001) and with use of higher thresholds for positivity (BAL‐GM ≥ 1 vs 1‐0.8 vs 0.8‐0.5: P = 0.002). Conclusions: 42% of positive BAL‐GM values were falsely positive. We propose a critical reassessment of BAL‐GM cutoff values in different patient populations. Accurate noninvasive tests for diagnosis of IA are urgently needed. [ABSTRACT FROM AUTHOR]

Non-culture-based diagnostics have been developed to help establish an early diagnosis of invasive fungal infection. Studies have shown that these tests can significantly impact the diagnosis of infection in high risk patients. Aspergillus galactomannan EIA testing is well-recognized as an important adjunct to the diagnosis of invasive aspergillosis and can be detected in serum, bronchoalveolar lavage and other fluids. Galactomannan testing used along with PCR testing has been shown to be effective when integrated into care paths for high risk patients for both diagnoses and as a surrogate marker for outcome when used in serial testing. Beta-D-glucan assays are non-specific for several fungal genera including Aspergillus and Candida and in high risk patients have been an important tool to augment the diagnosis. Lateral flow technology using monoclonal antibodies to Aspergillus are available that allow rapid testing of clinical samples. While standard PCR for Candida remains investigational, T2 magnetic resonance allows for the rapid diagnosis of Candida species from blood cultures. Aspergillus PCR has been extensively validated with standardized approaches established for these methods and will be included in the diagnostic criteria in the revised European Organization for Research and Treatment of Cancer/Mycoses Study Group (EORTC-MSG) definitions. Finally, these non-culture-based tests can be used in combination to significantly increase the detection of invasive mycoses with the ultimate aim of establishing an early diagnosis of infection. [ABSTRACT FROM AUTHOR]

Copyright of Revista Española de Quimioterapia is the property of Sociedad Espanola de Quimioterapia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Galactomannan (GM), 1,3-β-D-glucan (BDG) and aspergillus-lateral flow device (LFD) are recognized as diagnostic tools for invasive aspergillosis (IA). The combined performance of these assays, however, is inconsistent in various studies. We undertook a meta-analysis of 13 studies involving 1513 patients to evaluate the utility of GM in combination with BDG or LFD for diagnosing IA. The pooled SEN, SPE, PLR, NLR and diagnostic odds ratio (DOR) were calculated and constructed to summarize the overall combined performance. Combining both positive results of GM and BDG assays leaded to the pooled SEN 0.49 (95%CI 0.27–0.72), SPE 0.98 (95%CI 0.94–1.00), PLR 31.68 (95%CI 5.36–187.37), NLR 0.52 (95%CI 0.32–0.84) and DOR 61.23 (95%CI 6.96–538.90). Comparing with GM and BDG assays, both positive results of GM and LFD leaded to high SEN, similar SPE, low PLR and NLR. At least one positive result of GM or LFD conferred great SEN 0.93 and low NLR 0.08. Both positive results of GM and BDG or LFD assay were in favor of confirming the existence of IA. And both negative results of GM and LFD were beneficial to rule out IA. Further studies with sufficient sample size should focus on the diagnostic performance and cost-effectiveness of these combined tests in clinical setting. Highlights • The GM combined with BDG or LFD test is beneficial for the diagnosis of IA. • Both positive results of GM and BDG assays or LFD were in favor of confirming the existence of IA. • Both negative results of GM and LFD were beneficial to rule out the possibility of IA. [ABSTRACT FROM AUTHOR]

Summary: Background: Screening for Aspergillus (Asp‐AG) and Candida antigen (Ca‐AG) with immunoassays is established for stem cell recipients at high risk for invasive fungal infections (IFI). While parenteral nutrition (PN) will be applied in case of complications leading to insufficient alimentation, piperacillin‐tazobactam (TZP) is started at the onset of febrile neutropenia. Objectives: The aim of this study was to investigate drug‐laboratory interactions between PN and TZP and both immunoassays which could affect the specificity of the assays and lead to the false assumption of an IFI. Methods: Batches of TZP and PN were tested with both assays in vitro. In total, 380 samples of 83 batches were analysed. Results: None of the examined preparations were tested positive with Asp‐AG assay. Measurable amounts of Ca‐AG were detected in a lipid emulsion, two different trace element supplements, a fat‐soluble vitamin preparation and all tested brands of TZP. Conclusions: We conclude that false positivity of Asp‐AG assay due to TZP and PN does not occur. Cross reactions with Ca‐AG assay have been detected in some preparations. The in vivo relevance of Ca‐AG positivity has to be reviewed in further studies considering an effect of dilution. Physicians should be aware of a possible cross reaction with Ca‐AG assays which could lead to false‐positive results. [ABSTRACT FROM AUTHOR]

Background The optimal strategy for prevention of invasive fungal infections in lung transplant recipients remains undetermined. We studied strategies based on bronchoalveolar lavage fungal culture and galactomannan for prevention of invasive aspergillosis in lung transplant recipients. Methods Consecutive lung transplant recipients were evaluated during the period January 2010 to September 2014. Rates of invasive aspergillosis and all-cause mortality were recorded at 1 year. Criteria established by the International Society for Heart and Lung Transplantation were used to define invasive fungal infections. Multivariate Cox regression analyses were performed to assess the outcomes of mortality and invasive aspergillosis. Results A total of 519 lung transplant recipients with 3,077 bronchoscopies were included in our study. The cumulative incidence of fungal infections was 14% (75 of 519). Of these patients, 10.6% (54 of 519) developed Aspergillus -related clinical syndromes. Using multivariate analysis, pre-emptive therapy was associated with significantly lower rates of invasive aspergillosis at 1 year post-transplantation compared with no pre-emptive therapy (hazard ratio [HR] 0.23, 95% confidence interval [CI] 0.09 to 0.58). Pre-emptive therapy and invasive aspergillosis had similar mortality rates compared with no invasive aspergillosis, or negative culture and galactomannan at 1 year (HR 0.54, 95% CI 0.23 to 1.28; and HR 0.99, 95% CI 0.44 to 2.25, respectively). During follow-up, 50% (259 of 519) of patients were negative for galactomannan and Aspergillus culture in bronchoalveolar lavage, and did not receive anti-fungal treatment. Only 2 patients developed invasive aspergillosis in this cohort. Conclusions Our study suggests that use of bronchoalveolar lavage culture and a galactomannan-directed pre-emptive approach significantly decreased the risk of invasive aspergillosis, allowing a 50% reduction in anti-fungal exposure compared with a universal prophylaxis approach, without affecting mortality at 1 year. [ABSTRACT FROM AUTHOR]

Invasive aspergillosis (IA) is a life- threatening infection affecting haematological cancer patients with chemotherapy- induced neutropenia. The diagnosis of IA often relies on the detection of galactomannan (GM) in serum or bronchoalveolar lavage fluid (BAL). Bi- weekly serum GM screening has been proposed for a pre- emptive therapeutic approach of IA in patients not receiving mold-active prophylaxis. We have analysed all IA cases among patients with haematological malignancies and prolonged chemotherapy-induced neutropenia (>14 days) in our institution over a 10- year period (2007- 2017). Serum GM was measured twice weekly and mold- active prophylaxis was not routinely administered. Thirty IA cases were observed and a positive serum GM was the first indicator of IA in 10 (33%) of them, which represents a need of approximately 500 GM tests for the detection of a single IA case. In the other 20 (67%) cases, suggestive chest CT lesion was the first sign of IA and bronchoscopy was required in 15 (50%) cases with negative serum GM for establishing the diagnosis of probable/proven IA. A positive serum GM was associated with a worse prognosis (57% 12-week survival vs 100% among serum GM-negative patients, P = .006), irrespective of the timing of GM positivity compared to CT. We concluded that bi- weekly serum GM screening demonstrated limited benefit in this population. [ABSTRACT FROM AUTHOR]

Objectives Exhaled breath condensate (EBC) is a noninvasive means of sampling the airways that has shown significant promise in the diagnosis of many disorders. There have been no reports of its usefulness in the detection of galactomannan (GM), a component of the cell wall of Aspergillus. The suitability of EBC for the detection of GM for the diagnosis of invasive aspergillosis (IA) using the Platelia Aspergillus enzyme-linked immunosorbent assay was investigated. Methods Prospective, cross-sectional study of lung transplant recipient and haemotologic malignancy patients at a university centre. EBC samples were compared to concomitant bronchoalveolar lavage (BAL) samples among lung transplant recipients and healthy controls. EBC was collected over 10 minutes using a refrigerated condenser according to the European Respiratory Society/American Thoracic Society recommendations, with the BAL performed immediately thereafter. Results A total of 476 EBC specimens with 444 matched BAL specimens collected from lung transplant recipients ( n = 197) or haemotologic malignancy patients ( n = 133) were examined. Both diluted and untreated EBC optical density (OD) values (0.0830, interquartile range (IQR) 0.0680–0.1040; and 0.1130, IQR 0.0940–0.1383), respectively, from all patients regardless of clinical syndrome were significantly higher than OD values in healthy control EBCs (0.0508, IQR 0.0597–0.0652; p < 0.0001). However, the OD index values did not correlate with the diagnosis of IA (44 samples were associated with IA). Furthermore, no significant correlation was found between EBC GM and the matched BAL specimen. Conclusions GM is detectable in EBC; however, no correlation between OD index values and IA was noted in lung transplant recipients. [ABSTRACT FROM AUTHOR]

Objective: This study was conducted to get a complete clinical and mycological picture of invasive aspergillosis (IA) in respiratory medicine ICU of a tertiary care hospital. Patients: From the cohort of 235 patients only one had proven IA. Based on AspICU algorithm, 21 had putative IA (8.9%), 12 were colonised (5.1%). Results: Adjusting the confounding factors, significant risk factors for IA were chronic obstructive pulmonary disease (COPD), temperature of ≥38°C, pneumonia and acute respiratory distress syndrome (ARDS). The best predictor of IA was AspICU algorithm (AUC, 1) followed by serum galactomannan antigen (GM) cut-off (≥1.24) calculated based on AspICU algorithm (AUC, 0.822). For 37% of patients, IA diagnoses was made earlier with serum GM than radiology. There were 70/235 (29.8%) deaths within 30 days of enrolment in the study. Aspergillus culture positivity (34/235, 14.5%) was associated with very high mortality (27/34, 79.4%), (p<0.05). The best predictor of mortality was GM cut-off (≥1.24) calculated based on AspICU algorithm (AUC, 0.835). Conclusion: This study imparts the focus on relatively underestimated Aspergillus infections prevalent in ICUs. The AspICU algorithm was found to be useful over others for IA diagnosis. The prognostic usefulness of serum GM antigen detection test highlighted overlooking the same may not be rewarding for the outcome of IA suspected ICU subpopulation. [ABSTRACT FROM AUTHOR]

A panel of specific monoclonal antibodies (mAbs) against synthetic pentasaccharide β--Galf-(1→5)-[β--Galf-(1→5)]3-α--Manp, structurally related to Aspergillus fumigatus galactomannan, was generated using mice immunized with synthetic pentasaccharide-BSA conjugate and by hybridoma technology. Two selected mAbs, 7B8 and 8G4, could bind with the initial pentasaccharide with affinity constants of approximately 5.3 nM and 6.4 nM, respectively, based on surface plasmon resonance-based biosensor assay. The glycoarray, built from a series of synthetic oligosaccharide derivatives representing different galactomannan fragments, demonstrated that mAb 8G4 could effectively recognize the parental pentasaccharide while mAb 7B8 recognizes its constituting trisaccharide parts. Immunofluorescence studies showed that both 7B8 and 8G4 could stain A. fumigatus cells in culture efficiently, but not the mutant strain lacking galactomannan. In addition, confocal microscopy demonstrated that Candida albicans, Bifidobacterium longum, Lactobacillus plantarum, and numerous gram-positive and gram-negative bacteria were not labeled by mAbs 7B8 and 8G4. The generated mAbs can be considered promising for the development of a new specific enzyme-linked assay for detection of A. fumigatus, which is highly demanded for medical and environmental controls. [ABSTRACT FROM AUTHOR]

To conclusively assess the value enhancing effect of enzymes targeting antinutritional non–starch polysaccharides in a specific feed source, in depth understanding of the substrate is required, to use the right enzyme for the relevant polysaccharides. In the current study a commercial non-starch polysaccharide multienzyme product obtained by submerged fermentation of Aspergillus aculeatus was supplemented to canola non-starch polysaccharides. The enzyme effects studied included substrate viscosity reduction and solubilisation of non-starch polysaccharides and crude protein as well as peptide cleavage. Results were compared with the effects obtained by a monocomponent protease and a combination of protease and the multienzyme product. Viscosity reduction of solutions of xyloglucan and galactomannan solution clearly showed the presence of xyloglucanase and galactomannan activity in the product. On enzyme supplementation, there was an increase (P < 0.05) in the solubilisation of rhamnose, fucose, arabinose, xylose, galactose and glucose non-starch polysaccharide residues. In a separate experiment using a different measuring system (HPLC) the product was also shown to solubilise galacturonic acid from canola meal. Highest concentrations of solubilised crude protein and peptides measured by combining the protease and the multienzyme product together. Antibodies (LM25, LM19 and LM 6) targeting different cell wall components were used in microscopy studies. Monoclonal antibody LM25, directed towards xyloglucan, bound abundantly to the intercellular spaces on the cytoplasmic side of the cell wall lining. On enzyme treatment with the multienzyme product the LM25 binding disappeared, indicating a reduction of xyloglucans as also was observed in a polysaccharide analysis of enzyme incubated canola meal. Monoclonal antibody LM19 recognizes de-esterified homogalacturonan epitopes in pectin also bound to the uronic acid residues in canola meal. The LM 19 signal was weak in samples treated only with buffer, but became stronger when the xyloglucan layer was removed by a purified experimental xyloglucanase. Monoclonal antibody LM6, directed towards arabinan, also became more visible in canola meal after the removal of the xyloglucan layer by the experimental xyloglucanase. Treatment with the commercial non starch polysaccharide multienzyme product resulted in degradation of arabinan and thereby also a disappearance of the LM6 signal. Both the pectin and the arabinan signal were visible mainly/only after removal of the xyloglucan layer in both the seed and the meal. [ABSTRACT FROM AUTHOR]

The study is oriented at the in vitro evaluation of the immunobiological activity and efficacy of synthetically prepared isomeric pentasaccharides representing fragments of Aspergillus fumigatus cell-wall galactomannan and containing β-(1→5)-linked tetragalactofuranoside chain attached to O-6 (GM-1) or O-3 (GM-2) of a spacer-armed mannopyranoside residue. These compounds were studied as biotinylated conjugates which both demonstrated immunomodulatory activities on the RAW 264.7 cell line murine macrophages as in vitro innate immunity cell model. Immunobiological studies revealed time- and concentration-dependent efficient immunomodulation. The proliferation of RAW 264.7 macrophages was induced at higher concentration (100 μg/mL) of studied glycoconjugates and longer exposure (48 h), with more pronounced efficacy for GM-1. The increase of proliferation followed the previous increase of IL-2 production. The cytokine profile of the macrophages treated with the glycoconjugates was predominantly pro-inflammatory Th1 type with significant increase of TNFα, IL-6, and IL-12 release for both glycoconjugates. The RAW 264.7 macrophages production of free radicals was not significantly affected by glycoconjugates stimulation. The phagocytic activity of RAW 264.7 cells was reduced following GM-1 treatment and was significantly increased after 24 h stimulation with GM-2, contrary to 48 h stimulation. Moreover, the synthetically prepared galactomannoside derivatives have been evaluated as efficient serodiagnostic antigens recognized by specific Ig isotypes, and significant presence of specific IgM antibodies in serum of patients suffering from vulvovaginitis was observed. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Objectives Galactomannan (GM) and Aspergillus DNA detection are useful tools for the diagnosis of invasive pulmonary aspergillosis (IPA), primarily in blood and bronchoscopy samples. This study aimed to evaluate the utility of both markers for detection of Aspergillus in sputum from patients with allergic bronchopulmonary aspergillosis (ABPA) and chronic pulmonary aspergillosis (CPA). Methods ABPA or CPA demographic patient data were retrieved. This retrospective observational audit included 159 patients with at least one sputum pair. 223 sputum sample pairs were analysed, as well as six control samples for GM only. Real time PCR was performed following sputum DNA extraction using the MycAssay™ Aspergillus kit and cycle thresholds were subtracted from 38 to give positive values (transformed Ct, TCt). Results The mean age of the patients was 61.81 years (SD: ± 11.06; range 29–100). One hundred and twenty-six (79.2%) had CPA. Cultures were positive for fungi in 13.1% of the samples, and A. fumigatus was the commonest (11.9%) fungus isolated. Receiver operating characteristic (ROC curve) analysis of sputum GM comparing TCt of > 0.0, and > 2.0 to derive GMI cut-off values showed a cut-off of 6.5. About 50% of sputa with strongly positive PCR values had GM values > 6.5. Two of six (33%) control samples had GM indices > 6.5. Conclusion It is not clear that GM determinations in sputum are useful for diagnosis of either CPA or ABPA, or following therapy. [ABSTRACT FROM AUTHOR]

Previously, we reported that GfsA is a novel galactofuranosyltransferase involved in the biosynthesis of O-glycan, the proper maintenance of fungal morphology, the formation of conidia and anti-fungal resistance in Aspergillus nidulans and A. fumigatus (Komachi Y et al., 2013. GfsA encodes a novel galactofuranosyltransferase involved in biosynthesis of galactofuranose antigen of O-glycan in Aspergillus nidulans and Aspergillus fumigatus. Mol. Microbiol. 90:1054-1073). In the present paper, to gain an in depth-understanding of the enzymatic functions of GfsA in A. fumigatus (AfGfsA), we established an in vitro assay to measure galactofuranosyltransferase activity using purified AfGfsA, UDP-α-D-galactofuranose as a sugar donor, and p-nitrophenyl-β-Dgalactofuranoside as an acceptor substrate. LC/MS, 1H-NMR and methylation analyses of the enzymatic products of AfGfsA revealed that this protein has the ability to transfer galactofuranose to the C-5 position of the β-galactofuranose residue via a β-linkage. AfGfsA requires a divalent cation of manganese for maximal activity and consumes UDP-α-D-galactofuranose as a sugar donor. Its optimal pH range is 6.5-7.5 and its optimal temperature range is 20-30°C. 1H-NMR, 13C-NMR and methylation analyses of fungal-type galactomannan extracted from the ΔAfgfsA strain revealed that AfGfsA is responsible for the biosynthesis of β1,5-galactofuranose in the galactofuran side chain of fungal-type galactomannan. Based on these results, we conclude that AfGfsA acts as a UDP-α-D-galactofuranose: β-D-galactofuranoside β1,5-galactofuranosyltransferase in the biosynthetic pathway of galactomannans. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Diagnosing invasive aspergillosis (IA) has long been challenging due to the inability to culture the causal Aspergillus agent from blood or other body fluids. This shortcoming has fuelled an interest in non-culture-based diagnostic techniques such as the detection of galactomannan (GM) in blood and bronchoalveolar lavage fluid, the detection of 1,3-β-d-glucan (BDG) in blood and the detection of Aspergillus DNA by PCR-based techniques. Past decades have witnessed important improvements in our understanding of the strengths and limitations of antigen assays and in the standardization of PCR-based DNA techniques. These assays are now being incorporated into care pathways and diagnostic algorithms; they help us to steward and monitor antifungal therapies and to predict treatment outcomes. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Introduction: Invasive Pulmonary Aspergillosis (IPA) is an important opportunistic infection with a high degree of mortality and morbidity. Galactomannan assay (GM assay) is found to be useful for diagnosis of IPA in patients with neutropenia. However the utility of this assay has not been evaluated in a mixed patient population with other co-morbid conditions. Though a kit cut-off of 0.5 has been recommended for the diagnosis of IPA, studies have reported a higher sensitivity with cut-offs more than 0.5. Aim: To establish an in-house cut-off and compare its utility with the kit cut-off to diagnose and categorize IPA as proven, probable and possible in patients with varied underlying risk factors. Materials and Methods: This observational study was done in St John's Medical College, Bangalore, Karnataka, India from January 2013-December 2014. GM assay was performed on 25 each of healthy controls and clinically diagnosed cases of IPA. The in-house cut-off was calculated by plotting the Receiver Operating Characteristic Curve (ROC). Results: The in-house cut-off was calculated to be 0.52. Using this and the kit cut-off (0.5), the Sensitivity, Specificity, Positive Predictive Value (PPV) and the Negative Predictive Value (NPV) were found to be 75%, 79%, 76%, 82% and 79%, 71%, 77%, 82% respectively. Diabetes mellitus was found to be associated with more than 50% of the patients. Conclusion: The established in house cut-off using healthy controls and patients with clinical diagnosis of IPA was not significantly different from that of the kit cut-off. Using either of these cut-offs, we could re-categorize two of the possible IPA cases in the probable group. This study helped to understand the clinical utility of this assay even in a mixed patient population with multiple co-morbidities. [ABSTRACT FROM AUTHOR]

Objectives: Isavuconazole, a novel triazole antifungal agent, has broad-spectrum activity against Aspergillus spp. and other pathogenic fungi. The isavuconazole exposure-response relationship in experimental invasive pulmonary aspergillosis using galactomannan index (GMI) suppression as a marker of disease clearance was explored.Methods: The impact of exposure on GMI suppression in persistently neutropenic rabbits treated with isavuconazonium sulphate (isavuconazole-equivalent dosages of 20, 40 or 60 mg/kg every 24 h, after a 90 mg/kg loading dose) for 12 days was linked using mathematical modelling. Bridging to humans using population pharmacokinetic (PK) data from a clinical trial in invasive aspergillosis was performed using Monte Carlo simulations.Results: Mean plasma isavuconazole AUC/MIC (EC50) of 79.65 (95% CI 32.2, 127.1) produced a half-maximal effect in GMI suppression. The inhibitory sigmoid Emax curve dropped sharply after an AUC/MIC of ≥30 and was near maximum (EC80) at ∼130. Bridging the experimental PK/pharmacodynamic (PD) target to human population PK data was then used to return to the rabbit model to determine a clinically relevant PD endpoint. The clinical dosing regimen used in the trial would result in a mean GMI of 4.3 ± 1.8, which is a 50% reduction from the starting GMI in the experiment.Conclusions: The clinical trial results showing the non-inferiority of isavuconazole to voriconazole for all-cause mortality further support the PK-PD endpoint, thereby demonstrating the usefulness of the rabbit model and endpoint for isavuconazole and implications on interpretive breakpoints. Importantly, the analysis supports this model as an important tool for development of antifungal agents. [ABSTRACT FROM AUTHOR]

Background: The clinical impact of the galactomannan (GM) test for the diagnosis of invasive pulmonary aspergillosis (IPA) is controversial. Our study evaluated the incidence and trends of IPA and GM testing in patients with aspergillus infections. Methods: We conducted a nationwide inpatient population study using the Taiwan National Health Insurance Research Database. A total of 346 IPA (62.14% male) patients from the years 2002 to 2011 were identified for inclusion in the study. Results: The average incidence of IPA was 1.51 per million person-years. Over the study period, we observed an increasing trend from 0.94 to 2.06 per million person-years (P < 0.0001). We observed male predominance in IPA incidence (M/F: 1.85/1.15). Both males and females showed significantly increasing trends of IPA incidence over time (0.87 to 4.55 and 0.36 to 2.07 per million person-years for the males and females, respectively). GM testing for IPA significantly increased from 2002 to 2011, and the GM test was utilized more frequently for males than females. The increase in the incidence of IPA might be positively associated with the increase in GM testing over the past decade. Conclusion: The incidence rates of both IPA and GM testing have increased over time. GM testing is recommended for the early diagnosis of patients with suspected aspergillosis. [ABSTRACT FROM AUTHOR]

Invasive pulmonary aspergillosis ( IPA) is a life-threatening infection mainly affecting immunocompromised patients. Early diagnosis is critical, but the diagnostic gold standard (histopathology and culture) is time consuming and cannot offer early confirmation of IPA. Fungal biomarkers like galactomannan ( GM) are a promising extension to the diagnostic repertoire. However, it still remains under discussion if biomarker analysis from the site of the infection is superior to testing blood samples. We retrospectively evaluated the diagnostic performance of concurrent serum GM and bronchoalveolar lavage ( BAL) GM (obtained within 24 h) of immunocompromised patients at high risk of IPA. Twenty-six proven/probable patients and eight patients with no IPA according to the EORTC/ MSG 2008 criteria were included in this study. Sensitivity, specificity, positive predictive value, negative predictive value and diagnostic odds ratio were for BAL GM: 85%, 88%, 96%, 64% and 38.5, and for serum GM: 23%, 88%, 88%, 26% and 2.1 respectively. BAL GM proved to be significantly more sensitive for the detection of IPA compared to same-day serum GM in patients at high risk of IPA ( P < 0.0001). Our data show that BAL GM testing is significantly superior to serum GM implying that diagnostic efforts should focus on specimens from the site of infection. [ABSTRACT FROM AUTHOR]

Background: Aspergillus polymerase chain reaction (PCR) was excluded from the European Organisation for the Research and Treatment of Cancer/Mycoses Study Group (EORTC/MSG) definitions of invasive fungal disease because of limited standardization and validation. The definitions are being revised. Methods: A systematic literature review was performed to identify analytical and clinical information available on inclusion of galactomannan enzyme immunoassay (GM-EIA) (2002) and β-D-glucan (2008), providing a minimal threshold when considering PCR. Categorical parameters and statistical performance were compared. Results: When incorporated, GM-EIA and β-D-glucan sensitivities and specificities for diagnosing invasive aspergillosis were 81.6% and 91.6%, and 76.9% and 89.4%, respectively. Aspergillus PCR has similar sensitivity and specificity (76.8%-88.0% and 75.0%-94.5%, respectively) and comparable utility. Methodological recommendations and commercial PCR assays assist standardization. Although all tests have limitations, currently, PCR is the only test with independent quality control. Conclusions: We propose that there is sufficient evidence that is at least equivalent to that used to include GM-EIA and β-D-glucan testing, and that PCR is now mature enough for inclusion in the EORTC/MSG definitions. [ABSTRACT FROM AUTHOR]

Background: Screening of high-risk patients for invasive aspergillosis (IA) has the potential to decrease the use of empiric antifungal agents. However, the performance of different screening methods has not been studied. Methods: We performed a meta-analysis of published studies to assess the diagnostic performance of galactomannan (GM) and polymerase chain reaction (PCR) as weekly screening tests in high-risk populations. The sensitivity and specificity of 6 approaches combining GM and PCR were estimated using the bivariate model. Results: Thirteen studies with 1670 patients met our inclusion criteria. Single positive test results had modest sensitivity and specificity for screening (respectively, 92% and 90% for GM; 84% and 76% for PCR). The screening approach with the highest sensitivity was the one that used at least 1 GM- or PCR-positive result to define a positive episode, achieving a sensitivity of 99%, significantly higher than any single test (P = .0018 compared with GM and P < .0001 compared with PCR). Meanwhile, when both GM and PCR were positive for the same patient, the specificity increased to 98%, which was not significantly different compared to the specificity of at least 2 positive GM (95%, P = .56 for the comparison) or PCR results (93%, P = .07 for the comparison). Conclusions: When screening high-risk patients for IA with GM and PCR tests, the absence of any positive test can obviate the need for antifungal agents with a negative predictive value of 100%, whereas the presence of at least 2 positive results is highly suggestive of an active infection with a positive predictive value of 88%. [ABSTRACT FROM AUTHOR]

Invasive aspergillosis (IA) is a severe infection with a 70% mortality rate. Aspergillus fumigatus is responsible for over 90% of those infections. The diagnosis of invasive aspergillosis is based on clinical sample culture and detection of fungal hyphae in histopathological examination. Additional tests may include the detection of the galactomannan antigen and of fungal genetic material in serum and bronchoalveolar washings. The present study was to assess the use of these two rapid tests in the diagnosis of invasive aspergillosis: serological one - to detect the galactomannan antigen (ELI SA assay), and real-time PCR, and to establish a possible correlation between these two methods. [ABSTRACT FROM AUTHOR]

Few studies have evaluated the performance of serum galactomannan (GM) in patients with allergic bronchopulmonary aspergillosis ( ABPA). Herein, we analyse the diagnostic performance of serum GM in ABPA. Consecutive subjects with ABPA and asthma underwent GM estimation using the Platelia assay (Bio-Rad Laboratories). An optical density index of >0.5 was considered positive. One hundred and twenty subjects (70 ABPA, 50 asthma) with a mean ( SD) age of 33.0 (13.1) were included in the study. The serum GM antigen was positive in 18 (25.7%) subjects with ABPA compared to 9 (18%) subjects with asthma without ABPA ( P = 0.32). The sensitivity of the serum GM antigen test in patients with ABPA was 25.7% [95% confidence intervals ( CI), 16-38] while the specificity was 82% (95% CI, 69-91). The positive and negative predictive values were 66.7% (95% CI, 46-84%) and 44.1% (95% CI, 34-55), respectively. The area under the ROC curve was 0.54 (95% CI, 0.44-0.64). The sensitivity increased and the specificity decreased with decreasing the serum GM cutoff, and vice versa. The results of this study suggest that serum GM estimation has a limited role in the diagnostic workup of patients with ABPA. [ABSTRACT FROM AUTHOR]

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Newer diagnostic methods may link more idiopathic pneumonia syndrome (IPS) cases to an infectious agent. Bronchoalveolar lavage (BAL) samples from 69 hematopoietic cell transplant (HCT) recipients with IPS diagnosed between 1992 and 2006 were tested for 28 pathogens (3 bacteria and 25 viruses) by quantitative polymerase chain reaction and for Aspergillus by galactomannan assay. Research BALs from 21 asymptomatic HCT patients served as controls. Among 69 HCT patients with IPS, 39 (56.5%) had a pathogen detected. The most frequent pathogens were human herpesvirus-6 (HHV-6) (N=20 [29%]) followed by human rhinovirus (HRV), cytomegalovirus (CMV) and Aspergillus (N=8 [12%] in each). HHV-6 and HRV were rarely detected in controls, whereas CMV and Aspergillus were occasionally detected with low pathogen load. Patients with pathogens had worse day-100 survival than those without (hazard ratio, 1.88; P = 0.03). Mortality in patients with only pathogens of 'uncertain' significance in lung was similar to that in patients with pathogens of 'established' significance. Metagenomic next-generation sequencing did not reveal additional significant pathogens. Our study demonstrated that approximately half of patients with IPS had pathogens detected in BAL, and pathogen detection was associated with increased mortality. Thus, an expanded infection detection panel can significantly increase the diagnostic precision for idiopathic pneumonia. [ABSTRACT FROM AUTHOR]

Background Invasive aspergillosis is an infection with high morbidity and mortality that affects mostly immunocompromised individuals. Early identification and targeted treatment of the infection is essential to improve survival of affected patients. The purpose of our review is to highlight the most recent developments in diagnosis and screening for invasive aspergillosis (IA) along with the challenges associated with the development and validation of novel diagnostic approaches. Methods Ovid MEDLINE and The Cochrane library were searched for studies that evaluated serologic, molecular and novel methodologies for the diagnosis of IA. Results Traditional diagnostic approaches, such as histopathology and culture, are still considered the gold standard but lack sufficient sensitivity. Newer serologic techniques, such as galactomannan (GM) and beta-glucan, have already been incorporated into clinical guidelines, but recent evidence suggests that their performance might be limited in certain clinical settings. Molecular methods, such as the Aspergillus spp. polymerase chain reaction ( PCR), have not yet found their place in clinical practice mainly due to lack of standardization. Novel methodologies, such as volatile organic compound detection and lateral flow devices, have recently been developed and promise noninvasive and rapid diagnosis of aspergillosis, while diagnostic algorithms that incorporate both GM and PCR have proven to be effective in early randomized trials as screening methods and can reduce the use of antifungal agents. Conclusions Diagnosis of IA remains challenging. Novel methodologies and the standardization of GM and PCR might provide more reliable diagnostic tools in the future. [ABSTRACT FROM AUTHOR]

Early diagnosis of invasive pulmonary aspergillosis ( IPA) remains difficult due to the variable performance of the tests used. We compared the performance characteristics of Aspergillus lateral flow device ( LFD) in bronchoalveolar lavage ( BAL) vs. BAL-galactomannan ( GM), for the diagnosis of IPA. 311 BAL specimens were prospectively collected from patients who underwent bronchoscopy from January to May 2013. Patients at risk for IPA were divided into haematological malignancy ( HEM) and non- HEM groups: solid organ transplants ( SOT) (lung transplant ( LT) and non- LT SOT); chronic steroid use ( CSU); solid tumour ( STU) and others. We identified 96 patients at risk for IPA; 89 patients (93%) were in the non- HEM groups: SOT 57 ( LT, 46, non- LT SOT, 11); CSU 21; STU 6, other 5. Only three patients met criteria for IA (two probable; one possible). Overall sensitivity ( SS) was 66% for both and specificity ( SP) was 94% vs. 52% for LFD and GM respectively. LFD and GM performance was similar in the HEM group ( SS 100% for both and SP 83% vs. 100% respectively). LFD performance was better than GM among non- HEM SOT patients (P = 0.02). Most false-positive GM results occurred in the SOT group (50.8%), especially among LT patients (56.5%). LFD performance was superior with an overall SP of 95.6% in SOT ( P < 0.002) and 97% in LT patients ( P = 0.0008). LFD is a rapid and simple test that can be performed on BAL to rule out IPA. [ABSTRACT FROM AUTHOR]

Invasive aspergillosis is an important cause of morbidity and mortality in immunocompromised patients. Diagnosis of this infection frequently employs detection of the circulating galactomannan in the patient serum using enzyme immunoassay (EIA), a highly sensitive and specific system. Although there are many structural studies of the galactomannan of Aspergillus fumigatus, some inconsistencies are present in these results. In this study, to clarify the relationship between the growth conditions and structure of the galactomannans, we cultured A. fumigatus using two distinct yeast/fungal cultivation media, i.e. the yeast extract–peptone–dextrose (YPD) medium and yeast nitrogen base (YNB) medium. Galactomannans prepared from the resulting culture supernatants were structurally characterized by 1H and 13C nuclear magnetic resonance, methylation analysis, acetolysis and α-mannosidase degradation. These assays revealed that the galactomannan from the YPD cultivation had short β-1,5-linked galactofuranose (Galf) oligosaccharide chains in both the O- and N-linked carbohydrate moieties, while the galactomannan from the YNB cultivation incorporated long Galf oligosaccharide chains. The galactomannans derived from the two culture conditions significantly differed in reactivity based on the EIA diagnostic system. We also demonstrated the presence of a novel Galf-containing branched oligosaccharide in the O-linked moiety. [ABSTRACT FROM PUBLISHER]

The article presents study to explore the relevance of timing of galactomannan sampling in broncho-alveolar lavage (BAL) fluid before or after antifunghal therapy. Topics discussed include review of cases in hospital for same, no difference in number of positive aspergillus cultures among groups and performance of the lavage.

The optimal combination of galactomannan index (GMI) testing for the diagnosis of invasive pulmonary aspergillosis (IPA) remains unclear. For diagnostic approaches that are triggered by clinical signs and symptoms in high-risk patients, institutional variation remains, with some centers routinely relying on only serum GMI or bronchoalveolar lavage (BAL) GMI testing. In addition, use of mold-active agents before diagnosis of IPA is becoming increasingly common, and understanding the effect of these drugs on test yield is important when making time-critical treatment decisions. In a single-center cohort of 210 allogeneic hematopoietic cell transplant recipients, we found that serum and BAL GMI testing contributed independently to IPA diagnosis, supporting the practice of sending both tests simultaneously to ensure a timely diagnosis of IPA. BAL GMI sensitivity was not affected by receipt of mold-active therapy in our cohort. [ABSTRACT FROM AUTHOR]

Highlights: [•] Exopolysaccharide AW1 was isolated from marine fungus Aspergillus ochraceus. [•] AW1 contains a mannan core of (1⟶2)-linked α-mannopyranose residues. [•] The mannopyranose residues in the backbone were substituted at C-6. [•] Side substituents are single mannopyranose and galactofuranose oligosaccharides with different DP. [•] AW1 is a galactomannan distinguishing from other exopolysaccharides. [ABSTRACT FROM AUTHOR]

This article presents information on invasive pulmonary aspergillosis (IPA), an opportunistic infection in critically ill patients. Topics discussed include the epidemiology, risk factors and outcomes of IPA, the clinical diagnosis of the disease, and the role of galactomannan in the diagnosis of IPA in neutropenic patients. Also explored are angioinvasion and tissue infarction, which represent an important hallmark in Aspergillus pathogenesis.

Aspergillus infections are major causes of morbidity and mortality among immunocompromised patients. This study was designed to investigate the galactomannan assay optical density ( OD) indices relative to the culture results in bronchoscopic samples obtained from neutropenic and non-neutropenic patients. Galactomannan OD indices from 1427 samples from 2005 to 2012, which were sent from 839 patients and were composed of bronchial lavage ( BL = 727) and bronchoalveolar lavage fluids ( BAL = 700), were retrospectively analysed. The recovery rates of Aspergillus species from these specimens were 9.4% from the combined patient group and 13.3% from the neutropenic group. Aspergillus fumigatus complex was the most frequently isolated species. The mean and median OD indices of the positive and negative culture samples are approximately 5 and 1, respectively, and 91% of all culture-positive samples have ≥1 OD index value. The receiver-operating characteristics curve analysis demonstrated that the feasibility of the Aspergillus galactomannan assay and Aspergillus galactomannan test has superior accuracy in BAL compared to BL fluids, and the test is not affected by the immune status of the patient. We suggest that the Aspergillus galactomannan test, which uses bronchoscopic material, leads to an earlier diagnosis and if the OD index is found ≥1, fungal growth can be expected. [ABSTRACT FROM AUTHOR]

Cross-reactivity of Fusarium species with serum galactomannan antigen (GMI) test has been observed. We sought to evaluate if GMI could help to early diagnose invasive fusariosis and to monitor treatment response. We reviewed the records of all patients with invasive fusariosis between 2008 and 2012 in three Brazilian hospitals. We selected patients who had at least 1 GMI test within 2 days before or after the date of the first clinical manifestation of fusariosis, and analyzed the temporal relationship between the first positive GMI test and the date of the diagnosis of invasive fusariosis, and the kinetics of GMI in relation to patients' response to treatment. We also selected 18 controls to determine the sensitivity and specificity of the test. Among 18 patients, 15 (83%) had at least one positive GMI (median 4, range 1–15). The sensitivity and specificity of was 83% and 67%, respectively. GMI was positive before the diagnosis of invasive fusariosis in 11 of the 15 cases (73%), at a median of 10 days (range 3–39), and after the diagnosis in 4 cases. GMI became negative in 8 of the 15 patients; 3 of these 8 patients (37.5%) were alive 90 days after the diagnosis of fusariosis compared with 2 of 7 (29%) who did not normalize GMI (p = 1.0). GMI is frequently positive in invasive fusariosis, and becomes positive before diagnosis in most patients. These findings may have important implications for the choice of antifungal therapy in settings with high prevalence of invasive fusariosis. [ABSTRACT FROM AUTHOR]

We examined the relationship between serum and bronchoalveolar lavage (BAL) galactomannan index (GMI) values and mortality in allogeneic hematopoietic cell transplant recipients with invasive pulmonary aspergillosis. Using a clinical sign and symptom–initiated approach, we found that the serum but not the BAL GMI level correlated with 42- and 180-day patient mortality. [ABSTRACT FROM AUTHOR]