Performance of the beta-glucan test for the diagnosis of invasive fusariosis and scedosporiosis: a meta-analysis.

The (1→3)-ß-D-glucan (BDG) is a component of the fungal cell wall that can be detected in serum and used as an adjunctive tool for the diagnosis of invasive mold infections (IMI) in patients with hematologic cancer or other immunosuppressive conditions. However, its use is limited by modest sensitivity/specificity, inability to differentiate between fungal pathogens, and lack of detection of mucormycosis. Data about BDG performance for other relevant IMI, such as invasive fusariosis (IF) and invasive scedosporiosis/lomentosporiosis (IS) are scarce. The objective of this study was to assess the sensitivity of BDG for the diagnosis of IF and IS through systematic literature review and meta-analysis. Immunosuppressed patients diagnosed with proven or probable IF and IS, with interpretable BDG data were eligible. A total of 73 IF and 27 IS cases were included. The sensitivity of BDG for IF and IS diagnosis was 76.7% and 81.5%, respectively. In comparison, the sensitivity of serum galactomannan for IF was 27%. Importantly, BDG positivity preceded the diagnosis by conventional methods (culture or histopathology) in 73% and 94% of IF and IS cases, respectively. Specificity was not assessed because of lacking data. In conclusion, BDG testing may be useful in patients with suspected IF or IS. Combining BDG and galactomannan testing may also help differentiating between the different types of IMI.

IF and IS are severe fungal infections for which diagnosis is often delayed. This meta-analysis shows that beta-glucan testing in serum had a sensitivity of about 80% for IF/IS and could detect the disease earlier compared to conventional diagnostic tests.

Use of 1,3-Beta-D-Glucan concentration in peritoneal fluid for the diagnosis of intra-abdominal Candidiasis in Critically-ill patients.

Intra-Abdominal Candidiasis (IAC) is frequent and associated with high mortality in intensive care unit (ICU) patients. Antifungal treatments may be overused due to a lack of diagnostic tools to rule out IAC. Serum 1,3-Beta-D-Glucan (BDG) concentrations are used to diagnose Candida infections, its concentration in peritoneal fluid (PF) may help to confirm or invalidate the diagnosis of IAC. We performed a non-interventional, prospective, multicenter study, at the Hospices Civils de Lyon, France, in seven ICU located in three different hospitals from December 2017 to June 2018. IAC was defined as the isolation of Candida in a sample collected from the intra-abdominal cavity under sterile conditions in patients displaying clinical evidence of intra-abdominal infection. Among the 113 included patients, 135 PF samples corresponding to 135 intra-abdominal infection episodes were collected and BDG concentrations were assessed. IAC accounted for 28 (20.7%) of the intra-abdominal infections. Antifungals were administered empirically to 70 (61.9%) patients; among them, 23 (32.9%) had an IAC. The median [IQR] BDG value was significantly higher in IAC (8100 [3000;15000] pg/mL) than in non-IAC samples (1961 [332;10650] pg/mL). BDG concentrations were higher in PF with Fecaloid aspect and in case of positive bacterial culture. For a BDG threshold of 125 pg/mL, the negative predictive value to assess IAC was 100%. In conclusion, low BDG PF concentrations could be used to rule out IAC. https://clinicaltrials.gov/ct2/show/NCT03469401.

Intra-Abdominal Candidiasis (IAC) is associated with a high mortality in Intensive Care Unit (ICU) patients. 1,3-Beta-D-Glucan (BDG), a component of Candida cell wall, was prospectively measured in peritoneal fluid from ICU patients Low peritoneal BDG concentrations may be used to rule out IAC.

Combination of serum and peritoneal 1.3-beta-D-glucan can rule out intra-abdominal candidiasis in surgical critically ill patients: a multicenter prospective study.

BACKGROUND: Intra-abdominal candidiasis (IAC) is difficult to predict in critically ill patients with intra-abdominal infection, leading to the overuse of antifungal treatments. Serum and peritoneal 1.3-beta-D-glucan (sBDG and pBDG) have been proposed to confirm or invalidate the diagnosis of IAC, but clinical studies have reported inconsistent results, notably because of heterogeneous populations with a low IAC prevalence. This study aimed to identify a high-risk IAC population and evaluate pBDG and sBDG in diagnosing IAC. METHODS: This prospective multicenter noninterventional French study included consecutive critically ill patients undergoing abdominal surgery for abdominal sepsis. The primary objective was to establish the IAC prevalence. The secondary objective was to explore whether sBDG and pBDG could be used to diagnose IAC. Wako® beta-glucan test (WT, Fujifilm Wako Chemicals Europe, Neuss, Germany) was used for pBDG measurements. WT and Fungitell® beta-D-glucan assay (FA, Associate of Cape Cod, East Falmouth, USA) were used for sBDG measurements. RESULTS: Between 1 January 2020 and 31 December 2022, 199 patients were included. Patients were predominantly male (63%), with a median age of 66 [54-72] years. The IAC prevalence was 44% (87/199). The main IAC type was secondary peritonitis. Septic shock occurred in 63% of cases. After multivariate analysis, a nosocomial origin was associated with more IAC cases (P = 0.0399). The median pBDG level was significantly elevated in IAC (448 [107.5-1578.0] pg/ml) compared to non-IAC patients (133 [16.0-831.0] pg/ml), P = 0.0021. For a pBDG threshold of 45 pg/ml, the negative predictive value in assessing IAC was 82.3%. The median sBDG level with WT (n = 42) at day 1 was higher in IAC (5 [3.0-9.0] pg/ml) than in non-IAC patients (3 [3.0-3.0] pg/ml), P = 0.012. Similarly, median sBDG level with FA (n = 140) at day 1 was higher in IAC (104 [38.0-211.0] pg/ml) than in non-IAC patients (50 [23.0-141.0] pg/ml), P = 0.009. Combining a peritonitis score < 3, sBDG < 3.3 pg/ml (WT) and pBDG < 45 pg/ml (WT) yielded a negative predictive value of 100%. CONCLUSION: In critically ill patients with intra-abdominal infection requiring surgery, the IAC prevalence was 44%. Combining low sBDG and pBDG with a low peritonitis score effectively excluded IAC and could limit unnecessary antifungal agent exposure. TRIAL REGISTRATION: The study was registered with ClinicalTrials.gov (ID number 03997929, first registered on June 24, 2019).

Prospective Evaluation of the Fungitell® (1→3) Beta-D-Glucan Assay as a Diagnostic Tool for Invasive Fungal Disease in Pediatric Allogeneic Hematopoietic Cell Transplantation: A Report from the Children's Oncology Group.

BACKGROUND: Invasive fungal disease (IFD) is a major source of morbidity and mortality for hematopoietic cell transplant (HCT) recipients. Non-invasive biomarkers, such as the beta-D-glucan assay, may improve the diagnosis of IFD. The objective was to define the utility of surveillance testing using Fungitell® beta-D-glucan (BDG) assay in children receiving antifungal prophylaxis in the immediate post-HCT period. METHODS: Weekly surveillance blood testing with the Fungitell® BDG assay was performed during the early post-HCT period in the context of a randomized trial of children, adolescents, and young adults undergoing allogeneic HCT allocated to triazole or caspofungin prophylaxis. Positivity was defined at the manufacturer cutoff of 80 pg/ml. IFD was adjudicated using blinded central reviewers. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for the Fungitell® BDG assay for the outcome of proven or probable IFD. RESULTS: A total of 51 patients (out of 290 patients in the parent trial) contributed blood specimens. In total, 278 specimens were evaluated. Specificity was 80.8% (95% confidence interval [CI]: 75.6%-85.3%), and NPV was over 99% (95% CI: 86.8%-99.9%). However, there were no true positive results, resulting in sensitivity of 0% (95% CI: 0.0%-84.2%) and PPV of 0% (95% CI: 0.0%-6.7%). CONCLUSIONS: Fungitell® BDG screening is of limited utility in diagnosing IFD in the post-HCT period, mainly due to high false-positive rates. Fungitell® BDG surveillance testing should not be performed in children during the early post-HCT period while receiving antifungal prophylaxis as the pretest probability for IFD is low.

Negative serum (1,3) -ß-D-glucan has a low power to exclude Pneumocystis jirovecii pneumonia (PJP) in HIV-uninfected patients with positive qPCR.

OBJECTIVE: The current study evaluated the diagnostic performance of serum (1,3)-beta-D Glucan (BDG) in differentiating PJP from P. jirovecii-colonization in HIV-uninfected patients with P. jirovecii PCR-positive results. METHODS: This was a single-center retrospective study between 2019 and 2021. The diagnosis of PJP was based on the following criteria: detection of P. jirovecii in sputum or BAL specimen by qPCR or microscopy; Meet at least two of the three criteria: (1) have respiratory symptoms of cough and/or dyspnea, hypoxia; (2) typical radiological picture findings; (3) receiving a complete PJP treatment. After exclusion, the participants were divided into derivation and validation cohorts. The derivation cohort defined the cut-off value of serum BDG. Then, it was verified using the validation cohort. RESULTS: Two hundred and thirteen HIV-uninfected patients were enrolled, with 159 PJP and 54 P. jirovecii-colonized patients. BDG had outstanding specificity, LR, and PPV for PJP in both the derivation (90.00%, 8.900, and 96.43%) and the validation (91.67%, 9.176, and 96.30%) cohorts at ≥ 117.7 pg/mL. However, it had lower sensitivity and NPV in the derivation cohort (89.01% and 72.97%), which was even lower in the validation cohort (76.47% and 57.89%). Of note, BDG ≥ 117.7 pg/mL has insufficient diagnostic efficacy for PJP in patients with lung cancer, interstitial lung disease (ILD) and nephrotic syndrome. And although lymphocytes, B cells, and CD4+ T cells in PJP patients were significantly lower than those in P. jirovecii-colonized patients, the number and proportion of peripheral blood lymphocytes did not affect the diagnostic efficacy of serum BDG. CONCLUSIONS: Serum BDG ≥ 117.7 pg/mL could effectively distinguish P. jirovecii-colonization from infection in qPCR-positive HIV-uninfected patients with infectious diseases, solid tumors (excluding lung cancer), autoimmune or inflammatory disorders, and hematological malignancies. Of note, for patients with lung cancer, ILD, and nephrotic diseases, PJP should be cautiously excluded at BDG < 117.7 pg/mL.

The influence of continuous renal replacement therapy on 1,3-ß-d-glucan levels in critically ill patients: a single-center retrospective propensity score study.

1,3-ß-d-Glucan (BDG) is commonly used for diagnosing invasive fungal infections (IFIs). While exposure to cellulose-based hemodialyzers is known to cause false-positive BDG results, the impact of modern hemofilters used in continuous renal replacement therapy (CRRT) remains unclear. This retrospective, single-center cohort study aimed to evaluate the effect of CRRT on BDG levels in critically ill patients. We included adult intensive care unit (ICU) patients with ≥1 BDG measurement between December 2019 and December 2020. The primary outcome was the rate of false-positive BDG results in patients exposed to CRRT compared to unexposed patients. Propensity score analysis was performed to control for confounding factors. A total of 103 ICU patients with ≥1 BDG level were identified. Most (72.8%) were medical ICU patients. Forty patients underwent CRRT using hemofilter membranes composed of sodium methallyl sulfonate copolymer (AN 69 HF) (82.5%) and of polyarylethersulfone (PAES) (17.5%). Among the 91 patients without proven IFI, 31 (34.1%) had false-positive BDG results. Univariable analysis showed an association between CRRT exposure and false-positive BDG results. However, the association between CRRT exposure and false-positive BDG results was no longer significant across three propensity score models employed: 1:1 match (n = 32) (odds ratio (OR) 1.65, p = .48), model-adjusted (n = 91) (OR 1.75, p = .38), quintile-adjusted (n = 91) (OR 1.78, p = .36). In this single-center retrospective analysis, exposure to synthetic CRRT membranes did not independently increase the risk of false-positive BDG results. Larger prospective studies are needed to further evaluate the association between CRRT exposure and false-positive BDG results in critically ill patients with suspected IFI.

Highly Conserved gsc1 Gene of Pneumocystis jirovecii in Patients with or without Prior Exposure to Echinocandins.

Echinocandins are noncompetitive inhibitors of the GSC1 subunit of the enzymatic complex involved in synthesis of 1,3-beta-d-glucan, a cell wall component of most fungi, including Pneumocystis spp. Echinocandins are widely used for treating systemic candidiasis and rarely used for treating Pneumocystis pneumonia. Consequently, data on P. jirovecii gsc1 gene diversity are still scarce compared to that for the homologous fks1 gene of Candida spp. In this study, we analyzed P. jirovecii gsc1 gene diversity and the putative selection pressure of echinocandins on P. jirovecii. gsc1 gene sequences of P. jirovecii specimens from two patient groups were compared. One group of 27 patients had prior exposure to echinocandins, whereas the second group of 24 patients did not, at the time of P. jirovecii infection diagnoses. Two portions of the P. jirovecii gsc1 gene, HS1 and HS2, homologous to hot spots described in Candida spp., were sequenced. Three single-nucleotide polymorphisms (SNPs) at positions 2204, 2243, and 2303 close to the HS1 region and another SNP at position 4540 more distant from the HS2 region were identified. These SNPs represent synonymous mutations. Three gsc1 HS1 alleles, A, B, and C, and two gsc1 HS2 alleles, a and b, and four haplotypes, Ca, Cb, Aa, and Ba, were defined, without significant difference in haplotype distribution in both patient groups (P = 0.57). Considering the identical diversity of P. jirovecii gsc1 gene and the detection of synonymous mutations in both patient groups, no selection pressure of echinocandins among P. jirovecii microorganisms can be pointed out so far.

Can Beta-D-Glucan testing as part of the diagnostic pathway for invasive fungal infection reduce anti-fungal treatment costs?

We performed a cost comparison of the current diagnostic and treatment pathway for invasive fungal infection (IFI) versus a proposed pathway that incorporates Beta-D-Glucan (BDG) testing from the NHS perspective. A fungal pathogen was identified in 58/107 (54.2%) patients treated with systemic anti-fungals in the Critical Care Department. Mean therapy duration was 23 days (standard deviation [SD] = 22 days), and cost was £5590 (SD = £7410) per patient. Implementation of BDG tests in the diagnostic and treatment pathway of patients with suspected IFI could result in a mean saving of £1643 per patient should a result be returned within 2 days. LAY SUMMARY: Invasive fungal infection increases the risk of death in very sick people. So, treatment is started before test results are known. Beta-D-Glucan (BDG) test is faster than standard blood culture tests. We estimate that using BDG tests in how patients are diagnosed could save about £1643 per patient.

Serial (1-3)-beta-D-Glucan (BDG) monitoring shows high variability among premature neonates.

This study aimed to characterize the baseline values and dynamics of serum (1,3)-Beta-D-Glucan (BDG) in neonates at high risk of neonatal invasive candidiasis (NIC); as well as to determine the effect of various clinical variables on these levels. Single center prospective cohort study was performed including 20 high-risk neonates (gestational age < 29 weeks and/or birth weight ≤ 1000 gr). Samples for BDG (Fungitell® assay) were obtained twice weekly during 6 weeks. Nineteen neonates were enrolled with a median gestational age of 25 weeks (IQR 24-27), median birth weight of 730 gr (IQR 650-810). None of the neonates was diagnosed with NIC. 190 serum samples were included. The median BDG value was 59 pg/ml (IQR 30-148), mean was 119 pg/ml (SD ± 154). A total of 42.1% (80/190) samples showed values ≥80 pg/ml, with all the neonates presenting at least one test above this cut-off. Neonatal age did not show an association with BDG levels. Exposure to steroids and the use of a heel prick as sampling method were associated with statistically significant higher BDG levels. The BDG levels showed high variability and in a significant proportion of samples values were above the threshold for positivity (e.g., ≥80 pg/ml) in the absence of NIC. The exposure to postnatal steroids and the heel prick as the method of blood sampling were associated with higher BDG levels. LAY SUMMARY: Neonatal invasive candidiasis (NIC) presents high morbi-mortality. The diagnosis of NIC is often challenging. Blood cultures have limitations and better diagnostic tools are needed. Beta-D-glucan is a diagnostic marker which could be potentially used, although still more clinical data are required.

Introducing 1,3-beta-d-glucan for screening and diagnosis of invasive fungal diseases in Australian high-risk haematology patients: is there a clinical benefit?

BACKGROUND: Early, accurate diagnosis of invasive fungal disease (IFD) improves clinical outcomes. 1,3-beta-d-glucan (BDG) (Fungitell, Associates of Cape Cod, Inc., Falmouth, MA, USA) detection can improve IFD diagnosis but has been unavailable in Australia. AIMS: To assess performance of serum BDG for IFD diagnosis in a high-risk Australian haematology population. METHODS: We compared the diagnostic value of weekly screening of serum BDG with screening by Aspergillus polymerase chain reaction and Aspergillus galactomannan in 57 at-risk episodes for the diagnosis of IFD (proven, probable, possible IFD). RESULTS: IFD episodes were: proven (n = 4); probable (n = 4); possible (n = 18); and no IFD (n = 31). Using two consecutive BDG results of ≥80 pg/mL to call a result 'positive', the sensitivity, specificity, positive predictive value and negative predictive value was 37.5%, 64.5%, 23.1% and 80.7% respectively. For invasive aspergillosis, test performance increased to 50%, 90.3%, 57.1% and 87.5% respectively if any two of serum BDG/Aspergillus polymerase chain reaction/galactomannan yielded a 'positive' result. In proven/probable IFD, five of eight episodes returned a positive BDG result earlier (mean 6.6 days) than other diagnostic tests. False-negative BDG results occurred in three of eight episodes of proven/probable IFD, and false positive in 10 of 31 patients with no IFD. Erratic patterns of BDG values predicted false positive results (P = 0.03). Using serum BDG results, possible IFD were reassigned to either 'no' or 'probable' IFD in 44% cases. Empiric anti-fungal therapy use may have been optimised by BDG monitoring in 38.5% of courses. CONCLUSIONS: The BDG assay can add diagnostic speed and value but was hampered by low sensitivity and positive predictive value in Australian haematology patients.

Lower beta-1,3-D-glucan testing cut-offs increase sensitivity for non-albicans Candida species bloodstream infections.

PURPOSE: Fungal biomarkers support early diagnosis of invasive fungal infections. In this study, we evaluated the impact of a recent update to the manufacturer-recommended cut-off for beta-1,3-D-glucan (BDG) testing (Fujifilm Wako BDG assay) on sensitivity and specificity for the detection of candidemia. Additionally, we compared the performance with tests for Candida antigen (Ag by Serion ELISA antigen Candida, Virion\Serion) and anti-mannan antibodies (Ab by Hemkit Candida IHA, Ravo Diagnostika). METHODS: Sera of 82 patients with candidemia, which were sampled with a maximum distance of ±14 days from the date of sampling of the corresponding positive blood cultures, were retrospectively analysed for BDG, Ag and Ab. Results of BDG testing were compared with results from sera of 129 patients with candidemia from a different hospital. RESULTS: Sensitivity of BDG testing (47%) was higher than for Ag (17%) or Ab (20%). By combining Ag and Ab testing, sensitivity was raised to 32%. Lowering the cut-off of BDG from 11 pg/ml to the newly recommended cut-off of 7 pg/ml resulted in a significant increase in sensitivity (47% vs 58%, p = .01 and 63% vs 71% p < .01). At both centres, the increase was significant in NAC but not in C. albicans candidemia. No significant effects on specificity were observed. CONCLUSION: BDG testing outperformed Ag and Ab testing and its combination. Lowering the BDG cut-off had no significant impact on specificity. The increase in sensitivity can be mainly attributed to a gain in sensitivity for non-albicans Candida species bloodstream infections.

Clinical features, diagnosis and treatment outcome of fungal endocarditis: A systematic review of reported cases.

The landscape of fungal endocarditis (FE) has constantly been evolving in the last few decades. Despite the advancement in diagnostic methods and the introduction of newer antifungals, mortality remains high in FE. This systematic review aimed to evaluate the epidemiology, clinical features, diagnostic and therapeutic interventions in patients with FE. We also aim to examine the aforementioned factors as a determinant of mortality in FE. A literature search was performed in PubMed, Google Scholar and Scopus, and all patients ≥18 years with proven fungal endocarditis were included. A total of 220 articles (250 patients) were included in the final analysis. Candida was the commonest aetiology (49.6%), followed by Aspergillus (30%) and Scedosporium species (3.2%). The proportion of prosthetic valve endocarditis (PVE) and intravenous drug users was 35.2% and 16%, respectively. The overall mortality rate was 40%. On multivariate analysis, Aspergillus endocarditis (HR 3.7, 95% CI 1.4-9.7; p = .009) and immunocompromised state (HR 2.8, 95% CI 1.24-6.3; p = .013) were independently associated with mortality. Patients treated with surgery along antifungals had better survival (HR 0.20, 95% CI 0.09-0.42; p < .001) compared to those treated with antifungals alone. Recurrence of FE was reported in 10.4% of patients. In conclusion, FE carries significant mortality, particularly in immunodeficient and Aspergillus endocarditis. We advocate the use of surgery combined with antifungals to improve clinical outcomes.

Candida Pneumonia: An Innocent Bystander or a Silent Killer?

Invasive candidiasis is predominantly seen in immunosuppressed patients and carries a significant mortality. The clinical spectrum of invasive candidiasis encompasses candidemia and disseminated infection (intra-abdominal abscess, osteomyelitis, endophthalmitis, and Candida meningitis). The existence of Candida pneumonia has been largely debated over the years due to its rarity and presence of frequent colonization. Demonstration of Candida species by lung biopsy along with evidence of inflammation is the only way to confirm this entity. The interpretation of Candida in respiratory specimens and the decision to initiate antifungal therapy is controversial due to the lack of clinical evidence. In this mini-review, we discuss the currently available clinical data from the literature on Candida pneumonia and future perspectives regarding the need for antifungal therapy in such patients.

Prospective Evaluation of the Turbidimetric ß-D-Glucan Assay and 2 Lateral Flow Assays on Serum in Invasive Aspergillosis.

BACKGROUND: Invasive aspergillosis (IA) remains a potentially lethal disease and requires timely diagnosis and initiation of antifungal therapy. Recently, the IMMY lateral flow assay (LFA), the OLM Diagnostics lateral flow device (LFD), and the Wako turbidimetric ß-d-glucan assay have been approved for use as a diagnostic aid. However, their performance in diagnosing IA on serum samples from at-risk patients and the added value to the existing detection of serum galactomannan remain to be investigated. METHODS: We prospectively collected serum samples from 239 hematology patients and evaluated the diagnostic performance of these 3 assays while using the 2019 EORTC/MSG definitions (study number S59863/S61797, NCT03004092). RESULTS: We identified 5 cases of proven IA, 36 cases of probable IA, and 188 controls. The LFA had the highest negative predictive value (NPV) and sensitivity (0.90 and 0.49, respectively) while galactomannan detection had the highest positive predictive value and specificity (0.93 and 0.99, respectively). Sensitivity was not significantly different between both tests. When used in combination, the highest NPV was seen in patients with a negative LFA and a negative ß-d-glucan test. The sensitivity of the LFD was significantly lower than the LFA. After omitting serum galactomannan from the definitions to control for incorporation bias, the sensitivity of the LFA outperformed galactomannan detection (0.41 vs 0.31, P = .046). CONCLUSIONS: The LFA is a fast and effective alternative to serum galactomannan detection for the diagnosis of IA and is especially useful for centers with low sample throughputs. The addition of the Wako ß-D-glucan assay further improves the diagnostic performance.

Challenges with Utilizing the 1,3-Beta-d-Glucan and Galactomannan Assays To Diagnose Invasive Mold Infections in Immunocompromised Children.

Establishing the diagnosis of invasive mold infections (IMI) in immunocompromised children is challenging due to nonspecific clinical presentations and the limited sensitivity of traditional culture-based methods. Rapid non-culture-based diagnostics such as the 1,3-beta-d-glucan and galactomannan assays have emerged as promising adjuncts to conventional diagnostic tests in adults. Available data suggest that 1,3-beta-d-glucan has limited accuracy in the pediatric population and is not recommended to be used for the diagnosis of IMI in children. On the other hand, the diagnostic performance of the serum and bronchoalveolar lavage galactomannan in immunocompromised children is comparable to results observed in adults and can be used as a screening tool in children at high risk of developing invasive aspergillosis (IA) who are not receiving mold-active antifungal prophylaxis and as a diagnostic tool in symptomatic children suspected of having IA. Herein, we summarize the available evidence for the use of these rapid non-culture-based diagnostics in immunocompromised children. We also summarize potential causes of false positivity for the 1,3-beta-d-glucan and galactomannan assays.

Immunomodulation Through Beta-D-glucan in Chemically-induced Necrotizing Pancreatitis.

BACKGROUND: Although the ability of ß-D-glucan and monophosphoryl lipid A (MPLA) to modulate immune responses has been studied in human primary cells, their effect on sterile inflammation models such as necrotizing pancreatitis has never been investigated. MATERIALS AND METHODS: 85 male New Zealand rabbits were assigned into following groups: A: control, B: pretreatment with ß-D-glucan 3 d before pancreatitis, C: pretreatment with MPLA 3 d before pancreatitis, D: pretreatment with ß-D-glucan and laminarin 3 d before pancreatitis, E: treatment with ß-D-glucan 1 d after pancreatitis, and F: MPLA 1 d after pancreatitis. Pancreatitis was induced by sodium taurocholate injection into the pancreatic duct and parenchyma. Survival was recorded for 21 d. On days 1, 3, and 7, blood was collected for amylase measurement. Peripheral blood mononuclear cells were isolated and stimulated for tumor necrosis factor alpha and interleukin 10 production. Pancreatic necrosis and tissue bacterial load were assessed. RESULTS: 21-d survival was prolonged after pretreatment or treatment with ß-D-glucan; this benefit was lost with laminarin administration. At sacrifice, pancreatic inflammatory alterations were more prominent in the control group. Bacterial load was lower after pretreatment or treatment with ß-D-glucan and MPLA. Tumor necrosis factor alpha production from stimulated peripheral blood mononuclear cells was significantly decreased, whereas interleukin 10 production remained unaltered after pretreatment or treatment with ß-D- glucan. CONCLUSIONS: ß-D-glucan reduces mortality of experimental pancreatitis in vivo. This is mediated through attenuation of cytokine production and prevention of bacterial translocation.

Low cut-off value of serum (1,3)-beta-D-glucan for the diagnosis of Pneumocystis pneumonia in non-HIV patients: a retrospective cohort study.

BACKGROUND: Non-human immunodeficiency virus (HIV) Pneumocystis pneumonia (PCP) is a fulminant disease with an increasing incidence. The serum beta-D-glucan (BDG) assay is used as an adjunct to the diagnosis of PCP; however, the cut-off value for this assay is not well-defined, especially in the non-HIV PCP population. Therefore, we aimed to identify the assay cut-off value for this population. METHODS: In this retrospective observational study, we reviewed the medical records of all patients (≥ 18 years old) with clinical suspicion of PCP who underwent evaluation of respiratory tract specimens between December 2008 and June 2014 at Kameda Medical Center. We created a receiver operating characteristic curve and calculated the area under the curve to determine the cut-off value for evaluating the inspection accuracy of the BDG assay. RESULTS: A total of 173 patients were included in the study. Fifty patients showed positive results in specimen staining, loop-mediated isothermal amplification assay, and polymerase chain reaction test, while 123 patients showed negative results. The receiver operating characteristic analyses suggested that the BDG cut-off level was 8.5 pg/mL, with a sensitivity and specificity of 76% and 76%, respectively. CONCLUSIONS: The Wako-BDG cut-off value for the diagnosis of non-HIV PCP is 8.5 pg/mL, which is lower than the classical cut-off value from previous studies. Clinicians should potentially consider this lower BDG cut-off value in the diagnosis and management of patients with non-HIV PCP. TRIAL REGISTRATION:  The participants were retrospectively registered.

Glucan rich nutrition does not increase gut translocation of beta-glucan.

BACKGROUND: (1-3)-b-D-glucan (BDG) is a fungal cell wall component and, in the absence of invasive fungal infection, a novel biomarker for microbial translocation of endogenous fungal products from the gastrointestinal tract into systemic circulation. However, its value as a marker of fungal translocation is limited by a concern that plant BDG-rich food influences blood BDG levels. METHODS: We conducted a pilot clinical trial to evaluate the impact of a standardised oral BDG challenge on blood BDG levels in participants with and without elevated microbial translocation. We enrolled 14 participants including 8 with HIV infection, 2 with advanced liver cirrhosis, and 4 healthy controls. After obtaining a baseline blood sample, participants received a standardised milkshake containing high levels of BDG followed by serial blood samples up to 8 hours after intake. RESULTS: The standardised oral BDG challenge approach did not change the blood BDG levels over time in all participants. We found consistently elevated blood BDG levels in one participant with advanced liver cirrhosis and a single person with HIV with a low CD4 count of 201 cells/mm3 . CONCLUSION: Our findings indicate that BDG blood levels were not influenced by plant origin BDG-rich nutrition in PWH, people with advanced liver cirrhosis, or healthy controls. Future studies are needed to analyse gut mycobiota populations in individuals with elevated blood BDG levels.

Diagnostic value of serum human Galactomannan aspergillus antigen and 1,3-beta-D-glucan in immunocompromised patient suspected fungal infection.

BACKGROUND: The prevalence of fungal infection (FI) in developing countries is high, but the diagnosis of FI is still challenging to determine, so it is needed evaluation of biomarkers other than microbiological culture, because the culture has low sensitivity, high cost, not available in every laboratory and needs a long time. The detection of human galactomannan Aspergillus antigen (GAL) and 1,3-beta-D-glucan (BDG) on the fungal cell wall could be the promising biomarkers for fungal infection. Neutropenia, lymphopenia and CD4T cells in the immunocompromised patients are essential factors, but these cell associations with BDG and GAL levels have not been evaluated yet. The study aimed to evaluate GAL and BDG for detecting fungal infection and their association with total leucocyte count, neutrophil, monocyte, lymphocyte and CD4T cells. METHOD: A cross-sectional study was conducted among 86 patient with suspected FI. Fungal infection established using EORTC/MSG criteria. Serology test performed using ELISA. Leucocyte cells were measured using a haematology autoanalyser, and CD4T cells were analysed using BD FACSPresto. Statistical analysis obtained using Spearman's correlation coefficient, ROC curve analysis and 2 × 2 contingency table. RESULTS: Serum Galactomannan and BDG had a significant correlation with CD4T cells and total lymphocyte count (p < 0.05). The cut-off OD GAL >0.3 had sensitivity 54.6%, specificity 87.5% and AUC 0.71; meanwhile, the BDG cut-off >115.78 pg/ mL had sensitivity 71.2%, specificity 52.4% and AUC 0.63 for detecting fungal infection. CONCLUSIONS: The immunocompromised patients can undergo GAL for determining the diagnose of FI. The lower the CD4T cells and total lymphocyte count, the higher the GAL and BDG serum levels.

Possibility of Japanese Cedar Pollen Causing False Positives in the Deep Mycosis Test.

Because Japanese cedar pollen (JCP) contains beta-1,3-d-glucan (BG), there is concern that its lingering presence in the atmosphere, especially during its scattering period, may cause false positives in the factor-G-based Limulus amebocyte lysate (LAL) assay used to test for deep mycosis (i.e., G-test). Hence, we examined whether the LAL assay would react positively with substances contained in JCP by using the G-test to measure JCP particles and extracts. BG was purified from the JCP extract on a BG-specific affinity column, and the percentage extractability was measured using three different BG-specific quantitative methods. The G-test detected 0.4 pg BG in a single JCP particle and 10 fg from a single particle in the extract. The percentage extractability of JCP-derived BG was not significantly different among the three quantitative methods. As the JCP particles should technically have been removed during serum separation, they should be less likely to be a direct false-positive factor. However, given that the LAL-assay-positive substances in the JCP extract were not distinguishable by the three BG-specific quantitative methods, we conclude that they may cause the background to rise. Therefore, in Japan false positives arising from JCP contamination should be considered when testing patients for deep mycosis.