Combination of Systemic and Lock-Therapies with Micafungin Eradicate Catheter-Based Biofilms and Infections Caused by Candida albicans and Candida parapsilosis in Neutropenic Rabbit Models

Vascular catheter-related infections, primarily caused by Candida albicans and Candida parapsilosis, pose significant challenges due to the formation of biofilms on catheters, leading to refractory disease and considerable morbidity. We studied the efficacy of micafungin in systemic and lock therapies to eliminate catheter-based biofilms and deep tissue infections in experimental central venous catheter (CVC)-related candidemia in neutropenic rabbits. Silastic CVCs in rabbits were inoculated with 1 × 103 CFU/mL of C. albicans or C. parapsilosis, establishing catheter-based biofilm, and subjected to various treatments. Neutropenic rabbits treated with a combination of lock therapy and systemic micafungin demonstrated the most significant reduction in fungal burden, from 5.0 × 104 to 1.8 × 102 CFU/mL of C. albicans and from 5.9 × 104 to 2.7 × 102 CFU/mL of C. parapsilosis (p ≤ 0.001), in the CVC after 24 h, with full clearance of blood cultures after 72 h from treatment initiation. The combination of lock and systemic micafungin therapy achieved eradication of C. albicans from all studied tissues (0.0 ± 0.0 log CFU/g) vs. untreated controls (liver 7.5 ± 0.22, spleen 8.3 ± 0.25, kidney 8.6 ± 0.07, cerebrum 6.3 ± 0.31, vena cava 6.6 ± 0.29, and CVC wash 2.3 ± 0.68 log CFU/g) (p ≤ 0.001). Rabbits treated with a combination of lock and systemic micafungin therapy demonstrated a ≥2 log reduction in C. parapsilosis in all treated tissues (p ≤ 0.05) except kidney. Serum (1→3)-β-D-glucan levels demonstrated significant decreases in response to treatment. The study demonstrates that combining systemic and lock therapies with micafungin effectively eradicates catheter-based biofilms and infections caused by C. albicans or C. parapsilosis, particularly in persistently neutropenic conditions, offering promising implications for managing vascular catheter-related candidemia and providing clinical benefits in cases where catheter removal is not feasible.

Effects of Different Container Types on (1→3)-β-D-glucan Recovery

It has long been known that containers for sample analysis or storage can play a role in endotoxin recovery and have to be taken into account when determining endotoxin concentrations. However, there is little data on the effects of containers regarding (1→3)-β-D-glucan, which plays a role as a contaminant in endotoxin measurements. To determine the effect of the container on (1→3)-β-D-glucan measurements, four different types of containers were investigated at different temperatures and stored for up to 28 days. For short-term storage for 3 h at room temperature, no effect of the container on the (1→3)-β-D-glucan recovery could be observed, but for storage at -20 °C, the results indicate that the storage time and temperature influences (1→3)-β-D-glucan detection. All containers showed a trend of lower recoveries over time, but the polyethylene container showed a significantly lower recovery compared to the other containers. We also showed that freeze/thaw cycles had a strong influence on the recovery of (1→3)-β-D-glucan in polyethylene containers. Our study showed that the container can affect not only the detection of endotoxins but also the detection of (1→3)-β-D-glucans.

Comparative Study of Three Commercial Blood (1→3)-β-D-glucan Detection Reagents for Invasive Mycosis

BACKGROUND

β-D-glucan detection is a useful diagnostic indicator of invasive mycosis. However, the differences among the commercial β-D-glucan assays are unclear. Herein, we explored the diagnostic value of various β-D-glucan assay reagents.

METHODS

This prospective observational study involved 175 eligible patients suspected to have fungal infections. For all participants, culture examinations were conducted with specimens obtained from the infected site (or blood culture), and β-D-glucan was measured using three commercial kits: Wako β-glucan test (Wako), Fungitech G-test MKII "Nissui" (MKII), and Fungitech G-test ES "Nissui" (ES).

RESULTS

A total of 163 participants were included. Among them, 32 cases of invasive mycosis, 34 cases with mycotic colonization infection, and 97 cases with non-fungal infections were confirmed. Regarding the diagnostic value of the commercial kits for invasive mycosis, the areas under the receiver operating characteristic curves were > 0.8 for all the agents. However, on the basis of the cut-off value set by the manufacturer, the sensitivity and specificity of the three kits for definitive invasive infection were 80.0% and 90.6% with Wako, 80.0% and 80.7% with MKII, and 86.7% and 71.8% with ES, respectively. Moreover, the rate of false-positive β-D-glucan elevation detection in patients with negative fungal culture was 9.3% with Wako, 18.6% with MKII, and 23.7% with ES.

CONCLUSION

Despite the high diagnostic value of β-D-glucan detection in invasive fungal infections, caution should be exercised in interpreting the value of the assay reagents.

Fungal biomarker monitoring and CT scans for early detection of invasive fungal disease in neutropenic hematological patients

OBJECTIVES

By using data from the CEDMIC trial (n = 413), we conducted a post-hoc analysis of the diagnostic value of biomarker monitoring and chest computed tomography (CT) scans for the early detection of invasive fungal disease (IFD) in neutropenic hematological patients.

METHODS

IFDs were defined in accordance with the EORTC/MSG definition with some modifications. Biomarkers such as Aspergillus galactomannan (GM) and (1→3)-β-D-glucan (βDG) were measured weekly.

RESULTS

The positive predictive value (PPV) of GM and βDG in cases of high-risk treatment were 0.70 and 0.69, while those in low-risk treatment were 0.08 and 0, respectively. All of the positive biomarkers that were measured before the development of fever in low-risk treatment were false positives. The proportion of patients who had abnormal chest CT findings was 19% in persistent fever at 4-6 days, 57% at 7 days or later and 36% in recurrent fever. Sixty-nine percent of the patients who had abnormal findings at 7 days or later did not have abnormalities at 4-6 days.

CONCLUSIONS

Afebrile screening of biomarkers in low-risk treatment is not useful. Chest CT should be reevaluated in persistent fever lasting for 7 days or longer even in patients who did not have abnormalities within 6 days.

Outstanding Contributions of LAL Technology to Pharmaceutical and Medical Science: Review of Methods, Progress, Challenges, and Future Perspectives in Early Detection and Management of Bacterial Infections and Invasive Fungal Diseases

The blue blood of the horseshoe crab is a natural, irreplaceable, and precious resource that is highly valued by the biomedical industry. The Limulus amebocyte lysate (LAL) obtained from horseshoe crab blood cells functions as a surprisingly sophisticated sensing system that allows for the extremely sensitive detection of bacterial and fungal cell-wall components. Notably, LAL tests have markedly contributed to the quality control of pharmaceutical drugs and medical devices as successful alternatives to the rabbit pyrogen test. Furthermore, LAL-based endotoxin and (1→3)-β-D-glucan (β-glucan) assay techniques are expected to have optimal use as effective biomarkers, serving as adjuncts in the diagnosis of bacterial sepsis and fungal infections. The innovative β-glucan assay has substantially contributed to the early diagnosis and management of invasive fungal diseases; however, the clinical significance of the endotoxin assay remains unclear and is challenging to elucidate. Many obstacles need to be overcome to enhance the analytical sensitivity and clinical performance of the LAL assay in detecting circulating levels of endotoxin in human blood. Additionally, there are complex interactions between endotoxin molecules and blood components that are attributable to the unique physicochemical properties of lipopolysaccharide (LPS). In this regard, while exploring the potential of new LPS-sensing technologies, a novel platform for the ultrasensitive detection of blood endotoxin will enable a reappraisal of the LAL assay for the highly sensitive and reliable detection of endotoxemia.

Candida Administration in Bilateral Nephrectomy Mice Elevates Serum (1→3)-β-D-glucan That Enhances Systemic Inflammation Through Energy Augmentation in Macrophages

Systemic inflammation, from gut translocation of organismal molecules, might worsen uremic complications in acute kidney injury (AKI). The monitoring of gut permeability integrity and/or organismal molecules in AKI might be clinically beneficial. Due to the less prominence of Candida albicans in human intestine compared with mouse gut, C. albicans were orally administered in bilateral nephrectomy (BiN) mice. Gut dysbiosis, using microbiome analysis, and gut permeability defect (gut leakage), which was determined by fluorescein isothiocyanate-dextran and intestinal tight-junction immunofluorescent staining, in mice with BiN-Candida was more severe than BiN without Candida. Additionally, profound gut leakage in BiN-Candida also resulted in gut translocation of lipopolysaccharide (LPS) and (1→3)-β-D-glucan (BG), the organismal components from gut contents, that induced more severe systemic inflammation than BiN without Candida. The co-presentation of LPS and BG in mouse serum enhanced inflammatory responses. As such, LPS with Whole Glucan Particle (WGP, a representative BG) induced more severe macrophage responses than LPS alone as determined by supernatant cytokines and gene expression of downstream signals (NFκB, Malt-1 and Syk). Meanwhile, WGP alone did not induced the responses. In parallel, WGP (with or without LPS), but not LPS alone, accelerated macrophage ATP production (extracellular flux analysis) through the upregulation of genes in mitochondria and glycolysis pathway (using RNA sequencing analysis), without the induction of cell activities. These data indicated a WGP pre-conditioning effect on cell energy augmentation. In conclusion, Candida in BiN mice accelerated gut translocation of BG that augmented cell energy status and enhanced pro-inflammatory macrophage responses. Hence, gut fungi and BG were associated with the enhanced systemic inflammation in acute uremia.

Prospective comparison of (1,3)-beta-D-glucan detection using colorimetric and turbidimetric assays for diagnosing invasive fungal disease

Serum (1→3)-β-D-glucan (BDG), an pan fungal antigen, is detected in some invasive fungal diseases (IFDs). We compared two commercial kits, the Fungitell assay (FA) (colorimetric) and the Wako assay (WA) (turbidimetric) over a 4-month period to prospectively test 171 patients who mainly had hematological conditions (62%) and experienced episodes (n = 175) of suspected invasive fungal infection. Twenty-three episodes due to BDG-producing fungi were diagnosed (pneumocystosis, n = 12; invasive aspergillosis, n = 5; candidemia, n = 3; invasive fusariosis, n = 2; hepato-splenic candidiasis, n = 1).Both assays provided similar areas under the curves (AUC = 0.9). Using the optimized positivity thresholds (≥120 pg/ml for FA and ≥ 4 pg/ml for WA), the sensitivity and specificity were 81.8% (CI95: 61.5-92.7), 94.8% (90.1-97.3) for FA and 81.8% (61.5-92.7), 95.4% (90.9-97.8) for WA. Negative predictive value was 97.3% (93.3-99.0) for both tests. If the manufacturer's positivity threshold (≥11 pg/ml) was applied, the WA sensitivity decreased to 50%. Among 71 patients with bacterial infections, 21.1% were FA-positive and 5.6% were WA-positive (p < 10-2).The WA performed similarly as compared to the FA with an optimized cutoff value. The WA is a single sample test that is clinically relevant when a prompt therapeutic decision is required.

LAY SUMMARY

Serum (1→3)-β-D-glucan testing is dominated by two kits including Fungitell colorimetric assay (FA) and the Wako turbidimetric assay (WA). We compared them prospectively and observed that they both perform similarly when selecting their optimal threshold (≥120 pg/ml for FA and ≥ 4 pg/ml for WA).

Circulating (1→3)-β-D-glucan Is Associated With Immune Activation During Human Immunodeficiency Virus Infection

BACKGROUND

Microbial translocation from the gut to systemic circulation contributes to immune activation during human immunodeficiency virus (HIV) infection and is usually assessed by measuring plasma levels of bacterial lipopolysaccharide (LPS). Fungal colonization in the gut increases during HIV-infection and people living with HIV (PLWH) have increased plasma levels of fungal polysaccharide (1→3)-β-D-Glucan (βDG). We assessed the contribution of circulating DG to systemic immune activation in PLWH.

METHODS

Cross-sectional and longitudinal assessments of plasma βDG levels were conducted along with markers of HIV disease progression, epithelial gut damage, bacterial translocation, proinflammatory cytokines, and βDG-specific receptor expression on monocytes and natural killer (NK) cells.

RESULTS

Plasma βDG levels were elevated during early and chronic HIV infection and persisted despite long-term antiretroviral therapy (ART). βDG increased over 24 months without ART but remained unchanged after 24 months of treatment. βDG correlated negatively with CD4 T-cell count and positively with time to ART initiation, viral load, intestinal fatty acid-binding protein, LPS, and soluble LPS receptor soluble CD14 (sCD14). Elevated βDG correlated positively with indoleamine-2,3-dioxygenase-1 enzyme activity, regulatory T-cell frequency, activated CD38+Human Leukocyte Antigen - DR isotype (HLA-DR)+ CD4 and CD8 T cells and negatively with Dectin-1 and NKp30 expression on monocytes and NK cells, respectively.

CONCLUSIONS

PLWH have elevated plasma βDG in correlation with markers of disease progression, gut damage, bacterial translocation, and inflammation. Early ART initiation prevents further βDG increase. This fungal antigen contributes to immune activation and represents a potential therapeutic target to prevent non-acquired immunodeficiency syndrome events.

The Presence of (1→3)-β-D-Glucan as Prognostic Marker in Patients After Major Abdominal Surgery

BACKGROUND

While the serological detection of (1→3)-β-D-glucan (BDG) can indicate invasive fungal disease (IFD), false positivity occurs. Nevertheless, the presence of BDG can still be recognized by the host's innate immune system and persistent BDG antigenemia, in the absence of IFD, can result in deleterious proinflammatory immune responses.

METHODS

During the XXX (INTENSE) study into the preemptive use of micafungin to prevent invasive candidiasis (IC) after abdominal surgery, the serum burden of BDG was determined to aid diagnosis of IC. Data from the INTENSE study were analyzed to determine whether BDG was associated with organ failure and patient mortality, while accounting for the influences of IC and antifungal therapy.

RESULTS

A BDG concentration >100 pg/mL was associated with a significantly increased Sequential Organ Failure Assessment score (≤100 pg/mL: 2 vs >100 pg/mL: 5; P < .0001) and increased rates of mortality (≤100 pg/mL: 13.7% vs >100 pg/mL: 39.0%; P = .0002). Multiple (≥2) positive results >100 pg/mL or a BDG concentration increasing >100 pg/mL increased mortality (48.1%). The mortality rate in patients with IC and a BDG concentration >100 pg/mL and ≤100 pg/mL was 42.3% and 25.0%, respectively. The mortality rate in patients without IC but a BDG concentration >100 pg/mL was 37.3%. The use of micafungin did not affect the findings.

CONCLUSIONS

The presence of persistent or increasing BDG in the patient's circulation is associated with significant morbidity and mortality after abdominal surgery, irrespective of IC. The potential lack of a specific therapeutic focus has consequences when trying to manage these patients, and when designing clinical trials involving patients where host-associated BDG concentrations may be elevated.

CLINICAL TRIALS REGISTRATION

NCT01122368.

Syk inhibitor attenuates inflammation in lupus mice from FcgRIIb deficiency but not in pristane induction: the influence of lupus pathogenesis on the therapeutic effect

Macrophages are responsible for the recognition of pathogen molecules. The downstream signalling of the innate immune responses against pathogen molecules, lipopolysaccharide (LPS) and (1→3)-β-D-glucan (BG), and the adaptive immune response to antibodies, Fc gamma receptor (FcgR), is spleen tyrosine kinase (Syk). Because pathogen molecules and antibodies could be presented in lupus, impact of Syk and macrophages in lupus is explored. FcgR-IIb deficient (FcgRIIb^-/-) mice, a model of inhibitory signalling loss, at 40 weeks old, but not pristane mice (a chemical induction lupus model) demonstrated spontaneous elevation of LPS and BG in serum from gut translocation despite the similarity in faecal microbiome analysis. Syk abundance in FcgRIIb^-/- mice was higher than in pristane mice, possibly due to several Syk activators (anti-dsDNA, LPS and BG), and Syk inhibitor-attenuated proteinuria and serum cytokines only in FcgRIIb^-/- mice. In addition, LPS + BG enhanced the expression of activating FcgRs, NF-κB and Syk, together with supernatant TNF-α predominantly in FcgRIIb^-/- compared to wild-type macrophages. The inhibitors against Dectin-1, Syk and nuclear factor kappa B, but not anti-Raf-1, reduced supernatant TNF-α in LPS+BG-activated macrophages, implying Syk-dependent signalling. The pathogen molecules enhanced activating-FcgRs, without inhibition, through Syk, a shared downstream innate and adaptive signalling, is responsible for the hyper-responsiveness in FcgRIIb^-/- macrophages. In conclusion, Syk inhibitor attenuated inflammation in FcgRIIb^-/- but not in pristane mice, implying the influence of a lupus genetic background in treatment modalities.

Diagnostic accuracy of (1→3)-β-D-glucan to predict Pneumocystis jirovecii pneumonia in non-HIV-infected patients

Background

Pneumocystis jirovecii pneumonia (PCP) is a common and potentially fatal opportunistic infection in immunocompromised non-HIV individuals. There are problems with clinical and diagnostic protocols for PCP that lack sensitivity and specificity. We designed a retrospective study to compared several methods that were used in diagnostics of PCP.

Patients and methods

One hundred and eight immunocompromised individuals with typical clinical picture for PCP and suspicious radiological findings were included in the study. Serum samples were taken to measure the values of (1→3)-β-D-glucan (Fungitell, Associates of Cape Cod, USA). Lower respiratory tract samples were obtained to perform direct immunofluorescence (DIF, MERIFLUOR® Pneumocystis, Meridian, USA) stain and real-time PCR (qPCR).

Results

Fifty-four (50%) of the 108 patients in our study had (1→3)-β-D-glucan > 500 pg/ml. Patients that had (1→3)-β-D-glucan concentrations < 400 pg/ml in serum, had mean threshold cycles (Ct) 35.43 ± 3.32 versus those that had (1→3)-β-D-glucan concentrations >400 pg/mL and mean Ct of 28.97 ± 5.27 (P < 0.001). If we detected P. jirovecii with DIF and qPCR than PCP was proven. If the concentration of (1→3)-β-D-glucan was higher than 400 pg/ml and Ct of qPCR was below 28.97 ± 5.27 than we have been able be certain that P. jirovecii caused pneumonia (odds ratio [OR] 2.31, 95% confidence interval [CI] 1.62–3.27, P < 0.001).

Conclusions

Measurement of (1→3)-β-D-glucan or qPCR alone could not be used to diagnose PCP. Diagnostic cut-off value for (1→3)-β-D-glucan > 400pg/ml and qPCR below 30 Ct, allow us to conclude that patient has PCP. If the values of (1→3)-β-D-glucan are < 400 pg/ml and qPCR is above 35 Ct than colonization with P. jirovecii is more possible than PCP.

Low Molecular-Weight Curdlan, (1→3)-β-Glucan Suppresses TLR2-Induced RANKL-Dependent Bone Resorption

Fungal β-glucan is a potent immunological stimulator, and that it activates both the innate immune system and adaptive immunity. Curdlan is (1→3)-β-glucan, a linear form of β-glucan with a high molecular weight; it modulates the immune response. However, its role in bone tissue is controversial, and the effects of curdlan on bone tissues are unknown. Toll-like receptors (TLRs) play critical roles in innate immunity, and various ligands for TLRs are thought to regulate the host defense mechanisms against pathogens. TLR2 is known to form heterodimers with TLR6, and the TLR2-TLR6 heterodimer (TLR2/6) recognizes diacylated lipopeptides from Gram-positive bacteria. In the present study, we prepared low molecular-weight curdlan, (1→3)-β-D-glucan, and examined its effects on bone resorption induced by TLR2/6 signaling. In co-cultures of bone marrow cells and osteoblasts, low molecular-weight curdlan suppressed the osteoclast formation induced by TLR2/6 ligand, and attenuated bone resorption in mouse calvarial organ cultures. Curdlan acted on mouse osteoblasts and suppressed the expression of receptor activator of nuclear factor-kappa B (NF-κB) ligand (RANKL), a key molecule for osteoclastogenesis. Curdlan also acted on mouse bone marrow macrophages and suppressed RANKL-dependent osteoclast differentiation from osteoclast precursor cells. The present study indicates that low molecular-weight curdlan attenuated TLR2-induced inflammatory bone resorption. Curdlan, (1→3)-β-glucan may be a natural agent with beneficial effects on bone health in humans.

Catheter-related bloodstream infection due to Rhodotorula mucilaginosa with normal serum (1→3)-β-D-glucan level

Rhodotorula species are environmental basidiomycete yeasts that have emerged as a cause of fungemia in immunocompromised hosts. The insertion of a central venous catheter was identified as a major risk factor for Rhodotorula fungemia. Few cases reports have reported (1→3)-β-D-glucan testing at the onset of Rhodotorula mucilaginosa fungemia. We report a case of catheter-related bloodstream infection due to R. mucilaginosa. Serum β-D-glucan level was normal at the onset of the bloodstream infection. It took 5 days to culture the isolate. The patient's fever persisted after empiric treatment with micafungin, and a switch to oral voriconazole immediately resolved the fungemia.

Serum (1→3)-β-D-glucan and galactomannan levels in patients with cystic fibrosis: a retrospective cohort study

Background

Aspergillus fumigatus is frequently encountered in sputum samples of patients with cystic fibrosis (CF), which traditionally has been interpreted as saprophytic airway colonization. However, this mere bystander role has been challenged by recent data. There is now evidence that Aspergillus fumigatus accelerates the decline of pulmonary function.

(1→3)-β-D-glucan (BDG) and galactomannan (GM) are highly sensitive fungal biomarkers that are used to diagnose invasive fungal disease. However, their diagnostic value in CF patients is largely unknown.

Methods

We conducted a retrospective cohort study on 104 CF patients to determine whether serum BDG and GM levels correlate with parameters such as Aspergillus-positive sputum cultures and lung function.

Results

Aspergillus fumigatus was persistently detected in 22 of the 104 CF patients (21%). Mean serum BDG and GM levels in the Aspergillus-positive patients were significantly higher than in those without persistent Aspergillus detection (89 versus 40 pg/ml [p = 0.022] and 0.30 versus 0.15 ODI [p = 0.013], respectively). 27 and 7 patients had elevated BDG (≥ 60 pg/ml) or GM levels (> 0.5 ODI), respectivly. BDG and GM levels showed a significant correlation (p = 0.004). Patients with increased serum concentrations of BDG were more frequently Aspergillus-positive (40.7 versus 14.3%, p = 0.004) and had a significantly lower forced expiratory volume in one second (FEV1) than patients with a normal BDG (61.6 versus 77.1%, p = 0.007). In the multivariate analysis, BDG but not GM or the growth of A. fumigatus, proved to be an independent predictor for the FEV1.

Conclusions

CF patients with persistent Aspergillus detection have elevated BDG and GM levels which ranged between healthy and invasively infected patients. Serum BDG may be superior to GM and fungal culture in predicting an impaired lung function in CF patients.

The Synergy of Endotoxin and (1→3)-β-D-Glucan, from Gut Translocation, Worsens Sepsis Severity in a Lupus Model of Fc Gamma Receptor IIb-Deficient Mice

We investigated the influence of spontaneous gut leakage upon polymicrobial sepsis in a lupus model with Fc gamma receptor IIb-deficient (FcGRIIb-/-) mice aged 8 and 40 weeks, as representing asymptomatic and symptomatic lupus, respectively. Spontaneous gut leakage, determined by (i) the presence of FITC-dextran, (ii) elevated serum endotoxin, and (iii) elevated serum (1→3)-β-D-glucan (BG), was demonstrated in symptomatic lupus but not in the asymptomatic group. In parallel, spontaneous gut leakage, detected by elevated serum BG without fungal infection, was demonstrated in patients with active lupus nephritis. Gut leakage induced by dextran sulfate solution (DSS) or endotoxin administration together with BG or endotoxin alone, but not BG alone, enhanced the severity of cecal ligation and puncture (CLP) sepsis more prominently in 8-week-old FcGRIIb-/- mice. Additionally, the bone marrow-derived macrophages of FcGRIIb-/- mice produced higher cytokine levels when coexposed to endotoxin and BG, when compared to wild-type mice. In summary, spontaneous gut leakage was demonstrated in symptomatic FcGRIIb-/- mice and the induction of gut permeability worsened sepsis severity. Gut translocation of endotoxin and BG had a minor effect on wild-type mice, but the synergistic effect of BG and endotoxin was prominent in FcGRIIb-/- mice. The data suggest that therapeutic strategies addressing gut leakage may be of interest in sepsis conditions in patients with lupus.

Successful treatment of Aspergillus ventriculitis through voriconazole adaptive pharmacotherapy, immunomodulation, and therapeutic monitoring of cerebrospinal fluid (1→3)-β-D-glucan

Aspergillus ventriculitis is an uncommon but often fatal form of invasive aspergillosis of the central nervous system (CNS). As little is known about the diagnosis, treatment, and outcome of this potentially lethal infection, we report the strategies used to successfully treat Aspergillus ventriculitis complicating a pineal and pituitary germinoma with emphasis on the critical role of adaptive pharmacotherapy of voriconazole and serial monitoring of (1→3)-β-D-glucan in cerebrospinal fluid. We describe several rationally based therapeutic modalities, including adaptive pharmacotherapy, combination therapy, sargramostim-based immunomodulation, and biomarker-based therapeutic monitoring of the CNS compartment. Through these strategies, our patient remains in remission from both his germinoma and Aspergillus ventriculitis making him one of the few survivors of Aspergillus ventriculitis.

Evaluation of gastrointestinal leakage using serum (1→3)-β-D-glucan in a Clostridium difficile murine model

Gastrointestinal (GI) leakage in Clostridium difficile-associated diarrhea (CDAD) is well known but is not routinely assessed in clinical practice. Serum (1→3)-β-D-glucan (BG), a fungal cell wall component used as a biomarker for invasive fungal disease, was tested in a CDAD mouse model with and without probiotics. Higher serum fluorescein isothiocyanate-dextran (FITC-dextran) and spontaneous gram-negative bacteremia, GI leakage indicators, were frequently found in CDAD mice, which died compared with those which survived. BG, serum macrophage inflammatory protein-2 and FITC-dextran but not quantitative blood bacterial count differentiated the clinical severity. Interestingly, a specific dose of Lactobacillus rhamnosus L34 attenuated CDAD and decreased serum BG and FITC-dextran, but not other parameters. BG also showed a higher area under the receiver operating characteristic curve for 7-day mortality than FITC-dextran. Fifty-five percent of CDAD mice with BG ≥ 60 pg/ml (the human negative cut-off value for invasive fungal disease) at 1 day after C. difficile gavage died within 7 days. In conclusion, S: erum BG was elevated in mice with severe CDAD, an established model of GI leakage with a strong association with mortality rate. BG monitoring in patients with CDAD is of interest as both a potential prognostic tool and a therapeutic efficacy indicator.

(1→3)-β-D-glucan and galactomannan testing for the diagnosis of fungal peritonitis in peritoneal dialysis patients, a pilot study

Fungal peritonitis is an uncommon but serious complication of peritoneal dialysis (PD) due to the fact that routine culture to recovered the etiologic agents are time consuming and KOH staining has very low sensitivity. Peritoneal (1→3)-β-D-glucan (BG) or galactomannan (GM), both fungal cell wall components, are candidate biomarkers of fungal peritonitis. Hence, a comparative cross-sectional analysis of peritoneal dialysis fluid (PDF) BG (Fungitell, Cape Cod, MA, USA) and GM (Platelia Aspergillus Ag kits, Bio-rad, France) from all PD patients with and without fungal peritonitis (13 cases, identified by culture), over a 1 year period, was performed. PDF of the fungal peritonitis group showed very high BG (494 ± 19 pg/ml) and high GM (3.41 ± 1.24) similar results were noted in specimens from cases of peritonitis with other causes, especially gram negative bacterial peritonitis. A BG cut-off value at 240 pg/ml and GM at 0.5 showed sensitivity/ specificity at 100%/ 83% and 77%/ 58%, respectively. A concomitantly positive GM reduced the false positive rate of BG from nonfungal peritonitis. In conclusion, BG and GM in peritoneal fluid with provisional cut-off values were applicable as surrogate biomarkers for the diagnosis of fungal peritonitis in PD patients.

Outdoor (1→3)-β-D-glucan levels and related climatic factors

Objectives

To evaluate the monthly variation in the airborne (1→3)-β-D-glucan level throughout one year and its relationship with climatic factors (temperature, relative humidity, wind speed, hours of daylight, cloud cover, and pollen counts).

Methods

A total of 106 samples were collected using a two-stage cyclone sampler at five outdoor sampling locations (on top of 5 university buildings). The kinetic limulus amebocyte lysate assay was used to obtain (1→3)-β-D-glucan levels.

Results

Airborne (1→3)-β-D-glucan levels were significantly higher in the spring, particularly in April, and temperature was significantly related to (1→3)-β-D-glucan levels (r =0.339, p<0.05).

Conclusions

(1→3)-β-D-glucan levels may be highest in the spring, and outdoor temperature may influence (1→3)-β-D-glucan levels.