Mycopathologia最新文献

Abdominal aortic aneurysm (AAA) is a life-threatening vascular condition characterized by inflammatory degeneration of the vessel wall. Emerging evidence suggests that microbial factors contribute to its progression. In this study, we analyzed the mycobiome composition of stool, blood, thrombus and damaged vessel wall samples collected during surgery from 24 AAA patients using Internal Transcribed Spacer (ITS) sequencing. Significant differences in alpha and beta diversity were observed across the sample types, confirming compartmentalization of the mycobiome. However, individual fungal profiles did not establish a clear gut-blood-vessel wall axis, indicating that fungi translocated to the vessel wall may originate from other anatomical regions. Comparison AAA mycobiome with healthy arterial walls' mycobiome from organ donors revealed a dominance of anti-inflammatory Tomentella in healthy samples, while pro-inflammatory Malassezia species were prevalent in damaged vessel walls. These findings highlight the role of fungi in AAA progression and suggest potential thera-peutic avenues, including antifungal adjuvant treatments to mitigate inflammation and aneurysm development.

Candidiasis, traditionally dominated by Candida albicans infection, now faces a paradigm shift with the emergence of non-C. albicans infections, such as the multidrug-resistant (MDR) Candidozyma (formerly Candida) species. Critically, the emergence of multidrug resistance (MDR) Candidozyma duobushaemulonii (also known as Candida duobushaemulonii) poses critical challenges to antifungal therapy. Here, in this comparative study, we analyzed four clinical C. duobushaemulonii isolates (cd, cd1, cd2, and cd3) to establish strain-specific virulence and antifungal resistance profiles. Biofilm quantification using crystal violet (CV) and 2,3-Bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) metabolic activity assays showed different biomass production levels across strains. Cellular aggregation capacity differed significantly, while cell surface hydrophobicity (CSH) showed inverse patterns. In Galleria mellonella infection models, virulence stratification was observed. Antifungal susceptibility testing revealed minimum inhibitory concentration (MIC) azole gradients. MDR in the cd1 strain extended to 5-fluorocytosine (5-FC) and anidulafungin (ANI), whereas the cd3 strain showed intermediate posaconazole (PSZ) resistance distinct to the cd2 strain. Amino acid sequence analyses indicated that Y132F substitutes in ERG11 and D139N in FUR1 genes occurred in cd and cd1 strains. Gene expression analysis recorded various regulatory situations among strains. These analyses provide a complete resistance-virulence matrix for C. duobushaemulonii, establishing baseline characteristics for epidemiological surveillance and a reference framework for future comparative studies.

Scedosporium species are opportunistic pathogens causing a large variety of human infections. To date, there is limited information on the pathogenic mechanisms of these fungi, partly because of the limited number of genetic tools available. Here, the CRISPR-Cas9 technology, which provided promising results for functional genomic studies in filamentous fungi, was optimized for Scedosporium species using in vitro assembled Cas9 ribonucleoprotein (RNP) complexes. In these fungi, functional genomic studies are particularly complex in a wild-type strain, because of the high frequency of non-homologous recombination. Prior disruption of the KU70 gene encoding one of the components of the non-homologous end joining system is required, which necessitates the use of a first selection marker. The cleavage of the target gene at each end using a dual RNA-guided Cas9 complex, followed by recombination with a repair template containing the hygromycin resistance gene, allowed disruption of the target gene in the ΔKU70 mutant. Four genes encoding dioxygenases, catalyzing the critical ring-opening step in aromatic hydrocarbons, were successfully disrupted, and the optimum efficiency was observed using 5 μg of the HygR repair cassette. Alternatively, in the wild-type strain, the exclusive use of two Cas9 RNP complexes was enough to achieve an efficient deletion method; one dioxygenase gene was successfully deleted in up to 20% of the obtained colonies. These last experimental conditions path the way to multiple gene deletions and complementation experiments, which cannot be reached using our first procedure since only two selection markers are available for Scedosporium species.

Introduction: Invasive pulmonary aspergillosis (IPA) in hematological malignancy populations has high mortality rates. While there are identified prognostic factors for mortality, conflicting results are reported from the studies including bronchoalveolar lavage galactomannan (GM) measurements and co-infections. We aimed to evaluate risk factors associated with in-hospital mortality in a hematological malignancy population undergoing bronchoscopy with a preliminary diagnosis of IPA in a single tertiary care center.

Method: Patients undergoing bronchoscopy with a preliminary diagnosis of IPA were included in this retrospective study. Bacterial co-infection was defined as a positive bacterial culture in respiratory samples within ± 7 days of the index bronchoscopy procedure.

Results: Study population consisted 305 patients diagnosed as possible, probable or proven IPA. 57 patients presented with fungal and bacterial co-infection. In-hospital mortality was observed in 98 (33.6%) patients. Patients with mortality status were older and were not in remission for hematological malignancy. Serum GM, bronchoalveolar lavage (BAL) GM and bronchial lavage (BL) GM levels showed a significant relation with in-hospital mortality but weak accuracy. In multivariate analysis for risk factors of in-hospital mortality; age, remission status, number of nodules in HRCT and having fungal infections with or without combined bacterial infection were independent risk factors.

Conclusion: Co-infections in this susceptible population should not be overlooked even in the presence of fungal infection evidence. BAL and BL GM tended to have a stronger relation with survival than serum GM measurements taken at the same time. The number of nodules in radiological assessment might be an indicator of mortality. Radiological changes through the disease course might be assessed in further studies.

Background and aims: Invasive cutaneous fungal infections (ICFIs) are life-threatening complications in pediatric cancer patients. This study aimed to investigate the prevalence, clinical characteristics, and outcomes of ICFIs among pediatric cancer patients hospitalized at a referral oncology teaching Hospital in Shiraz, Iran.

Methods: This cross-sectional study included pediatric patients with malignancies and suspected ICFIs who were admitted to the Amir Oncology Teaching Hospital between 2015 and 2022. Diagnosis was based on the EORTC/MSG criteria and confirmed using clinical, microbiological, and histopathological methods. Data were analyzed using descriptive statistics, Kaplan-Meier survival analysis, and comparative tests, with a significance threshold of p < 0.05.

Results: Among the 24 patients, 58.3% were boys, and 45.8% were aged 1-5 years. Acute lymphoblastic leukemia was the most common malignancy (27.3%). Mucoralean fungi (36.4%) and Aspergillus (59.1%) were the most common. The overall survival rate was 54.2%. Proven ICFIs had the poorest outcomes, with a survival probability declining to zero by month 26. Patients with lower CRP levels and febrile neutropenia had better outcomes (p < 0.001 and p = 0.041, respectively), but survival rates did not vary significantly according to sex, age, or treatment approach (monotherapy versus combination therapy).

Conclusion: In pediatric oncology patients, ICFIs are associated with high mortality, particularly in cases of mucormycosis or proven infections. Improving survival depends on early diagnosis, risk stratification, and rapid management, particularly in patients with neutropenia and fever.

The whole-genome sequencing of two Candida auris isolates from the skin lesions of a Korean head and neck atopic dermatitis patient classified them within clade II. The isolates were susceptible to common antifungals. This study provides valuable genomic data for understanding the epidemiology and antifungal response of this emerging pathogen.

Background: Candidemia is a severe systemic infection with a high mortality risk. While β-D-glucan (BDG) serves as a diagnostic biomarker, its prognostic value in candidemia, particularly in association with Candida bundle compliance, remains unclear.

Methods: In this retrospective multicenter cohort study, we evaluated 96 patients with candidemia across nine Japanese hospitals between 2016 and 2023. Candida bundle compliance was assessed using five key components: central venous catheter removal within 24 h of diagnosis, appropriate initial antifungal therapy, ophthalmologic examination, follow-up blood cultures until clearance, and antifungal therapy for at least two weeks post-clearance. Analyses stratified patients by serum BDG status (positive/negative) and compliance with the Candida bundle (high: 4-5 points; low: 0-3 points). The primary outcome was 30-day mortality, and the secondary outcome was defined as endophthalmitis incidence.

Results: Of 96 eligible patients with candidemia, 70 (72.9%) were BDG-positive and 26 (27.1%) were BDG-negative. The overall 30-day mortality was 17.7%. Among BDG-positive patients, 15 (21.4%) died, while 2 (7.7%) died in BDG-negative cohorts (p = 0.09). Serum BDG positivity demonstrated a statistically significant association with decreased survival rates in the low bundle adherence group (p = 0.02), whereas this correlation was not observed among patients in the high-compliance cohort (p = 0.66). Endophthalmitis occurred in 25.0% of patients, without significant correlation to serum BDG status. C. albicans was associated with a significantly higher incidence of endophthalmitis compared with non-albicans species (45.7% vs. 8.9%).

Conclusions: Serum BDG positivity potentially correlates with worse survival in candidemia, particularly in patients with low bundle compliance. This emphasizes the importance of adherence to standardized Candida management protocols for optimizing patient outcomes.

Background: The utility of polymerase chain reaction (PCR) for diagnosing mucormycosis is uncertain. We conducted a diagnostic test accuracy meta-analysis to determine the performance of Mucorales PCR.

Methods: We systematically reviewed PubMed, Embase, and Cochrane Central databases to identify studies reporting Mucorales PCR (blood or bronchoalveolar lavage fluid [BALF] samples) in at least 10 suspected mucormycosis cases. We pooled sensitivity and specificity using Bayesian (weak and two informative priors) and frequentist methods. Subgroup analyses included middle vs. high-income countries, risk factors (hematological diseases vs. others), study design, assay type (commercial vs. in-house), and testing protocol (serial testing vs. single-time PCR). We assessed the effect of the number of blood tests performed per participant on sensitivity using multivariable meta-regression.

Results: We identified 1524 citations, of which 36 studies (41 datasets, n = 6627 participants; 16,613 samples) were included. The pooled sensitivity and specificity (with 95% credible interval) by Bayesian weak priors (primary analysis) were 51% (34-67%) and 97% (95-98%) for blood; 64% (50-76%) and 97% (95-98%) for BALF samples. We found wide variation in sensitivity, with a 14% increment for every additional blood sample tested per patient. Studies from middle-income countries reported a significantly lower pooled sensitivity (31 vs. 68%) in blood samples and lower specificity in BALF (72 vs. 98%) than high-income countries. No other subgroups showed significant differences.

Conclusion: Mucorales PCR was highly specific but poorly sensitive in blood, and moderately sensitive with high specificity in BALF. Before routine implementation, further well-designed studies from diverse settings and underrepresented regions are needed.