Mycopathologia最新文献

Background: Pneumocystis jirovecii pneumonia (PjP) is a life-threatening infection in immunocompromised individuals. Its diagnosis remains challenging, especially in microscopy-negative cases. This study aimed to standardize and validate a qPCR assay targeting the mtLSU rRNA gene for detecting P. jirovecii DNA in respiratory samples from patients in Argentina.

Materials and methods: The assay was optimized using plasmid dilutions containing the target gene. Analytical specificity was evaluated against 60 fungal, 21 mycobacterial, and 16 bacterial species. Clinical validation included 101 respiratory samples from symptomatic patients and 37 from healthy individuals. An internal positive control (IPC) was included in all reactions to detect inhibitors.

Results: The qPCR assay showed a detection limit of 8.8 copies/μL and no cross-reactivity. Among microscopy-confirmed cases, 95.5% were qPCR-positive. Notably, 14.9% of microscopy-negative but clinically compatible cases tested positive. ROC analysis yielded an AUC of 0.96, with an optimal Ct cutoff ≤ 36, providing 90.7% sensitivity and 95.8% specificity. No healthy controls tested positive. A "grey zone" (Ct 36-37.8) was observed, requiring clinical correlation.

Conclusions: This qPCR assay is highly sensitive and specific, offering a valuable diagnostic tool for PjP. Its performance supports implementation in routine diagnostics, especially when microscopy is inconclusive. However, interpretation in the grey zone requires complementary clinical or biomarker data.

The dermatophytes, classified in a single family Arthrodermataceae (Onygenales). This family has received more attention due to their keratin-degrading properties and the ability of some taxa to invade the skin and cause dermatophytes in humans and/or mammals. The phylogeny of Arthrodermataceae is remarkably stable, with Arthroderma representing the ancestral geophilic lineage and Trichophyton constituting a derived clade of anthropophiles and some zoophiles. The other genera appear to represent intermediate forms along this ecological spectrum. During a survey of Arthrodermataceae in China, a geophilic species was isolated. A multi-locus phylogenetic analysis of three markers (ITS, β-tubulin, and tef1-α) reveals that this taxon is a sister species to Arthroderma cuniculi. It can be differentiated from other species in Arthroderma by two types of microconidia: (i) smooth-walled, cylindrical to clavate, (ii) smooth-walled, obovate to pyriform. Phylogenetic analyses, and morphology provide evidence that the new isolate is a distinct species. This study enriches the Arthroderma species inventory and expands our understanding of dermatophyte biodiversity.

We retrospectively analyzed 99 cases of zoonotic dermatophytosis diagnosed by culture over a 10-year period at a dermatological clinic. Microsporum canis was the most frequently isolated species (89 cases), followed by Trichophyton verrucosum (4 cases), T. mentagrophytes (4 cases), T. benhamiae (1 case), and T. erinacei (1 case). Patients < 15 years of age accounted for 31.3% of the cases. Tinea corporis was the predominant clinical form, with frequent facial and upper-extremity involvement. Topical corticosteroid misuse was noted in 37 patients, and multiple family members were affected in 20 cases. M. canis infections were mostly linked to cats, including stray cats and adopted shelter cats. Infections caused by T. benhamiae and T. erinacei were traced to guinea pigs and hedgehogs, respectively. These findings highlight diagnostic challenges and emerging animal reservoirs. The One Health approach requires active surveillance and education across human and animal health.

Introduction: Pneumocystis jirovecii pneumonia (PJP) is one of the leading causes of mortality in kidney transplant recipients. Identifying risk factors for mortality in high-risk patients is essential for developing timely and proactive treatment strategies.

Materials and methods: We conducted a retrospective analysis of clinical data from kidney transplant recipients who developed PJP progressing to acute respiratory distress syndrome. Baseline patient demographics, laboratory parameters on admission, and especially absolute lymphocyte count (ALC) levels within the first week of hospitalization were collected, along with follow-up data on patient outcomes. We analyzed ALC trajectory to define persistent lymphopenia and employed logistic regression to identify predictors of all-cause in-hospital mortality. A clinical prediction model was subsequently developed and evaluated using a range of performance metrics.

Results: Based on clinical indicators observed after admission, we defined persistent lymphopenia as an ALC below 400/μL for at least four consecutive days. In-hospital mortality was significantly higher in patients with persistent lymphopenia. Logistic regression analysis identified persistent lymphopenia, the C-reactive protein to albumin ratio, and the PaO₂/FiO₂ ratio as significant risk factors for in-hospital mortality. The clinical prediction model constructed from these variables exhibited excellent diagnostic performance and clinical applicability.

Conclusion: Persistent lymphopenia is a significant risk factor for patient mortality, and the clinical prediction model based on this factor demonstrates good diagnostic performance and clinical applicability.

Eumycetoma is a neglected tropical disease caused primarily by a Madurella mycetomatis infection, besides other related species. In this study, we designed a novel loop-mediated isothermal amplification (LAMP) primer set capable of simultaneously detecting four Madurella species (M. mycetomatis, M. pseudomycetomatis, M. tropicana, and M. fahalii). Genomic sequencing of M. pseudomycetomatis strain and comparative genome analysis revealed the candidate genes that were common among and specific to Madurella species. The 3 LAMP primer sets targeting these genes detected up to 1 pg of the genomic DNA of all 4 Madurella species, exhibiting no cross-reactivity toward other pathogenic fungi. Among these, one primer set showing better reactivity was selected as a candidate used for diagnosis. Therefore, we developed novel primer sets which enabled the simultaneous detection of four Madurella species. Our present findings will lead to a faster and simpler diagnostic tool for eumycetoma detection, especially in rural clinical settings.

Invasive fungal infections constitute a major cause of morbidity and mortality in children, affecting mainly those with malignancies and immunodeficiencies (primary or secondary), who receive solid or hematopoietic stem cell transplantation, and those in neonatal or pediatric intensive care units. Overuse and inappropriate prescription of antifungal (AF) agents have been reported in pediatrics, leading not only to an increase in adverse events and toxicities but also to the development of AF resistance. AF stewardship practices as part of broader antimicrobial stewardship programs are crucial for improving outcomes and reducing AF overuse and associated costs. This review has two main objectives: to summarize the published data on prescription patterns of AF agents in pediatrics and to describe the current state of pediatric AF stewardship programs worldwide, providing suggestions for their implementation. Given the significant burden of invasive fungal infections in vulnerable pediatric populations, identification of actions to improve AF stewardship practices in real-life clinical settings is essential.

Rationale: The antifungal armamentarium is shrinking while resistance to licensed agents rises. Historically, actinomycetes and fungi delivered nystatin, amphotericin B, griseofulvin and the echinocandin scaffold, yet plant-derived compounds-despite potent in-vitro activity-have rarely reached the clinic.

Objective: To frame the recent in-vivo success of papaya-seed essential oil against fluconazole-sensitive and -resistant Candida albicans within the broader context of plant-based antifungal discovery, and to propose rigorous criteria that can accelerate translation, especially considering varying resource settings.

Key points: Commentary on Ma et al. (Mycopathologia 190(5):1-14, 2025) showing that benzyl-isothiocyanate-rich papaya-seed oil outperforms fluconazole in a murine systemic candidiasis model without acute toxicity; Historical perspective on how soil microbes provided the first broad-spectrum antifungals; An eight-point checklist for future plant-extract studies, with essential and suggested elements to promote high-quality research across different laboratory settings.

Conclusion: Adherence to core methodological standards, along with suggested advanced analyses where feasible, will help identify promising plant-derived antifungal leads and support a more inclusive and effective discovery pipeline.

Aspergillus fumigatus, an opportunistic and allergenic pathogenic fungus, is responsible for a range of clinical disorders in humans, including invasive aspergillosis (IA), which can lead to severe infections in immunocompromised individuals. Unfortunately, the emergence of azole resistance has become a significant challenge in combating IA, necessitating further investigations into the underlying mechanisms of resistance. In this study, we conducted an integrated proteomic and phosphoproteomic analysis of biofilm proteins from both azole-resistant and wildtype strains of A. fumigatus under voriconazole pressure. Our proteomic analysis identified 148 upregulated and 146 downregulated proteins in the azole-resistant strains, while phosphoproteomic analysis revealed 316 upregulated phosphopeptides and 109 downregulated phosphopeptides, suggesting extensive phosphorylation modifications associated with azole resistance. Upon excluding the impact of protein changes, we identified 133 proteins with differential expression solely at the phosphorylation level, comprising 104 upregulated and 29 downregulated proteins. Functional annotation and analysis highlighted the significance of these differentially expressed phosphoproteins in cell wall integrity, filamentous growth, and high-osmolarity stress response, with 33 MAPK pathway-associated proteins displaying phosphopeptide level regulation. These findings provide valuable insights into the mechanisms behind azole resistance in A. fumigatus and offer potential new drug targets for combating this pathogenic fungus in humans.

This study evaluates and compares the diagnostic and prognostic capabilities of ChatGPT-4o and DeepSeek-R1 in 56 HIV-negative talaromycosis cases. Clinical case fragments were de-identified and submitted to both models, with diagnostic accuracy and prognostic prediction rates statistically analyzed using chi-square tests, Fisher's exact tests, and logistic regression. Results showed DeepSeek-R1 achieved significantly higher diagnostic accuracy (66.1%) than ChatGPT-4o (3.6%) (χ² = 48.2, p < 0.001), attributable to its regional data training focusing on Southeast Asia and southern China. Conversely, ChatGPT-4o demonstrated superior prognostic prediction accuracy (78.6% vs. 50.0%, p < 0.001), with 90.2% specificity for improved (survival) outcomes, while DeepSeek-R1 showed 86.7% sensitivity for mortality. Key diagnostic predictors included hilar lymphadenectasis (odds ratio [OR] = 6.8, 95% confidence interval [CI]: 2.1-22.3, P = 0.002) and chest pain (OR = 5.9, 95% CI: 1.4-25.6, P = 0.016). The findings highlight DeepSeek-R1's regional diagnostic advantage and ChatGPT-4o's prognostic utility, advocating for their collaborative use to enhance early detection and management of this neglected fungal infection in immunocompromised, non-HIV populations.