Mycopathologia最新文献

Chronic colonization by filamentous fungi in patients with cystic fibrosis (pwCF) is linked to declines in lung function and quality of life. To better assess indoor mold exposure, 23 French dwellings of pwCF from CF care centers in Normandy and Maine & Loire, France were visited. Bioaerosols collected using Coriolis® µ and Coriolis® compact biocollectors and dust were cultured on four different media: Potato Dextrose Agar (PDA), Malt Extract Agar (MEA), Sabouraud Chloramphenicol Gentamicin (SCG) and Sabouraud Chloramphenicol Gentamicin Actidione (S +). A total of 164 fungal species were identified (44 in both air and dust, 77 in air only and 43 in dust only), with no significant difference in average species count between air and dust samples (p = 0.353). The Coriolis® µ biocollector yielded significantly higher species recovery and fungal load from air samples compared to the Coriolis® compact biocollector (p < 0.001 and p < 0.0001, respectively). Higher CFU/m³ for Aspergillus, Fusarium, Mucor and Rhizopus were found on MEA, PDA and SCG media compared to S + (p = 0.037, p = 0.005 and p = 0.030, respectively). Alpha diversity was also greater on MEA, PDA and SCG media than on S + medium (p = 0.001, p < 0.0001 for PDA and SCG) and PDA than on MEA (p = 0.008). The distribution of common fungal genera was consistent with literature, except for higher frequencies of Fusarium and Talaromyces in our study. In conclusion, air sampling with the Coriolis® µ biocollector and inoculation on PDA or MEA media is recommended for this type of field study.

The dermatophyte Trichophyton rubrum is the primary causative agent of a cutaneous disease known as dermatophytosis. To establish an infection, this fungus coordinates many mechanisms related to biochemical processes, physiological adaptation, and transcriptional networks. Transcription factors (TFs) are the main proteins that elicit biological responses when T. rubrum interacts with keratinized tissues and promotes defense responses to prevent fungal colonization. In this study, we investigated the role of the TF StuA, a recently described T. rubrum protein, in controlling this fungal transcriptional program in response to glucose and keratin. This approach, based on RNA sequencing data, revealed at least 33 TF genes differentially expressed in glucose or keratin. We also showed that StuA regulates the pH signaling transcription factor, PacC, a relevant TF recruited for keratin assimilation in T. rubrum. Furthermore, we demonstrated that StuA modulates positively pacC and influences alternative splicing events of pacC transcripts in keratin cultures. Our findings revealed that StuA represses pacC transcription in a co-culture with keratinocytes and modulates the expression of the pal pathway genes, besides suggesting that StuA is pivotal for pH recognition responses and nutrient assimilation in the host. As a follow-up study, our results shed light on discovering new targets to treat dermatophytosis and elucidating transcriptional networks that are fundamental to T. rubrum pathogenesis.

Trichosporon spp. are ubiquitous environmental and emerging opportunistic fungi that can be part of the normal microbiota of the skin, vagina, and gastrointestinal tract in humans and other animals. In a state of microbiota imbalance, both immunocompromised and non-immunocompromised patients are susceptible to trichosporonosis, which can present as either superficial infections, such as White Piedra, or deep-seated infections, such as fungemia. Due to intrinsic resistance or limited efficacy reported with fluconazole, polyenes, echinocandins, and flucytosine, voriconazole is currently recommended in clinical guidelines. Biofilm formation and the overexpression of efflux pumps may contribute to this limited efficacy, but other resistance mechanisms have also been reported. The high antifungal resistance levels present in this genus highlight the urgent need for new therapeutic approaches and a better understanding of Trichosporon pathogenesis and the molecular mechanisms underlying this resistance. In this review, we discuss antifungal resistance and the mechanisms of this resistance in Trichosporon spp., addressing key points that require further investigation.

Background: Candida auris, a medically multidrug-resistant fungal pathogen, has recently emerged as the primary one that poses a global public health threat. Although C. auris was first described in Japan, numerous cases of C. auris infections have been reported globally and clustered in four major clades (I, II, III, and IV). In 2019 and 2024, a potential V clade in Iran and VI clade in Bangladesh were described. Nevertheless, limited pathogenicity data of the fifth clade are available compared to the other clades.

Objectives and methods: This study evaluated the pathogenicity of fluconazole-resistant C. auris clade V and the therapeutic efficacy of amphotericin B in an immunocompromised mouse model, with C. albicans serving as a standard pathogen. The infection's advancement was tracked by evaluating mortality rates, fungal burden, and histopathological alterations.

Results: The C. auris clade V strain exhibited the highest fungal load in heart and kidney tissues on days 3, 5, 7, and 10, with the lowest load observed in brain tissue. In contrast, mice infected with the C. albicans strain showed the highest fungal load in the spleen on days 3, 5, and 10 and in the heart on the 7th day post-infection. Conversely, the average survival time for mice infected with C. auris was 14 days with drug treatment, demonstrating that AMB treatment significantly improved the survival rate of mice infected with C. auris clade V.

Conclusion: This study highlights the differing pathogenic behaviors of C. auris clade V and C. albicans. Although C. albicans exhibits greater virulence in untreated infections, C. auris clade V remains a serious threat, even at lower colony levels. The improved survival rates in infected mice treated with amphotericin B underscore the importance of effective therapeutic interventions. Further research is essential to enhance our understanding of these pathogens and optimize treatment protocols.

Background: Aspergillosis, a fungal disease caused by the genus Aspergillus, can lead to various clinical manifestations, especially in immunocompromised individuals. YouTube serves as a major source of health information, but the quality and reliability of its content vary. We evaluated the quality, reliability, and educational value of uploaded YouTube videos on aspergillosis.

Methods: On August 20th, 2024, YouTube Videos on aspergillosis were selected based on the number of views and analyzed using the Global Quality Score (GQS), Journal of the American Medical Association (JAMA) Benchmark Criteria, and the Modified DISCERN Questionnaire. Videos were categorized by creators (Doctors, Medical tutors, Patients, Others). Descriptive statistics, Mann-Whitney U test, and Spearman correlation were used to assess video quality and its association with video parameters.

Results: We included 50 videos, which generally exhibited high content quality with a median GQS of 4.00 (IQR = 0.50), good information quality with a JAMA median score of 3.00 (IQR = 0.75), and moderate reliability with mDISCERN median score of 3.40 (IQR = 1.00). Significant positive correlations were found between video duration and GQS (r = 0.592, p < 0.001), JAMA (r = 0.308, p = 0.031), and mDISCERN (r = 0.667, p < 0.001). High-quality videos had significantly longer durations, with a median of 12.97 min (IQR = 16.57) compared to low-to-medium-quality videos with 2.00 min (IQR = 5.57) (p < 0.001).

Conclusion: There is a significant variability in the quality of videos on aspergillosis on YouTube. While longer videos tend to offer more reliable and comprehensive information, relying on popularity metrics alone may lead to misinformation. There is a need for critical evaluation of online information on this important fungal disease and the promotion of high-quality content to enhance public understanding and health outcomes.

The incidence of fungal infections has increased significantly in recent years. In addition to infections caused by common clinical fungal pathogens such as Candida spp., Aspergillus spp. and Trichoderma spp., infections with rare opportunistic fungal pathogens are increasing annually. Infections by rare yeasts are particularly intractable due to difficulties in identification, the absence of clinical breakpoints, and lack of clinical treatment options. The purpose of this review is to provide a comprehensive understanding of clinical cases of infection caused by rare yeasts worldwide in the past five years. Specifically, dozens of case reports of infections caused by rare yeasts, including basidiomycetes and ascomycetes, are summarized. Most infections occurred in newborns and older people. These rare yeasts were mostly isolated from the blood, skin, and other common sites of infection, but isolation from the digestive system, urinary system, and other unexpected anatomical sites was also reported. Although traditional antifungal drugs have good therapeutic effects against most of these rare yeast infections, a small proportion of cases were fatal due to unclear pathogen identification or intrinsic resistance.

Fungal bloodstream infection is a severe condition associated with high mortality rates. Major risk factors of fungal bloodstream infection (BSI) include immunosuppression, abdominal surgery and malignancy. The epidemiology and underlying morbidities vary by geographic region and institute. We analyzed the species distribution, antifungal susceptibility, risk factors and mortality of fungal bloodstream infection at our institute over a 14-year period. Four-hundred and fourteen episodes were detected, and the average annual incidence was 0.23/1000 admissions. The most frequent species was Candida albicans (54%), followed by C. glabrata (16%). Abdominal surgery (48.3%), a solid tumor (31.4%), and immunosuppression (26.3%) were identified as major risk factors. Abdominal surgery was more prevalent in patients suffering from BSI caused by C. albicans or C. glabrata. C. tropicalis and C. albicans were associated with increased mortality in patients with neutropenia and/or immunosuppression. Azole prophylaxis in patients suffering from a hematologic malignancy or who recently had undergone organ transplantation increased the risk of C. krusei BSI. Overall 30-day mortality was 45.7% in any fungal BSI. Mortality of C. tropicalis BSI (59.4%) was the highest. Acquired antifungal resistance was not detected during the study period.

Chronic pulmonary aspergillosis (CPA) is a progressive fungal disease that primarily affects individuals with preexisting lung conditions. The clinical presentation, radiological characteristics, and outcomes of CPA in people living with HIV (PLHIV) remain poorly understood. We conducted a retrospective study at Hospital das Clínicas, University of São Paulo, Brazil, reviewing medical records of CPA patients from January 2010 to November 2024. HIV-infected and HIV-negative CPA patients were compared in terms of clinical features, diagnostic findings, treatment strategies, and outcomes. CPA diagnosis was based on European Society for Clinical Microbiology and Infectious Diseases and European Respiratory Society criteria. A total of 96 CPA patients were included, of whom 8 (8%) were PLHIV. Compared to HIV-negative patients, PLHIV were younger (median age: 44 vs. 52 years, p = 0.13) and more likely to have active pulmonary TB (38% vs. 4.5%, p = 0.013). Itraconazole was the most used antifungal in both groups (57% vs. 79%, p = 0.2). One-year mortality also did not differ significantly between PLHIV and HIV-negative patients (13% vs. 4%, p = 0.3). Notably, 50% of PLHIV experienced clinical failure despite prolonged antifungal therapy and/or surgery. In conclusion, CPA in PLHIV is frequently associated with active TB and presents with a high rate of clinical failure despite treatment. Our findings highlight the need for optimized diagnostic and therapeutic strategies for CPA in this under-recognized population. Further prospective studies are warranted to better define prognostic factors and improve management approaches.

We analyzed mucormycosis data from the Zygomyco.net registry (2009-2022), encompassing cases from 16 countries. India, Russia and the Czech Republic provided the largest contributions. India reported the highest case number, consistent with its substantially higher incidence compared to that of high-income countries. Among the 382 patients with mucormycosis, 236 (61.8%) were male (male-to-female ratio 1.6). The median age was 48 years [interquartile range (IQR) 32-60]. There were 59 pediatric patients (median age ranging from < 1 month to 19 years). Diabetes mellitus type 2 was the most common underlying condition (39%), with significant geographic variation (> 70% of cases in India and Iran but only 6.9% in Europe). Hematologic malignancies (HM, 31.4%), the second most common underlying condition, were absent in India and Iran. The primary clinical presentations were rhino-orbito-cerebral mucormycosis (ROCM, 36.6%), pulmonary (33.2%) and cutaneous mucormycosis (17.5%). Patients with diabetes mellitus typically developed ROCM (55.9%), while pulmonary infections were more common in those with HM or hematopoietic cell transplantation (HCT) (47.5%, p < 0.001). Rhizopus was the leading fungal genus (58%), followed by Lichtheimia (13.7%) and Mucor (7%), with regional variations. Pulmonary infections in HM patients were linked to L. corymbifera and R. microsporus, while Apophysomyces spp. and Saksenaea spp. were more frequent in Indian healthcare-associated cutaneous cases. Concomitant infections were observed in 8.7% of patients with HM, complicating diagnosis and treatment. In most of them (57.1%), Aspergillus spp. was involved. Improved diagnostic practices, including direct microscopy and cultures, showed higher positivity rates, although PCR remained underutilized. Antifungal therapy, primarily with an amphotericin B formulation, combined with surgery, was the most common therapeutic approach. Overall mortality was high (47.8%), particularly in disseminated or advanced ROCM cases. Multivariable analysis identified older age, advanced ROCM, and HM/HCT as independent mortality risk factors (p < 0.05); whereas localized sinusitis and combined medical and surgical therapy were independently associated with improved outcomes (p < 0.006). This study underscores regional disparities in the mucormycosis epidemiology and species distribution. Improved early detection is needed, particularly in immunocompromised populations with HM. Enhanced surveillance and tailored public health strategies are crucial to address this ongoing global health threat.

Paracoccidioidomycosis is an important deep mycosis in Latin American countries. Its causative agents have been reclassified into five distinct species based on genetic differences: Paracoccidioides brasiliensis sensu stricto, Paracoccidioides americana, Paracoccidioides restrepiensis, Paracoccidioides venezuelensis and Paracoccidioides lutzii. In this study, we propose a new method, based on a nested PCR for partial alpha-tubulin gene amplification, as a tool for diagnosis and species differentiation directly from biological samples. The method could amplify the DNA of the five cultivable Paracoccidioides spp. without amplifying DNA from other fungal species such as Mucor fragilis, Histoplasma capsulatum, Aspergillus fumigatus, Candida albicans, Sporothrix brasiliensis, and Cryptococcus neoformans. The nested PCR detected Paracoccidioides spp. from fresh and formalin-fixed and paraffin-embedded (FFPE) tissues of experimentally infected animals. Amplicons obtained from fresh tissues were successfully used in traditional downstream methods, such as RFLP, for Paracoccidioides spp. identification.However, amplicons from FFPE tissues exhibited several artifacts induced by formalin, which interfered with the RFLP results. DNA sequencing of these nested PCR products revealed G > T/T > G, A > T/T > A, T > C/C > T, and G > A/A > G base changes, affecting the sequence targets for enzymatic digestion.