BACKGROUND: The Trichophyton mentagrophytes complex encompasses common dermatophytes causing superficial mycoses in humans and animals. The taxonomy of the complex is unstable, with conflicting views on the species status of some taxa, particularly T. indotineae and T. interdigitale. Due to the presence of intermediate genotypes, neither MALDI-TOF MS nor ITS rDNA sequencing can accurately distinguish all taxa in the complex, potentially contributing to clinical misdiagnoses. OBJECTIVES: This research resolves phylogenetic relationships within the T. mentagrophytes complex. Based on these data, the taxonomical recommendations are suggested. METHODS: In order to resolve the phylogenetic relationship of the T. mentagrophytes complex, we employed Restriction Site-Associated DNA Sequencing (RADseq) to produce a high-resolution single nucleotide polymorphism (SNP) dataset from 95 isolates. The SNP-based analyses indicated the presence of two major genetic clusters corresponding to T. mentagrophytes (including T. indotineae) and T. interdigitale. RESULTS: Our results challenge the species status of T. indotineae because of insufficient genetic divergence from T. mentagrophytes. Therefore, we propose designating T. indotineae as T. mentagrophytes var. indotineae (or T. mentagrophytes ITS genotype VIII) to avoid further splitting of the complex and taxonomic inflation. Although T. interdigitale shows clearer genetic differentiation, its separation is incomplete and identification of some isolates is ambiguous when using routine methods, leading us to consider it a variety as well: T. mentagrophytes var. interdigitale. CONCLUSIONS: We recommend using T. mentagrophytes as the overarching species name for all complex isolates. Where precise molecular identification is possible, the use of variety ranks is encouraged. Since identical resistance mechanisms are not specific to any genotype or dermatophyte species, identifying antifungal resistance is more important than differentiating closely related genotypes or populations.

• Klíčová slova
• Trichophyton interdigitale, Trichophyton mentagrophytes, anthropophilic dermatophytes, antifungal resistance, dermatophytosis, population structure, taxonomy, zoophilic dermatophytes,
• MeSH
• antifungální látky * farmakologie   MeSH
• Arthrodermataceae * genetika   klasifikace   účinky léků   MeSH
• DNA fungální genetika   MeSH
• fylogeneze * MeSH
• genomika metody   MeSH
• genotyp MeSH
• jednonukleotidový polymorfismus MeSH
• lidé MeSH
• sekvenční analýza DNA MeSH
• tinea mikrobiologie   MeSH
• Trichophyton * genetika   klasifikace   účinky léků   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antifungální látky * MeSH
• DNA fungální MeSH

BACKGROUND: Trichophyton mentagrophytes ITS genotype VII (TMVII) has recently been identified in France as the causative agent of dermatophyte infections transmitted during sexual activity among men who have sex with men (MSM). OBJECTIVES: Our objective was to provide new insights into the epidemiology, clinical presentation and treatment of TMVII infections based on cases diagnosed from October 2022 to September 2023 in three medical mycology laboratories in Paris. Additionally, we aimed to perform molecular characterization of TMVII strains collected in Paris, as well as in Switzerland. METHODS: We identified all isolates from skin and hair belonging to the T. mentagrophytes complex by sequencing the ITS region. For isolates corresponding to TMVII, clinical data were retrieved from medical records. For all available TMVII strains that we isolated since January 2021, we sequenced tef1α and tubb and determined the MAT locus idiomorph. RESULTS: We identified 32 cases of TMVII Infections. All cases occurred in men, 30 of whom reported having sex with men. Fifteen cases were sporadic cases including four among sex workers. The other 17 cases belonged to a single cluster involving a tantric masseur who infected 15 clients and his roommate. The median time from massage to lesion onset was 16 [2-52] days. Except for one patient, all other patients received systemic antifungal treatment with terbinafine. We observed five patients whose cultures remained positive even after 3-4 weeks of treatment and five patients experienced a relapse of the infection after discontinuing antifungal treatment. All French isolates exhibited identical tef1α and tubb sequences, as well as the same MAT idiomorph locus. They displayed variations in the tef1α sequence compared to isolates from Switzerland and the Czech Republic. CONCLUSIONS: We confirm the active circulation of TMVII among MSM in France, which is associated with challenges in diagnosis, treatment and prevention.

• MeSH
• antifungální látky terapeutické užití   MeSH
• Arthrodermataceae * genetika   MeSH
• dospělí MeSH
• genotyp MeSH
• homosexualita mužská * MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• tinea * epidemiologie   farmakoterapie   mikrobiologie   MeSH
• Trichophyton * genetika   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Francie epidemiologie   MeSH
• Názvy látek
• antifungální látky MeSH

The clinical diagnosis of dermatophytosis and identification of dermatophytes face challenges due to reliance on culture-based methods. Rapid, cost-effective detection techniques for volatile organic compounds (VOCs) have been developed for other microorganisms, but their application to dermatophytes is limited. This study explores using VOCs as diagnostic markers for dermatophytes. We compared VOC profiles across different dermatophyte taxa using solid-phase microextraction (SPME) and advanced analytical methods: gas chromatography-mass spectrometry (GC-MS) and comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (GC×GC-TOFMS). We analyzed 47 dermatophyte strains from 15 taxa grown on sheep wool, including clinically significant species. Additionally, we examined phylogenetic relationships among the strains to correlate genetic relatedness with metabolite production. Our results showed that GC×GC-TOFMS offered superior resolution but similar differentiation of VOC profiles compared to GC-MS. VOC spectra allowed reliable distinction of taxonomic units at the species level and below, however, these distinctions showed only a slight correlation with phylogenetic data. We identified pan-dermatophyte and species- or strain-specific VOC profiles, indicating their potential for rapid, non-invasive detection of dermatophyte infections, including epidemic strains. These patterns could enable future taxa-specific identification. Our study highlights the potential of VOCs as tools for dermatophyte taxonomy and diagnosis.

• Klíčová slova
• Dermatophytes, Gas chromatography-mass spectrometry, Metabolite profiles, Volatile organic compounds,
• MeSH
• Arthrodermataceae * klasifikace   izolace a purifikace   genetika   MeSH
• fylogeneze * MeSH
• lidé MeSH
• mikroextrakce na pevné fázi MeSH
• odoranty analýza   MeSH
• ovce MeSH
• plynová chromatografie s hmotnostně spektrometrickou detekcí * MeSH
• těkavé organické sloučeniny * analýza   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• těkavé organické sloučeniny * MeSH