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

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

Arthroderma is the most diverse genus of dermatophytes, and its natural reservoir is considered to be soil enriched by keratin sources. During a study on the diversity of dermatophytes in wild small rodents in the Czech Republic, we isolated several strains of Arthroderma. To explore the diversity and ecological significance of these isolates from rodents (n = 29), we characterised the strains genetically (i.e., sequenced ITS, tubb and tef1α), morphologically, physiologically, and by conducting mating experiments. We then compared the rodent-derived strains to existing ITS sequence data from GenBank and the GlobalFungi Database to further investigate biogeography and the association of Arthroderma species with different types of environments. In total, eight Arthroderma species were isolated from rodents, including four previously described species (A. crocatum, A. cuniculi, A. curreyi, A. quadrifidum) and four new species proposed herein, i.e., A. rodenticum, A. simile, A. zoogenum and A. psychrophilum. The geographical distribution of these newly described species was not restricted to the Czech Republic nor rodents. Additional isolates were obtained from bats and other mammals, reptiles, and soil from Europe, North America, and Asia. Data mining showed that the genus has a diverse ecology, with some lineages occurring relatively frequently in soil, whereas others appeared to be more closely associated with live animals, as we observed in A. rodenticum. Low numbers of sequence reads ascribed to Arthroderma in soil show that the genus is rare in this environment, which supports the hypothesis that Arthroderma spp. are not soil generalists but rather strongly associated with animals and keratin debris. This is the first study to utilise existing metabarcoding data to assess biogeographical, ecological, and diversity patterns in dermatophytes. Citation: Moulíková Š, Kolařík M, Lorch JM, et al. 2022. Wild rodents harbour high diversity of Arthroderma. Persoonia 50: 27- 47. https://doi.org/10.3767/persoonia.2023.50.02.

• Klíčová slova
• Arthroderma, GlobalFungi, geophilic dermatophytes, mating type genes, new taxa, polyphasic taxonomy, wild rodents,
• Publikační typ
• časopisecké články MeSH

This study looked for correlations between molecular identification, clinical manifestation, and morphology for Trichophyton interdigitale and Trichophyton mentagrophytes. For this purpose, a total of 110 isolates were obtained from Czech patients with various clinical manifestations of dermatophytosis. Phenotypic characters were analyzed, and the strains were characterized using multilocus sequence typing. Among the 12 measured/scored phenotypic features, statistically significant differences were found only in growth rates at 37 °C and in the production of spiral hyphae, but none of these features is diagnostic. Correlations were found between T. interdigitale and higher age of patients and between clinical manifestations such as tinea pedis or onychomychosis. The MLST approach showed that internal transcribed spacer (ITS) genotyping of T. mentagrophytes isolates has limited practical benefits because of extensive gene flow between sublineages. Based on our results and previous studies, there are few taxonomic arguments for preserving both species names. The species show a lack of monophyly and unique morphology. On the other hand, some genotypes are associated with predominant clinical manifestations and sources of infections, which keep those names alive. This practice is questionable because the use of both names confuses identification, leading to difficulty in comparing epidemiological studies. The current identification method using ITS genotyping is ambiguous for some isolates and is not user-friendly. Additionally, identification tools such as matrix-assisted laser desorption/ionization time-of-flight mass spectrometry fail to distinguish these species. To avoid further confusion and to simplify identification in practice, we recommend using the name T. mentagrophytes for the entire complex. When clear differentiation of populations corresponding to T. interdigitale and Trichophyton indotineae is possible based on molecular data, we recommend optionally using a variety rank: T. mentagrophytes var. interdigitale and T. mentagrophytes var. indotineae.

Species in the T. mentagrophytes complex lack support from usual taxonomic methods and simple identification tools are missing or inaccurate. To avoid recurring confusions, we propose naming the entire complex as T. mentagrophytes and optionally use rank variety to classify the observed variability.

• Klíčová slova
• anthropophilic dermatophytes, dermatophytosis, multigene phylogeny, skin infections, zoophilic dermatophytes,
• MeSH
• Arthrodermataceae MeSH
• DNA fungální genetika   chemie   MeSH
• fenotyp MeSH
• fylogeneze MeSH
• mezerníky ribozomální DNA genetika   chemie   MeSH
• multilokusová sekvenční typizace veterinární   MeSH
• sekvenční analýza DNA veterinární   MeSH
• tinea * diagnóza   veterinární   MeSH
• Trichophyton MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• DNA fungální MeSH
• mezerníky ribozomální DNA MeSH

Trichophyton benhamiae var. luteum and T. europaeum - recently described dermatophytes within the T. benhamiae complex - were identified in nine cases of dermatophytosis involving guinea pigs, chinchillas and dogs. The diagnosis was obtained through direct hair/scale examination, culture and sequencing of the internal transcribed spacer region of ribosomal DNA.

Trichophyton benhamiae var. luteum et T. europaeum - dermatophytes récemment décrits au sein du complexe T. benhamiae - ont été identifiés dans neuf cas de dermatophytose de cobayes, de chinchillas et de chiens. Le diagnostic a été obtenu par examen direct des poils/écailles, culture et séquençage de la région ITS de l'ADN ribosomique.

• MeSH
• Arthrodermataceae * genetika   MeSH
• morčata MeSH
• nemoci psů * diagnóza   MeSH
• psi MeSH
• ribozomální DNA MeSH
• tinea * diagnóza   veterinární   MeSH
• Trichophyton genetika   MeSH
• zvířata MeSH
• Check Tag
• morčata MeSH
• psi MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• Názvy látek
• ribozomální DNA MeSH

Trichophyton erinacei is a main cause of dermatophytosis in hedgehogs and is increasingly reported from human infections worldwide. This pathogen was originally described in the European hedgehog (Erinaceus europaeus) but is also frequently found in the African four-toed hedgehog (Atelerix albiventris), a popular pet animal worldwide. Little is known about the taxonomy and population genetics of this pathogen despite its increasing importance in clinical practice. Notably, whether there are different populations or even cryptic species associated with different hosts or geographic regions is not known. To answer these questions, we collected 161 isolates, performed phylogenetic and population-genetic analyses, determined mating-type, and characterised morphology and physiology. Multigene phylogeny and microsatellite analysis supported T. erinacei as a monophyletic species, in contrast to highly incongruent single-gene phylogenies. Two main subpopulations, one specific mainly to Atelerix and second to Erinaceus hosts, were identified inside T. erinacei, and slight differences in the size of microconidia and antifungal susceptibilities were observed among them. Although the process of speciation into two lineages is ongoing in T. erinacei, there is still gene flow between these populations. Thus, we present T. erinacei as a single species, with notable intraspecies variability in genotype and phenotype. The data from wild hedgehogs indicated that sexual reproduction in T. erinacei and de novo infection of hedgehogs from soil are probably rare events and that clonal horizontal spread strongly dominates. The molecular typing approach used in this study represents a suitable tool for further epidemiological surveillance of this emerging pathogen in both animals and humans. The results of this study also highlighted the need to use a multigene phylogeny ideally in combination with other independent molecular markers to understand the species boundaries of dermatophytes. Citation: Čmoková A, Kolařík M, Guillot J, et al. 2022. Host-driven subspeciation in the hedgehog fungus, Trichophyton erinacei, an emerging cause of human dermatophytosis. Persoonia 48: 203-218. https://doi.org/10.3767/persoonia.2022.48.06.

• Klíčová slova
• Trichophyton benhamiae complex, epizootic fungal infections, microsatellite typing, multigene phylogeny, population genetics, skin infections, zoophilic dermatophytes,
• Publikační typ
• časopisecké články MeSH

Microsporum canis is considered one of the most common zoophilic dermatophyte species causing infections in animals and humans worldwide. However, molecular epidemiological studies on this dermatophyte are still rare. In this study, we aimed to analyse the population structure and relationships between M. canis strains (n = 66) collected in southern Italy and those isolated from symptomatic and asymptomatic animals (cats, dogs and rabbits) and humans. For subtyping purposes, using multilocus sequence typing (MLST) and multilocus microsatellite typing (MLMT), we first used a limited set of strains to screen for variability. No intraspecies variability was detected in six out of the eight reference genes tested and only the ITS and IGS regions showed two and three sequence genotypes, respectively, resulting in five MLST genotypes. All of eight genes were, however, useful for discrimination among M. canis, M. audouinii and M. ferrugineum. In total, eighteen microsatellite genotypes (A-R) were recognized using MLMT based on six loci, allowing a subdivision of strains into two clusters based on the Bayesian iterative algorithm. Six MLMT genotypes were from multiple host species, while 12 genotypes were found only in one host. There were no statistically significant differences between clusters in terms of host spectrum and the presence or absence of lesions. Our results confirmed that the MLST approach is not useful for detailed subtyping and examining the population structure of M. canis, while microsatellite analysis is a powerful tool for conducting surveillance studies and gaining insight into the epidemiology of infections due to this pathogen.

• Klíčová slova
• genetic diversity, microsatellite typing, multilocus sequence typing, population structure, zoonotic infections, zoophilic dermatophytes,
• Publikační typ
• časopisecké články MeSH

Trichophyton quinckeanum, a zoophilic dermatophyte mostly known as the causative agent of rodent favus, is relatively rarely reported to cause human infections. Indeed, no infections were detected in Czechia between 2012 and 2015 despite routine verification of species identification by ITS rDNA sequencing. By contrast, 25 human and 11 animal cases of infection were documented from December 2016 to December 2020 and the rates tended to grow every following year. Interestingly, most of the cases were reported in the Olomouc region, suggesting a local outbreak. We bring the evidence that human T. quinckeanum infections are most commonly contracted from infected cats or, less frequently, dogs. Although rodents or contaminated soil and environment could be the source of infection to cats and dogs, the occurrence of infections in multiple animals in the same household suggests direct transmission among animals. Confirmation of the identification by molecular methods is highly recommended due to morphological similarity with T. mentagrophytes/T. interdigitale. Antifungal susceptibility testing of isolates to eight antifungals was performed using EUCAST methodology (E.Def 11.0). Among the tested antifungals, terbinafine, amorolfine, ciclopirox and efinaconazole were most potent in vitro and elevated minimum inhibitory concentrations were obtained for fluconazole and ketoconazole.

• Klíčová slova
• EUCAST, MALDI-TOF mass spectrometry, antifungal susceptibility testing, terbinafine, tinea capitis, tinea corporis, zoonotic infections, zoophilic dermatophytes,
• Publikační typ
• časopisecké články MeSH