RESUMO
Arthroderma is the most diverse genus among dermatophytes encompassing species occurring in soil, caves, animal burrows, clinical material and other environments. In this study, we collected ex-type, reference and authentic strains of all currently accepted Arthroderma species and generated sequences of three highly variable loci (ITS rDNA, ß-tubulin, and translation elongation factor 1-α). The number of accepted species was expanded to 27. One novel species, A. melbournense (ex-type strain CCF 6162T = CBS 145858T), is described. This species was isolated from toenail dust collected by a podiatrist in Melbourne, during an epidemiological study of four geographical regions of Eastern Australia. Trichophyton terrestre, Chrysosporium magnisporum, and Chrysosporium oceanitis are transferred to Arthroderma. Typification is provided for T. terrestre that is not conspecific with any of the supposed biological species from the former T. terrestre complex, that is, A. insingulare, A. lenticulare and A. quadrifidum. A multi-gene phylogeny and reference sequences provided in this study should serve as a basis for future phylogenetic studies and facilitate species identification in practice. LAY ABSTRACT: The genus Arthroderma encompasses geophilic dermatophyte species that infrequently cause human and animal superficial infections. Reference sequences from three genetic loci were generated for all currently accepted Arthroderma species and phylogeny was constructed. Several taxonomic novelties are introduced. The newly provided data will facilitate species identification and future taxonomic studies.
Assuntos
Arthrodermataceae/classificação , Arthrodermataceae/genética , DNA Fúngico/genética , Genes Fúngicos/genética , Filogenia , Austrália , DNA Espaçador Ribossômico/genética , Humanos , Microsporum/classificação , Microsporum/genética , Fator 1 de Elongação de Peptídeos/genética , Trichophyton/classificação , Trichophyton/genética , Tubulina (Proteína)/genéticaRESUMO
BACKGROUND: Dermatophytosis is one of the most frequent superficial mycoses in the world. MAIN AIM: To describe the cases of skin dermatophytosis and its main aetiologic agents in patients referred to a Mycological Reference Laboratory in Medellín, Colombia. METHODS: A retrospective study was carried out with records of patients referred between 1994 and 2016 to the Corporación para Investigaciones Biológicas (CIB), Medellín-Colombia, because of clinical suspicion of skin dermatophytosis. RESULTS: Of a total of 5628 clinical records of patients with suspicion of skin dermatophytosis analysed, 2780 (49.4%) had a proven or probable dermatophytosis diagnosis, 2774 cultures were performed, and aetiologic agents were isolated in 2576 samples (92.9%). The most frequently isolated aetiologic agents were Trichophyton rubrum (44.3%), followed by Trichophyton mentagrophytes complex (33.3%), Epidermophyton floccosum (12.4%), Nannizzia gypseum complex (5.7%, formerly Microsporum gypseum), Microsporum canis (3.5%) and Trichophyton tonsurans (0.8%). The most frequent clinical forms were tinea pedis (72.7%) and tinea corporis (12.7%). In addition, a group of patients (0.9%) developed mixed infections by two dermatophyte agents and another (4.1%) developed infections in more than one anatomical site. CONCLUSIONS: The results of the present study are coherent with previous reports where T rubrum and T mentagrophytes complex were the main causative agents of dermatophytosis. However, the increased incidence of N gypsea complex over M canis is worth highlighting.
Assuntos
Dermatomicoses/epidemiologia , Fungos/isolamento & purificação , Tinha/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Arthrodermataceae/classificação , Arthrodermataceae/isolamento & purificação , Criança , Pré-Escolar , Colômbia/epidemiologia , Dermatomicoses/microbiologia , Epidermophyton/classificação , Epidermophyton/isolamento & purificação , Fungos/classificação , Humanos , Lactente , Masculino , Microsporum/classificação , Microsporum/isolamento & purificação , Pessoa de Meia-Idade , Estudos Retrospectivos , Pele/microbiologia , Pele/patologia , Tinha/epidemiologia , Trichophyton/classificação , Trichophyton/isolamento & purificação , Adulto JovemRESUMO
Phylogenetic studies of the family Arthrodermataceae have revealed seven monophyletic dermatophyte clades representing the genera Trichophyton, Epidermophyton, Nannizzia, Lophophyton, Paraphyton, Microsporum, and Arthroderma. Members of the genus Nannizzia are geo- or zoophiles that occasionally infect humans. With the newly proposed taxonomy, the genus Nannizzia comprises thirteen species, i.e., Nannizzia aenigmatica, N. corniculata, N. duboisii, N. fulva, N. graeserae, N. gypsea, N. nana, N. incurvata, N. perplicata, N. persicolor, N. praecox, and two novel species. Nannizzia polymorpha sp. nov. was isolated from a skin lesion of a patient from French Guiana. For the strain originally described as Microsporum racemosum by Borelli in 1965, we proposed Nannizzia lorica nom. nov. The species are fully characterized with five sequenced loci (ITS, LSU, TUB2, RP 60S L1 and TEF3), combined with morphology of the asexual form and physiological features. A key to the species based on phenotypic and physiological characters is provided.
Assuntos
Arthrodermataceae/genética , Arthrodermataceae/classificação , Epidermophyton/classificação , Epidermophyton/genética , Microsporum/classificação , Microsporum/genética , Filogenia , Trichophyton/classificação , Trichophyton/genéticaRESUMO
Recent taxonomical revisions based on multilocus gene sequencing have provided some clarifications to dermatophyte (Arthrodermataceae) family tree. These changes promoted us to investigate the impact of the changed nomenclature of the dermatophyte strains in the BCCM/IHEM fungal collection, which contains strains of all dermatophyte genera except for Ctenomyces. For 688 strains from this collection, both internal transcribed spacer region (ITS) and partial ß-tubulin (BT) sequences were aligned and a multilocus phylogenetic tree was constructed. The ITS + BT phylogentic tree was able to distinguish the genera Arthroderma, Lophophyton, Microsporum, Paraphyton, Nannizzia and Trichophyton with high certainty. Epidermophyton, which is widely considered as a well-defined genus with E. floccosum as the only representative, fell within the Nannizzia clade, whereas the phylogenetic analysis, based on the ITS region alone, differentiates Epidermophyton from Nannizzia as a separate genus. Re-identification and reclassification of many strains in the collection have had a profound impact on the composition of the BCCM/IHEM dermatophyte collection. The biggest change is the decline of prevalence of Arthroderma strains; starting with 103 strains, only 22 strains remain in the genus after reassessment. Most Arthroderma strains were reclassified into Trichophyton, with A. benhamiae and A. vanbreuseghemii leaving the genus. The amount of Microsporum strains also dropped significantly with most of these strains being reclassified into the genera Paraphyton and Nannizzia.
Assuntos
Arthrodermataceae/genética , Arthrodermataceae/classificação , Epidermophyton/classificação , Epidermophyton/genética , Microsporum/classificação , Microsporum/genética , Filogenia , Tubulina (Proteína)/genéticaRESUMO
Three boys from the same city, treated by the same dermatologist, developed tinea capitis. Two of them, 4 and 8 years old, underwent mycological diagnostic workup. However, no pathogens familiar in this country, such as Microsporum (M.) canis or Trichophyton (T.) tonsurans, were isolated, but instead that of a dermatophyte that has not been found in Germany for decades. Both dermatophyte isolates showed white-beige-brownish colonies with a flat, radiating edge and a central, verrucous curvature. The sequencing of the internal transcribed spacer (ITS) region of the rDNA confirmed the suspicion of M. ferrugineum already expressed based on the morphological picture. The anthropophilic dermatophyte occurs in the Middle East, Asia, Eastern Europe and Africa and is considered to be the cause of tinea capitis or tinea corporis in children and adolescents. In 2016, M. ferrugineum has again been isolated in Germany, probably as a result of migration movements. The fungus is strikingly isolated to martial arts, especially wrestlers. It mainly affects children and adolescents, some with a Russian-German background. The anthropophilic dermatophyte is transmitted directly from person to person, especially in the case of tinea capitis. An indirect transmission, for example, via mats in martial arts is likely.
Assuntos
Microsporum/isolamento & purificação , Tinha do Couro Cabeludo/diagnóstico , Antifúngicos/uso terapêutico , Arthrodermataceae , Criança , Pré-Escolar , Alemanha , Humanos , Masculino , Microsporum/classificação , Tinha do Couro Cabeludo/tratamento farmacológico , Resultado do TratamentoRESUMO
In this study, a novel real-time polymerase chain reaction (PCR) assay (DermaGenius®2.0, PathoNostics BV, Maastricht, The Netherlands) and a recently developed microarray test (EUROArray Dermatomycosis, Euroimmun, Lübeck, Germany) were evaluated regarding their diagnostic specificity to identify dermatophyte DNA. The tests were compared to conventional methods and sequencing. The microarray Dermatomycosis test allows the detection of 50 dermatophytes and definitive identification of 23 dermatophyte species, 6 yeasts and moulds combined in one test. In comparison, real-time PCR is able to identify 11 dermatophytes and one yeast at the species level. Using the EUROArray, 22 out of 24 dermatophyte species were correctly identified. Using real-time PCR, 9 out of the 11 different dermatophytes included in the test kit were correctly identified. Both molecular tests for detection and differentiation of dermatophytes are useful tools for daily clinical practice. The real-time PCR test does not detect as many species, and specificity is slightly lower. However, real-time PCR is a very fast and easy to perform test, especially since no post-PCR step is necessary. Real-time PCR detects the most frequent dermatophytes like T. rubrum, T. interdigitale, and M. canis without any problems. The EUROArray is more elaborate to perform in the lab, due to the hybridization step. However, the EUROArray shows higher specificity and can detect a much broader range of causative agents, including rare species, in dermatomycology.
Assuntos
DNA Fúngico/classificação , DNA Fúngico/genética , Dermatomicoses , Reação em Cadeia da Polimerase em Tempo Real/métodos , Trichophyton/classificação , Trichophyton/genética , DNA Fúngico/isolamento & purificação , Alemanha , Humanos , Microsporum/classificação , Microsporum/genética , Microsporum/isolamento & purificação , Países Baixos , Trichophyton/isolamento & purificaçãoRESUMO
In a preschool a long-lasting outbreak of Trichophyton (T.) tonsurans tinea capitis was stopped by a concurrent screening of all persons at-risk (Nâ¯= 264) with the hairbrush technique and a therapy based on clinical picture as well as on the quantitative results of the culture. In addition to the 5 symptomatic patients 10 asymptomatic carriers undetected until now were especially important as vectors. With the rising incidence of T. tonsurans and T. violaceum and the return of Microsporum (M.) audouinii in central Europe such outbreaks are likely to occur more frequently. According to the literature an early and comprehensive screening of the entire at-risk population, a combined antimycotic therapy of the symptomatic and at least a topical therapy of the asymptomatic as well as measures of decontamination are important conditions for successful outbreak management. In our hands the hairbrush technique is a reliable, painless and easy-to-perform screening method which also allows a quantification of fungal load.
Assuntos
Surtos de Doenças , Microsporum/isolamento & purificação , Tinha do Couro Cabeludo/diagnóstico , Tinha do Couro Cabeludo/microbiologia , Trichophyton/isolamento & purificação , Pré-Escolar , Europa (Continente) , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Microsporum/classificação , Tinha do Couro Cabeludo/epidemiologia , Trichophyton/classificaçãoRESUMO
Dermatophytes are keratinophilic fungi belonging to the family Arthrodermataceae. Despite having a monophyletic origin, its systematics has always been complex and controversial. Sequencing of nuclear ribosomal ITS and D1/D2 rDNA has been proposed as an efficient tool for identifying species in this group of fungi, while multilocus analyses have been used for phylogenetic species recognition. However, the search for new markers, with sequence and size variation, which enable species identification in only one polymerase chain reaction (PCR) step, is very attractive. Inteins seems to fulfill these characteristics. They are self-splicing genetic elements present within housekeeping coding genes, such as PRP8, that codify the most important protein of the spliceosome. The PRP8 intein has been described for Microsporum canis in databases but has not been studied in dermatophytes in any other published work. Thus, our aim was to determine the potential of this intervening element for establishing phylogenetic relationships among dermatophytes and for identifying species. It was found that all studied species have a full-length PRP8 intein with a Homing Endonuclease belonging to the family LAGLIDADG. Phylogenetic analyses were consistent with other previous phylogenies, confirming Epidermophyton floccosum in the same clade of the Arthroderma gypseum complex, Microsporum audouinii close to M. canis, differentiating A. gypseum from Arthroderma incurvatum, and in addition, better defining the Trichophyton interdigitale and Trichophyton rubrum species grouping. Length polymorphism in the HE region enables identification of the most relevant Microsporum species by a simple PCR-electrophoresis assay. Intein PRP8 within dermatophytes is a powerful additional tool for identifying and systematizing dermatophytes.
Assuntos
Evolução Molecular , Proteínas Fúngicas/genética , Fungos/classificação , Fungos/genética , Inteínas/genética , Filogenia , Arthrodermataceae/classificação , Arthrodermataceae/genética , Sequência de Bases , DNA Fúngico/genética , Endonucleases/genética , Epidermophyton/classificação , Epidermophyton/genética , Fungos/enzimologia , Humanos , Microsporum/classificação , Microsporum/genética , Reação em Cadeia da Polimerase , Polimorfismo Genético , Especificidade da Espécie , Trichophyton/classificação , Trichophyton/genéticaRESUMO
Microsporum canis is a zoophilic dermatophyte, which is very contagious, especially to cats and dogs. Asymptomatic animal carriers of M. canis are regarded a critical factor in the epidemiology of the disease. The aim of this study was to investigate the epidemiological origin of M. canis isolates using morphological traits in combination with molecular analysis. Identification of dermatophyte strains was carried out by correlating the clinical manifestation of the infection with a micro- and macroscopic examination. To confirm the species affiliation fully, molecular differentiation methods were used. A positive result of the culture examination was obtained from the samples with arthrospores in the direct analysis, that is, from a symptomatic cat and humans, and from a cat without any signs of infection. The microsatellite-primed PCR fingerprinting (MSP-PCR) electro-profiles were identical for all analysed strains. The melting profile-PCR (MP-PCR) electrophoregram indicated variability of the genomes of the strains. The search for the source of the infection indicated one cat that did not have any signs of dermatophytosis. PCR-fingerprinting techniques are useful tools for epidemiological investigation of the origin of dermatophyte infection. These methods can also be used in many cases for species identification of dermatophytes and clarification of the relationships among varieties of a species.
Assuntos
Doenças do Gato/epidemiologia , Laboratórios , Microsporum/isolamento & purificação , Tinha/epidemiologia , Tinha/veterinária , Zoonoses/epidemiologia , Adulto , Animais , Doenças do Gato/microbiologia , Doenças do Gato/patologia , Gatos , Impressões Digitais de DNA , Feminino , Variação Genética , Humanos , Técnicas Microbiológicas , Repetições de Microssatélites , Microscopia , Microsporum/classificação , Microsporum/genética , Microsporum/crescimento & desenvolvimento , Pessoa de Meia-Idade , Epidemiologia Molecular , Tipagem Molecular , Técnicas de Tipagem Micológica , Tinha/microbiologia , Tinha/patologia , Zoonoses/microbiologia , Zoonoses/patologiaRESUMO
Matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS) is becoming a popular technology in clinical microbiology. It is a fast and highly specific method for the routine identification of micro-organisms. In this study, we evaluated the suitability of dermatophyte identification after only 2 days of colony growth using MALDI-TOF MS. Two protein extraction protocols were also evaluated consisting of either formic acid alone or of ethanol-formic acid-acetonitrile to achieve a complete protein extraction. Morphology-based techniques were used as the diagnostic standard methods and MALDI-TOF MS results were obtained using the manufacturer's spectral library. Using the formic acid protein extraction protocol after 2 days of colony growth, 70 and 46% of dermatophytes were properly identified at the genus and species-level respectively. The addition of ethanol-formic acid-acetonitrile extraction protocol increased the identification to 90 and 62%. Based on our observations, we propose a two-step workflow for the fast and reliable identification of dermatophytes after only 2 days of colony growth. This flow chart consists of a first direct deposition procedure with the addition of formic acid, followed by a complete protein extraction when dermatophyte identification is not successful. SIGNIFICANCE AND IMPACT OF THE STUDY: In this study, a two-step workflow for the identification of clinical dermatophytes using MALDI-TOF analysis and commercially available spectral library was developed. The workflow consists of an initial direct deposition of the sample on the MALDI plate and formic acid protein extraction at 2 days of growth culture; if dermatophyte identification is not successful, a complete protein extraction using ethanol-formic acid-acetonitrile is subsequently performed. Using this workflow, the correct isolate identifications increase up to 90%; of these, 27% are identified at the genus-level, providing sufficient information to start an antifungal treatment. The method here proposed represents a fast and useful approach to differentiate dermatophytes grown in culture.
Assuntos
Arthrodermataceae/classificação , Epidermophyton/classificação , Microsporum/classificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Trichophyton/classificação , Acetonitrilas/química , Dermatomicoses/microbiologia , Etanol/química , Formiatos/química , Humanos , Extração Líquido-Líquido/métodos , Técnicas de Tipagem Micológica/métodos , Fluxo de TrabalhoRESUMO
Tinea capitis is a dermatophyte infection common among prepubertal children in sub-Saharan Africa and mainly caused by Trichophyton and Microsporum species. Accurate identification is challenging as conventional methods like culture and microscopy are slow and mostly based on morphological characteristics, which make them less sensitive and specific. Modern molecular methods, like polymerase chain reaction (PCR) assays, are gaining acceptance and are quick as well as accurate. The aim of this study was to investigate the clinical patterns of tinea capitis and to accurately identify the most common causative dermatophytes affecting the scalps of children aged 1 to 16 years attending the Skin Clinic at Mbarara University of Science and Technology (MUST), Mbarara, Uganda, East Africa, using both conventional mycological methods and PCR-ELISA for detection of dermatophyte DNA. One hundred fifteen clinical samples from children from Western Uganda attending the MUST Skin Clinic with a clinical diagnosis of tinea capitis were analyzed. T. violaceum was identified as the most common causative agent, followed by M. audouinii, T. soudanense, and T. rubrum. The early identification of the causative agent of tinea capitis is a prerequisite for the effective management of the disease, the identification of probable source and the prevention of spreading. Children with tinea capitis in Western Uganda should be treated by systemic therapy rather than topical preparations to ensure high cure rates as the most common causative dermatophytes T. violaceum exhibits an endothrix rather than ectothrix invasion of the hair follicle.
Assuntos
Ensaio de Imunoadsorção Enzimática , Microsporum/classificação , Microsporum/genética , Técnicas de Tipagem Micológica/métodos , Reação em Cadeia da Polimerase , Tinha do Couro Cabeludo/microbiologia , Trichophyton/classificação , Trichophyton/genética , Adolescente , Criança , Pré-Escolar , Estudos Transversais , DNA Fúngico/genética , Feminino , Humanos , Lactente , Masculino , Microsporum/citologia , Técnicas de Tipagem Micológica/normas , Especificidade da Espécie , Tinha do Couro Cabeludo/diagnóstico , Trichophyton/citologia , UgandaRESUMO
INTRODUCTION: Vietnam is a tropical country so fungal diseases including dermatophytosis may be prevalent, but epidemiological profiles of agents responsible for the infection have rarely been reported. OBJECTIVE: To find out the distribution of dermatophytes among patients living in a central province of Vietnam. METHODS: We examined dermatophyte infections in patients with lesions suspected of dermatophytosis referred to the Nghean provincial leprosy and dermatology centre from August 2015 to August 2016. The speciation of dermatophyte was performed by conventional and molecular approaches. RESULTS: One hundred and thirty-six patients (90 males and 46 females) were included. Those aged from 11 to 30 contribute 59.1%. The most common agent found was Trichophyton rubrum (66.9%), followed by T. interdigitale (12.5%), T. tonsurans (9.6%), Microsporum incurvatum (8.1%), and the less frequent species were M. canis (2.2%) and T. violaceum (0.7%). Epidermophyton floccosum was not reported. T. rubrum were more common in men (74.4%) than in women (52.2%), while T. interdigitale and M. incurvatum were more common in women (21.7 and 15.2%) than in men (7.8 and 4.4%). Patients infected with Microsporum spp. had small-sized lesions for only 3 months, while those affected by Trichophyton spp. had large-sized lesions with longer duration. CONCLUSION: Trichophyton species are the predominant agents of infection in Nghean province, while Epidermophyton species is absent. Additional investigations are required to clarify the epidemiological profile of dermatophytes in Vietnam.
Assuntos
Arthrodermataceae/isolamento & purificação , Dermatomicoses/epidemiologia , Microsporum/isolamento & purificação , Trichophyton/isolamento & purificação , Adolescente , Adulto , Criança , Dermatomicoses/microbiologia , Epidermophyton , Feminino , Humanos , Masculino , Microsporum/classificação , Pele/microbiologia , Trichophyton/classificação , Clima Tropical , Vietnã/epidemiologia , Adulto JovemRESUMO
Microsporum gypseum complex is a group of geophillic dermatophytes with a worldwide distribution and is a rare cause of dermatomycoses in humans. The infection most commonly presents as tinea corporis, with some geographical and occupational variations. We studied M. gypseum complex infections in patients examined in the Mycological Laboratory of the Department of Dermatovenereology, University Medical Centre Ljubljana, during the period 2000-2015. Diagnosis was confirmed by mycological examination. Skin scales were examined by direct microscopy and cultivated on Sabouraud glucose agar. A total of 226 patients were identified, representing 1.5% of all dermatophyte infections during the study period. Tinea corporis was diagnosed in majority of patients, followed by tinea manus, tinea faciei, tinea inguinalis and tinea pedis. Tinea capitis was observed in three and onychomycosis in two patients only. Infection was disseminated on different parts of the body in nine patients. In 39% of patients, infection was diagnosed in children younger than 9 years. Face and scalp infection was more often observed in children. The incidence was the highest during July and October. Contacts with soil and domestic animals were often reported. Data on the prevalence and clinical characteristics of M. gypseum complex infection in other countries are reviewed.
Assuntos
Microsporum/isolamento & purificação , Onicomicose/epidemiologia , Tinha/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Face/microbiologia , Feminino , Humanos , Lactente , Masculino , Microsporum/classificação , Pessoa de Meia-Idade , Onicomicose/microbiologia , Couro Cabeludo/microbiologia , Pele/microbiologia , Eslovênia/epidemiologia , Microbiologia do Solo , Tinha/microbiologia , Adulto JovemRESUMO
Type and reference strains of members of the onygenalean family Arthrodermataceae have been sequenced for rDNA ITS and partial LSU, the ribosomal 60S protein, and fragments of ß-tubulin and translation elongation factor 3. The resulting phylogenetic trees showed a large degree of correspondence, and topologies matched those of earlier published phylogenies demonstrating that the phylogenetic representation of dermatophytes and dermatophyte-like fungi has reached an acceptable level of stability. All trees showed Trichophyton to be polyphyletic. In the present paper, Trichophyton is restricted to mainly the derived clade, resulting in classification of nearly all anthropophilic dermatophytes in Trichophyton and Epidermophyton, along with some zoophilic species that regularly infect humans. Microsporum is restricted to some species around M. canis, while the geophilic species and zoophilic species that are more remote from the human sphere are divided over Arthroderma, Lophophyton and Nannizzia. A new genus Guarromyces is proposed for Keratinomyces ceretanicus. Thirteen new combinations are proposed; in an overview of all described species it is noted that the largest number of novelties was introduced during the decades 1920-1940, when morphological characters were used in addition to clinical features. Species are neo- or epi-typified where necessary, which was the case in Arthroderma curreyi, Epidermophyton floccosum, Lophophyton gallinae, Trichophyton equinum, T. mentagrophytes, T. quinckeanum, T. schoenleinii, T. soudanense, and T. verrucosum. In the newly proposed taxonomy, Trichophyton contains 16 species, Epidermophyton one species, Nannizzia 9 species, Microsporum 3 species, Lophophyton 1 species, Arthroderma 21 species and Ctenomyces 1 species, but more detailed studies remain needed to establish species borderlines. Each species now has a single valid name. Two new genera are introduced: Guarromyces and Paraphyton. The number of genera has increased, but species that are relevant to routine diagnostics now belong to smaller groups, which enhances their identification.
Assuntos
Epidermophyton/classificação , Epidermophyton/genética , Microsporum/classificação , Microsporum/genética , Filogenia , Trichophyton/classificação , Trichophyton/genética , Animais , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Variação Genética , Humanos , Fatores de Alongamento de Peptídeos/genética , Proteínas Ribossômicas/genética , Análise de Sequência de DNA , Tinha/microbiologia , Tubulina (Proteína)/genéticaRESUMO
Occurrence and diversity of dermatophyte mycoflora in 298 soil samples from Ahvaz, Southwest of Iran was investigated by using the hair-baiting technique. The samples were collected during spring (n = 210) and autumn (n = 88) of 2015, and the fungal isolates were identified based on the macro- and micro-morphology of colonies and with further ITS-rDNA RFLP and sequencing. Totally, 60 soil samples (20.1%) were positive for dermatophyte growth whose pH varied from 7.0 to 7.9. The highest (26.6%) and the lowest (14.3%) recovery rates were from the animal resorts and the streets soils samples, respectively. Seasonally, 16.7% of the spring samples and 28.4% of the autumn samples were positive. Based on molecular identification, three species of two genera were identified viz. M. fulvum (n = 57), M. canis (n = 2) and zoophilic Trichophyton interdigitale (n = 1). As a specific goal in the study, differentiation of the species in Microsporum gypseum complex was established by measuring the mean length and width of macroconidia in some strains of M. gypseum, M. fulvum and M. incurvatum. Mean size for macroconidia length and width in three species showed that M. gypseum and M. incurvatum can morphologically be differentiated from M. fulvum but not from each other. M. fulvum was the most abundant species isolated from the soils of Ahvaz; however, to comprehensively specify the distribution pattern of geophilic dermatophytes in the soils of this city further investigations are needed. Identification based on micro-morphometric is not effective for species distinction in M. gypseum complex, while molecular procedures based on sequencing of certain DNA regions are the most reliable and applicable strategies for this purpose.
Assuntos
Microsporum/classificação , Microsporum/isolamento & purificação , Microbiologia do Solo , Trichophyton/classificação , Trichophyton/isolamento & purificação , Animais , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Irã (Geográfico) , Técnicas Microbiológicas , Microsporum/genética , Microsporum/crescimento & desenvolvimento , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Estações do Ano , Análise de Sequência de DNA , Trichophyton/genética , Trichophyton/crescimento & desenvolvimentoRESUMO
A 10-year-old girl suffered from tinea corporis with erythematosquamous and centrifugal growing, sparse itching lesions of her right lower arm. Fluorescence optical Blankophor® preparation from skin scrapings revealed fungal hyphae. On Sabouraud's dextrose agar, the fast growing dermatophyte formed flat, peripheral radiating and convolved colonies with white, slightly yellowish to beige brown stained granular and powdery surface. The reverse side of the colonies was smooth with luminous yellow colour. Microscopically, an attitude of thin-walled spindle-shaped and echinulate (with small spins) and lanceolate macroconidia appeared. The small based macroconidia are raised in the middle and end part, however, pointy at the end ("spearhead"). Three to six or seven across septae are formed. The small piriform microconidia had an orthotropic arrangement. Chlamydospores were also formed. Urease activity was positive. Macromorphologically, Trichophyton (T.) interdigitale (formerly T. mentagrophytes) was suspected. Due to the shape of macroconidia, Microsporum (M.) gypseum and M. fulvum were also considered as possible species identification. Direct uniplex-PCR-EIA of the strains revealed negative results for T. rubrum, T. interdigitale, T. anamorph of Arthroderma benhamiae and M. canis. Sequencing analysis of the ribosomal ITS-region (18 S rRNA, ITS1, 5.8 S rRNA, ITS2, 28 S rRNA) and of the translation elongation factor 1alpha (tef-1-alpha) gene revealed the dermatophyte species M. praecox. Topical treatment was done using ciclopiroxolamine cream. M. praecox represents a geophilic dermatophyte, morphologically resembling M. gypseum. Horses are often the source of infection. In humans, M. praecox causes tinea corporis and tinea capitis. For oral treatment of dermatomycosis due to M. praecox, griseofulvin and terbinafine can be used.
Assuntos
Dermatomicoses/diagnóstico , Dermatomicoses/microbiologia , Microsporum/isolamento & purificação , Administração Tópica , Antifúngicos/administração & dosagem , Criança , Ciclopirox , Dermatomicoses/tratamento farmacológico , Diagnóstico Diferencial , Feminino , Humanos , Microsporum/classificação , Microsporum/efeitos dos fármacos , Piridonas/administração & dosagem , Doenças Raras/diagnóstico , Doenças Raras/tratamento farmacológico , Doenças Raras/microbiologia , Resultado do TratamentoRESUMO
AIMS: The aim of this study was to evaluate the performance of a commercially available multiplex RT-PCR assay for the rapid detection and identification of dermatophytes directly from clinical samples and cultures. METHODS AND RESULTS: The multiplex RT-PCR assay was used to evaluate 118 clinical isolates from various specimen types and a total of 140 known specimens were compared with both conventional methods, commercially available PCR-REBA, and ITS sequence analysis. In this study, multiplex RT-PCR assay yield significantly more positive results than culture (91·9 vs 39·5%) and conventional methods including KOH microscopy (91·9 vs 71·3%). Although the results among the multiplex RT-PCR, PCR-REBA and ITS sequence analysis were concordant (100%) in 118 clinical isolates, concordant results between multiplex RT-PCR assay and culture were at 66% (78/118). The overall positive rates for the PCR-REBA, multiplex RT-PCR assay and ITS sequence analysis were 98·8, 91·9, and 52·9% respectively. In addition, the concordance rate of multiplex RT-PCR assay and the PCR-REBA assay was 93% (95% confidence interval (CI), 89·9-96·1, P < 0·0001), 93·7% (95% CI, 90·5-96·4, P < 0·0001) sensitivity, 100% (95% CI, 80·0-100, P < 0·0001) specificity, and 99·6% positive and 81% negative predictive values, respectively. Among the 258 samples, the most frequently identified dermatophyte species were Trichophyton rubrum (n = 199, 77·1%) and Trichophyton mentagrophytes (n = 28, 10·9%). CONCLUSIONS: The entire multiplex RT-PCR procedure takes about 3 h, while results from culture can take up to 2-3 weeks. The use of the multiplex RT-PCR molecular diagnostic assay was rapid and reliable for detecting pathogen infections. SIGNIFICANCE AND IMPACT OF THE STUDY: Even though the use of molecular diagnostic technology is more expensive than conventional methods, the clinical and economic benefit of saving time relative to expense remains to be elucidated. Therefore, the multiplex RT-PCR assay may provide the essential information to accelerate therapeutic decisions for earlier and adequate antibiotic treatment in the acute phase of fungal pathogen infections.
Assuntos
Microsporum/isolamento & purificação , Reação em Cadeia da Polimerase Multiplex/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Dermatopatias/microbiologia , Trichophyton/isolamento & purificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , DNA Fúngico/genética , Feminino , Humanos , Masculino , Microsporum/classificação , Microsporum/genética , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Dermatopatias/diagnóstico , Trichophyton/classificação , Trichophyton/genética , Adulto JovemRESUMO
A 4-year-old Iranian boy developed erythematous, itchy and annular lesion on his face. Microscopic examination of the scraped samples with 10 % potassium hydroxide (KOH) revealed fungal septate hyphae and arthroconidia. The etiological agent was found to be Microsporum gypseum in mycological examinations. Amplification and restriction digestion of the internal transcribed spacers (ITS) of rDNA was not helpful for identification, but in ITS sequencing the isolate showed 98 % homology to Microsporum incurvatum strain CBS 172.64. Empirical treatment of the patient with griseofulvin for 4 weeks was successful. Other than our isolate, the ITS1 sequences of 38 strains from related species were retrieved from GenBank and phylogenetic tree using maximum likelihood method was constructed. The case isolate clustered apart from other strains of M. incurvatum. Pairwise comparison of ITS1 showed intraspecies variations of 0-13 nucleotides among M. incurvatum strains and an extensive interspecies variation of 33-80 bp and remarkable interspecies size polymorphism between the three sister species in the M. gypseum complex. The high level of ITS1 intraspecific variation is suitable for species identification rather than phylogeographic analysis of M. gypseum complex.
Assuntos
Microsporum/isolamento & purificação , Doenças Negligenciadas/diagnóstico , Doenças Negligenciadas/microbiologia , Tinha/diagnóstico , Tinha/microbiologia , Antifúngicos/administração & dosagem , Pré-Escolar , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Face/patologia , Griseofulvina/administração & dosagem , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Microscopia , Microsporum/classificação , Microsporum/genética , Dados de Sequência Molecular , Doenças Negligenciadas/tratamento farmacológico , Doenças Negligenciadas/patologia , Filogenia , Análise de Sequência de DNA , Tinha/tratamento farmacológico , Tinha/patologia , Resultado do TratamentoRESUMO
Skin diseases affect millions of people and animals worldwide, including Asian elephants. This study sought to determine the pathogen of skin diseases that occurred in Asian elephants in Chongqing Zoo, China. The isolated fungus was identified through its cultural characteristics, morphology, and polymerase chain reaction (PCR) amplification. The PCR amplification using common fungal primers (ITS1 and ITS4) determined that the pathogen was 99.7% homologous to Microsporum canis. This is the first report on elephants infected with Microsporum canis in China.
Assuntos
Animais de Zoológico , Dermatomicoses/veterinária , Elefantes , Microsporum/classificação , Animais , China/epidemiologia , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Dermatomicoses/epidemiologia , Dermatomicoses/microbiologia , Microsporum/genética , Microsporum/isolamento & purificaçãoRESUMO
We report a case of dermatophytosis caused by Microsporum persicolor in a 38-year-old male from Poland. Direct microscopic examination revealed high amounts of fungal hyphae from the right elbow material. The mould recovered in multiple cultures was identified as Microsporum persicolor by molecular identification based on partial of ß-tubulin gene (BT2), internal transcribed spacer, partial small ribosomal subunit (SSU) and large ribosomal subunit, partial translation elongation factor (TEF1) and RNA polymerase second largest subunit (RPB1) loci sequence data. The patient was treated with terbinafine. Clinical and mycological cure was achieved with this regimen and the patient was subsequently followed for 1 year without relapse. Microsporum persicolor is a very rare causative agent of dermatophytosis worldwide. The source of infection for the patient remained unclear and zoonotic transmission could not be confirmed.