Multilocus differentiation of the related dermatophytes Microsporum canis, Microsporum ferrugineum and Microsporum audouinii

Rice grain is one of the world's most important food crops, and its cultivation is a major occupation in Anambra State, Nigeria. These rice farmers are exposed to various agents that predispose them to cutaneous mycoses. The aim of this work was to screen rice farmers for lesions suggestive of cutaneous mycoses and to isolate and identify fungal agents associated with the infection. This survey was carried out between November 2009 and June 2011 in Anambra State, Nigeria. Clinical samples collected from 201 farmers with lesions suggestive of cutaneous mycoses were processed and the organisms identified. Questionnaires were used to obtain other necessary data and were statistically analyzed. Of the 2,580 rice farmers screened, 201 (7.79%) showed positive lesions. Organisms recovered included Microsporum audouinii, Microsporum ferrugineum, Trichophyton megnini, Trichophyton tonsurans, Trichophyton rubrum, Aspergillus terrus, Aspergillus candidus, Aspergillus scleriotorum, Aspergillus niger, Aspergillus flavus, Scopulariopsis sp., Chrysosporium sp., Eupenicillium javanicum, Fusarium sp., Penicillium aculeatum, and Penicillium pinophilum. At the end of this work, onychomycosis was observed to be the most prevalent with nondermatophyte molds now becoming very important agents of cutaneous mycoses among rice farmer.

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Dermatophyten-Infektionen der Haut, Haare und Nägel bei Kindern – ein Update

Kinder- und Jugendmedizin ◽

10.1055/s-0038-1629344 ◽

2013 ◽

Vol 13 (04) ◽

pp. 262-269 ◽

Cited By ~ 3

Author(s):

C. Krüger ◽

I. Schulze ◽

B. Lietzberg ◽

H. Friedlein ◽

G. Ginter-Hanselmayer ◽

...

Keyword(s):

Tinea Capitis ◽

Trichophyton Mentagrophytes ◽

Microsporum Canis ◽

Trichophyton Verrucosum ◽

Trichophyton Tonsurans ◽

Arthroderma Benhamiae ◽

Trichophyton Erinacei ◽

Microsporum Audouinii ◽

Tinea Gladiatorum ◽

Zoophile Dermatophyten

ZusammenfassungDas klinische Spektrum und die Erreger der Dermatophytosen unterscheiden sich deutlich zwischen Kindern und Erwachsenen. Im Gegensatz zu Erwachsenen, bei denen die Tinea pedis die häufigste Pilzinfektion der Haut darstellt, werden bei Kindern vor allem die Tinea corporis und Tinea capitis diagnostiziert. Eine neue und beunruhigende Entwicklung ist die Zunahme der Onychomykose – meist durch Trichophyton rubrum – im Kindesalter. Die Tinea capitis stellt eine diagnostische und vor allem therapeutische Herausforderung für Kinderärzte und auch Dermatologen dar. Erreger der Tinea capitis sind in Deutschland vorzugsweise zoophile Dermatophyten. An erster Stelle steht Microsporum canis, das Verhältnis verschiebt sich jedoch mehr und mehr zu den zoophilen Trichophyton-Arten, z. B. Trichophyton interdigitale (früher Trichophyton mentagrophytes). Trichophyton species von Arthroderma benhamiae ist ein neuer Erreger, der im Kindesalter wahrscheinlich mittlerweile alle anderen zoophilen Dermatophyten in Bezug auf die Häufigkeit überflügelt hat. Seltener werden Trichophyton verrucosum – Erreger der „Kälberflechte“ – und Trichophyton erinacei („Igelpilz“) isoliert. Anthropophile Erreger, wie Microsporum audouinii und Trichophyton tonsurans, müssen Anlass sein, nach der Infektionsquelle zu fahnden. Das kann ein familiärer Immigrationshintergrund sein oder auch die Infektion in einem Kampfsportverein (Tinea gladiatorum capitis et corporis).

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A new molecular marker for species-specific identification of Microsporum canis

Brazilian Journal of Microbiology ◽

10.1007/s42770-020-00340-y ◽

2020 ◽

Vol 51 (4) ◽

pp. 1505-1508

Author(s):

Anita Ciesielska ◽

Paweł Stączek

Keyword(s):

Fungal Growth ◽

Electrophoretic Analysis ◽

Microsporum Canis ◽

Pcr Assay ◽

Source Of Infection ◽

Microsporum Audouinii ◽

Microscopy Analysis ◽

Species Specific ◽

Dermatophyte Species ◽

Positive Results

AbstractSpecies identification of dermatophytes by conventional mycological methods based on macro- and microscopy analysis is time-consuming and has a lot of limitations such as slow fungal growth or low specificity. Thus, there is a need for the development of molecular methods that would provide reliable and prompt identification of this group of medically important fungi. The are many reports in the literature concerning PCR identification of dermatophyte species, but still, there are not many PCR assays for the separate detection of members of the genera Microsporum, especially Microsporum canis (zoophilic species) and Microsporum audouinii (anthropophilic species). The correct distinction of these species is important to determine the source of infection to implement the appropriate action to eliminate the path of infection transmission. In this paper, we present such a PCR-based method targeting velB gene that uses a set of two primers—Mc-VelB-F (5′-CTTCCCCACCCGCAACATC-3′) and Mc-VelB-R (5′-TGTGGCTGCACCTGAGAGTGG-3′). The amplified fragment is specific due to the presence of (CAGCAC)8 microsatellite sequence only in the velB gene of M. canis. DNA from 153 fungal samples was used in PCR assay followed by electrophoretic analysis. The specificity of the designed set of primers was also confirmed using the online BLAST-Primer tool. The positive results were observed only in the case of M. canis isolates, and no positive results were obtained neither for other dermatophytes and non-dermatophyte fungi nor for other Eukaryotes, including the human genome sequence, as well as the representatives of bacterial and viral taxa. The developed PCR assay using the proposed Mc-VelB-F and Mc-velB-R primers can be included in the algorithm of M. canis detection in animals and humans.

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Epidemiologia das infeções fúngicas superficiais em Portugal - revisão de 3 anos (2014-2016)

Revista da Sociedade Portuguesa de Dermatologia e Venereologia ◽

10.29021/spdv.76.3.910 ◽

2018 ◽

Vol 76 (3) ◽

pp. 269-278 ◽

Cited By ~ 1

Author(s):

Margarida Rato ◽

Adelina Costin ◽

Constança Furtado ◽

Cristina Sousa ◽

Cristina Toscano ◽

...

Keyword(s):

Trichophyton Rubrum ◽

Microsporum Canis ◽

Trichophyton Soudanense ◽

Microsporum Audouinii

Introdução: As infeções fúngicas superficiais são as dermatoses infeciosas mais frequentes e a sua incidência continua a aumentar. Os dermatófitos são os principais agentes causais apresentando, contudo, uma distribuição geográfica variável.Material e Métodos: O presente estudo teve como objetivo a caracterização epidemiológica das infeções fúngicas superficiais diagnosticadas nos Serviços/Unidades de Dermatologia pertencentes ao Serviço Nacional de Saúde Português entre janeiro de 2014 e dezembro 2016 através da análise retrospetiva dos resultados das culturas realizadas durante esse período.Resultados: Foram estudados 2375 isolamentos, pertencentes a 2319 doentes. O dermatófito mais frequentemente isolado foi o Trichophyton rubrum (53,6%), tendo sido o principal agente causal da tinha da pele glabra (52,4%) e das onicomicoses (51,1%). Relativamente às tinhas do couro cabeludo, globalmente o Microsporum audouinii foi o agente mais prevalente (42,6%), seguido do Trichophyton soudanense (22,1%). Enquanto na área metropolitana de Lisboa estes dermatófitos foram os principais agentes de tinha do couro cabeludo, nas regiões Norte e Centro o agente mais frequente foi o Microsporum canis (58,5%). Os fungos leveduriformes foram os principais responsáveis pelas onicomicoses das mãos (76,7%).Conclusão: Os resultados deste estudo estão globalmente concordantes com a literatura científica. O Trichophyton rubrum apresenta-se como o dermatófito mais frequentemente isolado em cultura. Na tinha do couro cabeludo, na área metropolitana de Lisboa, as espécies antropofílicas de importação assumem particular destaque.

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Prevalence of Undetected Tinea Capitis in Household Members of Children with Disease

PEDIATRICS ◽

10.1542/peds.92.1.155 ◽

1993 ◽

Vol 92 (1) ◽

pp. 155-157

Author(s):

KAREN VARGO ◽

BERNARD A. COHEN

Keyword(s):

Tinea Capitis ◽

The United States ◽

Hair Shaft ◽

School Age Children ◽

Microsporum Canis ◽

Trichophyton Tonsurans ◽

The Past ◽

Microsporum Audouinii ◽

Household Members ◽

Black School

The epidemiology of tinea capitis has changed over the past 40 years. The major organism responsible for tinea capitis today is Trichophyton tonsurans. This dermatophyte accounts for more than 90% of ringworm infections of the scalp in the United States and replaces Microsporum audouinii and to a lesser extent Microsporum canis, which were associated with the ringworm epidemics of the 1940s.1-4 Trichophyton tonsurans is an anthropophilic organism producing endothrix invasion of the hair shaft that does not fluoresce on Wood's light examination.5 Tinea capitis is epidemic in black school-age children, but only rarely in whites. The reason for this racial predilection is not known.1

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