Body length of Hylodes cf. ornatus and Lithobates catesbeianus tadpoles, depigmentation of mouthparts, and presence of Batrachochytrium dendrobatidis are related.

A fungal pathogen Batrachochytrium dendrobatidis (Bd), which can cause morbidity and death of anurans, has affected amphibian populations on a worldwide basis. Availability of pure cultures of Bd isolates is essential for experimental studies to understand the ecology of this pathogen. We evaluated the relationships of body length of Hylodes cf. ornatus and Lithobates catesbeianus tadpoles to depigmentation of mouthparts and determined if dekeratinization indicated an infection by Batrachochytrium dendrobatidis. A strong association existed for both species, one from South America (Brazil: São Paulo) and one from North America (USA: Maine). We believe it prudent not to kill adult amphibians if avoidable, thus obtaining tissue for isolating Bd from tadpoles is reasonable because infected specimens of some species can be selectively collected based on depigmentation of mouthparts.

Body length of Hylodes cf. ornatus and Lithobates catesbeianus tadpoles, depigmentation of mouthparts, and presence of Batrachochytrium dendrobatidis are related / Tamanho do corpo, despigmentação das partes bucais e presença de Batrachochytrium dendrobatidis estão relacionados em Hylodes cf. ornatus e Lithobates catesbeianus

A fungal pathogen Batrachochytrium dendrobatidis (Bd), which can cause morbidity and death of anurans, has affected amphibian populations on a worldwide basis. Availability of pure cultures of Bd isolates is essential for experimental studies to understand the ecology of this pathogen. We evaluated the relationships of body length of Hylodes cf. ornatus and Lithobates catesbeianus tadpoles to depigmentation of mouthparts and determined if dekeratinization indicated an infection by Batrachochytrium dendrobatidis. A strong association existed for both species, one from South America (Brazil: São Paulo) and one from North America (USA: Maine). We believe it prudent not to kill adult amphibians if avoidable, thus obtaining tissue for isolating Bd from tadpoles is reasonable because infected specimens of some species can be selectively collected based on depigmentation of mouthparts.

O fungo patógeno Batrachochytrium dendrobatidis (Bd) é apontado como o causador de morbidade e morte em anuros, e tem afetado populações de anfíbios em uma base mundial. Avaliar culturas puras de isolados de Bd é essencial para estudos experimentais para o entendimento da ecologia desse patógeno. Avaliou-se a relação entre o comprimento do corpo em girinos de Hylodes cf. ornatus e Lithobates catesbeianus com a despigmentação das peças bucais, para verificar se a desqueratinização indica uma infecção por Batrachochytrium dendrobatidis. Uma forte associação existe para ambas as espécies, uma da América do Sul (Brasil: São Paulo) e uma da América do Norte (USA: Maine). Acredita-se ser prudente este uso, para evitar a morte de anfíbios adultos; dessa forma, obter tecidos para isolar o Bd de girinos é razoável, porque espécimes infectados podem ser coletados seletivamente com base na despigmentação do aparelho bucal.

Investigation of Propionibacterium acnes in progressive macular hypomelanosis using real-time PCR and culture.

BACKGROUND: Progressive macular hypomelanosis (PMH) is a dermatosis of unknown etiology. It has been concluded that it involves the presence of Propionibacterium acnes, a saprophyte of the pilosebaceous follicles. In our study, we investigated the presence of P. acnes in lesional and non-lesional skin of patients with PMH through quantitative real-time polymerase chain reaction (PCR) and bacterial culture from a skin fragment. MATERIALS AND METHODS: An observational, exploratory study, with laboratory comparison of lesional (study group) and non-lesional skin (comparison group), in patients with PMH, was carried out with 36 patients, seen in the dermatology outpatient setting at the Oswaldo Cruz University Hospital (OCUH), Recife, Pernambuco, Brazil, between March and May 2008. All patients were submitted to a Wood's lamp examination, mycological research, and biopsies of lesional and non-lesional skin from the back. Skin fragments were submitted to a histopathology test, bacterial culture, and a quantitative real-time PCR test. The program Statistical Package for Social Sciences, version 12.0, was employed for relationship analysis with the Wilcoxon and McNemar tests. RESULTS: There was a significant predominance of P. acnes on lesional skin, in comparison to non-lesional skin (P<0.001), as demonstrated by culture and quantitative real-time PCR. CONCLUSION: Although P. acnes is a saprophyte, the hypothesis may be raised that this microorganism participates in the development of PMH.