25º Congresso Brasileiro de Microbiologia

25º Congresso Brasileiro de Microbiologia

ResumoID:1178-2

Área: Microbiologia Clinica ( Divisão A )

IDENTIFICATION AND ANTIFUNGAL SUSCEPTIBILITY PROFILE OF CLINICAL TRICHOSPORON STRAINS.

Fábio Santos (IPEC/Fiocruz); Marília Nishikawa (INCQS/Fiocruz); Bruna Dias (IPEC/Fiocruz); Penha Sueli Florido (Estácio); Rodrigo Almeida Paes (IPEC/Fiocruz)

Resumo

Nowadays, clinical relevance of genus Trichosporon and its ability to cause invasive infections in immunocompromised patients are highly recognized among emerging pathogens. There are several methods for Trichosporon species identification, including morphologic studies, biochemical tests and molecular tools. Phenotipical methods are more adequate for use on microbiology laboratories, however, for identification of Trichosporon spp. its use is of low value. Despite the increasing number of refractary Trichosporon infections to conventional antifungal drugs, there are a few in vitro studies about susceptibility of this genus to antifungals . Difficulties on species identification on this genus as well no standardization of in vitro susceptibility tests contibute to scarce information available on this subject. The aim of the present study is the identification on the species level of Trichosporon strains from the mycological collection of the Instituto de Pesquisa Clínica Evandro Chagas of Fundação Oswaldo Cruz and to check their antifungal susceptibility profile, showing all the tests necessary to the complete identification in the laboratories of the clinical relevant species of this genus. Methodologies used included morphological, biochemical and physiological characterization. Antifungal susceptibility tests used were M44-A, M27-A2, E-test, and the commercialy available ATB-FUNGUS 3. Antifungal drugs tested were ketoconazole, itraconazole, fluconazole as well as amphotericin B and 5-fluocytosine. We identified 4/10 Trichosporon ovoides, 2/10 Trichosporon asteroides, 2/10 Trichosporon inkin, 1/10 Trichosporon asahii and 1/10 Trichosporon mucoides. We observed good correlation between the methodologies and Trichosporon genus was very sensitive to ketoconazole. There was a good correlation between the methods on the analyzes of the azoles fluconazole and itraconazole, however the minimal inhibitory concentrations are considered high, if compared to the standardized methodologies. In this study, the low activity of 5-fluocytosine was observed after 24 hours incubation and confirmed after 48 hours incubation on the CLSI methodologies. Amphotericin B presented good correlation between methodologies after 48 hours incubation and high inhibitory concentrations were obtained for this genus. The present study emphasizes the necessity of standardization of susceptibility test methodologies, as well as phenotipical identification techniques usefull on the microbiology laboratories.

Palavras-chave: antifungal drugs, identification, Trichosporon

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