Identificação e determinação do perfil de suscetibilidade a antifúngicos de leveduras e fungos filamentosos isolados de dermatomicoses e avaliação da produção de proteinases e fosfolipases pelas leveduras

Abstract

Dermatomycosis are fungal infections localized in the skin, nails and hair that affect about 20 to 25% of the worldwide population. The prevalence of these infections varies according with the difference regionals and currently they have been considered an important public health issue in some regions of the world. Dermatomycosis can be caused by yeast, dermatophytes and non-dermatophyte filamentous fungi. The treatment of dermatological mycosis is based in the use of topical and/or oral antifungals however, the occurrence of treatment failure is common and cases of antifungal drug resistance have been reported. The aims of this study were to identify and determine the antifungal susceptibility profile of yeast and filamentous fungi isolated from dermatomycosis in the Uberaba-MG, and to evaluate the production of proteinases and phospholipases by yeasts. The fungal samples were obtained from patients attended in the service of clinical pathology of Universidade Federal do Triângulo Mineiro or in private laboratory of Uberaba. The fungi were identified by using classical methods and the in vitro antifungal susceptibility testing was evaluated by broth microdilution according recommended by the Clinical Laboratory Standards Institute (CLSI) by documents M27-A3 and M38-A2. Antifungal agents tested included ketoconazole, fluconazole, griseofulvin, itraconazole, terbinafine and voriconazole. The production of phospholipases and proteinases was analyzed for yeasts. Between July 2009 to July 2011 were analyzed 216 samples of which the majority was from women and adults between 31 to 60 years. The most common infection was onychomycosis followed by tinea pedis and tinea corporis. The fungi isolated were yeast (53.7%), dermatophytes (32.4%) and non-dermatophyte filamentous fungi (13.9%), and the most common species were Candida parapsilosis (24.07%), Trichophyton rubrum (17.13%), Trichophyton interdigitale (11.12%) and Candida guilliermondii (11.12%). The most of yeasts were susceptible to antifungals although susceptibility dose dependent has been found, mainly to itraconazole. Terbinafine was the most active compound against dermatophytes and the fluconazole showed the lower activity against these fungi. Nondermatophyte filamentous fungi showed the highest minimum inhibitory concentration (MIC) values to all antifungal agents. Of all Candida spp. evaluated, 29.8% were able to produce phospholipases and 42.3% produced proteinases. Among Trichosporon spp., 66.7% were producers of phospholipases and 16.67% producers of proteinases. However, our results did not relationship between the clinical origin of the isolates and their ability to produce exoenzymes. These data suggest that the identification of fungi and the antifungal susceptibility testing are procedures that could contribute to the success of therapy of dermatomycosis.