Resumo

Fonsecaea pedrosoi is the most important agent of human chromoblastomycosis, a chronic subcutaneous fungal infection. Several medical therapies have been employd to treat chromoblastomycosis patients but long-term efficacy is still too low to allow specialists to elect a standard for treatment. Despite the clinical resistance there are few studies about the in vitro susceptibilities tests. The purpose of this study was to determine the susceptibility profile of the isolats of Fonsecaea pedrosoi by different techniques. Fifty- nine clinical isolates of Fonsecaea pedrosoi from fourteen patients with chromoblatomycosis were tested against voriconazole, itraconazole, and amphotericin B by Clinical Laboratory Standards Institute M38-A2 reference broth dilution method ( BMD ) and also by the E-test® methodology. The MICs were determined by the visual inspection and corresponded to complete growth inhibition for amphotericin B, and azoles ( 100% inhibition of growth ). The BDM - MICs of the drugs tested was amphotericin B ( the 90% minimal inhibitory concentration ) ( MIC90 ) was the 0,06 to 2 mg/L, itraconazole, range was the 0.015-0.5mg/L and voriconazole range was 0.015-0.5. For the E-test® the range of amphotericin B was the 0,012 - 2 mg/L, for the itraconazole was the 0.015-1mg/L and for voriconazole was the 0.015-0.12mg/L. When the test results are analyzed by patients observed that: sequential strains of the 2 patients with severe form of disease, showed MIC variation ( 0,03 mg/L for 0,5 mg/L ) for itraconazole; four cases with strains SDD (0,25 – 0,5 mg/L) for itraconazole and one resistant to voriconazole ( 0,25 mg/L ). These results show that patients in treated with itraconazole for long periods can lead to the emergence of strains acquired resistance and cross.