In-vitro antifungal susceptibilities of Basidiobolus and Conidiobolus spp. strains

The in-vitro antifungal susceptibilities of nine isolates belonging to Basidiobolus spp. and seven to Conidiobolus spp. against six antifungals (amphotericin B, ketoconazole, miconazole, itraconazole, fluconazole and flucytosine) were tested. A broth microdilution method, generally following the NCCLS guidelines, was used. Inoculum concentrations of the order of 100 cfu/mL were obtained by culturing fungi in a broth medium (Czapeck broth supplemented with 2% Tween 80 and 0.07% agar). MICs and MFCs were highly variable and isolate-dependent, with the exception of those of flucytosine which were constantly very high. In general, however, Basidiobolus spp. displayed low MICs of fluconazole, itraconazole, ketoconazole and miconazole, and Conidiobolus spp. were resistant to all antifungals tested.