Potential fungicidal effect of voriconazole against Candida spp.

In vitro fungistatic and fungicidal activities of voriconazole were evaluated against 114 isolates of Candida spp. MICs were determined using the NCCLS M27-A2 broth microdilution method. Minimum fungicidal concentrations (MFCs) were defined as the lowest drug concentrations that yielded ≤5 colonies (≥98% killing activity). The fungicidal activity could be only evaluated against 45.6% of the isolates (52 of 114 isolates) because trailing growth occurred, and 30 of these 52 isolates (57.69%) showed MFC values ≤1 mg/l. There was little or no fungicidal activity against C. albicans and C. tropicalis. In contrast, all C. krusei were killed by 1-2 mg/l voriconazole. In conclusion, our data show that the fungicidal effect of voriconazole against Candida spp. is species dependent.