In vitro activities of voriconazole (UK-109,496) against fluconazole-susceptible and -resistant Candida albicans isolates from oral cavities of patients with human immunodeficiency virus infection

The susceptibility of Candida albicans to a new antifungal triazole, voriconazole (UK-109,496), was investigated in 105 isolates obtained from the oral cavities of patients with human immunodeficiency virus (HIV) infection to study this drug's activity against fluconazole-susceptible and -resistant isolates, MICs were determined by a broth microdilution technique according to document M27-T from the National Committee for Clinical Laboratory Standards and by using a broth microdilution technique and a synthetic high-resolution medium, These antifungal susceptibility testing methods showed high levels of agreement (93% for fluconazole and 86% for voriconazole), Data from in vitro studies showed that voriconazole has good activity against fluconazole-susceptible and -resistant C, albicans isolates; the MICs at which 90% of all isolates were inhibited were 0.19 to 0.39 mu g/ml. We found that for isolates for which fluconazole MICs were high, voriconazole MICs were proportionally higher than those for fluconazole-susceptible C, albicans (P < 0.001), Pretreatment isolates from six patients with fluconazole-refractory esophageal candidiasis were included in the study. For these isolates the MICs were less than or equal to 0.39 mu g/ml, and all patients responded to voriconazole. These results suggest that voriconazole is effective even in the treatment of fluconazole refractory esophageal candidiasis and should be studied further to determine its clinical relevance in patients with HIV infection.