Susceptibility of nosocomial isolates of Candida species to LY121019 and other antifungal agents.

LY121019 is a novel analog of the polypeptide antifungal antibiotic echinocandin B. We investigated the in vitro activity of LY121019, amphotericin B, ketoconazole and 5-fluorocytosine against 131 nosocomial isolates of Candida species: C. albicans (n = 50), C. tropicalis (n = 30), C. rugosa (n = 12), C. parapsilosis (n = 11), C. lusitaniae (n = 10), C. guillermondii (n = 9), and C. krusei (n = 9). In vitro susceptibility testing was performed using a broth microdilution method. The minimal inhibitory concentrations (MIC) of LY121019 were less than or equal to that of the other antifungal agents against C. albicans and C. tropicalis but were generally higher for the other species of Candida. Paradoxical growth at high concentrations, but not at low concentrations, of LY121019 was observed with isolates of C. albicans and C. tropicalis.