In vitro growth-inhibitory activity of pneumocandins L-733,560 and L-743,872 against putatively amphotericin B- and fluconazole-resistant Candida isolates: influence of assay conditions
Abstract
L-733,560 and L-743,872 are water-soluble pneumocandins with potent antifungal activity. By beginning with the NCCLS M27-T method and varying test format (microdilution vs macrodilution), time of reading (24 h vs 48 h), and test medium (RPMI 1640 vs Antibiotic Medium 3), we have demonstrated that the MICs for these compounds can be altered significantly: the microdilution format, reading after 24 h and use of Antibiotic Medium 3 all reduced the measured MIC. No cross-resistance was demonstrated with either fluconazole or amphotericin B.