Large-Scale Evaluation of In Vitro Amphotericin B, Triazole, and Echinocandin Activity against Coccidioides Species from US Institutions

Large-scale testing of Coccidioides isolates has not been performed, and the frequency of clinical isolates with elevated amphotericin B or triazole MICs has not been evaluated. Coccidioides isolates (n = 581) underwent antifungal susceptibility testing. Elevated MIC values were observed for fluconazole (>= 16 mu g/ml, 37.3% of isolates; >= 32 mu g/ml, 7.9% of isolates), itraconazole (>= 2 mu g/ml, 1.0% of isolates), posaconazole (>= 1 mu g/ml, 1.0% of isolates), and voriconazole (>= 2 mu g/ml, 1.2% of isolates). However, mold-active triazoles exhibited low MICs for the majority of isolates tested. Additional correlation with patient outcomes to determine the relevance of elevated MICs in Coccidioides isolates is needed.