In vitro susceptibility of 15 strains of zygomycetes to nine antifungal agents as determined by the NCCLS M38-A microdilution method

The in vitro susceptibility of 15 strains of six genera of zygomycetes including Rhizopus oryzae (Rhizopus arrhizus), Rhizopus stolonifer, Mucor circinelloides (three), Absidia corymbifera (three), Rhizomucor pusillus (three), Cunninghamella bertholletiae (two), and Syncephalastrum racemosum (two) to nine antifungal agents were determined by the NCCLS M38-A broth microdilution method. Geometric means of the minimal inhibitory concentrations (MIC) were: amphotericin B 0.07 mg l(-1) (range 0.03-0.5 mg l(-1)), nystatin 0.83 mg l(-1) (range 0.25-4 mg l(-1)), itraconazole 0.59 mg l(-1) (range 0.03 to > 8 mg l(-1)), voriconazole 6.50 mg l(-1) (range 2 to > 8 mg l(-1)), ciclopiroxolamine 1.59 mg l(-1) (range 0.5-4 mg l(-1)), and amorolfine 9.19 mg l(-1) (range 1 to > 16 mg l(-1)). All strains were resistant to 5-flucytosine, fluconazole (MIC > 64 mg l(-1)) and caspofungin (MIC > 16 mg l(-1)).