M44-A

Method for Antifungal Disk Diffusion Susceptibility Testing of Yeasts; Approved Guideline

NCCLS broth dilution reference methods are available for susceptibility testing of yeasts (see NCCLS document M27 - Reference Method for Broth Dilution Antifungal Susceptibility Testing of Yeasts) and moulds (see NCCLS document M38 - Reference Method for Broth Dilution Antifungal Susceptibility Testing of Filamentous Fungi). There still remains, however, a need for an alternative simple, rapid, and cost-effective approach to determine susceptibility of fungal organisms to various classes of antifungal agents that would make antifungal susceptibility testing more readily available to the clinical microbiology laboratory. The NCCLS Subcommittee on Antifungal Susceptibility Testing has developed a disk diffusion method for testing Candida species to fluconazole and voriconazole. Zone interpretive criteria (breakpoints) have been approved for fluconazole as well as quality control parameters for both fluconazole and voriconazole. One significant advantage of this method is that fluconazole and voriconazole. One significant advantage of this method is that qualitative results can usually be determined after only 20 to 24 hours incubation as opposed to 48 hours with NCCLS document M27. There are currently more than ten systemically active antifungal agents and it is expected that this document will further encourage the development of disk diffusion testing for at least some of these agents.