American Society for Microbiology, Antimicrobial Agents and Chemotherapy, 10(61), 2017
DOI: 10.1128/aac.01057-17
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ABSTRACTClinical and Laboratory Standards Institute (CLSI) conditions for testing the susceptibilities of pathogenicSporothrixspecies to antifungal agents are based on a collaborative study that evaluated five clinically relevant isolates ofSporothrixschenckii sensu latoand some antifungal agents. With the advent of molecular identification, there are two basic needs: to confirm the suitability of these testing conditions for all agents andSporothrixspecies and to establish species-specific epidemiologic cutoff values (ECVs) or breakpoints (BPs) for the species. We collected available CLSI MICs/minimal effective concentrations (MECs) of amphotericin B, five triazoles, terbinafine, flucytosine, and caspofungin for 301Sporothrix schenckii sensu stricto, 486S. brasiliensis, 75S. globosa, and 13S. mexicanamolecularly identified isolates. Data were obtained in 17 independent laboratories (Australia, Europe, India, South Africa, and South and North America) using conidial inoculum suspensions and 48 to 72 h of incubation at 35°C. Sufficient and suitable data (modal MICs within 2-fold concentrations) allowed the proposal of the following ECVs forS. schenckiiandS. brasiliensis, respectively: amphotericin B, 4 and 4 μg/ml; itraconazole, 2 and 2 μg/ml; posaconazole, 2 and 2 μg/ml; and voriconazole, 64 and 32 μg/ml. Ketoconazole and terbinafine ECVs forS. brasiliensiswere 2 and 0.12 μg/ml, respectively. Insufficient or unsuitable data precluded the calculation of ketoconazole and terbinafine (or any other antifungal agent) ECVs forS. schenckii, as well as ECVs forS. globosaandS. mexicana. These ECVs could aid the clinician in identifying potentially resistant isolates (non-wild type) less likely to respond to therapy.