In vitro activities of antifungal agents against clinical isolates of dermatophytes from animals.

Although the susceptibility of dermatophytes to antifungal drugs is well documented in humans, the effectiveness in animals has not been previously investigated. The in vitro susceptibility of 54 clinical isolates from animal dermatophytoses to ketoconazole (KTZ), itaconazole (ITZ) and terbinafine (TFN) was measured using microdilution assay (CLSI M38-A2 test) and by the E-test (KTZ and ITZ). All 3 drugs showed antifungal activity, while KTZ displayed the broadest minimum inhibition concentration (MIC) range (0.125-16 μg/ml) against M. canis and M. gypseum. The MIC of KTZ and ITZ was almost the same for human and animal isolates of T. mentagrophytes and T. rubrum. The MIC of TFN was almost the same for dermatophytes isolated from humans and animals.