Impact of culture medium on antifungal susceptibility results for Microsporum canis and Nannizzia gypsea: A comparative study of disc diffusion and E-test performance

This study evaluated the impact of culture media on antifungal susceptibility testing (AFST) for feline dermatophytes, specifically Microsporum canis and Nannizzia gypsea, using disc diffusion and E-test methods. A total of 28 isolates were tested, with 26 identified as M. canis and 2 as N. gypsea. The study found that both species were highly susceptible to posaconazole and voriconazole, but showed differing susceptibilities to other antifungals: M. canis was more susceptible to itraconazole, while N. gypsea was more susceptible to clotrimazole. Mueller-Hinton Agar (MHA) demonstrated high productivity rates and consistent colony morphology, making it a preferred medium over Dermasel Agar (DA) for AFST. This research provides valuable insights for evidence-based antifungal therapy and resistance monitoring.