In Vitro Susceptibility Testing of Different Antimycotics and Disinfectants against Microsporum canis Isolated from Clinical Cases of Feline Dermatophytosis

Abstract

Dermatophytosis is a common fungal condition of skin having zoonotic importance. Unconventional use of antimycotics and persistence in environment due to improper disinfection often leads to resistance and treatment failure. The purpose of this study was to observe in-vitro efficacy of different antimycotics and disinfectants against Microsporum canis. Skin scraping samples from affected cats were cultured and purified. Conidia were harvested from cultured colonies and count of 1.0 x 106/mL was adjusted by hemocytometer. Harvested conidial suspensions were inoculated on Mueller Hinton Agar (MHA) with antimycotic disks and incubated, then inhibition zone diameters were measured. Same conidial suspensions were inoculated with each disinfectant separately on Dermatophyte Test Medium (DTM) petri plates and colonies were enumerated after incubation. The data suggested that Itraconazole had maximum in-vitro effect followed by Miconazole, Clotrimazole and Ketoconazole, whereas Fluconazole demonstrated resistance. On the other hand, 5% phenol, 3% Hydrogen Peroxide, 1:10 sodium hypochlorite solutions were equally effective against M. canis spores.