Efficacy of griseofulvin and itraconazole in the treatment of experimentally induced dermatophytosis in cats

Abstract

Summary To evaluate the efficacy of itraconazole and griseofulvin in the treatment of Microsporum canis infection, 15 juvenile cats were infected by topical application of 105 live M canis macroconidia to the skin of the lateral part of the trunk, and an occlusive bandage was applied. After 3 weeks, cats were randomly assigned to 1 of 3 treatment groups (n = 5 each): cats in the first group received griseofulvin (50 mg/kg of body weight, po, q 24 h); the second group received itraconazole (10 mg/kg, po, q 24 h); and the third group (control) received an equivalent volume of vehicle (without drug, po, q 24 h). Treatment continued for 100 days, or until mycologic cure (lack of dermatophyte isolation on 3 consecutive weekly fungal cultures) was achieved. Infection in all cats peaked in severity at week 6 after inoculation, then gradually resolved over the next 11 weeks. The itraconazole-treated group was the first to achieve a cure, after receiving 56 days of treatment, followed by the griseofulvin-treated group at 70 days. None of the cats in the control group reached mycologic cure after 100 days of treatment. As early as day 14 of treatment, the griseofulvin- and itraconazole-treated groups had significantly (P < 0.05) lower mean infection scores, compared with those in the control group. Significant differences in the mean infection scores between the itraconazole- and griseofulvin-treated groups were not found. This study revealed that griseofulvin and itraconazole, each as sole treatment, significantly altered the course of infection, compared with that in a vehicle-treated control group. Both drugs were effective in the treatment of experimentally induced dermatophytosis in cats.