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.
