Canine dermatophytosis caused by an anthropophilic species:: molecular and phenotypical characterization of Trichophyton tonsurans

Microsporum canis is the most common species isolated from canine and feline dermatophytosis in the world. However, this study reports a rare case of canine dermatophytosis caused by the anthropophilic dermatophyte Trichophyton tonsurans in the city of Fortaleza, Ceara , Brazil. The fungal characterization was performed by classical mycological examination and by genotypical analysis using the restriction enzymes Sau3A, RsaI, Ddel and EcoRI. The phenotypical characteristics were compatible with T tonsurans. The results obtained in the genotypical analysis were similar to the digestion pattern of the ITS sequences for T tonsurans strains. In addition, an antifungal susceptibility test was performed with griseofulvin, ketoconazole and itraconazole. The MICs were 0(.)5 mu g ml(-1) for griseofulvin, 0.25 mu g ml(-1) for ketoconazole and 1 mu g ml(-1) for itraconazole. This study emphasizes the adaptability of anthropophilic fungi such as T tonsurans to animal conditions.