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, Ceará , Brazil. The fungal characterization was performed by classical mycological examination and by genotypical analysis using the restriction enzymes Sau3A, RsaI, DdeI 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 mg ml "1 for griseofulvin, 0?25 mg ml "1 for ketoconazole and 1 mg ml "1 for itraconazole. This study emphasizes the adaptability of anthropophilic fungi such as T. tonsurans to animal conditions.
IntroductionDermatophytoses are the most common fungal infections in dogs and cats (Khosravi & Mahmoundi, 2003;Simpanya & Baxter, 1996). The dermatophytes have a high affinity for keratin, an important component of fur, skin and nails, which are the primary sites of fungal infection (Borgers et al., 2005). Clinical presentations of dermatophytic lesions include multifocal alopecia, mild or intense pruritus and round scaly lesions with erythematous and scaly borders (Cafarchia et al., 2004). According to their natural reservoir, dermatophytes are classified as anthropophilic, zoophilic or geophilic (De Hoog et al., 2000). Several reports have stated that Microsporum canis, a typical zoophilic species, is the most common dermatophyte isolated from dogs and cats worldwide (Brilhante et al., 2003;Cafarchia et al., 2004;Khosravi & Mahmoundi, 2003;Segundo et al., 2004). On the other hand, Trichophyton tonsurans is a classic anthropophilic species usually isolated from human dermatophytosis in northeast Brazil (Brilhante et al., 2004).This study describes a rare case of canine dermatophytosis caused by T. tonsurans. The fungal characterization was done by morphological and molecular analysis. In addition, an in vitro antifungal susceptibility test was performed.
Case reportA 2-year-old female Doberman Pinscher with suspected dermatophytosis was examined in a veterinary clinic located in Fortaleza, Ceará (northeast Brazil). The animal showed a rounded lesion of 3 cm in diameter, patches of scalp hair loss and scaling. The lesion was not inflamed, and it was in the distal portion of the right femoral region of the leg (Fig. 1a).Clinical specimens were obtained from the animal skin by scraping epidermal scales from the lesion with a surgical blade, and then transported to the Specialized Medical Mycology Center (Federal University of Ceará, Brazil). Direct microscopic examinations of the epidermal scales, using 30 % KOH, were negative for mites, but showed hyaline-septated arthroconidiate hyphae suggesting dermatophyte infection. Ectothrix or endothrix parasitism was...
