Fungal Pathogens in Pet Dogs and Cats in Grenada: Identification and Antifungal Susceptibility

Considering the clinical relevance of commensal yeasts (Malassezia and Candida) and zoophilic dermatophytes (Microsporum canis and Trichophyton mentagrophytes) in dogs and cats, this study determines the prevalence of fungal species involved in ear and superficial skin infections in dogs and cats in Grenada and examines their antifungal susceptibility. The etiological agents were isolated from ear, skin, and hair samples of suspected clinical fungal cases using Sabouraud Dextrose Agar (SAB). The isolates’ identification comprised morphological, biochemical, and molecular methods encompassing micro-/macroscopy analysis. Biochemically, yeast isolates were identified by the BD Phoenix M50 microbial identification system, and additional validation of all fungal isolates was performed by polymerase chain reaction (PCR) and sequencing of the ITS region. Furthermore, the E-Test (Epsilometer Test) was used to determine the susceptibility patterns for four azole drugs: ketoconazole, itraconazole, fluconazole, and voriconazole. A total of 405 samples (266 ear, 61 skin, and 78 hair) were collected from 136 dogs and 43 cats. The identified species were Malassezia pachydermatis, Candida tropicalis, and Trichophyton spp. All isolates demonstrated (100%) resistant activity to fluconazole. Importantly, this knowledge will significantly contribute to our understanding of the epidemiology of fungal infections as well as provide guidelines for preventive measures against fungal infections in Grenada.