Skin lesions in dogs and cats with coccidioidomycosis in Arizona

Abstract

BACKGROUND: Coccidioidomycosis is a fungal disease caused by the dimorphic saprophytic fungus Coccidioides immitis or C. posadasii. Primary pulmonary infection can disseminate to cutaneous and subcutaneous tissues, or less commonly direct cutaneous inoculation may occur. HYPOTHESIS/OBJECTIVES: To characterize the historical, clinical, diagnostic and treatment findings in dogs and cats with cutaneous manifestation of coccidioidomycosis. ANIMALS: Twenty three dogs and seventeen cats diagnosed between 2009 and 2015 in Arizona, USA. METHODS: Retrospective review of medical records from dogs and cats from an endemic area with a confirmed diagnosis via histopathology, cytology and/or culture, and skin lesions. RESULTS: Age of affected dogs ranged from 14 weeks to 13 years (median = 7 years), whereas cats ranged from 3 to 17 years (median = 9 years). Subcutaneous nodules were the most common lesions in both species. Lesions were distributed widely and not often found over sites of bone infection. In 75% of dogs and 54.5% of cats with cutaneous lesions there were clinical signs of systemic illness, supporting the diagnosis of cutaneous disseminated disease. Four dogs and four cats had localized lesions with no systemic illness, consistent with possible primary cutaneous infection. The most common mode of diagnosis was cytology identification in both species. Fluconazole was the most commonly prescribed antifungal drug. CONCLUSIONS AND CLINICAL IMPORTANCE: Coccidioidomycosis is the most common mycosis of dogs and cats in endemic regions and cutaneous signs of the disease may be an initial presenting complaint. This study identified a variety of cutaneous manifestations of the disease in dogs and cats and should be recognized by clinicians.