Cases of urinary tract infection (UTI) caused by Candida species are uncommon in dogs and cats. This study characterized infections from dogs and cats from three veterinary teaching hospitals. Six species of Candida were identified, with C. albicans being the most commonly isolated. Six of the dogs and three cats also had bacteria cultured during the evaluation, some concurrent with their candidal infections. In all of the animals, Candida species UTIs were documented during diagnosis or treatment of other systemic or urinary tract diseases, and the pets had received some nonantifungal drug therapy in the month before diagnosis. Reasons for the drug therapy included endocrinopathy, neoplasia, urogenital disease, and infections.

Candida species organisms are part of the normal flora of dogs and cats. UTI was defined as the isolation of any amount of Candida species by routine microbiological culture. It is thought that conversion of Candida species from commensal organisms to pathogens is secondary to impairment of the normal immune response or host defense mechanism. This was true in all 20 of these cases. Of the five animals in which infection resolved, three did not receive specific antifungal treatment. Specific antimycotic treatment regimens have not been established, but fluconazole may be effective when underlying factors are effectively managed.

COMMENTARY: As in humans, many risk factors predispose to candidal UTIs. Correction of predisposing conditions seems to be the key for management of these infections.

Candida spp. urinary tract infections in 13 dogs and seven cats: predisposing factors, treatment, and outcome. Pressler BM, Vaden SL, Lane IF, Cowgill LD, Dye JA. JAAHA 29:263-270, 2003.