Retrospective evaluation of the efficacy of fluconazole for the treatment of coccidioidomycosis in dogs: 49 cases (2015-2020)

Abstract

Objective: To characterize the clinical course and therapeutic response in dogs with coccidioidomycosis treated with fluconazole.

Animals: 49 client-owned dogs with coccidioidomycosis that were treated with fluconazole and had ≥ 2 follow-up examinations.

Procedures: Medical records were retrospectively searched to identify dogs in which coccidioidomycosis was diagnosed between January 2015 and May 2020. Data recorded from each dog included signalment, clinical signs, diagnostic test results, and treatment.

Results: Dogs were treated with fluconazole at a median initial dosage of 19.7 mg/kg/d. Median treatment duration was 298.5 days, with 26 of the 49 dogs completing treatment during the study period. Respiratory signs, lethargy, and hyporexia were the most common clinical signs. Frequency of lethargy decreased after 30 days, whereas frequency of hyporexia and respiratory signs decreased after 90 days. Median IgG titer at diagnosis was 1:32 and was significantly decreased, compared with baseline titer, at all recheck intervals after 90 days. Hyperglobulinemia, monocytosis, and neutrophilia were the most common clinicopathologic abnormalities. Hyperglobulinemia resolved within 30 days, neutrophilia resolved within 90 days, and monocytosis resolved after 180 days.

Clinical relevance: Improvements in clinical signs, titers, and clinicopathologic abnormalities were observed after initiation of treatment with fluconazole. Improvement began as early as the first 3 months of treatment, but some variables did not resolve until after 6 to 9 months of treatment. This information provides clinical guidance and describes expectations when prescribing fluconazole to treat coccidioidomycosis in dogs.