Medical treatment options for perianal fistula in dogs

Abstract

BACKGROUND: Perianal fistulae are a common, recurrent and painful disease in dogs, particularly in German shepherd dogs, and significantly affect the quality-of-life for both the animal and its owner. HYPOTHESIS/OBJECTIVES: Management remains challenging and there is a lack of high-quality evidence for efficacy of the different medical treatment options. The aim of this article was to provide clinicians with a framework for decision-making. MATERIALS AND METHODS: A literature review was conducted on medical treatment studies, utilising the Strength of Recommendation Taxonomy (SoRT) for grading evidence quality. PubMed, Scopus and EBSCOhost Research Databases (CAB and Medline) databases were searched for relevant publications between 1980 and August 2024, using the keywords: dog and perianal or anal and fistula, ulcer or furunculosis. Recommendations were based on authors' consensus and organised around four relevant clinical questions. RESULTS: Twenty clinical treatment studies were included with evidence assessed and recommendations presented for ciclosporin (alone and in combination with ketoconazole), tacrolimus, prednisolone, azathioprine, photobiomodulation, stem cells, oclacitinib, mycophenolate mofetil, dietary modifications and for surgery following medical treatment. Ciclosporin is recommended as the first-line treatment option with clinical response likely to be dependent on time and dose. In cases where ciclosporin fails, alternatives include the combination of prednisolone and tacrolimus or surgical intervention following medical treatment. CONCLUSIONS AND CLINICAL RELEVANCE: This is the first literature review using SoRT criteria for the treatment of canine perianal fistulae. High-quality studies with precise and detailed criteria are needed to improve treatment recommendations and outcomes.