Clinical presentation, diagnostic findings, and outcome in dogs with presumptive primary and reactive immune-mediated polyarthritis in France

Limited data exist regarding immune-mediated polyarthritis in dogs, particularly regarding reactive immune-mediated polyarthritis. The aim of this study was to describe the clinical presentations, the diagnostic findings, and the outcome of dogs diagnosed with presumptive primary and reactive immune-mediated polyarthritis in France, and to evaluate potential biomarkers for assessing treatment response. Medical records were retrospectively reviewed for dogs diagnosed with immune-mediated polyarthritis between June 2004 and January 2020. Fifty-eight dogs were included, of which 43 diagnosed with primary and 15 with reactive immune-mediated polyarthritis. Associated diseases in dogs with reactive immune-mediated polyarthritis included leishmaniosis (7), digestive disorders (3), eosinophilic bronchopneumopathy (3), bacterial infection (1), and gossypiboma (1). Overall, dogs showed a combination of joint swelling, pain, or heat. Anaemia (30 %), leucocytosis (47 %), high serum CRP (90 %) and low serum albumin (61 %) concentrations were the most frequent bloodwork abnormalities. Most dogs (74 %) experiencing complete clinical remission, and the mean time to remission was 37 days. Serum albumin, total proteins and globulins concentrations appeared as potential predictors for the time to remission. Clinical presentation and diagnostic features are not specific in dogs with immune-mediated polyarthritis. Overall, most dogs achieve clinical remission, but the time to achieve remission may be long. Serum albumin, total proteins and globulins concentrations may be predictors for the time to remission.