Canine immune-mediated polyarthritis: clinical and laboratory findings in 83 cases in western Canada (1991-2001)

A hospital-based, case-control study was used to describe clinical and laboratory findings in 83 dogs diagnosed with noninfectious, nonerosive, immune-mediated polyarthritis (IMPA) in western Canada. Case medical records were reviewed. Cases were analyzed as total IMPA cases and as subgroups [breed, systemic lupus erythematosus (SLE), reactive, and idiopathic] and compared with the general canine hospital population. Dogs with IMPA differed in age (P = 0.004) and weight (P = 0.01) from other hospital admissions. Idiopathic IMPA cases were older (4-10 y; P < 0.05), compared with the general canine hospital population, and their common laboratory abnormalities included the following: leukocytosis, nonregenerative anemia, increased alkaline phosphatase, and hypoalbuminemia. The SLE cases were seen more often in summer and fall (P = 0.04), raising concern of an undiagnosed etiologic agent. The hock joint appeared to be the most reliable for diagnosis of IMPA, and arthrocentesis of both hock joints may aid in case identification.