IGA AND IGM RHEUMATOID FACTORS IN CANINE RHEUMATOID-ARTHRITIS

Serum and synovial fluid IgM and IgA-rheumatoid factors (RF) were meas ured, by ELISA, in groups of dogs with systemic lupus erythematosus, r heumatoid arthritis or osteoarthritis and their levels were compared w ith normal animals. Patients with rheumatoid arthritis had significant ly elevated IgA-RF, particularly those with erosive disease, as did th ose with systemic lupus erythematosus, compared with the other groups. Measurement of IgA-RF may be more useful than IgM-RF for the diagnosi s of rheumatoid arthritis in dogs.