Diagnostic value of synovial fluid anti-cyclic citrullinated peptide antibody for rheumatoid arthritis

Early and accurate diagnosis and treatment of rheumatoid arthritis (RA) improves disease outcome. Anti-cyclic citrullinated peptide antibody (anti-CCP) which is highly specific for RA is produced locally from inflamed synovium. The present study was designed to assess the diagnostic performance of synovial fluid anti-CCP (sf-CCP) for RA. A total of 128 patients consisted of 37 RA confirmed by the American College of Rheumatology revised criteria, 91 non-RA (50 non-RA inflammatory arthritis and 41 osteoarthritis) entered the study. Serum anti-CCP (sm-CCP) and Sf-CCP were measured by the ELISA method. Receiver operating characteristics curves were constructed to determine the optimal cutoff point levels for sf-CCP and sm-CCP to discriminate RA from non-RA. Diagnostic characteristics of both variables were determined by comparison of RA patients with non-RA controls. Mean levels of sf-CCP and sm-CCP were significantly higher in RA than in non-RA ( P