The diagnostic value of anti-cyclic citrullinated peptide antibodies for rheumatoid arthritis in patients with arthropathy

Objectives To investigate the diagnostic value of anti-cyclic citrullinated peptide(anti-CCP) antibodies for rheumatoid arthritis in patients with arthropathy.Methods Serum levels of anti-CCP antibodies were determined by enzyme-linked immunosorbent assay and levels of rheumatoidfactor(RF) were determined by nephelometry in 209 patients with rheumatic diseases.Results 89 of the 209 patients(42.6%) included in this study had RA.The sensitivity and specificity of anti-CCP antibodies for RA was 84.3% and 94.2%;Those for RF was 78.7% and 69.2%,for the presence of either anti-CCP antibodies or RF were 87.6% and 69.2% and for the presence of both anti-CCP antibodies and RF were 74.2% and 94.2% respectively.Of which,the specificity of RF for RA and the presence of either anti-CCP antibodies or RF for RA were significantly lower than anti-CCP antibodies(P0.01).Conclusion With its high sensitivity and specificity,the anti-CCP antibodies assay is a useful test for diagnosing RA.The use of anti-CCP antibodies and RF in combination further increases the diagnostic value for RA but was not statistically significant compared to anti-CCP antibodies.