Diagnostic value of anti-cyclic citrullinated peptide antibody in patients with rheumatoid arthritis

Objective To investigate the clinical value of anti-cyclic citrullinated peptide antibody(anti-CCP)in the diagnosis of rheumatoid arthritis(RA).Methods 155 patients with RA(RA group),178 patients with non-RA(non-RA group)and 100 healthy controls(healthy control group)were involved in the investigation.Enzyme linked immunosorbent assay(ELISA)was applied to detecting serum anti-CCP,and latex-enhanced immunoturbidimetry was employed to determine rheumatoid factor(RF).The sensitivity,specificity,positive and negative predictive values were compared between anti-CCP and RF.Results The sensitivity of anti-CCP antibody and RF for RA was 63.2% and 59.1%,and specificity was 95.0% and 81.6%,respectively.Positive predictive value was 87.5% and 64.3%,respectively.Negative predictive value was 82.2% and 58.2%,respectively.Anti-CCP antibody was positive in 34.9% of RF negative patients with RA.Anti-CCP antibody showed a correlation with the radiographic joint damage rate.Anti-CCP positive patients with RA had increased arthrocele and serum CRP concentration compared to anti-CCP negative patients with RA.However,no correlation was found between anti-CCP antibody and DAS28 score.Conclusion In RA patients,anti-CCP2 antibody is of higher diagnostic value than RF.Moreover,it is associated with radiological joint damage.