The role of anti-cyclic citrullinated peptide antibodies in predicting progression of palindromic rheumatism to rheumatoid arthritis

OBJECTIVE: To determine whether the presence of anti-cyclic citrullinated peptide (anti-CCP) antibodies at presentation is of prognostic value in patients with palindromic arthritis. METHODS: Stored sera, taken around the time of presentation from patients with palindromic arthritis, where available, were assessed for anti-CCP antibodies, and results were correlated with subsequent clinical outcome. RESULTS:Twenty-nine of 61 patients had progressed to rheumatoid arthritis after a mean followup of 5.4 years; 83% of these had had anti-CCP antibodies in their baseline sera. CONCLUSION: The sensitivity/specificity and likelihood ratios for CCP antibodies were better than rheumatoid factor in predicting outcome.