Diagnostic value of anti-CCP antibody and IgG-Rf in rheumatoid arthritis

Abstract

Objective To explore the clinical value of the combined detection of anti - cyclic Cit-rullinated peptide(anti-CCP) antibody and rheumatoid factor (Rf) in the diagnosis of rheumatoid arthritis (RA). Methods Anti- CCP antibody was measured by ELISA and IgG- Rf were detected by rate nephe-lometry. Results In 68 patients with RA the sensitivity for anti - CCP antibody and IgG - Rf were 57.4%and 69.1% respectively. In 61 non-RA patients the speciality for anti -CCP was 97. 6% ,and for IgG- Rfwas 89.7%. If combined the detection of anti -CCP antibody and IgG -Rf,the sensitivity reached 30.9% ,the speciality reached 100%. In 21 patients with negative IgG - Rf 6 cases were anti - CCP antibody positive, the positive rate was 28.6%. In 47 patients with positive IgG - Rf 42 cases were anti - CCP antibody positive, the positive rate was 89.4%. Conclusions Anti -CCP antibody could improve the accuracy of early diagnosis of RA. The combined detection of anti - CCP antibody and IgG - Rf could reduce the misdiagnosis of RA. Mean-time the speciality and the positive predicative value could be raised. Key words: Anti -cyclic citrullinated peptide antibody; Rheumatoid factor; Rheumatoid arthritis