RESUMO
Objective To detect anti-heterogeneous nuclear ribonucleoprotein A2 (hnRNP A2)/RA33 antibody by ELISA with the purified recombinant hnRNP A2 antigen. Methods The serum of 179 patients with RA, 141 patients with SLE, 97 patients with other diffused rheumatic diseases, 30 patients with seronegative spondyloarthropathies, 10 patients with osteoarthritis, 59 patients with arthralgia/arthritis and 40 controls were detected. In addition, clinical characters and laboratory indexes were compared to study the significance of anti-hnRNP A2/RA33 antibody in RA. Results The sensitivity and specificity of anti-hnRNP A2/RA33 antibody in RA were 36.9% and 87.1%. The positive rates of anti-hnRNP A2/RA33 antibody in SLE, other CTD, seronegative spondyloarthropathies and OA were 19.2%, 7.2%, 6.8% and 0. The positive rate of anti-hnRNP A2/RA33 antibody was 43.3% in early RA patients. Conclusion Detection of anti- hnRNP A2/RA33 antibody with purified recombinant hnRNP A2 antigen is a reliable method for early diagnosis of RA.