Significance of detection of the autoantibodies in patients with rheumatoid Arthritis

Objective To explore the sensitivity of antibodies against RF,APF,AKA,anti-CCP in rheumatoid arthritis (RA) and analyze the relationship between these autoantibodies in RA.Methods Five hundreds of RA patients were studied.Immunoturbidmetry was used to measure the RF-IgM.The enzyme-linked immunosorbent assay (ELISA) was used to measure the HRF-IgG,HRF-IgA and anti-CCP.Indirect immunofluorescence was used to measure the APF and AKA.Results The seropositive rates of RF-IgM,anti-CCP,APF,HRF-IgG,AKA and HRF-IgA were 78.0%,70.8%,51.8%,48.4%,45.0% and 20.0% respectively.RF-IgM could not be detected in 110 patients while the seropositive rates of anti-CCP,APF,AKA,HRF-IgG and HRF-IgA were 41.8%,27.3%,22.7%,15.5% and 1.8% respectively.Anti-CCP could not be detected in 146 patients while the seropositive rates of RF-IgM,HRF-IgG,APF,AKA and HRF-IgA were 56.8%,24.7%,16.4%,8.9% and 7.5% respectively.The combined sensitivities of RF-IgM anti-CCP and APF were higher than others.The seropositive rates were 88.6%.Conclusions RF-IgM and anti-CCP are sensitive antibodies for diagnosis of RA.Combinations RF-IgM with anti-CCP can significantly improve the sensitivity of diagnosis of RA. Key words: Arthritis,rheumatoid/IM; Antibodies/ME; Immunoglobulin M/ME; Rheumatoid factor/ME; Keratins/ME