Significance of combined detection of autoantibodies in systemic lupus erythematosus

Objective To compare the specificity and sensitivity of antibodies against cell membrane associated DNA (cmDNA)、 nucleosome (AnuA)、 double stranded DNA (dsDNA)、 deoxyribonucleoprotein (DNP) and antinuclear antibodies (ANA) in systemic lupus erythematosus (SLE). To analyze the relationship between these auto-antibodies in SLE. Methods One hundred and twenty five SLE patients and 118 other rheumatic diseases patients were studied. The latter included primary Sj?觟gren syndrome, ploymyositis, dermatomyositis, rheumatoid arthritis, osteoarthritis and systemic sclerosis. Indirect immunofluorescence was used to measure the anti-cmDNA antibodies and ANA. The enzyme-linked immunosorbent assay (ELISA) was used to measure the AnuA. Anti-DNP antibodies were detected by latex agglutination text and anti-dsDNA antibodies were detected by colloidal gold-technique. Results The seropositive rates of AnuA、 anti-cmDNA、 DNP、 dsDNA antibodies and ANA were 68%、 38.4%、 51.2%、 49.6% and 95.2% respectively in SLE patients. They were much higher than those of control groups (P0.001). The sensitivities of ANA and AnuA were higher than those of anti-DNP、 cmDNA and dsDNA antibodies in SLE(P0.05). Specificities of AnuA、anti-DNP、 cmDNA and dsDNA antibodies in SLE were higher than that of ANA. Combination of AnuA and anti-DNP antibodies or anti-dsDNA antibodies increased the sensitivity of autoantibodies in the diagnosis of SLE. Conclusion AnuA、 anti-cmDNA、 DNP and dsDNA antibodies are specific antibodies for diagnosis of SLE. Combination of AnuA and anti-DNP or anti-dsDNA antibodies can significantly improve the sensitivity of these autoantibodies in the diagnosis of SLE.