Significance of anti-nucleosome antibodies in systemic lupus erythematosus

Objective To evaluate the diagnostic specificiy and sensitivity of antinucleosome antibodies (AnuA) on systemic lupus erythematosus (SLE),and to analyze the relationship between AnuA and activity of SLE.Methods The enzyme linked immunosorbent assay (ELISA) was used to measure the AnuA in serum of 103 SLE patients,66 patients with other rheumatic diseases (including primary Sjgren syndrome,polymyositis,dermatomyositis and systemic sclerosis) and 30 healthy controls.Results Of the 103 SLE patients,69 9% were seropositive for AnuA.Only 3 0% of 66 control patients were seropositive ( P 0 01);The sensitivity and specificity of AnuA in SLE were 69 9% and 97 9%,respectively.The incidences of renal disorders and skin lesions in AnuA positive SLE were 61 1% and 70 8% respectively,and significantly higher than those of AnuA negative SLE (29 0% and 32 3%, P 0 05);The titer of AnuA was associated with SLEDAI ( r =0 282, P 0 05);There was no significant difference in age,sex and disease duration between positive and negative AnuA of SLE ( P 0 05).The incidences of AnuA in SLE with negative anti dsDNA,Sm,anti deoxyribonucleoprotein antibody (DNP) and anti histone antibody (AHA) were 65 6%,68 0%,63 9% and 64 1%,respectively.Conclusion AnuA is one of the most valuable marker in diagnosis of SLE;AnuA has a close relationship with the activity of SLE;AnuA is valuable in diagnosis of SLE with negative anti dsDNA,Sm,DNP and AHA antibodies.