Clinical significance of combined detection of specific and non-specific autoantibodies in children with SLE

Objective To compare the specificity and sensitivity of anti-Jo1,anti-SSA,anti-SSB,anti-RNP,anti-dsDNA,anti-Sm and antinuclear antibodies(ANA) and investigate the clinical significance of combined detection of the specific autoantibodies in the diagnosis of children with SLE.Methods Sixty children with SLE(SLE group) and 40 children with other autoimmune diseases(control group) were included in this study.Indirect immunofluorescence was used to measure ANA.Western blot was used to measure anti-Jo1,anti-SSA,anti-SSB,anti-RNP,anti-dsDNA,and anti-Sm antibodies.Results The seropositive rates of ANA,anti-dsDNA,anti-RNP,anti-Sm,anti-SSA and anti-SSB antibodies were 96.7%,48.3%,31.7%,30.0%,20.0% and 18.3% respectively in SLE patients,much higher than those of control group(22.5%,10%,7.5%,5.0%,5.0%,and 5.0%,respectively,P0.01).The sensitivity of ANA was higher,but the specificity of ANA was lower than anti-dsDNA,anti-RNP,and anti-Sm antibodies(P0.05).The specificities of anti-dsDNA,anti-RNP,and anti-Sm antibodies were 95.0%,92.5%,95.0% respectively.The level of anti-dsDNA antibody was not correlated with the levels of anti-RNP and anti-Sm antibodies.Combined detection of autoantibodies increased the sensitivity in the diagnosis of children with SLE.Conclusion Anti-dsDNA,anti-RNP,and anti-Sm-antibodies are specific antibodies in the diagnosis of SLE,but these autoantibodies show different sensitivities with highest sensitivity in the detection of anti-dsDNA antibody.Combined detection of autoantibodies may significantly improve the sensitivity in the diagnosis of SLE.