Abstract:

Objective To investigate the roles of anti-nuclear antibody （ANA） and other related parameters for the diagnosis of different autoimmune diseases （AID）. Methods A total of 1 905 AID patients were enrolled and studied retrospectively. ANA and anti-extractable nuclear antigen （ENA）,anti-double-stranded DNA （ds-DNA） and anti-nucleosome （Nuc） antibodies were determined. Totally,4 433 healthy subjects were enrolled for ANA karyotypes and titer distribution. Th. Results were collected and analyzed by t test and non-parameter test,Spearman correlation analysis was used,and receiver operating characteristic （ROC） curve was used for evaluating diagnostic efficiency. Results The major patterns in primary biliary cirrhosis （PBC） and autoimmune hepatitis （AIH） were mixed type and cytoplasmic granules for ANA karyotypes,but there were homogenous, speckled and mixed patterns in other AID as well. Patients with ankylosing spondylitis （AS）,rheumatoid arthritis （RA） and inflammatory myositis （IM） had titer （median）≤1∶160,and other AID patients had high titer（≥1∶320）. For systemic lupus erythematosus （SLE） patients,the titers of ANA were positively correlated with anti-ds-DNA antibody （r=0.394,P<0.01）. In adult SLE group （898 cases）,the proportion of females,ANA and anti-ds-DNA antibody,anti-Nuc antibody and anti-uracil-1 low molecular weight ribonucleoprotein（U1RNP） antibody positive rates were higher than those in pediatric SLE group （103 cases,P<0.01）. When the titer was 1∶80,the sensitivity was 97.1%,and the specificity was 38.7%. When the titer was 1∶160,the sensitivity was 80.1%,and the specificity was 80.8%.Conclusions The positive rates and titers of ANA have difference among patients with different AID. Some special karyotype analysis can provide a reference for the diagnosis of AID. ANA titer is positively correlated with anti-ds-DNA antibody in patients with SLE. The titers of ANA （1∶80 and 1∶160）could be used for health examination screening and AID diagnosis.

Key words: Anti-nuclear antibody, Autoimmune disease, Healthy subject, Pediatric systemic lupus erythematosus