Evaluating the performance of four anti-dsDNA antibody detection methods.

ObjectiveTo evaluate the concordance of four anti-dsDNA antibody detection methods-Crithidia luciliae indirect immunofluorescence test (CLIFT), enzyme-linked immunosorbent assay (ELISA), acridine ester direct chemiluminescence immunoassay (CLIA), and digital liquid chip method (DLCM)-and to assess their diagnostic efficacy in systemic lupus erythematosus (SLE) patients.MethodsA total of 285 serum samples were collected, including 170 SLE patients, 39 with non-SLE autoimmune diseases (AIDs), 28 with non-AIDs, and 48 undiagnosed cases. The concordance and diagnostic performance of anti-dsDNA antibody methods were analyzed.ResultsThe diagnostic performance showed that DLCM exhibited the highest sensitivity (86.87%), while CLIA demonstrated the highest specificity (94.03%). The area under the receiver operating characteristic (ROC) curve (AUC) was ranked as CLIFT < ELISA < CLIA < DLCM (AUC = 0.938). Anti-dsDNA antibodies detected by both CLIFT and DLCM correlated well with the SLE disease activity index (SLEDAI), while CLIFT and CLIA were significantly correlated with lupus nephritis. Utilizing ROC curve-derived cut-off values, the overall concordance of CLIFT and other methods ranged from 80.14% to 82.58% (kappa > 0.6, P < 0.001), and the concordance between quantitative methods ranged from 89.55% to 91.29% (kappa > 0.8, P < 0.001).ConclusionCLIFT, ELISA, CLIA, and DLCM all showed impressive diagnostic efficacy in detecting anti-dsDNA antibodies. CLIFT shows a strong correlation with SLE activity and lupus nephritis. DLCM, a relatively new method, also showed excellent performance and could be integrated into clinical laboratory workflows for anti-dsDNA antibody testing.