Comparison of three assays for anti-DNA with three assays for the measurement of the role of complement in systemic lupus erythematosus in adolescents.

Three assays for anti-DNA antibody were compared simultaneously with assays for Clq binding, C3 concentration, and the activation of C3 (C3c,d) on blood of children with systemic lupus erythematosus. The Farr assay and the Millipore filter assay for anti-DNA were abnormal most frequently, followed by the assay for C3c,d. Positive assays for C3c,d were closely associated with abnormal Millipore filter assays. Clq binding was elevated in 42% of samples, but was not associated with any other abnormality. The hemagglutination assay for anti-DNA and the C3 concentrations were the least frequently abnormal.