[New technic for detecting anti-double-stranded DNA antibodies. Value in disseminated lupus erythematosus in...

Two assays for antibodies to double stranded (ds) DNA were compared in children with systemic lupus erythematosus (SLE). An indirect immunofluorescent test using Crithidia luciliae (IF-CL) was more specific but slightly less sensitive than the DNA binding assay (RIA). Detection of antibodies to ds-DNA (anti-ds-DNA) by IF on 3 different trypanosoma (T. brusei, T. equiperdum, and T. musculi) was as specific and as sensitive as IF-CL, but more difficult to read microscopically. No correlation was found between immunoglobulin (Ig) class of circulating anti-ds-DNA and severity of renal disease in SLE. A comparison of serologic and immunohistopathologic (kidney and skin) data in 12 children with SLE showed that immune-complex glomerulonephritis was more frequently encountered when anti-ds-DNA was detected in serum, and that Ig deposits were found only in the skin when anti-ds-DNA could not be detected in serum.