Double-stranded DNA antibodies: a comparison of four methods of detection.

Abstract

Antinuclear antibody (ANA) positive systemic lupus erythematosus (SLE) sera (34 samples) were simultaneously tested for antibodies to double-stranded DNA (dsDNA) using Farr, hemagglutination, Crithidia luciliae (CL) kinetoplast fluorescence and human metaphase chromosome fluorescence assays. Significant correlation (P < 0.05) was found between the Farr and CL assays, with the 2 fluorescence tests (CL and metaphase) displaying the greatest degree of association (P = 0.00001). No correlation could be demonstrated between the hemagglutination test and any of the other 3 assays. Sera (691 samples) from patients with a range of provisional rheumatological diagnoses were prospectively analyzed for dsDNA antibodies using Farr and metaphase assays. A correlation coefficient of 0.84 was obtained between the 2 assays. The metaphase assay provides comparable results to other more established assays, and because it is simple, reliable and sensitive, it should be seriously considered for routine use in testing for dsDNA antibodies.