Relationship between anti-DNA antibodies complement consumption and circulating immune complexes in systemic lupus erythematosus.

Eighty-nine sera from nineteen patients with systemic lupus erythematosus (SLE) have been studied to determine the relationship between levels of DNA-binding activity, complement consumption and evidence of circulating immune complexes. There was a good correlation between the height of DNA binding, a rising C3i and a reciprocal fall in C3, C4 and CH50 levels. These latter measurements provided useful supplemental information when studied serially. There was a good correlation between the results of the various methods used for the detection of circulating immune complexes, and these were found in almost half the sera with DNA binding over 70%. It is concluded that serial studied of DNA binding, complement levels, and direct tests for immune complexes, may provide valuable information in the management of patients with SLE.