Randomised trial of plasma exchange in mild systemic lupus erythematosus.

The effects of intensive plasma exchange on the serological and clinical manifestations of mildly active systemic lupus erythematosus were evaluated in a controlled, double-blind trial. Twenty patients were randomised to receive either six 4-litre plasma exchanges or a seemingly identical control procedure over a 2-week period. Plasma exchange produced significant reductions in serum levels of IgG, IgM, IgA, and circulating immune complexes measured by an 125I-Clq binding assay. These serological measures returned to baseline 4 weeks after plasma exchange without a rebound above baseline values. Antibodies to DNA were reduced immediately after plasma exchange; however, they often returned to pre-treatment levels before the next procedure. No changes in any of the serological measures were observed in the control group. In sixteen of the eighteen patients who completed the clinical trial activity had either remained stable or improved; the frequency and degree of clinical improvement was the same in both plasma exchange and control groups.