[The effect of treatment on circulating immune complexes in rheumatoid arthritis (author's transl)].

Immune complexes were demonstrated by leucocyte phagocytosis assay in 37 of 55 patients with rheumatoid arthritis. After treatment with gold salts, penicillamine, alpha-mercaptopropionylglycine, immunosuppressive agents or levamisole a substantial fall or elimination of demonstrable circulating immune complexes occurred. In-vitro studies revealed that gold salts in therapeutic concentrations inhibited the phagocytosis of immune complexes, while other drugs - penicillamine, levamisole and all anti-inflammatory agents including corticosteroids - lack this effect. The reduction in circulating immune complexes under basic therapy may be due to a beneficial effect of these agents on the disease process itself. This test may, therefore, be of value in assessing the efficacy of drug treatment.