[Demonstration and analysis of immune complexes in rheumatic diseases].

By means of an immunofluorescence technique, immune complexes have been demonstrated in circulating blood leukocytes, in serum and in joint effusions of patients with various rheumatic diseases. Such complexes are present within cell inclusions in about 30% of patients with rheumatoid arthritis (RA). RA patients has immune complexes in serum in 75% of cases and in joint effusions in over 80% of cases. Soluble immune complexes were demonstrated in the serum of about 30% of age-matched patients with degenerative joint disease, while such complexes are present in the serum of only 1.5% of a younger, normal control group. The immune complexes chiefly contain IgG, frequently IgM and only rarely IgA. CO complement component can frequently be demonstrated within such complexes. In RA patients a statistically significant correlation (p less than 0.001) could be established between the presence of soluble immune complexes and erythrocyte sedimentation rate, but no correlation was observed between the presence of such complexes and the Lansbury joint index. The possible pathogenetic role of immune complex clearance by circulating leukocytes in rheumatoid arthritis is discussed.