• Two patients with systemic lupus erythematosus (SLE) had pericardial tamponade. The pericardial fluid from both patients contained "mixed" type cryoglobulins consisting of IgG, IgM, and C1q. There was a selective concentration of antinuclear antibodies in the pericardial fluid cryoglobulin of one patient. Pericardial fluid from the same patient contained immune complexes. Anti-DNA antibodies were found in the serum, pericardial fluid, and pericardial fluid cryoprotein. Immune complexes isolated from the pericardial fluid by polyethylene glycol precipitation contained antinuclear antibodies including anti-DNA antibodies. Immune complexes may be important in the pathogenesis of pericarditis in SLE.
(Arch Intern Med 140:112-114, 1980)