Immune disorders are characterized by development of autoantibodies. Autoantibodies, particularly antinuclear antibodies, are detected in the majority of patients with connective tissue diseases such as systemic lupus erythematosus and scleroderma. Recent reports have described persons with silicone implants who have developed scleroderma and systemic lupus erythematosus. Since autoantibodies are suspected to play an important role in the pathogenesis of the connective tissue disease, the nature of the autoantibodies produced in patients with silicone-associated rheumatic disease is important to understand. A review of the English literature and abstracts from the 1992 American College of Rheumatology meeting showed that immunofluorescent testing for antinuclear antibody was positive in a wide range (7% to 68%) of patients with silicone implants. When examining only those patients with silicone implants and clinical evidence of connective tissue disease, the proportion of patients with a positive immunofluorescent test was less than commonly found in a series of patients with idiopathic connective tissue disease. Sensitive testing by Western blot technique revealed autoantibodies in 10% of patients with silicone implants and negative immunofluorescent test results. Patients with silicone implants and scleroderma-like illness were characterized by anticentromere and anti-PM-Scl antibodies, whereas patients with silicone implants and SLE or undifferentiated connective tissue disease were characterized by antibodies to small nuclear ribonucleoproteins, specifically B'/B polypeptide. In addition, antibodies to a high molecular weight protein have been discovered by Western blot in more than 50% of persons with silicone implants. Differences in autoantibody production between patients with silicone-associated rheumatic disease and patients with idiopathic rheumatic disease may be a distinguishing feature. Further characterization of these autoantibodies is needed.