Autoantibodies in scleroderma and their association with the clinical profile of the disease. A study of 66 patients from southern Brazil.

BACKGROUND Scleroderma is a fairly rare connective tissue disease whose autoantibody profile is associated with different clinical manifestations. The prevalence of autoantibodies in scleroderma is influenced by race and genetics. OBJECTIVE To study the prevalence of anti-Scl-70, anti-centromere (ACA) and anti-U1-RNP antibodies in patients with scleroderma in southern Brazil and verify their association with clinical manifestations of the disease. METHODS A retrospective study involving 66 patients with scleroderma for the presence of anti-Scl-70, anti-centromere and anti-U1-RNP and of clinical manifestations such as Raynaud's phenomenon, digital micro scars, digital necrosis, telangiectasias, calcinosis, pulmonary fibrosis, pleuritis, pericarditis, cardiomyopathy, arthralgia and arthritis, skin sclerosis, joint contractures, tendon friction rubs, pulmonary hypertension, esophageal disorders and renal crisis. RESULTS The prevalence of anti-Scl-70 was 17.8% , that of ACA was 33.3% and the prevalence of U1 RNP was 11.8%. Anti-Scl-70 was associated with the diffuse form of the disease (p = 0.015), presence of cardiomyopathies (p = 0.016) and digital micro scars (p = 0.05). Anti-centromere was more common in the limited form, although it was not statistically significant, and had a protective role associated with cardiomyopathies (p = 0.005). Anti-U1-RNP was more common in the overlap forms (p = 0.0004). CONCLUSION The prevalence and profile of clinical associations of autoantibodies in Brazilian patients with scleroderma are similar to those found in the literature.