Autoantibodies in systemic sclerosis and fibrosing syndromes: clinical indications and relevance

Systemic sclerosis, or scleroderma, is associated with a variety of autoantibodies, each of them having their own clinical associations. The fibrosing disorders, other than systemic sclerosis, represent a diverse group of diseases with systemic or localized effect and with limited understanding of their pathogenesis. The purpose of this review is to analyze the literature on the clinical usefulness of examining serum autoantibodies in patients with known or suspected scleroderma and fibrosing disorders.

Studies on autoantibodies within the past year highlight their clinical utility in systemic sclerosis. Anticentromere antibodies are most often seen with limited cutaneous involvement and lower frequency of pulmonary fibrosis and lower mortality (despite an increased risk for pulmonary hypertension) compared with anti-Scl-70 and antinucleolar antibodies. Anti-Scl-70 antibodies are associated with diffuse cutaneous involvement, increased frequency of pulmonary fibrosis, and higher mortality. The anti-polymyositis-scleroderma autoantibody is associated with the polymyositis-scleroderma overlap syndrome. Anti-Th/To antibodies are associated with milder skin and systemic involvement but with more severe pulmonary fibrosis and overall worse prognosis. Anti-RNA-polymerase family antibodies and antifibrillarin antibodies are predictive of diffuse cutaneous and systemic involvement and greater mortality. Less specific autoantibodies for systemic sclerosis and limited data on some other autoantibodies limit their clinical utility in patients with systemic sclerosis. For the most part, the association between autoantibodies and fibrosing disorders other than systemic sclerosis remains inconclusive.

Autoantibodies in systemic sclerosis provide important and prognostic information and are useful in defining clinical subsets of the disease. When used appropriately, they can be a useful instrument in the management of scleroderma.