Dry eyes: autoimmunity and relationship to other systemic disease.

Sjögren's syndrome is one of the more common connective tissue diseases, perhaps second in frequency only to rheumatoid arthritis. Autoimmunity in Sjögren's is suggested by its close clinical association with other connective tissue diseases and autoimmune disorders, the dense lymphocytic infiltration of the exocrine glands and the presence of circulating autoantibodies in the majority of cases. Antibodies to the cellular ribonucleoproteins, Ro(SSA) and La(SSB) appear to have clinical significance in this condition, since not only do they identify patients at risk of developing Sjögren's syndrome but also they may have a pathogenetic role in this disease, at least in some of the systemic manifestations.