Sjögren Syndrome and the Lung

Abstract

Sjögren syndrome (SS) is a chronic autoimmune disorder of the exocrine glands and extraglandular organs, in which the dryness of the eyes (xerophthalmia) (Figures 23.1a, b, c, d and 23.2a, b, c) and mouth (xerostomia) (Figure 23.3) dominate along with symptoms of polyarthritis (Figure 23.4). It is an autoimmune exocrinopathy with accumulation of lymphocytes and plasma cells; the similar perivascular lymphocytic infitrates could be found in various organs, including the lungs. It can be encountered alone (primary Sjögren syndrome) or in the presence of another autoimmune disorder (60% of cases), most frequently rheumatoid arthritis. Women are more frequently affected than men. Rheumatoid and anti-nuclear factors are positive in a majority of patients; the finding of anti-Ro (SS-A) and anti-La (SS-B) antibodies being specific for SS (Figure 23.5). Despite extensive research, the pathogenesis of SS remains unknown. Certain disturbances of the immune system (i.e., B-cell hyperreactivity and enhanced levels of B cell-activating factor/B-lymphocyte stimulator) probably play a central role in this entity. Whether this is a primary abnormality or the result of predisposing factors remains uncertain.