Systemic lupus erythematosus.

Systemic lupus erythematosus is an autoimmune disease of unresolved cause afflicting predominantly women in their childbearing years. Speculation exists as to the relative roles of viruses, histocompatibility loci such as HLA-DR3, and estrogenmediated decreases in suppressor cell function. Whatever the cause of familial tendency, the disease results in a pathologic hyperactivity of the B-lymphocyte population and a subsequent production of autoantibodies. This hyperactivity may reflect a primary B-cell defect or a deficiency of regulatory cells.