IgA deficiency and systemic lupus erythematosus. Occurrence in an oriental woman with idiopathic epilepsy.

A 25-year-old Oriental woman developed systemic lupus erythematosus during a course of treatment with carbamazepine for long-standing idiopathic epilepsy. Serum IgA was virtually absent, while secretory IgA was quantitated in a small amount in the saliva and gastric juice. Results of immunofluorescent studies on the rectal mucosa and bone marrow did not show any IgA-producing plasma cells. Antibodies against IgA, IgM, milk protein, and bovine serum were detected in the serum. The ability to develop both circulating antibodies and delayed hypersensitivity against test antigens was suppressed. Enumerations of T lymphocytes and IgG and IgM B lymphocytes were within normal limits, whereas IgA B lymphocytes were decreased in number. Results of chromosomal analyses disclosed various abnormalities.