Abstract
We described here a 27-year-old patient with selective IgA deficiency associated with three organ-specific autoimmune diseases; myasthenia gravis, autoimmune hemolytic anemia and autoimmune thyroiditis. This is the first report which documents so many associated autoimmune diseases in a patient with immune deficiency of this type, although the association of the disease with various autoimmune diseases has been described.
Serum IgA levels were less than 5mg/dl in the patient, and serum anti-IgA antibodies were detected at high titer. Furthermore, we could detect IgG, IgA, IgM and complement components on patient's erythrocytes by direct Coombs' test, and the presence of IgA on the erythrocytes were also confirmed by enzyme-linked immunosorbent assay using the eluate from erythrocytes.
Following to thymectomy undertaken for the management of myasthenia gravis, septicemia and hemolytic attack had developed in the patient. These complications were successfully treated with antibiotics and prednisolone, 60mg daily. No definite increase in serum IgA levels was observed during the treatment, although both myasthenia gravis and autoimmune hemolytic anemia were improved remarkably. Pathologically, patient's thymus was moderately involuted and contained lymphoid follicles. The thymectomy was considered to be effective for the management of myasthenia gravis in the patient based on 30 month-observation after the thymectomy.
The patient's salivary IgA were detected, but its concentration was low as compared with that of healthy controls. Surface IgA-bearing B lymphocytes were detected in the peripheral blood, whereas intracytoplasmic IgA synthesis was not demonstrated in the peripheral blood lymphocytes cultured with PWM.
We believe that this case report provides further considerations, clinically and immunologically, for the understanding of selective IgA deficiency and its associated diseases.
