Detection of islet cell surface antibody in the thyroid disease and systemic lupus erythematosus

Islet cell surface antibody (ICSA) was examined on sera from the patients of Graves' disease, Hashimoto's thyroiditis and systemic lupus erythematosus (SLE). Five out of 22 patients (23%) of Graves' disease, 8 out of 32 patients (25%) of Hashimoto's thyroiditis and none of SLE patients and healthy subjects were proved to have ICSA. The incidence of ICSA was associated with the duration of the disease in Graves' disease patients (P<0.01), but had no correlation with sex, age of onset or microsome antibody (MCHA) titer. Antilymphocytotoxic antibody (ALA) was examined on sera from ICSA positive patients with high MCHA titer and SLE patients. The incidence of ALA of the former ((%) was significantly lower than that of the latter (55%) (P<0.05). These findings may suggest that plural antibodies against different endocrine organs are produced in a part of the thyroid disease and that the mechanisms of immunological disorders of such patients are different from those of SLE.