The incidence of parathyroid and other antibodies in the sera of patients with idiopathic hypoparathyroidism.

Parathyroid antibodies were demonstrated in 38% of seventy-four patients with idiopathic hypoparathyroidism, 26% of ninety-two patients with idiopathic Addison's disease, 12% of forty-nine patients with Hashimoto's thyroiditis, and in 6% of 245 control patients. A significant percentage of patients with idiopathic hypoparathyroidism also had adrenal, thyroid and/or gastric parietal cell antibodies, even in the absence of diagnosed Addison's disease, thyroid disease, or pernicious anaemia. The antibody(s) against parathyroid tissue are not against parathyroid hormone, and do not cross-react in absorption studies with gastric, thyroid, adrenal, liver or kidney tissue. Species specificity was not investigated. The diagnostic and theoretic considerations are presented.