Transient Neonatal Hypothyroidism Due to Maternal Immunoglobulins that Inhibit Thyrotropin-Binding and Post-Receptor Processes

Abstract

Transient neonatal hypothyroidism was found in a daughter of a 25-yr-old mother, who was receiving treatment for primary hypothyroidism due to Hashimoto's thyroiditis. During the neonatal period the infant had antithyroid microsomal and antithyroglobulin antibodies and TSH-receptor antibodies. The daughter recovered spontaneously from the hypothyroid state and the antithyroid antibodies disappeared from her serum. The mother's serum contained the same antibodies, and immunoglobulin G (IgG) from maternal serum blocked TSH binding to its receptors, TSH-stimulated cAMP responses, and cAMP-stimulated iodine uptake and organification in cultured thyroid cells. The latter finding suggests that the IgG had a postreceptor locus of action as well as inhibiting TSH binding to its receptor. The presence of such IgGs might have induced hypothyroidism both in the mother and in the daughter.

Immune Mechanisms In Graves' Disease

“…In the past several years it has become evident that some patients may have serum anti-TSH receptor antibodies that inhibit or block TSH stimulated events (359)(360)(361)(362)(363)(364)(365)(366)(367)(368)(369). In 1960 Sutherland et al (369) described children who were hypothyroid and who had familial nongoitrous disease.…”

Technetium 99m pertechnetate thyroid scintigraphy: congenital hypothyroid screening

“…that which resolves without therapy, has several possible etiologies [5]. Maternal or fetal circulating antithyroid antibodies have been implicated in some cases [10]. Many cases have been related to maternal ingestion of antithyroid medication or maternal or neonatal iodine excess.…”

Production of Thyroid Stimulation Blocking Antibody Without TSH Receptor Binding Activity in Rabbits With Experimental Autoimmune Thyroiditis

“…The presence of TSBAb activity in autoimmune thyroiditis with TBII activity have been reported (Konishi et al 1983;Takasu et al 1984;Arikawa et al 1985;Ginsberg et al 1986;Mori et al 1987;Cho et al 1989;Yoshikawa et al 1989;Tamaki et al 1990). It is generally believed that the TBII positive type TSBAb may block TSH binding to TSH receptors in spite of the innocent action of TSBAb itself and cause TSH unresponsiveness and hypothyroidism.…”

“…Metab. 59: 142-146 (1984) Tamaki, H., N. Amino, M. Kimura, Y. Hidaka, K. Takeoka, K. Miyai:The presence of autoantibodies which block the stimulatory effect of TSH on thyroid have been reported in autoimmune thyroiditis(Konishi, Iida, Endo, Misaki, Nohara, Matsuura, Mori and Torizuka 1983;Takasu, Mori, Koizumi, Takeuchi and Yamada 1984;Arikawa, Ichikawa, Yoshida, Shinozawa, Homma, Momotani and Ito 1985; Ginsberg, Wol- fish, Rafter, von Westarp and Ehrlich 1986; Mori, Akamizu, Horm. metab.…”