Relationship between potency of blocking type thyrotropin-binding inhibitor immunoglobulin in three women with primary myxedema and thyroid function of their neonates.

Abstract

Three neonates born to three mothers with primary myxedema who have thyrotropin-binding inhibitor immunoglobulin (TBII) were continually examined after birth.One neonate showed a high TSH level in mass-screening for congenital hypothyroidism and developed transient hypothyroidism.Her TBII disappeared at 114 days of age, and she remained euthyroid after discontinuation of thyroxin replacement at 146 days of age. The other two neonates were euthyroid, though they had positive TBII.In three mothers, the doses of IgGs that inhibited 125I-TSH binding to the level of 50% were compared. The potency of IgG from the mother whose neonate developed hypothyroidism was stronger than that of IgG from the other two mothers. And the elevation of cAMP induced by bovine TSH in suspension culture with porcine thyroid follicles was significantly reduced in the presence of IgG from the three mothers when compared with normal IgG. The thyroid-stimulation blocking activity was more potent in the mother whose neonate developed hypothyroidism than in the other two mothers. This study suggests that the thyroid function of neonates born to primary myxedema with blocking type TBII is influenced by the potency of TSH-binding inhibitor and thyroid-stimulation blocking activity of the mother.

A Patient with Graves' Disease who Developed Hypothyroidism Associated with Thyroid Stimulation Blocking Immunoglobulin during Anti-thyroid Drug Therapy.

“…In a separate investigation, TBII with TSBI was found in patients with primary myxedema (Endo et al, 1978), and led to transient neonatal hypothyroidism by placental transmission (Matsuura et al, 1980;Inomata et al, 1986). When this patient developed hypothyroidism, her IgG showed characteristics of TBII and TSBI that were similar to IgG found in cases with primary myxedema.…”

The Prediction of thyroid Function in Infants Born to Mothers with Chronic Thyroiditis.

“…1.3 to 2.1 U/ml standard TBII-serum). This (Ishihara, et al, 1985, Inomata, et al, 1986, Tamaki, et al, 1989. The 50% inhibition of TSH-induced cAMP accumulation was obtained at 3000-fold dilution in M-1 who gave birth to cases 1 and 2, but it was obtained at only 50-fold dilution in M-3 who gave birth to a euthyroid infant (Case 5).…”

Transient Hypothyroidism in Infants Born to Mothers with Chronic Thyroiditis-A Nationwide Study of Twenty-three Cases.

“…1985 ;Yokota, et al, 1985;Kanaya, et al, 1985;Mashimo, et al, 1985;Inomata, et al, 1986) since then, the clinical features as well as the prognosis of each case varied a great deal. Although most infants recovered completely, some were physically, mentally or emotionally retarded in spite of intensive treatment during the newborn period (sutherland, et al, 1960;Goldsmith, et al, 1973).…”