The Prevalence of Thyroid-Stimulating Antibodies in Goitrous Disease Assessed by Cytochemical Section Bioassay*

Abstract

Thyroid-stimulating antibodies (TSAb) were detectableusing a highly sensitive cytochemical section bioassayin plasma from all 56 hyperthyroid patients studied, includingthose who had either diffuse hyperplasia or nodular goiters. Themaximum dilution at which TSAb was detectable ranged from10⁻²–10⁻⁶. Six of these patients had scintigraphic evidence ofsingle functioning nodules, and, surprisingly, TSAb was presentin all. Of 27 patients who had nontoxic goiter, 14 (52%) hadpositive titers for TSAb ranging from 10⁻²–10⁻⁴. The mean serum T₃ value in nontoxic goitrous patients who had TSAb wassignificantly higher than that in subjects in whom TSAb wasabsent; in contrast, mean serum T₄ values were not significantlydifferent in those two groups. It is concluded that idiopathicnontoxic goiter, toxic nodular goiter with functioning nodules(Plummer’s disease), and toxic diffuse goiter (Graves’ disease)share, in part, a common pathogenesis.