Thyroid-stimulating antibodies (TSAb) were found in 51 patients (83.6%) with untreated Graves' disease. The mean TSAb index reached the normal level after 6 months of antithyroid drug therapy. In 9 patients (14.8%), TSAb remained persistently positive during and after antithyroid drug therapy, and relapse occurred in all. In 42 patients (68.8%), TSAb indices gradually returned to the normal range after drug treatment was started; in 38% of these, remission was maintained after treatment was stopped, in another 40.5%, relapse occurred when they were TSAb-positive, and the remaining 21.5% relapsed despite return of TSAb indices to the normal range. A positive TSAb index at the end of drug treatment was a useful indicator in predicting subsequent relapse because, with 1 exception, all patients who were still TSAb positive at drug withdrawal relapsed subsequently.

Thyroid-stimulating immunoglobulins (TSI) have been detected by receptor assay in the sera of 43% of patients with ophthalmic Graves' disease. Comparison of the receptor assay studies with thyroid function tests indicated that in several patients the antibodies detected by receptor assay were biologically inactive. In other patients, thyroid function appeared to be under TSI control with hyperthyroidism prevented by autoimmune destruction of the thyroid.

No abstract