Value of thyroid-stimulating-antibody determinations in predicting short-term thyrotoxic relapse in Graves' disease

Thirty consecutive patients with hyperthyroid Graves' disease received a 6-month course of antithyroid drugs. Sixteen patients relapsed within 6 months of the withdrawal of antithyroid therapy. All patients with high levels of thyroid-stimulating antibodies (TSAb) at the time of drug withdrawal relapsed within 2 months of discontinuing the antithyroid treatment while all patients with low or undetectable TSAb activity at the time of drug withdrawal remained in remission. It was not possible to predict the disease course in patients who had intermediate levels of TSAb when antithyroid therapy was stopped.