Thyroid suppression and the long-acting thyroid stimulator following radioactive iodine therapy for thyrotoxicosis.

Abstract

Summary: Triiodothyronine suppression tests were performed on 47 patients five to 34 months after radioactive‐iodine therapy for thyrotoxicosis. Serum long‐acting thyroid stimulator (LATS) was measured before and at intervals after radioactive iodine. No relationship was found between thyroid suppressibility and serum LATS at the time of the suppression test, nor between suppress/‐bility and the highest LATS litre obtained for each patient during the investigation. Serum LATS was not related to |131 uptake prior to triiodothyronine nor to persistence of toxicity, but there was a slightly higher incidence of detectable LATS in patients whose goitres did not decrease in size following I131 the..