[Thyroliberin test after treatment of thyrotoxicosis]

The thyroliberin (TRH) test was used for examining 343 persons. The substance was injected intravenously in a dose of 200 micrograms, with thyrotropin (TTH) being studied by radioimmunoassay before and 30 minutes after stimulation. The test was performed over time after operation and drug treatment of diffuse toxic goiter in the course of 1-3 years of follow up. The test was ascertained to be informative for thyrotoxicosis. During mercazolyl treatment the increase in the test estimates was slow in progress. After the attainment of euthyrosis these estimates were on the average below normal (for 3-6 months). The pituitary reserves of TTH were not recovered until one year after operation and drug treatment. If thyrotoxicosis recurred, the test estimates dramatically fell again, but exceeded normal in the development of hypothyrosis that mostly ran a latent and subclinical course. The test is of importance for the diagnosis of thyrotoxicosis and appraisal of the time course of the health status after drug treatment, since it helps individualize the treatment and identify the relapse or excessive suppression of thyroid function. Repeated making of the TRH test after strumectomy enables making early diagnosis and prediction of hyperthyrosis. After mercazolyl treatment hypothyrosis is commonly reversible whereas postoperative hypothyrosis normally progresses, thereby requiring substitution therapy.