Abstract
In 58 patients treated with radioiodine for hyperthyroidism 5–22 yr previously levels of serum endogenous thyrotropin (TSH) were elevated in about 50% of patients with normal serum protein-bound iodine (PBI) and in about 20% of patients with normal serum PBI treated with thyroid. The levels of serum PBI were normal in about 25% of patients with elevated serum TSH and in about 50% of patients with elevated serum TSH on thyroid. Of 33 patients with elevated serum TSH, 31 did not respond to exogenous TSH. Of 11 euthyroid patients with normal serum PBI and high serum TSH, 4 had developed low serum PBI 3 yr later, whereas others continued normal 19–41 months later. Of 21 patients with low serum PBI and high serum TSH given thyroid, none of those who were euthyroid and all of those who were hypothyroid responded clinically; those who could not be classified clinically as either euthyroid or hypothyroid varied in response. There is good correlation between high levels of endogenous serum TSH and lack of response to exogenous TSH; but often patients have high endogenous serum TSH with a) normal serum PBI, b) euthyroidism remaining for years, or c) no clinical response to thyroid extract.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: The Journal of clinical endocrinology and metabolism
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
