title: Usefulness and limitations of thyrotropin measurements as a first-line test for follow-up of Graves' patients.
abstract: We evaluated the usefulness of sensitive thyrotrophin hormone (TSH) measurements in determining the thyroid status in the follow-up of Graves' patients undergoing medical treatment with thionamides. Out of a total of 186 serum samples tested, TSH levels were suppressed in 123 (66.1%), normal in 32 (17.2%) and elevated in 31 (16.7%) cases. Total T4, or T3 or both were elevated only in 97 (74.8%) cases of TSH-suppressed patients, indicating that TSH is less discriminatory as a first-line test for patients under treatment due to the hypothalamic-pituitary lag period. No comparisons with free T4 or free T3 were done in this study. Both total T4 (120 +/- 28 nmol/l) and TBII (23 +/- 21%) levels were significantly greater (p < 0.02) in the euthyroid group with suppressed TSH. This may suggest that persistence of a thyrotoxic state may still be present.
authors.affiliation: Department of Biochemistry, Universiti Kebangsaan Malaysia, Jalan Raja Muda, Kuala Lumpur.
authors.forename: M L
authors.initials: ML
authors.lastname: Ng
authors.forename: T T
authors.initials: TT
authors.lastname: Tan
authors.forename: B A
authors.initials: BA
authors.lastname: Roslan
authors.forename: A
authors.initials: A
authors.lastname: Rajna
authors.forename: B A
authors.initials: BA
authors.lastname: Khalid
mesh_terms: D000293:Adolescent; D000328:Adult; D013956:Antithyroid Agents / Q000627:therapeutic use; D001323:Autoantibodies / Q000097:blood; D005260:Female; D005500:Follow-Up Studies; D006111:Graves Disease / Q000175:diagnosis* / Q000188:drug therapy / Q000276:immunology; D006801:Humans; D006980:Hyperthyroidism / Q000175:diagnosis / Q000188:drug therapy / Q000276:immunology; D007037:Hypothyroidism / Q000175:diagnosis / Q000188:drug therapy / Q000276:immunology; D008297:Male; D008875:Middle Aged; D013960:Thyroid Function Tests; D013967:Thyroiditis, Autoimmune / Q000175:diagnosis / Q000188:drug therapy / Q000276:immunology; D013972:Thyrotropin / Q000097:blood*
chemical_list: D013956:Antithyroid Agents; D001323:Autoantibodies; C006606:anti-thyroglobulin; C056626:thyroid microsomal antibodies; D013972:Thyrotropin