title: [Ultrasensitive determination of thyrotropin. Improvement in the performance and reduction of the cost of thyroid function tests].
abstract: The characteristics of an ultrasensitive thyrotropin (TSH) assay method using monoclonal antibodies (TSH-U) were determined in euthyroid subjects, either healthy or with extra-thyroid disease, in treated and untreated hyper-and hypothyroid subjects and in subjects under amiodarone. The thyroid function was evaluated by free thyroxine (FT4) and free triiodothyronine (FT3) assays and by TSH tests and TSH response to TRH. With a sensitivity of 1 and a specificity of 0.94, the TSH-U assay proved highly reliable to evaluate the thyroid function. Dysthyroidism can be excluded when TSH-U levels are normal (0.15 to 4.5 microU/ml). In case of low TSH-U level, measurements of FT4 and FT3 and, if required, thyroid gland scintigraphy are necessary to confirm a diagnosis of hyperthyroidism. In contrast, a high TSH-U level is sufficient for affirm diagnosis of hypothyroidism. The TSH-U assay makes the TRH test redundant and can differentiate between hyperthyroxinaemia with euthyroidism and with hyperthyroidism. It is an effective method to detect disorders in thyroid function and it calls for a re-evaluation of thyroid diagnostic strategy.
mesh_terms: D000328:Adult; D003363:Cost Control; D005260:Female; D006801:Humans; D006980:Hyperthyroidism / Q000097:blood; D007037:Hypothyroidism / Q000097:blood; D008297:Male; D008875:Middle Aged; D013959:Thyroid Diseases / Q000175:diagnosis*; D013960:Thyroid Function Tests / Q000191:economics / Q000379:methods; D013972:Thyrotropin / Q000097:blood*
chemical_list: D013972:Thyrotropin
vernacular_title: Dosage ultra-sensible de l'hormone thyréotrope. Amélioration des performances et réduction du coût de l'exploration fonctionnelle thyroïdienne.