title: [Role of ultrasensitive TSH assay and ultrarapid total thyroxine assay in the thyroid studies].
abstract: The diagnostic value of high sensitivity thyrotrophin assay (HS-TSH) and that of ultra-short determination of total thyroxine (T4) by fluorescence polarization (T4-TDX) were evaluated in 284 patients (29 hyperthyroid, 137 euthyroid without treatment and 118 under substitutive therapy). After comparing the clinician's first impression with the results of these laboratory tests the proportion of correctly classified untreated euthyroid patients was the same with T4-TDX as with HS-TSH (90%). In contrast, this proportion in hyperthyroid patients was about twice as low with HS-TSH (23%) as with T4-TDX (42%). While HS-TSH gives a better diagnostic evaluation, T4-TDX is an excellent indicator of the degree of hyperthyroidism. In patients under suppressive therapy HS-TSH and T4-TDX provide a better evaluation of therapeutic effectiveness.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005069:Evaluation Studies as Topic; D005260:Female; D005454:Fluorescence Polarization; D006801:Humans; D008297:Male; D008875:Middle Aged; D011863:Radioimmunoassay; D013959:Thyroid Diseases / Q000097:blood* / Q000175:diagnosis / Q000503:physiopathology; D013960:Thyroid Function Tests / Q000379:methods*; D013972:Thyrotropin / Q000097:blood*; D013974:Thyroxine / Q000097:blood*
chemical_list: D013972:Thyrotropin; D013974:Thyroxine
vernacular_title: Places du dosage ultrasensible de la TSH et du dosage ultrarapide de la thyroxine totale dans l'exploration thyroïdienne.