title: [Diminution of thyroid stimulating hormone level but normal levels of thyroid hormones. Demonstration of occult hyperthyroidism].
abstract: The finding of a low basal concentration of thyroid-stimulating hormone (TSH) in the absence of high thyroid hormone levels is difficult to understand. In order to elucidate the meaning of such a dissociation, 22 patients without history of thyroid disease and showing clinical signs compatible with thyrotoxicosis were explored by the thyrotrophin-releasing hormone (TRH) test, by thyroid radioisotope scanning and, in case of high nodular uptake, by the triiodothyronine suppression test. A specific surgical, isotopic or medical treatment was instituted in the 17 patients who had a high nodular uptake unsupressible by triiodothyronine. During a clinicobiological re-evaluation carried out 6 months later, a significant clinical improvement was observed in 8 patients, and 12 patients whose free thyroxine level had decreased showed normal TSH levels. These results underline the value of thyroid radioisotope scanning in patients with isolated diminution of TSH. They confirm the reality of occult hyperthyroidism with normal thyroid hormone levels by the benefits observed after specific treatment.
authors: Service de Médecine interne, Hôpital de Hautepierre, CHU, Strasbourg.
authors: J L
authors: JL
authors: Schlienger
authors: M
authors: M
authors: Klerlein
authors: R
authors: R
authors: Sapin
authors: J L
authors: JL
authors: Demangeat
authors: M
authors: M
authors: Imler
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D013956:Antithyroid Agents / Q000627:therapeutic use; D005260:Female; D006801:Humans; D006980:Hyperthyroidism / Q000097:blood / Q000175:diagnosis* / Q000628:therapy; D007457:Iodine Radioisotopes / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D013965:Thyroidectomy; D013972:Thyrotropin / Q000097:blood*; D013974:Thyroxine / Q000097:blood*; D014284:Triiodothyronine / Q000097:blood*
chemical_list: D013956:Antithyroid Agents; D007457:Iodine Radioisotopes; D014284:Triiodothyronine; D013972:Thyrotropin; D013974:Thyroxine
vernacular_title: Diminution de la thyréostimulinémie et hormonémie thyroïdienne normale. Mise en évidence d'une hyperthyroïdie occulte.