title: The practical use of thyroid function tests.
abstract: The diagnosis of thyroid disorders can usually be established by two tests: the serum T4 and the resin T3 uptake (RT3U). The T4 test measures both free and bound thyroxine; the RT3U reflects the number of binding sites available on thyroid-binding globulin. The values of these two tests can be used to calculate a free thyroxine index (FTI), which gives an approximation of the free T4 in the serum. Measurement of thyroid-stimulating hormone (TSH) is useful for the diagnosis of hypothyroidism, while the thyrotropin-releasing hormone (TRH) test may facilitate diagnosis of hyperthyroidism.
mesh_terms: D005260:Female; D006801:Humans; D006980:Hyperthyroidism / Q000097:blood; D007037:Hypothyroidism / Q000097:blood; D007457:Iodine Radioisotopes; D009404:Nephrotic Syndrome / Q000097:blood; D011247:Pregnancy; D011248:Pregnancy Complications / Q000097:blood; D013959:Thyroid Diseases / Q000175:diagnosis*; D013960:Thyroid Function Tests / Q000379:methods*; D013961:Thyroid Gland / Q000378:metabolism; D013972:Thyrotropin / Q000097:blood; D013973:Thyrotropin-Releasing Hormone / Q000097:blood; D013974:Thyroxine / Q000097:blood; D013975:Thyroxine-Binding Proteins / Q000032:analysis; D014284:Triiodothyronine / Q000097:blood
chemical_list: D007457:Iodine Radioisotopes; D013975:Thyroxine-Binding Proteins; D014284:Triiodothyronine; D013973:Thyrotropin-Releasing Hormone; D013972:Thyrotropin; D013974:Thyroxine