title: Pituitary enlargement, pituitary failure, and primary hypothyroidism.
abstract: Enlargement of the pituitary gland associated with primary hypothyroidism was observed in two patients. Serum thyroid-stimulating hormone (TSH) concentration and the TSH response to thyrotropin-releasing hormone were increased in both. Other pituitary function tests were subnormal in both patients, suggesting that a thyrotroph pituitary tumor was present that compromised the other pituicytes. The presence of a pituitary tumor secondary to primary hypothyroidism and resulting pituitary failure should be considered in all patients with long-standing primary hypothyroidism.
mesh_terms: D000238:Adenoma, Chromophobe / Q000188:drug therapy / Q000209:etiology; D000368:Aged; D006801:Humans; D007037:Hypothyroidism / Q000150:complications*; D008297:Male; D008875:Middle Aged; D010900:Pituitary Diseases / Q000150:complications*; D010911:Pituitary Neoplasms / Q000188:drug therapy / Q000209:etiology; D012658:Sella Turcica; D013960:Thyroid Function Tests; D013972:Thyrotropin / Q000378:metabolism; D013974:Thyroxine / Q000627:therapeutic use; D014284:Triiodothyronine / Q000627:therapeutic use
chemical_list: D014284:Triiodothyronine; D013972:Thyrotropin; D013974:Thyroxine