title: Post-traumatic hypothalamic-pituitary dysfunction presenting with biochemical features of primary hypothyroidism.
abstract: Two cases of post-traumatic hypothalamic-pituitary dysfunction are described where the primary pathology was shown to be understimulation of the pituitary by hypothalamic hormones. In each case, the biochemical presentation was a low serum thyroxine and elevated TSH concentration mimicking primary hypothyroidism. Treatment with thyroxine before cortisol replacement was not beneficial. In both cases, hydrocortisone therapy alone resulted in a rise in serum thyroxine and fall in serum TSH. Chronic cortisol deficiency may directly impair the thyroid response to TSH, whilst thyroxine appears to exert its feedback primarily at pituitary rather than hypothalamic level.
authors.affiliation: Biochemistry Department, Law Hospital, Carluke, Lanarkshire, UK.
authors.forename: I R
authors.initials: IR
authors.lastname: Gunn
authors.forename: G H
authors.initials: GH
authors.lastname: Beastall
authors.forename: D M
authors.initials: DM
authors.lastname: Matthews
authors.forename: J C
authors.initials: JC
authors.lastname: Bath
mesh_terms: D000328:Adult; D006259:Craniocerebral Trauma / Q000150:complications / Q000503:physiopathology*; D006801:Humans; D006854:Hydrocortisone / Q000627:therapeutic use; D007030:Hypothalamo-Hypophyseal System / Q000503:physiopathology*; D007037:Hypothyroidism / Q000188:drug therapy / Q000209:etiology / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D010903:Pituitary Gland, Anterior / Q000503:physiopathology; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood; D013997:Time Factors
chemical_list: D013972:Thyrotropin; D013974:Thyroxine; D006854:Hydrocortisone