title: Acromegaly with 'normal' serum growth hormone levels. Clinical features, diagnosis and results of transsphenoidal microsurgery.
abstract: Among 216 consecutive patients with growth hormone secreting pituitary adenomas who underwent primary neurosurgical treatment at the University of Erlangen-Nürnberg, 8 cases of acromegaly with 'normal' basal growth hormone levels (less than or equal to 5 ng/ml) were seen. They all had the typical clinical features of acromegaly, exhibited an abnormal growth hormone secretion following an oral glucose load, and had markedly elevated somatomedin C levels. The GRH- and TRH/GnRH-tests were not found helpful in establishing the diagnosis. Neuroradiology could demonstrate a pituitary adenoma in all of the patients. Following transsphenoidal microsurgical resection of the tumours, growth hormone secretion during oral glucose tolerance testing was normalised in 7 of the 8 patients. Immunohistology and explant culture studies documented growth hormone secreting pituitary adenomas in all cases. The authors conclude that even the finding of repetitive 'normal' (less than or equal to 5 ng/ml) serum GH levels does not exclude active acromegaly and when the clinical diagnosis of acromegaly is suspected, dynamic endocrine testing may reveal abnormal secretion patterns of GH in these cases. Transsphenoidal microsurgical resection of a pituitary adenoma offers a good chance of clinical and endocrinological remission in these cases.
authors.affiliation: Neurochirurgische Klinik mit Poliklinik, Friedrich-Alexander Universität Erlangen-Nürnberg, Germany.
authors.forename: S J
authors.initials: SJ
authors.lastname: Brockmeier
authors.forename: M
authors.initials: M
authors.lastname: Buchfelder
authors.forename: E F
authors.initials: EF
authors.lastname: Adams
authors.forename: W
authors.initials: W
authors.lastname: Schott
authors.forename: R
authors.initials: R
authors.lastname: Fahlbusch
mesh_terms: D000172:Acromegaly / Q000097:blood* / Q000175:diagnosis / Q000601:surgery; D000236:Adenoma / Q000097:blood* / Q000175:diagnosis / Q000601:surgery; D000328:Adult; D005260:Female; D005951:Glucose Tolerance Test; D013006:Growth Hormone / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010911:Pituitary Neoplasms / Q000097:blood* / Q000175:diagnosis / Q000601:surgery
chemical_list: D013006:Growth Hormone