Pituitary hormone excess

Last updated: Saturday, 22, January, 2011
CausesAppropriate Tests

Increased levels of pituitary hormones may be the result of autonomous production by pituitary adenomas, release from inhibitory feedback mechanisms, or ectopic secretion.

One or more hormones may be increased and if there is a pituitary lesion, there may be associated deficiency of one or more hormones.

See also Pituitary/hypothalamic disorders.

ADH excess

See SIADH

Growth hormone excess

Acromegaly, gigantism (in childhood).

IGF-I; growth hormone suppression test.

Pituitary adenoma

Ectopic syndromes (rare)

Pancreatic islet cell tumour

See under Pancreatic neoplasm

Carcinoid tumour (lungs, adrenals)

Adrenocorticotrophin excess 

Dexamethasone suppression test (overnight); cortisol (free) - urine.

Then, if indicated, dexamethasone suppression test (long) including ACTH.

See Cushing's syndrome

Pituitary adenoma 

Cushing's disease.
Clinical features of Cushing's syndrome.

Ectopic ACTH syndrome 

Patients may have clinical features of Cushing's syndrome.

Nelson's syndrome 

Patients are not Cushingoid. ACTH is the appropriate test.

Prolactin excess 

Present with amenorrhoea and/or galactorrhoea.

Prolactin; repeat, if elevated, to document persistent elevation.

See also Infertility

Prolactinoma

Other pituitary tumour

Physiological

  • Post-oral contraceptive use
  • Stress

Drugs, especially

  • Cimetidine
  • Methadone
  • Metoclopramide

Thyrotrophin excess

'Pituitary' Hyperthyroidism: TSH, thyroxine (free).

See Hyperthyroidism

Pituitary adenoma

Pituitary T4 resistance

Gonadotrophin excess 

Precocious puberty, Gynaecomastia. In many cases, there are no clinical features suggesting an endocrine disorder.

LH, FSH, alpha subunit, testosterone or oestradiol.

Pituitary adenoma

Ectopic syndromes, especially 

  • Germinoma
  • Carcinoma lung
  • Hepatocellular carcinoma

Human chorionic gonadotrophin (beta subunit).

Alpha subunit excess

These patients do not present with clinical features of an endocrine disorder: alpha subunit.

Alpha subunit secreting tumours