ACTH: Over production of ACTH, usually the result of a basophil micro-adenoma, can result in Cushing’ disease because of adrenal cortex overstimulation.
The symptoms and signs may include central obesity, hypertension, plethora, poor wound healing, striae, easy bruising, diabetes, osteoporosis and muscle atrophy.
The treatment is by trans-sphenoidal excision of the adenoma.
Prolactin: Over production of Prolactin is usually the result of a micro-adenoma (size less than 1cm) or macro-adenoma (size 1 cm or more). Large adenoma may affect the anatomy of the Sella Turcica and compress the optic chiasma.
The symptoms and signs include galactorrhoea, menstrual cycle disturbance, visual fields defects, headaches and well as low testosterone levels in males.
Prolactin levels are increased. Brain MRI and CT demonstrate the enlarged pituitary gland and its surroundings. Treatment is by Dopamine antagonists, e.g. Cabergoline, which should be taken long term. Rarely surgery is required to decompress the Sella Turcica.
It is important to note that Cabergoline and similar medication may affect behaviour in a manner that is of concern to flight safety.
Growth hormone: Overproduction of growth hormone results in acromegaly. The symptoms and signs include increased bone size that is most visible on hands, feet and face. Soft tissues enlargement also occurs with thicken skin, lips, tongue and ears enlargement.
The key biochemistry tests include insulin like growth factor 1 (IgF-1) level determination which may show an elevation, and GH determination following oral glucose loading which normally suppresses GH significantly but not in acromegaly. MRI will generally show the pituitary tumour.
If no tumour is seen a GHRH level may reveal the existence of a non-pituitary GHRH producing tumour somewhere else in the body. Treatment is most often surgical but also by irradiation and medication.
Antidiuretic Hormone (Vasopressin - ADH): Underproduction results in polyuria (Diabetes Insipidus). Fluid deprivation secures the diagnosis if the urine remains diluted despite a raise in osmolality over 295 mOsm/kg. Treatment is by titrated Desmopressin, usually administered as a nasal spray.
On the first occasion that an applicant presents with a pituitary gland disorders:
On subsequent occasions that an applicant present with a history of pituitary gland disorder: