9: Pituitary disease in adults

Pituitary adenomas are found in 10%–25% of unselected autopsy series and are evident in about 10% of asymptomatic individuals by magnetic resonance imaging. Diagnosis of pituitary disorders is often delayed by lack of awareness and the subtlety of symptoms and signs. Hypopituitarism is suspected when peripheral hormone concentrations are low without an elevation in the corresponding pituitary tropic hormone(s). Severe adult‐onset growth‐hormone deficiency results in reduced muscle mass, increased fat mass and diminished quality of life, which are reversed by growth hormone replacement therapy. While trans‐sphenoidal surgery remains first‐line treatment for acromegaly, drug treatment has an important role in controlling residual growth‐hormone excess and, in some circumstances, as first‐line treatment. Dopamine‐agonist therapy (cabergoline or bromocriptine) is the treatment of choice for micro‐ and macroprolactinomas. In patients with suggestive clinical features, elevated 24‐hour urine free cortisol level is usually sufficient to diagnose endogenous Cushing's syndrome; careful additional investigation is needed to determine whether the cause is Cushing's disease (pituitary adenoma secreting adrenocorticotropic hormone [ACTH]), ectopic ACTH secretion or adrenal disease.