Addison's disease

Addison's disease or primary adrenocortical failure is a rare condition, most commonly caused in the UK by autoimmune destruction of the adrenal glands. The insidious onset of symptoms over many months means there is often a delay in diagnosis and patients can first present in adrenal crisis, which is life-threatening if not appropriately treated. The diagnosis is made by the finding of a low serum cortisol at 09:00 hours in the presence of an elevated adrenocorticotrophic hormone (ACTH) concentration, or by a suboptimal cortisol response to exogenous ACTH on provocation testing. Replacement with hydrocortisone and fludrocortisone should approximate physiological concentrations as closely as possible. Patients and family should have a good understanding of their condition and how to adjust corticosteroid dosing in times of illness.