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. The diagnosis is made by the finding of a low serum cortisol at 09.00 hours in the presence of an elevated adrenocorticotropic hormone (ACTH) concentration, or by a poor cortisol response to exogenous ACTH on provocation testing. Replacement with hydrocortisone and fludrocortisone should approximate physiological levels as closely as possible and be regularly monitored.