Cushing's disease (also known as
Cushing disease,
tertiary or secondary hypercortisolism,
tertiary or secondary hypercorticism,
Itsenko-Cushing disease) is a cause of
Cushing's syndrome characterised by increased secretion of
adrenocorticotropic hormone (ACTH) from the
anterior pituitary (
secondary hypercortisolism). This is most often as a result of a pituitary
adenoma (specifically pituitary basophilism) or due to excess production of hypothalamus CRH (
Corticotropin releasing hormone) (
tertiary hypercortisolism/hypercorticism) that stimulates the synthesis of cortisol by the adrenal glands. Pituitary adenomas are responsible for 80% of endogenous Cushing's syndrome, when excluding Cushing's syndrome from exogenously administered
corticosteroids.