Alternate Names : Hypercortisolism
Cushing's syndrome is a hormonal disorder that occurs when the body tissues are exposed to high levels of the hormone cortisol. The adrenal glands produce cortisol. Cushing's disease is the most common type of Cushing's syndrome. It is caused by a noncancerous tumor of the pituitary gland.
What is going on in the body?
Cushing's syndrome occurs when body tissues are exposed to high levels of cortisol for a long time. Cortisol is an important hormone that regulates many body functions, including stress management. A part of the brain known as the hypothalamus sends CRH, a hormone, to the pituitary gland. The pituitary gland then produces another hormone called ACTH. The ACTH then stimulates the adrenal glands to produce cortisol. The hypothalamus and pituitary monitor blood levels of cortisol. They adjust their hormone release as needed. This maintains a normal balance of cortisol.
Sometimes the cortisol balance in the body is thrown off. The person may have excess cortisol under the following conditions:
he or she takes glucocorticoid medicines, such as prednisone, for a long time
tumors of the pituitary gland produce excess ACTH
tumors outside the pituitary secrete ACTH
abnormalities, including tumors, of the adrenal glands cause excess cortisol production
What are the causes and risks of the disease?
Cushing's syndrome occurs when body tissues are exposed to high levels of cortisol over a long period of time. These high levels may be caused by:
certain cancerous or noncancerous tumors of the lung, thyroid, pancreas, or ovary. These tumors produce a form of Cushing's syndrome known as ectopic ACTH syndrome.
disorders of the adrenal glands
familial Cushing's syndrome, which involves tumors of one or more endocrine glands
pituitary adenoma, a noncancerous tumor that causes Cushing's disease
prolonged use of glucocorticoid medicines, such as prednisone
tumors of the adrenal glands, which may be cancerous or noncancerous