A disease caused by increased production of cortisol or by excessive use of cortisol or other steroid hormones.
Causes, incidence, and risk factors
Cushing's syndrome is a condition that results from an excess of cortisol, a hormone produced by the adrenal glands. The most common cause of Cushing's syndrome is Cushing's disease caused by excessive production of adrenocorticotropic hormone ( ACTH ) by the pituitary gland. ACTH stimulates the adrenal glands to produce cortisol. Cushing's syndrome can be caused by a tumor of the pituitary gland , a tumor of the adrenal gland, a tumor somewhere other than the pituitary or adrenal glands (ectopic Cushing's syndrome), or by long-term use of corticosteroids (drugs commonly used to treat conditions, such as rheumatoid arthritis and asthma ). Risk factors are adrenal tumor or pituitary tumor , chronic therapy with corticosteroids, and being female. See also:
pituitary Cushing's (Cushing's disease)Cushing's syndrome - exogenousectopic Cushing's syndromeCushing's syndrome caused by adrenal tumor
Signs and tests
Tests to confirm high cortisol level :
cortisol, urinedexamethasone suppression test serial serum cortisol levels do not show diurnal variations Tests to determine the cause:
ACTHcranial MRI or cranial CT scan may show pituitary tumor
abdominal CT may show adrenal mass General findings:
glucose test is elevated potassium test may be low white blood cell count may be elevated
Treatment
Treatment depends upon the cause of the disorder. In Cushing's syndrome caused by drug therapy with corticosteroids, the drug must be slowly decreased under medical supervision. In Cushing's disease caused by a pituitary tumor , surgery to remove the tumor is recommended. Sometimes, radiation is needed as well. Hydrocortisone (cortisol) replacement therapy is needed after surgery, and sometimes forever. Cushing's syndrome caused by an adrenal tumor is usually treated by surgical removal of the tumor. If the tumor cannot be removed, certain medications can suppress the secretion of cortisol. In Cushing's syndrome caused by a tumor secreting ACTH, resection of the tumor is the best way to treat the Cushing's syndrome. Cortisol replacement therapy is indicated after surgery until cortisol production resumes. In some cases, life-long therapy with cortisone drugs becomes necessary.
Expectations (prognosis)
Tumor removal may lead to full recovery, but there is a chance of recurrence. Survival for people with ectopic tumors depends upon the overall outcome associated with the particular tumor type. Untreated, Cushing's syndrome can lead to death.
Calling your health care provider
Call your health care provider if symptoms develop that indicate Cushing's syndrome.
Prevention
Cushing's syndrome may be prevented by an awareness of the associated symptoms so that early detection can be made.