Cushing’s syndrome

Definition

Cushing's syndrome is 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 the 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 for Cushing's syndrome are adrenal or pituitary tumors, long-term therapy with corticosteroids, and being female.

See also:

• Cushing's disease (pituitary Cushing's)
• Cushing's syndrome - exogenous
• ectopic Cushing's syndrome
• Cushing's syndrome caused by adrenal tumor

Symptoms

• moon face (round, red, and full)
• buffalo hump (a collection of fat between the shoulders)
• central obesity with protruding abdomen and thin extremities
• weight gain (unintentional)
• weakness
• backache
• headache
• acne or superficial skin infections
• thin skin with easy bruising
• thirst
• increased urination
• purple striations on the skin of the abdomen, thighs, and breasts
• mental changes
• impotence or cessation of menses
• facial hair growth

• skin spots, red
• skin blushing / flushing
• muscle atrophy
• fatigue
• bone pain or tenderness
• high blood pressure

Signs and tests

Tests to confirm high cortisol level:

• cortisol, urine
• dexamethasone suppression test
• serial serum cortisol levels

• ACTH
• cranial 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 dose must be slowly decreased under medical supervision.

In Cushing's disease caused by a pituitary tumor, surgery to remove the tumor is recommended. Radiation is sometimes needed as well. Hydrocortisone (cortisol) replacement therapy is needed after surgery. In some cases, life-long cortisol-replacement therapy becomes necessary.

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, removal of the tumor is the best way to treat the Cushing's syndrome. Cortisol replacement therapy is needed 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.

Complications

• diabetes mellitus
• high blood pressure
• serious infections
• fractures due to osteoporosis
• kidney stones
• enlargement of pituitary tumor

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.

Illustrations

Endocrine glands

Page Content:

Hypercortisolism ; hypercortisolism