Cushing's Syndrome
(Cushing's Disease; Hypercortisolism)
Definition | Causes | Risk Factors | Symptoms | Diagnosis | Treatment | Prevention
Definition
Cushing's syndrome is a hormonal disorder. It is caused by prolonged exposure to the hormone cortisol.
Hormones are chemicals in the body. Cortisol is a common hormone. In normal doses it helps the body manage stress and infection.
Causes
Prolonged or excess exposure to cortisol as a result of:
- Long-term use of corticosteroid hormones such as cortisone or prednisone
- Tumor or abnormality of the adrenal gland, which causes the body to produce excess cortisol
- Tumor or abnormality of the pituitary gland, which causes the body to produce excess cortisol (in the case of a pituitary tumor, it is called Cushing's disease)
- Rarely, tumors of the lungs, thyroid, kidney, pancreas, or thymus gland produce hormones that trigger the syndrome
Pituitary and Adrenal Glands
© 2009 Nucleus Medical Media, Inc.
Risk Factors
Factors that increase your risk of Cushing's syndrome include:
- Chronic use of corticosteroid medicines
- Age: 20-50 years
- Sex: female (much more common in women)
Symptoms
Although symptoms may vary, common symptoms of Cushing's syndrome are:
- Weight gain of the upper body and trunk
- Face shaped like a moon
-
Skin changes:
- Darkening of the skin
- Purple stretch marks
- Easy bruising
- Excess hair growth or acne in women
- Menstrual disorders, especially infrequent or absent periods
- Diminished fertility and libido
- High blood pressure
- Water retention or swelling
- High blood sugar or diabetes
- Tiredness or fatigue
- Personality changes or mood swings
- Muscle weakness
- Osteoporosis or brittle bones
- Skeletal growth retardation in children
- Increased thirst
- Frequent urination
- Psychosis
- Low back pain
Diagnosis
The doctor will ask about your symptoms and medical history. A physical exam will be done.
Tests for Cortisol Levels
- 24-hour urinary free cortisol level—Urine is collected for 24 hours and tested.
- Late-evening cortisol saliva/blood level—Saliva or blood is collected around 11 pm and tested.
- Dexamethasone suppression test—A synthetic cortisol called dexamethasone is taken by mouth; blood and urine samples may be taken overnight or over several days.
Tests to Determine Cause of Cushing's Syndrome
- CRH stimulation test
- ACTH level
- High-dose dexamethasone suppression test
X-rays and Scans
These tests may show whether there is a tumor in the pituitary or adrenal glands or another area of the body. Common imaging tools include:
- MRI scan —a test that uses magnetic waves to make pictures of the inside of the body
- CT scan —a type of x-ray that uses a computer to make pictures of structures inside the body
- Chest x-ray —which may detect tumors in the lungs
Treatment
Treatment of Cushing's syndrome depends on the cause.
Treatments include:
- Surgical removal of tumor
- Surgical removal of part, all, or both adrenal glands
- Radiation for some persistent tumors
- Gradual withdrawal of cortisone-type drugs under close medical supervision
- Drugs that decrease cortisol production or block the functioning of other adrenal products
Prevention
Work with your doctor to keep use of corticosteroid drugs to a minimum.
RESOURCES:American Academy of Family Physicians
http://familydoctor.org/
Cushing's Support and Research Foundation
http://www.CSRF.net/
Canadian Family Physician
http://www.cfpc.ca/cfp/
Health Canada
http://www.hc-sc.gc.ca/index_e.html
REFERENCES:
Arnaldi G, Angeli A, Atkinson AB, Bertagna X, et al. Diagnosis and complications of Cushing’s syndrome: a consensus statement. J Clin Endocrinolo Metabo . 2003;88:5593-5602.
Cushing's Syndrome. National Institute of Diabetes and Digestive and Kidney Diseases website. Available at: http://www.niddk.nih.gov/health/endo/pubs/cushings/cushings.htm . Updated July 2008. Accessed July 8, 2009.
Diez JJ, Iglesias P. Pharmacological therapy of Cushing’s syndrome: drugs and indications. Mini Rev Med Chem . 2007;7(5):467-480.
Fauci AS, Braunwald E, Isselbacher KJ, et al. Harrison's Principles of Internal Medicine . 14th ed. New York, NY: The McGraw-Hill Companies; 2000.
Kirk LF Jr, Hash RB, Katner HP, Jones T. Cushing's disease: clinical manifestations and diagnostic evaluation. Am Fam Physician . 2000;62(5):1119-1127, 1133-1134.
Makras P, Toloumis G, Papadoglas D, et al. The diagnosis and differential diagnosis of endogenous Cushing’s syndrome. Hormones . 2006;5:231-250.
Yaneva M, Mosnier-Pudar H, Dugue MA, et al. Midnight salivary cortisol for the initial diagnosis of Cushing’s syndrome of various causes. J Clin Endocrinol Metab . 2004;89(7):3345-3351.
Last reviewed September 2009 by Bridget Sinnott, MD, FACE
Last Updated: 9/30/09