There are a few different causes of Cushing's syndrome. Cushing's disease is one common cause of the Cushing's syndrome that occurs when the pituitary releases excess ACTH, leading to extra cortisol being made. This can result from a pituitary tumor or other growth. Iatrogenic Cushing's syndrome can result from taking an excessive amount of steroids, usually from a medication used to treat asthma, lupus and rheumatoid arthritis, among other diseases.
Finally, another cause, though less common, is caused directly from a tumor on the adrenal glands. These types of tumors cause high levels of cortisol, independent of ACTH production from the pituitary gland. When the tumor is only on one adrenal gland, the excess amount of cortisol produced can cause the non-affected adrenal gland to begin to shrivel and shrink.
Symptoms
Symptoms of Cushing’s syndrome include the following:- round, full face (known as moon face)
- obesity around the trunk
- weakness
- acne
- headache
- increased urination
- menstrual changes
- hirsutism
- Buffalo hump (extra fat deposited on the back of the neck)
- skin changes
- psychological symptoms such as mood instability, depression, anxiety, panic attacks
Diagnosis
There are distinguishable physical characteristics, such as the round moon face and buffalo hump, that are typical in a person with Cushing’s syndrome. If the physician suspects Cushing’s, after the routine history, physical exam and basic blood work, s/he will order blood and urine tests to measure the amount of cortisol produced. If those levels are high, the doctor may order a test called a Dexamethasone suppression test. You will be given an oral steroid called dexamethasone, and again have blood and urine tests to measure cortisol and other adrenal hormones.Your doctor may start with an overnight test, and move to a more intensive testing procedure if the screening is abnormal. S/he may also move directly to the more intense testing. Finally, if the dexamethasone testing is abnormal, more specific testing of the blood and serum is performed. The doctor may also order a CT or MRI to determine the presence and location of a tumor if suspected. While the testing can seem like a lot of work, or inconvenient, it is important to follow up and complete all of the testing that the doctor orders due to the potential implications for your health.
Treatment
Cushing's syndrome is best treated by determining what is causing the high levels of cortisol, and removing it. Surgery is usually the first line treatment for patients with Cushing's disease. Removal of the pituitary tumor, and sometimes the entire pituitary gland can be necessary. If the entire pituitary needs to be removed, supplements of cortisol, thyroid and sex hormones will need to be given. If surgery is contraindicated or the tumor cannot be removed, radiation therapy can be used to shrink the tumor.Surgery may be necessary if the tumor is found to be elsewhere as well. If the tumor is found to be malignant, chemotherapy or radiation may be prescribed to reduce your risk of reoccurrence.
If the syndrome is being caused by a prescribed medication, it is best to begin to taper the medication off, supervised by your doctor, to remove the excess steroid. A different medication or dose may be more appropriate, and only your doctor can help you determine that. It is important to follow the instructions precisely, as steroids can not be stopped suddenly, but must be slowly tapered down.
Sources:
Margulies, Paul. Adrenal Diseases - Cushing’s Syndrome: The Facts You Need to Know. National Adrenal Diseases Foundation. Accessed 28 January 2008. Http://www.nadf.us/diseases/cushings.htm
