What is Cushing's syndrome?

Cushing's syndrome is a rare hormonal problem. It happens when there is too much of the hormone cortisol in your body.

Normally, cortisol levels increase through a chain reaction of hormones:

1. First, the brain makes a hormone called CRH (corticotropin-releasing hormone).
2. Then, CRH tells the pituitary gland to make another hormone called ACTH (adrenocorticotropic hormone).
3. ACTH then tells the adrenal glands to make cortisol. Cortisol affects almost every area of the body. It is especially important in regulating blood pressure and metabolism.

But if your body makes too much cortisol-or if you take certain medicines that act like cortisol-you may start to have symptoms. Cushing's syndrome may cause weight gain, skin changes, and fatigue. It can lead to serious problems, such as diabetes, high blood pressure, depression, and osteoporosis. If not treated, it can also cause death.

Another name for Cushing’s syndrome is hypercortisolism.

What causes Cushing's syndrome?

Cushing's syndrome may be caused by:

• Steroidmedicine. This medicine is used to treat lupus, asthma, rheumatoid arthritis, and other diseases that cause inflammation. It may also be used after an organ transplant. Long-term use of this medicine is the most common cause of Cushing's syndrome.
• Tumors on the pituitary gland. This is called Cushing's disease. It’s the second most common cause of Cushing's syndrome. These tumors are not cancer.
• Tumors on the adrenal glands, or in the lung or pancreas. Sometimes these tumors are cancer.

What are the symptoms?

Weight gain-especially around the waist-is the most common symptom.

Cortisol affects almost all body systems, so it can cause many other symptoms. These other symptoms often appear slowly over time and may include:

• Weak muscles.
• Changes in the skin, such as bruising, acne, and dark purple-red stretch marks on the belly.
• Changes in mood. You may feel irritable, anxious, or depressed.
• Extra fat on the back of the neck and upper back.
• Backaches.
• Loss of muscle tone.
• Irregular menstrual periods.
• Hair growth that is not normal (such as facial hair in women).
• High blood pressure and high blood sugar levels.

Sometimes alcoholism, depression, panic attacks, obesity, or other problems can cause symptoms like these. Some treatments for HIV can also cause similar symptoms. This is called pseudo-Cushing's syndrome. In these cases, symptoms tend to stop as soon as the problems are treated.

How is Cushing's syndrome diagnosed?

Your doctor will use your medical history, a physical exam, and lab tests to see if you have Cushing's syndrome. During the physical exam, he or she will look for signs of the problem. The medical history includes questions about your symptoms, what medicines you take, and-if you are a woman-whether your periods are regular.

If your doctor thinks you may have Cushing's syndrome, you will have lab tests to check your cortisol levels. These tests can measure cortisol in your blood, urine or saliva. More tests may be needed to find the cause of high cortisol levels.

How is it treated?