Cushing's Syndrome

What is Cushing's syndrome?

Cushing's syndrome is a hormone problem. It happens from too much cortisol in the body. It can happen when:

• You are taking too much steroid medicine.
• Your body is making too much cortisol.

Cortisol is a hormone made by the body in the adrenal glands, which are 2 small glands that sit on top of each kidney. Cortisol has many important functions.

• It helps the body get energy from the sugar and fat in the foods you eat.
• It helps the body respond to physical stress from injury or surgery. For example, it helps keep blood pressure normal in spite of blood loss from an accident.
• The body also makes extra cortisol during the stress of emotional problems such as depression.

Cushing's syndrome is also sometimes called hypercortisolism.

How does it occur?

Cushing's syndrome is usually caused by taking cortisol (steroid) medicine. An example of a commonly used cortisol medicine is prednisone.

Because cortisol has so many functions in the body, it can be very helpful for many medical problems. It is a natural anti-inflammatory, so it is used to stop or lessen the effects of diseases where inflammation is the main problem. For example, it may be used to treat asthma, rheumatoid arthritis, or lupus. Sometimes cortisol medicine is taken on a regular basis (daily or every other day). In other cases it is taken only when a disease is active or causing symptoms. Cortisol is also used to help stop rejection of transplanted organs. For example, if you have had a kidney or other type of transplant, you may need to take a steroid medicine for the rest of your life.

Some people have Cushing’s syndrome because their body is making too much cortisol. The brain and the pituitary gland control how much cortisol the body makes. If your body is making too much cortisol, it is usually because of a tumor in one of your glands. The tumor may be benign (noncancerous) or malignant (cancerous). Common tumors are:

• pituitary adenoma, which is a benign growth in the pituitary gland and causes a type of Cushing’s syndrome called Cushing’s disease
• adrenal tumors, which are usually benign growths in the adrenal gland.

Sometimes other tumors, benign or malignant, can cause your body to make too much cortisol. These tumors are often in the lung, but they can be in glands as well, such as the thyroid or pancreas.

What are the symptoms?

The most common symptoms of hypercortisolism are:

• round face (often called moon face)
• increased fat in the trunk area, that is, the belly and upper back (called buffalo hump)
• easy bruising of the skin
• stretch marks on the skin, especially on the belly, breasts, and thighs
• feeling irritable
• tiredness
• more facial and body hair in women and irregular or stopped menstrual periods
• loss of interest in sex.

Too much cortisol can cause high blood sugar and type 2 diabetes. Symptoms of diabetes include:

• increased thirst and urination
• tiredness
• blurry vision.

It is important to be checked for diabetes if you are having regular steroid treatment. High blood sugar needs to be controlled to prevent other problems.

If you had diabetes (type 1 or type 2) before you started having Cushing's syndrome, you may have trouble keeping good control of your blood sugar.

How is it diagnosed?

The diagnosis is often clear from how you look. Your healthcare provider will take a careful history and examine you. During the exam your provider will look for signs of Cushing's syndrome: high blood pressure; thin, bruised skin; thinning arms and legs; and more fat in the upper body (trunk and abdomen).

If you have been taking steroid medicine, your provider will know the likely cause of your symptoms. The lab tests will be simpler than if the cause is not known. You will probably have blood tests to check things like your blood sugar and liver and kidney function.

If you have not been taking cortisol-type medicines, you may need the following tests:

• skull X-ray, CT scan, or MRI
• urine cortisol test
• dexamethasone suppression test.

For the urine cortisol test, you will collect your urine for 24 hours. The urine is then tested to see if you are making too much cortisol.

The dexamethasone suppression test measures cortisol in your urine and blood and the effect on your cortisol levels when you take dexamethasone. Dexamethasone is a man-made steroid that is similar to cortisol. The test is done to see if your body is making extra cortisol and to help find the cause.

How is it treated?

The treatment depends on the cause. If your symptoms are caused by steroid medicine, you and your healthcare provider will have to see if you can lower the dosage or try other medicines. In some cases your provider may have you try taking your steroid medicine less often. For many people this can lessen the side effects of the medicine.

If you have a tumor that is making cortisol, your treatment may include surgery, chemotherapy, or radiation to treat the tumor.

How long will the effects last?

If the cause is steroid medicine, your symptoms will lessen over several weeks to months as you decrease or stop your medicine. However, some or all of the symptoms are likely to come back if you start taking the medicine again during a flare-up of your illness. It is very important to follow your healthcare provider’s directions exactly when you start taking less steroid medicine. If you lower the dose too quickly or if you just stop it suddenly, it can be dangerous, even life-threatening to you.

If you have a tumor making too much cortisol, your Cushing's syndrome symptoms will gradually lessen after the tumor is treated. You may need to be checked regularly after treatment to make sure the tumor does not come back.

How can I take care of myself?

Make sure you follow your healthcare provider's advice for preventing the complications caused by too much cortisol. You may need to check your blood pressure and your blood sugar regularly.

If you have become very weak or have osteoporosis (weakened bones), you may need physical therapy and an exercise prescription. You may need medicine to make your bones stronger.

What can I do to prevent Cushing's syndrome?

If you are taking steroid medicine for a medical problem, keep all of your follow-up appointments with your healthcare provider. Your provider will check for signs of Cushing's syndrome and the problems it can cause. Researchers are looking for nonsteroid medicines that can treat inflammation and prevent transplant rejection. With time there may be medicines that can help your condition without the side effects of steroids.

Doctors do not know how to prevent the tumors that cause Cushing's syndrome.