Background and Signs and Symptoms

What is Cushing’s syndrome?

Cortisol is a steroid hormone made by the adrenal glands. Normal levels of cortisol are necessary to sustain life, maintain normal sleep-wake cycles, and allow the body to respond to stressful events. Although limited bursts of cortisol are normal, long-term elevations can be harmful. People with too much cortisol in their blood are given the diagnosis of Cushing’s syndrome.

People who take steroid prescription medications in high doses for a long period of time may develop the symptoms of Cushing’s syndrome. These medications are often used to treat inflammatory diseases (such as rheumatoid arthritis, asthma, and inflammatory bowel disease) and are the most common cause of “Cushing’s syndrome” symptoms. The most commonly prescribed steroid medication is called prednisone.

Alternatively, if someone’s body makes too much cortisol, there are 3 possible sources:

  1. Pituitary gland — A small tumor in the pituitary gland, which lies at the base of the brain, may be producing too much ACTH (adrenocorticotropic hormone). ACTH is a hormone that controls the production of cortisol by the adrenal glands. Too much ACTH leads to excess production of cortisol by both adrenal glands. Pituitary tumors are the most common cause of Cushing’s syndrome (aside from taking to much steroid medication), making up about 70% of cases.
  2. Adrenal gland — A tumor in one of the adrenal glands may be producing too much cortisol. Adrenal tumors are responsible for Cushing’s syndrome in about 20% of cases.
  3. A site other than the pituitary or adrenal gland (ectopic) — This accounts for about 10% of cases of Cushing’s syndrome. Sometimes it is called ectopic ACTH syndrome. This happens when a tumor outside of the pituitary makes too much ACTH. The most common places for an ectopic ACTH-producing tumor are in the lung and thymus, both located in the chest. Just like a pituitary tumor, these ectopic tumors make too much ACTH, causing both adrenal glands to become hyperactive and produce too much cortisol.

Signs and Symptoms

Signs and symptoms of Cushing’s syndrome include:

  1. Weight gain – particularly around the gut or mid-section
  2. “Moon facies” – a rounded shape of the face
  3. Easy bruising
  4. “Buffalo hump” – a mound of fat at the base of the back of the neck.
  5. Abnormal hair growth – women with Cushing’s syndrome may develop more hair growth on the face or near the belly button.
  6. Edema (leg swelling) – due to excess fluid buildup in the lower legs and feet.
  7. Purple striae – most common around the sides and lower abdomen, these may have a pink, red, or purple color.
  8. High blood pressure
  9. Diabetes (high blood sugar levels)
  10. Mood changes – many patients feel “hyper”, others may experience sudden emotional ups and downs or be quick to anger.
  11. Thinning of the skin – the skin may develop a shiny, paper-thin quality and may rip or tear easily.
  12. Facial plethora (ruddy complexion) – a reddening of the face or cheeks.
  13. Muscle weakness – the arms and legs may become skinny like twigs from muscle  wasting.
  14. Menstrual disturbances – a woman’s period may be irregular or stop altogether.

Some of the above symptoms are nonspecific and can occur as a result of other conditions. Overall, Cushing’s syndrome is a very rare cause of weight gain. In other words, most weight gain that occurs in the United States is a result of poor diet choices and lack of exercise. Of the above signs and symptoms, the ones most specific to Cushing’s syndrome are easy bruising, muscle weakness, and facial plethora.