Definition Cushing's syndrome is a disorder of the adrenal glands. The adrenal glands produce too much hormone.
What is going on in the body? The adrenal glands are small endocrine glands located on top of each kidney. They produce many hormones. These include glucocorticoids, mineralocorticoids and other steroid hormones. These hormones are important because they control metabolic processes in the body.
What are the signs and symptoms of the disease? Typical symptoms of too much cortisol are: obesity, hypertension, osteoporosis, muscle weakness, emotional changes and diabetes. Signs of Cushing's syndrome may include easy bruising, skin changes, weakness of the muscles and increased fat deposits.
What are the causes and risks of the disease? A common cause is taking steroids. Steroids are used to treat many conditions. Excessive or prolonged use of steroids can lead to Cushing's syndrome.
Adrenal tumours can produce too much cortisol. These tumours may be benign or cancerous.
Certain tumours can cause ectopic Cushing's syndrome. These tumours can include small-cell cancer of the lung, medullary carcinoma of the thyroid (a cancerous tumour of the thyroid gland) and tumours of the pancreas, thymus or ovary.
Pituitary Cushing's syndrome (also known as Cushing's disease) can cause too much steroid hormone production. In this case, a benign tumour within the pituitary gland causes the problem.
What can be done to prevent the disease? Limiting the amount of steroid hormones given to an individual is recommended. Cushing's syndrome may be unavoidable for those who need high doses of steroids to control disease. Other forms of Cushing's syndrome can not be prevented and must be treated once discovered.
How is the disease diagnosed? Cushing's syndrome is suspected with the signs and symptoms discussed. Blood and urine tests are used to check for excessive steroid production. Tests then determine the specific cause of the Cushing's syndrome. Radiographic imaging may be done to evaluate the pituitary gland, adrenal glands or other sites of possible tumour.
What are the long-term effects of the disease? Persistent Cushing's syndrome may lead to progressive problems with obesity, hypertension, osteoporosis, muscle weakness or diabetes.
What are the risks to others? Cushing's syndrome is not contagious and does not put others at risk.
What are the treatments for the disease? Treatment is based on the individual cause of the Cushing's syndrome. In the case of an adrenal tumour, surgery is required. If the tumour is malignant and has spread, medications are given to decrease the production of steroid hormone.
In the case of pituitary Cushing's or Cushing's disease, surgery can be done to remove the benign pituitary tumour.
Exogenous Cushing's syndrome is treated by lowering the steroid dose. It is critical that this be done slowly so that normal adrenal production of steroid hormones can resume.
Ectopic Cushing's disease can occasionally be treated by removing the tumour. This is often impractical and may not result in complete suppression of ACTH production. In this situation, removing the adrenal glands or medical management can be done.
What are the side effects of the treatments? Side effects are specific to the medication used. In the case of surgery, they are related to other risks involved with the procedure.
What happens after treatment for the disease? The individual will need frequent evaluation to ensure the problem has been solved. Conversely, some may become deficient in steroid hormone production. They may need steroid hormones after treatment to maintain normal levels.
How is the disease monitored? As discussed, the individual is monitored with blood tests and physical examinations to check the level of steroid hormone production.
Author: Bill Harrison, MD Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request
