Cushing's Syndrome

Cushing's syndrome is a group of abnormalities resulting from an excess of the hormones produced by the cortex of the adrenal glands. The hormones produced in excess are chiefly cortisol, which has many complex functions; various hormones that regulate the body's use of sugars and proteins; male sex hormones; and a hormone that controls the distribution of fluids and salts in the body.

Causes

In most cases, Cushing's syndrome is caused by excess production of adrenocorticotropic hormone (ACTH), which is normally manufactured by the pituitary gland to stimulate production of hormones by the adrenal glands. This excess of ACTH can be caused by an ACTH-producing tumor in another organ, such as the lung or pancreas; by overmedication with ACTH or a corticosteroid; by tiny, nonmalignant ACTH-producing tumors on the pituitary gland; or by a tumor (usually benign) on the adrenal gland. The effect of too much ACTH, for whatever reason, is overgrowth of tissue in the adrenal cortex, resulting in overproduction of all its hormones.

Since these hormones regulate essential processes throughout the body, excess production causes widespread disorders.

Symptoms

One of the most obvious signs of Cushing's syndrome is the moon-shaped face, caused by excess fluid in the tissues. Because of deposition of excess fat, the torso is obese (although the arms and legs are thin), and there are fat pads over the shoulders and neck, producing a "buffalo hump." Purple "stretch marks" on the skin (usually of the abdomen), poor wound healing, easy bruising, muscle weakness, fractures in weakened bones, and emotional instability may also be part of the syndrome. Hairiness, acne, and decreased or absent menstruation may occur in women, due to the increase in male hormones. Diabetes and high blood pressure are also very common.

Diagnosis

Diagnosis of Cushing's syndrome requires measurement of adrenal cortex hormones in the blood and urine. In healthy people, cortisol levels in the blood are high on awakening but decrease during the day; in the person with Cushing's syndrome, cortisol levels are high all of the time. Various tests can determine whether the cause of the syndrome is a tumor of the pituitary gland (in which case the disorder is known as Cushing's disease) or a tumor on the adrenal gland or elsewhere. Tumors on the adrenal glands may be identified by X rays, ultrasound, and computed tomography (CT) scans. CT scans and special X rays of the head can often locate tumors of the pituitary gland.

Treatment

Cushing's syndrome is treated by restoring a normal balance of hormones. This may involve surgery, radiation treatments, or drugs. Tumors on the adrenal glands are removed by surgery. If there is a tumor on just one adrenal gland, the other gland usually shrinks and ceases normal productivity. Hormone supplements are usually given before surgery and must be taken for weeks or months after surgery until the second gland recovers normal function. In a rapidly worsening case of Cushing's syndrome in which the cortex is greatly enlarged on both sides, methods of treatment include chemotherapy (drug treatments), radiation treatments of the pituitary gland (to weaken it and lower its output of ACTH), or removal of any adenomas (nonmalignant growths) on the pituitary gland. The removal of the adrenal glands is usually a last-resort measure. In this case, the patient must take daily supplements of adrenal cortex hormones for the rest of his or her life.

If Cushing's syndrome is being caused by production of ACTH by a cancerous tumor in a part of the body other than the adrenal glands, the cancer is removed, if possible. However, in many cases it is inoperable, so drugs to suppress production of the adrenal glands are given.

Cushing's syndrome is a very serious, possibly fatal, disease unless it is detected and treated early. The outlook is best for those whose condition is caused by noncancerous growths and who receive early treatment.

Those who must take replacement hormones after treatment should carry a medical identification card and immediately tell their doctor about any infections, injuries, or stressful situations that might require an increase in hormone dosage. They should also report signs of underdosage, such as weakness, dizziness, or fatigue, as well as signs of overdosage, such as swollen tissues and rapid weight gain. Anyone whose adrenal glands have been removed must always take replacement hormones; stopping these medications for any length of time is fatal.



This information is solely for informational purposes. IT IS NOT INTENDED TO PROVIDE MEDICAL ADVICE. Neither the Editors of Consumer Guide (R), Publications International, Ltd., the author nor publisher take responsibility for any possible consequences from any treatment, procedure, exercise, dietary modification, action or application of medication which results from reading or following the information contained in this information. The publication of this information does not constitute the practice of medicine, and this information does not replace the advice of your physician or other health care provider. Before undertaking any course of treatment, the reader must seek the advice of their physician or other health care provider.