CUSHING'S SYNDROME (ADRENAL CORTICAL HYPERFUNCTION)

The hormones produced by the adrenal glands, as we have noted under Addison's disease, are vital. In Cushing's syndrome, there is overproduction of the hormones and the patient suffers from too much of a good thing. In most cases, Cushing's syndrome results from a diffuse, benign enlargement of the outer portions (cortices) of both adrenal glands.

 In a smaller number, about 15 percent, there is a single, benign tumor in one of the glands which produces the oversupply of hormones. In about 5 percent of cases, there is cancerous enlargement of the cortex of one of the glands.

Typically, a patient with Cushing's syndrome has a rounded face ("moon- face") and a pad of fat in the upper part of the back referred to as a "buffalo hump." There is usually obesity with protuberant abdomen but thin legs. Purplish lines appear in the skin of the abdomen, thighs, and breasts. The skin bruises easily. Excess hair appears on the face. Backache, head- ache, and acne are common. 

Women have little or no menstrual flow; men develop impotence. The doctor finds high blood pressure, a high blood sugar level, and often sugar in the urine suggesting the presence of diabetes-like illness. X-rays show thinning of bones. Other special tests may be used to confirm the diagnosis especially when the disease occurs in mild form without all the characteristic findings.

There is no primary prevention. Secondary prevention of disability and death requires early diagnosis and vigorous treatment. In working up the diagnosis, the physician will try to determine whether the changes in the adrenal glands originate there or may be secondary to over activity of the pituitary gland at the base of the brain. The pituitary produces a hormone that stimulates activity of the adrenal cortex. Sometimes, diffuse enlargement of the adrenal cortices results from over- stimulation by the pituitary. When this is the case, usually there is a tumor of the pituitary gland which can be detected by x-ray. When the pituitary is the cause of the adrenal gland trouble, the condition is called Cushing's disease rather than Cushing's syndrome.

Treatment consists of surgical removal of part of the adrenal gland tissue when there is diffuse enlargement, or removal of the tumor when it is the cause. Only rarely is a cancer of the adrenals found and removed before it has spread to the rest of the body; fortunately, this is an infrequent cause of Cushing's syndrome. When the pituitary gland is involved, irradiation of this gland may be tried alone to observe the effect on the adrenals. 

Sometimes, adrenal surgery must be combined with pituitary irradiation. Rarely, there will be a large pituitary gland tumor that must be surgically removed. Sometimes so much of the adrenal cortex tissue must be removed that the patient goes from hormone over- production to underproduction and is then like a patient with Addison's disease and requires similar treatment.