DEAR DR. DONOHUE: Will you explain Cushing’s disease? Is there a cure for this disease? – M.B.

ANSWER: The adrenal glands make three important hormones. One is cortisone, without which life cannot be sustained. A second hormone is aldosterone, which regulates the body’s fluid, sodium and potassium levels. Secondary to that action, it is also involved in maintaining blood pressure. The third important adrenal-gland hormone is adrenaline. It gears the body to cope with physical and emotional stress.

Cushing’s disease is an overproduction of adrenal-gland hormones. One result is a redistribution of body fat. Fat is siphoned from the arms and legs and deposited in the trunk and face. The face becomes as round as a full moon. Another consequence of an overabundance of adrenal hormones is skin thinning and bruising. Purple stretch marks appear on the skin. Women sprout facial hair, and their menstrual periods become infrequent and scanty. Men can suffer from erectile dysfunction. Osteoporosis develops in both sexes.

The most frequent cause of Cushing’s disease is a tiny tumor of the pituitary gland, which is located at the base of the brain. This gland secretes a hormone, ACTH, that stimulates the adrenal glands’ production of hormones. The tumor keeps the adrenals producing hormones when they should take a break. Removal of the tumor, which is most frequently done surgically, almost always cures the problem.

In a small number of cases, the problem is an adrenal-gland tumor, usually only in one gland. Removal ends hormone overproduction. In an even smaller number of cases, both adrenal glands have grown too large, and then both glands have to be removed. In those instances, which are few, patients must stay on adrenal-gland-hormone replacement for the rest of their lives.

DEAR DR. DONOHUE: Our daughter has five children, ages 7, 6, 4, 2 and a baby. The 7- and 6-year-olds are girls. All are small for their ages. Their doctor is concerned about this and wants to test their thyroid glands and to check if they are making enough growth hormone. If they aren’t, he wants to give them hormones.

What is the downside of this? – A.C.

ANSWER: If a deficiency of thyroid hormone is the cause of their small stature, then the children must take the hormone in tablet form. It has many actions other than growth, among which is proper brain development. There is no downside to taking thyroid hormone when it’s needed.

Growth hormone is responsible for a child attaining the height that genes have projected for him or her.

If a child is not making enough growth hormone, the medical community would approve of its use.

If a child has a slightly low or normal level of growth hormone but ranks in the lowest percentile of children of the same age in height, then there is a debate about the use of growth hormone. Many pediatricians favor giving it. It produces, on average, at least a 2-inch increase over the height that a child would have attained without having used it. Two inches can make a big difference in a child’s life.

The greatest downside to growth-hormone use is its cost.

In a few children, it upsets blood-sugar control. It has also led to a growth of breast tissue. In an extremely small number, it has inflamed the pancreas. All these side effects are watched for, and appropriate measures are taken if they occur.

The question of leukemia being associated with growth-hormone treatment has been raised, but the association has never been proved.

DEAR DR. DONOHUE: What do you think of a lady, almost 84, having breast reduction due to excruciating back pain? – J.V.

ANSWER: I think a lady of any age whose breasts are so large that they cause back pain deserves consideration for breast-reduction surgery. If the 84-year-old woman is healthy enough to have surgery and if the doctor believes it will relieve her pain, then I would tell her to have it done.

Dr. Donohue regrets that he is unable to answer individual letters, but he will incorporate them in his column whenever possible. Readers may write him or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL 32853-6475. Readers may also order health newsletters from www.rbmamall.com.