Q. About 10 years ago I developed what was diagnosed as gynecomastia. What is the cause of this breast enlargement in males, and should I be concerned to still have it so many years later? A. Breast enlargement in males, known as gynecomastia, is fairly common and not usually serious. (Gyneco means woman and mastia means breast.) In most cases, its major effect is to produce anxiety about self-image. It generally has different causes depending on the age when it occurs.

About 70 percent of baby boys have some degree of breast enlargement, an effect of their mothers' hormones. In many of these infants, a fluid, sometimes called "witch's milk," can be squeezed out of them.

Most adolescent boys develop a slight amount of breast enlargement as part of puberty, but in some it can be marked. Sometimes the increase in size may occur in one breast only. In the vast majority of boys, the breast returns to normal size.

Many elderly men develop gynecomastia in response to changing levels of hormones.

In the examples I just mentioned, gynecomastia occurs almost as a normal part of development at different ages. But there is also a long list of diseases and conditions that can cause breast enlargement in males: testicle problems, including tumors; hormone imbalances, including problems with the thyroid, adrenal or pituitary glands; liver disease, such as cirrhosis; kidney failure, especially in people on dialysis; side effects of many medications, including Aldactone, Aldomet, digoxin, Dilantin, estrogens, INH, reserpine, Tagamet, and Thorazine; smoking marijuana.

Because so many disorders can cause gynecomastia, it's important to have a thorough examination to make sure you don't have an underlying problem. Conditions that can look like gynecomastia include obesity and breast cancer, which occurs rarely in men.

Once the male breast stays enlarged for more than a year or so, it tends to persist. Assuming you don't have any signs of an underlying condition, it's unlikely that you need to be concerned with anything other than its cosmetic appearance. Although doctors have tried some medications to treat this condition, severe, persistent cases usually require surgery to remove the excess growth. Fortunately, this is the exception rather than the rule.

Q. Are doctors supposed to wash their hands before handling infants? I ask because this used to be standard practice when I took my children to the doctor many years ago, but I don't see it being done with my grandchildren.

A. Regular handwashing is important in preventing spread of infection in children and adults in hospitals, but it's not clear how important it is in office practice.

It certainly makes sense for doctors to wash their hands after examining a patient with an infection, particularly skin infections, respiratory infections like colds and sore throats, diarrhea, and viral infections like pink eye and hepatitis.

Guidelines published by the American Academy of Pediatrics call for regular handwashing by health workers taking care of hospitalized children, especially infants in a nursery. But the guidelines say that handwashing may not be necessary before brief contacts with adult patients.

I'm not aware of any official recommendations calling for doctors to wash their hands before examining children in their office, although common sense would say this is sound practice. If it bothers you that your doctor doesn't do it, I think a simple request would be all that's necessary to get the message across. Follow-Up: Sjogren's Syndrome

In response to my answer about Sjogren's syndrome, two readers wrote in the hope that this condition could receive more attention. They point out that the severe form of the disease can be quite debilitating, and that there is a national Sjogren's Syndrome Foundation with a local support group for people suffering from this disorder.

The national Foundation's address is 29 Gateway Dr., Great Neck, N.Y. 11021. You can get more information about Sjogren's syndrome from the local support group representative, Mary Dunphy, 7801 Mandan Rd. No. 203, Greenbelt, Md. 20770, 474-1062. $90;By Dr. Jay Siwek; Jay Siwek, a family physician from Georgetown University, practices at the Fort Lincoln Family Medicine Center in Northeast Washington.