DEAR DR. DONOHUE: You wrote that the causes of one-sided ankle and foot swelling are different from the causes of swelling in both ankles and feet. I am 80 years old and have swelling only of my left ankle and foot. I do not have high blood pressure. In 1993, I had my left kidney removed because of cancer. – S.S.

ANSWER: I did say that, and it was an oversimplification of a complicated process. However, in general, with heart failure, kidney failure, liver disease and a drop in blood proteins, the right and left foot, ankle and leg swell.

Swelling of the foot, ankle and leg on only one side suggests that there is trouble with lymph drainage or lymph nodes, or that there is a leg infection or a clot in a leg vein. Lymph is fluid that comes from the circulation and percolates over tissues to bathe and nourish them. Lymph vessels, open-ended vessels, suction the lymph and return it to circulation. On its return journey, lymph passes through lymph nodes, where foreign material is removed. Disruption of lymph vessels or lymph nodes leads to swelling of the area deprived of those structures. Lymph fluid accumulates there. This often happens after surgery. Breast surgery with removal of lymph nodes and lymph vessels can lead to swelling of the arm on the side of the removed breast. Radiation, infection and trauma are other causes of lymph accumulation. A clot in a leg vein is a common cause of one-sided swelling.

These generalities don’t always hold true. Early heart failure, for instance, can cause one-sided swelling.

The important point is that the cause of any swelling must be found before proper treatment can be given.

FOR READERS: The booklet on gout and pseudogout covers these conditions in depth. Readers can order a copy by writing: Dr. Donohue – No. 302, Box 536475, Orlando, FL 32853-6475. Enclose a check or money order (no cash) for $4.75 U.S./$6 Can. with the recipient’s printed name and address. Please allow four weeks for delivery.

DEAR DR. DONOHUE: Please explain what a silent heart attack is.

If a person fell and hurt his ribs and they were sore for many weeks, could that damage the heart? – V.S.

ANSWER: Heart attacks can happen without any symptoms – silent heart attacks. Such attacks happen more often to people with diabetes, to the elderly and to women. Silent heart attacks are more dangerous than pain-producing heart attacks because people are unaware that they have any trouble. Quite often, the attacks are discovered when an EKG is taken as part of a physical exam. A fall with rib bruises would not create EKG changes of a heart attack, nor would such a fall harm the heart.

DEAR DR. DONOHUE: Our 22-year-old granddaughter has developed an uncontrollable giggle. She giggles before, during and after everything she says. Each time we talk to her, the giggles and their frequency get worse. She is basically shy and appears to be nervous, and says she is not consciously aware of her giggling. She says her friends have remarked on this, too. Is this a tic disorder? Is there something a doctor can do to help her? Is there medication? – S.N.

ANSWER: Underlying anxiety, stress, shyness and social phobia set in motion reflex defenses for people who harbor these traits. It’s their way of coping with situations that generate discomfort. It’s not a tic, although it is somewhat similar. Both are involuntary.

I would first talk to the young lady in a compassionate way and tell her that this behavior is misinterpreted by people and that she should make a conscious effort to suppress the giggling. Only if the giggling cannot be controlled and only if it’s causing her to suffer socially would I turn to medical people for help. Yes, there are treatments and medicines that can control anxiety and phobias, but a trial of self-treatment should come first.

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.