DEAR DR. DONOHUE: We have a grandson who recently turned 6 years old. He is pretty much normal in height, but he weighs only 35 pounds. I am very concerned. As a baby, he ate formula and was a good size. When he started eating solid foods, he became thinner. He should eat more vegetables and fruits. He wears short pants for a 2-year-old, and they are big in the waist. He is bright and has lots of energy. His pediatrician said he’s low on the growth chart, but he didn’t suggest anything. What is your opinion? – D.W.

ANSWER: Between the ages of 2 and 5, children, on average, gain 4.5 pounds (2.2 kg) a year. From 6 to 12, they put on about 7 pounds a year.

On weight charts for age, your grandson is in the lowest 5th percentile. That means 95 percent of children his age weigh more than he does.

About one in five kids is a picky eater, but even picky eaters moderate their food intake to meet the needs of growth and activity. Almost all grow out of it. The boy’s height is average, and that’s good. His weight isn’t. If other indicators of growth show lagging development, then I would be worried along with you.

Have his parents ask the pediatrician for a few lab tests. Checking for anemia should be one of those tests.

Tell his parents not to badger him about eating. Gentle prodding to entice him to try small samples of a variety of foods won’t hurt him. Have his parents also ask the doctor if this child would benefit from a multivitamin. It’s hard to believe he’s getting enough vitamins and minerals, including calcium, with his weight as low as it is.

DEAR DR. DONOHUE: I hope you can help me. My wife suffers from a Baker’s cyst behind her knee. When she walks, the pain lessens. In bed, it gets worse. – G.S.

ANSWER: Your wife has to have this diagnosis confirmed. Other things look like a Baker’s cyst, and they call for different treatment. I can’t explain why she has more pain in bed than she does when walking.

A Baker’s cyst is a behind-the-knee swelling. Actually, it’s a bursa filled with fluid. A bursa is a flat, soft disc situated between tendons and bones to reduce friction when tendons rub against bones. Most often, when a person develops a Baker’s cyst, something has gone wrong in the knee joint. The knee has a direct communication with the bursa behind it. When there’s too much joint fluid, the fluid drains into the bursa and causes it to swell. Arthritis of the knee is one of the causes for such swelling.

Rest and anti-inflammatory medicines like ibuprofen can often diminish the size of a Baker’s cyst. If they cannot, then a doctor can drain the cyst with a needle and syringe and, at the same time, instill cortisone into the bursa to prevent it from accumulating fluid again.

DEAR DR. DONOHUE: I recently read that nausea and gas are symptoms of pancreatic cancer. I have both. Could I have pancreatic cancer? I am 79. – E.B.

ANSWER: Pancreatic cancer’s average age of onset is 65. The risk of coming down with it increases with age. About 34,000 new cases of it occur yearly in the United States. It is the fourth leading cause of cancer deaths.

What makes pancreatic cancer such a peril is its lack of signs and symptoms in its early stages. Symptoms, when they do arise, include loss of appetite, a drop in weight, stomach discomfort or pain, nausea, and a sensation of fullness after taking only a few bites of food. As the cancer grows, it blocks the drainage of bile, and the skin and whites of the eyes turn yellow.

Your symptoms are common to many things, and pancreatic cancer is not high on the list. However, I have learned one thing about medicine. When a person brings up a diagnosis, I can’t dismiss it, no matter how remote the chances of having it are. See your doctor. You and I will sleep better if you do.

DEAR DR. DONOHUE: I work with a young man who has AIDS. He’s the picture of health. I wouldn’t suspect he was sick, and I found out only because he told me. I have grown very fond of him. He’s an excellent worker. What’s his life expectancy? – S.J.

ANSWER: This year marks the 25th year that AIDS has been a health issue in North America. In the early days of the AIDS epidemic, it was a death sentence, and death came fairly rapidly after the diagnosis was made. Since then, it has become a treatable, chronic illness. Although treatment doesn’t eliminate the virus, it allows most to live long, energetic, productive and happy lives. I can’t give you an exact life-expectancy figure.

The transformation of AIDS into a treatable disease occurred in the late 1990s, with the advent of HAART (highly active anti-retroviral therapy). The AIDS virus (HIV, human immunodeficiency virus) is a retrovirus.

HAART consists of three and sometimes four drugs that are effective in suppressing viral multiplication and restoring the immune system. Once the immune system begins to function, AIDS patients are no longer under the threat of contracting unusual germs that are difficult to treat and that used to lead to early death. A robust immune system also protects against AIDS-related cancers, another factor in the early death of AIDS patients.

Formerly, AIDS treatment involved a complicated schedule with many pills taken many times a day and often timed to when food was taken. Now there is a single medicine with three drugs, and it needs to be taken only once a day.

AIDS remains a deadly disease, one that can cause great suffering. Some of its fearsomeness has been tempered by new treatments, but it is still an incurable illness. What is needed is medicine that completely wipes out the AIDS virus and a vaccine that prevents infection. Worldwide, there are about 40 million people infected with AIDS, 4 million new cases every year and 2.8 million deaths annually.

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.

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