DEAR DR. DONOHUE: Could you give me information on Crohn’s disease? I have a 9-year-old niece who is afflicted with it. What kinds of food can she eat? – M.R.

ANSWER: Crohn’s disease peaks between the ages of 15 and 25 and again between 50 and 80. It can, however, happen at any age, and 9 years old is not too young to have it.

It’s an inflammation of the digestive tract that can occur in any section of the tract, from mouth to rectum. Most commonly it affects the ileum, a division of the small intestine and the reason why it is also called regional ileitis. It also frequently affects the colon – the large intestine.

Crampy abdominal pain along with diarrhea that can be bloody are customary symptoms. Patients might also have a fever and complain of extreme fatigue. Weight is lost due to interference with nutrient absorption. With children, that can lead to growth lag.

Sometimes Crohn’s causes problems in places distant from the digestive tract. Some patients have joint swelling and pain. Painful red bumps can break out on the shins. Kidney stones and gallstones can be part of the Crohn’s picture.

Mesalamine is a medicine often used to control Crohn’s. When the illness is quite severe, prednisone — one of the cortisone medicines — can quiet the intestinal inflammation. New medicines such as Remicade can counter the irritating effect of the inflammatory chemicals that Crohn’s disease generates.

Your niece can eat anything she wants so long as it doesn’t cause a flare-up of her illness. That often takes a bit of experimenting to discover. She will need the guidance of a dietitian to ensure that she gets the vitamins and minerals that are often deficient in Crohn’s patients. At some point, she might even require tube feeding – which, when necessary, can be done without greatly interfering with normal life.

DEAR DR. DONOHUE: I had a chest X-ray and was told I had COPD. Big surprise, since I walk almost five miles every day, work out a couple of times a week, ride my bike, cross-country ski and on and on. I am not short of breath at any time, do not wheeze and have no problem breathing. I did smoke for a short time some 30 years ago.

I saw a lung specialist and had breathing tests done. The specialist said I am fine, as are my tests.

However, the X-ray report is disturbing, since it shows scarring, which is called COPD. Will I eventually have symptoms? – E.M.

ANSWER: Emphysema and chronic bronchitis are the two common COPD illnesses. COPD is chronic obstructive pulmonary disease. The diagnosis of COPD is best made with breathing tests. I would put much greater trust in those than in your X-ray. Yours might show only the aftermath of an old infection that will never bother you in the future. Go with the specialist who tells you that you are fine.

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.