DEAR DR. DONOHUE: I was told by six different doctors that I had irritable bowel syndrome. Thanks to a determined doctor, I have been diagnosed with celiac disease. How could this have been missed by all those other doctors for all those years? – K.B.

ANSWER: Celiac disease was once considered an exotic disorder but is now becoming a commonly diagnosed illness because of the medical community’s increased awareness of it and of its often-subtle signs. Some investigators say that in a group of 100 people, there will be one person who has celiac disease. That makes it a very prevalent condition. It can come on at any age, but it often does so between the ages of 10 and 30 or when children are first given foods made from grains.

Classic symptoms of it include diarrhea, gas, bloating, abdominal pain and weight loss. All of those can be attributed to many other digestive tract problems, and celiac disease is often erroneously diagnosed as irritable bowel syndrome. That’s not an excuse or an explanation for your plight; it’s a statement of fact.

Frequently, celiac disease does not exhibit the typical features, and that makes the diagnosis even harder to pin down. Celiac patients might not have diarrhea or abdominal pain. They can show up at the doctor’s office with anemia or with osteoporosis due to the inability of their intestines to absorb iron or calcium.

The pathology of celiac disease comes from a small intestine that is irritated by gluten, a protein found in wheat, rye and barley. Celiac patients are sensitive to it. It’s a toxin to their digestive tracts. It inflames them and makes the absorption of nutrients difficult to impossible.

Treatment is the fastidious avoidance of those grains. After about two weeks on a diet free of gluten, 90 percent of celiac patients are feeling markedly improved. A gluten-free diet is something that demands instruction from a dietitian. Gluten is in many products that give no indications they contain it — ketchup, for example.

DEAR DR. DONOHUE: I had been feeling rotten for about 10 days, so I decided to check with my family doctor. He said I had a coxsackie infection. How common is this? I have never heard the word before. – V.M.

ANSWER: Coxsackievirus infections are quite common. Frequently, infection with this virus family produces no symptoms. These infections can also produce a variety of minor symptoms, one of which is the feeling you described. Coxsackieviruses are the viruses chiefly responsible for summer colds.

A fairly common childhood coxsackievirus infection is hand, foot and mouth disease. An infected child breaks out with tiny blisters on the hands, on the feet and inside the mouth. The child refuses to swallow because the throat is so sore. The illness lasts about a week.

Most coxsackie infections, when they do cause symptoms, run a course on their own without need of any special treatment other than trying to make the person more comfortable. There are no specific medicines for an infection.

In exceptional circumstances, coxsackieviruses produce serious illness. They can cause brain inflammation, inflammation of the brain coverings (meningitis) or inflammation of the heart and its coverings. Such infections are treated in the hospital.

DEAR DR. DONOHUE: I am a 38-year-old, healthy male and the father of three children. In the past month I have developed an unbelievable thirst. I drink gallons of water, juice and pop every day. Naturally, I urinate more than usual. What could be causing this terrible thirst? I get up at night to drink. – J.K.

ANSWER: Diabetes immediately springs to mind. There are other thirst-provoking illnesses, but the No. 1 cause is diabetes, and it should be your No. 1 concern. The increased urination is partly due to the fluid you’re drinking, but it’s a sign of diabetes, too. Have you lost any weight? Weight loss is another sign. Get to the doctor quickly.

The diabetes booklet outlines the salient features of this disease. Readers can obtain a copy by writing: Dr. Donohue – No. 402, Box 536475, Orlando, FL 32853-6475. Enclose a check or money order for $4.50 U.S./$6.50 Can. with the recipient’s printed name and address. Please allow four weeks for delivery.

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.