Escape the pain of food allergy

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NEW LIGHT ON OLD SYMPTOMS The first clue that this might be the case comes from research in children. A unique collaboration between top pediatric allergy and gastrointestinal specialists has turned up compelling evidence in kids that heartburn, nausea, stomach pain, diarrhea, picky eating and other gastrointestinal symptoms are associated with the ingestion of common foods.

Kevin J. Kelly, M.D., who directed the study while at Johns Hopkins Children's Center and is now chief of pediatric gastroenterology at St. Christopher's Hospital for Children in Philadelphia, said he undertook the research because he wanted to find out what was really going on with these children whose symptoms had failed to respond to conventional therapies.

His researchers selected 10 children, ranging in age from 8 months to 12 years. The children shared a similar litany of complaints: frequent diarrhea; frequent vomiting; recurrent abdominal pain; feeling full early and lack of interest in food. In a few cases, the children ate so badly that their physical development lagged.

Based on the children's symptoms and on abnormal cells found on their esophageal biopsies, their doctors had diagnosed them with "gastroesophageal reflux," a very common cause of heartburn.

In reflux, stomach acid bathes and harms the lower end of the esophagus (just above the stomach). The children had been put on standard medications for acid reflux, including H2 blockers and liquid antacids. Six of the children had even undergone one or more operations intended to stop the vomiting. But neither medications nor surgery helped.

Dr. Kelly hypothesized that these children might be experiencing an allergic reaction to certain foods, even though an allergic basis for the chronic symptoms had been investigated. Standard skin-prick allergy testing had been performed, but was negative for most of the children. He came up with a novel way to test his theory. He put them on an amino-acid formula that was completely free of any complex proteins that can trigger allergic responses, but which provided proper amounts of calories and nutrients for healing and growth. The children were also allowed clear liquids and apple- or corn-based foods because they rarely cause allergies. If reflux was the true problem, this new diet would not likely have improved their symptoms.

The results were dramatic. In eight cases, symptoms vanished completely in two to six weeks. The two other children improved substantially in that time (Gastroenterology, November 1995). Microscopic inspection of the abnormal esophageal cells also showed significant improvement.

When normal everyday foods were reintroduced one by one, the children's troubles returned. The link wasn't hard for parents to see: Stomach symptoms and irritability came on rapidly on from 30 minutes to 8 hours after the children ate a particular kind of food. When they looked back, the skin-prick tests were negative for the foods that reproduced the symptoms. (Some of the children had multiple allergies.)

Which foods were most likely to cause problems? Cow's milk was linked to symptoms in seven children; soy, wheat, peanuts or egg was linked to symptoms in two or more children.

Once the offending foods were identified, they were again completely removed from the children's diets. The symptoms went away and stayed away. Except for avoiding the particular food that bothered them, most of the children were able to eat normally. Eight of the children were able to stop taking antireflux medication.

A SMALL LANDMARK Such a small study doesn't prove that food allergies are responsible for most people's symptoms of heartburn and abdominal pain. But it has some doctors considering the possibility-in both adults and children. "I think this research has already improved my ability to practice medicine properly," says Peter Rowe, M.D., a co-author of the study and pediatric diagnostician at Johns Hopkins Children's Center. "Dr. Kelly's study may one day be seen as a landmark. I would say a third of the young patients that I am asked to see have the problem he has defined. They often have been taking drug therapy for years, and now they get rid of their problems in two weeks get rid of a simple restriction of a dietary protein. The improvement is usually quite dramatic, and their families are enormously grateful."

This is a new way of thinking about food allergies. Doctors are familiar with food allergies that trigger immediate anaphylactic reactions. As soon as a patient with a conventional allergy eats an irritating food, she may experience tingling, itching, hives, wheezing, a sense of the throat closing, nausea or vomiting. These anaphylactic reactions are potentially life threatening and can be confirmed by positive skin-prick tests.

But there are other types of allergic reactions, including late-phase responses, delayed-type hypersensitivity and cell mediated immunity. They involve different immune cells, like T lymphocytes. Examples that scientists have long known about include poison-ivy rashes and host-graft reactions after organ transplants.

The fact is, skin tests can't always reveal all true hypersensitivities.

Dr. Kelly believes that the kind of food allergy that these children experience also involves one of these alterative mechanisms. "We don't fully understand it yet, but it may be that esophageal cells are interacting with proteins from the diet and reacting in an allergic way that skin tests can't reveal. We're investigating the possible mechanisms now. But we know there's a long way to go before our allergic hypothesis is proven."

He suspects, though, that many adults have this kind of allergy. "My suspicions are based on the family histories of the children studied."

Dr. Kelly says a major goal of his research is to find out how often children who are suspected of having acid reflux might benefit more from the restriction of certain dietary protein sources than from the use of antacids. He is especially interested in evaluating children for the possibility of food allergy before considering the surgical, treatment for chronic reflux. This might spare children the operation if It is not necessary.

YOUR ACTION PLAN So now what? If you, your spouse or your child Suffers chronic stomach pain, heartburn or nausea and you suspect food allergy, what should you do?

Step one: Rule out the obvious. Many medical conditions can cause gastrointestinal symptoms, including genuine gastroesophageal reflux, obstructions in the upper intestine, bacterial infections related to ulcers, giardiasis (a parasitic infection), Crohn's disease, cystic fibrosis and, particularly in the case of children, Celiac disease, a gluten intolerance. You and your doctor should rule out these more obvious causes first.

In some cases, your doctor may need to perform diagnostic procedure called an upper endoscopy. A lighted tube is inserted through the mouth to see the lining of the esophagus, stomach and duodenum. Your doctor can also collect samples of the living cells. It's a safe outpatient procedure, but the patient must be heavily sedated or anesthetized. Step two: Find Dr. Right. After you've ruled out everything else, consider the food-allergy connection. This means finding a physician who's willing to help you try to test for a food connection. "No one has looked at adult reflux as a possible allergic problem, says Dr. Kelly. "You may have to ask your doctor to begin to consider this approach." Keep in mind that you may need to work closely with this doctor over a long period of time, says Carol Englender, M.D., a board-certified family practice physician in Newton, Massachusetts, who has helped many people implement elimination diets. "You may have to keep coming up with different combinations of food. That can take time.

For a child, Dr. Rowe suggests that parents seek out a pediatric gastroenterologist or a pediatric allergist, who should be familiar with, or open to, Dr. Kelly's work.

If you can't find a physician in your area to help you, an experienced dietitian may be an option. If it's any comfort, Dr. Rowe expects that more doctors will know about this approach in the near future.

Step three: Start by cutting out milk products. In an elimination diet, you remove just one food at a time for several weeks to see what happens. If you have no idea which food might be triggering problems, especially for a child, start by eliminating milk. "Dr. Kelly's work has shown that the vast majority of kids with these problems are allergic to cow's-milk protein," says Dr. Rowe. "So your best bet is to eliminate that one first."

Step four: Be exacting. Whichever food you're eliminating, you must be absolutely scrupulous that there is none left in the diet. Otherwise you may wrongly assume that the food . It's causing the problems. And complete- elimination is not an easy task. fill the case of milk, for example, says Dr. Rowe, "You could take away someone's milk, ice cream and cheese, and still not be completely restricted. A significant portion of the milk we eat is from hidden sources, like baked goods, fillers in processed foods, flavorings and protein-fortified foods." (Oil the other hand, while you are limiting intake of certain foods, you need to be careful not to go overboard and restrict too in much. You still need to ensure adequate nutrition. This is ,mother reason why it's important to work with a physician.) To do the job right, you'll need to start reading labels very carefully. You may have to use fewer processed foods, and do more home cooking. Make this task easier by contacting the Food Allergy Network. This national self-help organization offers a wide variety of invaluable resources, including wallet-sized cards that you can bring to tile Supermarket to help You avoid triggering foods, and cook books. The physicians we interviewed unanimously tell their patients to contact this unique organization for help. For free information, send a self-addressed, stamped envelope to the Food Allergy Network, 10400 Eaton PI., Suite 107, Fairfax, VA 220'

Step five: Wait and see. If you've Completely removed milk for two weeks and see no change 'in symptoms, restore it. (Watch carefully after Von reintroduce the food again for worsening symptoms. Remember, the evidence usually appears within four to eight hours.) If there's no sign of a problem, there's no need to continue I milk. Bring it back. Then go restructuring down the line, removing the next most-common allergens: two weeks without soy. Then try egg, wheat and, finally, I eat peanuts.

If there's still 10 Clue to the cause of symptoms, experiment with restricting other foods. Dr. Kelly's research turned up some rare reactions to foods like sweet potatoes and strawberries in individual cases. If your child improves partially after restriction of a single food, she may be responding to more than one food. Don't start restricting more than one protein Source without help from your doctor or dietitian. If you've identified an allergen, you may see improvement within about two weeks from when VOL] eliminated it.

PHOTO (COLOR): Child throwing nuts into a heart shaped drawing

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