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Food allergies tricky for patients, doctors

Kate Lund broke out in hives on Labor Day weekend in 2007. For the next six months, she was off and on steroids as doctors tried to figure out what was causing the allergic reaction.

"It was really bad," said Kim Lund of Magnolia, Del., mother of the 6-year-old. "It was hard to test her because she was always an active case.

"She would break out head to toe. She looked like a leper," she said.

After keeping a food journal and following a series of trial-and-error tests, they discovered Kate is allergic to sulphites, a preservative often found in canned fish, and fresh grapes and strawberries.

Kate is one of the 6 percent to 8 percent of children who have a food allergy, while only 2 percent to 4 percent of adults are affected, according to WebMD.

A food allergy occurs when the body mistakes an ingredient in food, usually a protein, as harmful and fights it with its immune system. It's not to be confused with the more common food intolerance, which is often dose related, where something in a food irritates the digestive system or causes a person to be unable to properly break down the food.

Dover, Del., allergist Dr. William E. Hermance, FAAAI, said it's difficult to distinguish between the two because symptoms can be similar, which is why people need to come to an allergist.

"The ones you have to watch out for are the actual food allergies," he said, adding, "An allergic reaction can kill a person."

Symptoms of food allergies may include rash or hives, nausea, stomach pain, diarrhea, itchy skin, shortness of breath, chest pain and swelling of the airways to the lungs, depending on the severity. With many of the same symptoms, food intolerances cause nausea, stomach pain, gas, cramps, bloating, vomiting, heartburn, diarrhea and headaches.

If an allergic reaction is bad enough, a patient will go into anaphylactic shock with severe lowering of blood pressure and shock, followed by suffocation from throat swelling.

To prevent this people with severe allergies often carry an auto-injector of epinephrine, which can save their lives until getting to an emergency room.

Discovering the cause

Once someone has had what might be an allergic reaction, an allergist will administer a skin or blood test, Hermance said. The test shows the severity of an allergy on a scale of one to six.

One of the most common misconceptions the board certified allergist said he sees among patients - and even doctors - is what to do with a positive test of seven to nine different foods. Patients can spend a portion of their lives not eating food that doesn't really give them an allergic reaction.

"Food testing is notoriously inaccurate," he said.

In fact, 20 percent of people who test positive won't have another reaction the rest of their lives, but they just have to assume they are allergic because there's no way to tell, Hermance said.

To help counteract inaccuracies, when Hermance gets a large number positive results, he takes all the foods out of a person's diet and then has the patient eat the food, one at a time, in a medical setting so he can treat them if there's a reaction.

"Otherwise they are just sitting around wondering about it or leaving it out of their diet unnecessarily," he said.

However, figuring out what's causing an allergic reaction can be complicated. Hermance often has patients make food diaries of everything they ate over the 24 hours before they had a reaction. This helps him see the timing and also similarities.

"For instance, every time someone eats something red, it may be a reaction to the red dye," Hermance said.

Lund said her daughter was tested for the 20 most common things she ate based on her food diary, but the tests came back negative because she's not allergic to the food itself. Later this year, they will undergo further tests to find out exactly what chemical on strawberries to which her daughter reacts.

"It is so exasperating, but it really boils down to that stupid food diary. You have to write everything down," she said.

Rare cases are hard to figure out. Hermance said he has a patient who is just allergic to blueberries, something he's never heard of before, and another who is allergic to kiwi, lettuce and celery.

Food allergies also can depend on how the food is prepared. Hermance said some people could eat milk, eggs and soy as long as they are cooked because cooking de-natures the protein that causes the allergy.

Lund said the No. 1 thing she's learned is that kids often become allergic to something they expose themselves to, so look first at the things they crave and eat often.

Some patients outgrow their allergies such as with milk or eggs, while others have allergies all their life, such as peanuts and shellfish, Hermance said. Only rarely does an adult grow into an allergy, but it is possible if it's been building up for years, he said.

The eight most common allergens, which must be identified on food labels, are milk, eggs, fish, crustacean shellfish, tree nuts, peanuts, wheat and soybeans, according to the U.S. Food and Drug Administration.

Taking care in schools

Although some sources report food allergies are becoming more common, especially in children, Hermance just believes allergies are better recognized as people become more aware.

Keeping people aware is what area school districts work hard to do.

Wendy Failing, supervisor of child nutrition at Caesar Rodney School District in Delaware, said once parents inform a school nurse, the nurse gives school nutritionists a list of all the allergies. They then put all the information into a computer program so that each time the student inputs their pin number to buy lunch or a snack, the cafeteria personnel will see a list of all allergens.

"If a student has a soy allergy, the manager will go through the food and see what may contain soy," she said, adding then personnel know what the student shouldn't eat.

E-mail Dover Post writer Jayne Gest at jayne.gest@doverpost.com .