When Food Causes Reactions: Answers to Questions about Food Allergies in Children

Today, more and more infants and children are being diagnosed with asthma, eczema and allergies. Food allergies are of particular concern, because the reactions can be severe and may even be fatal. One in 13 children have food allergies and that number is increasing. Dr. Susan Schuval talks about the rising incidence of food allergies in children, and what parents need to know.

What are typical food allergies in children?
The most common food allergens in children are milk, egg, soy and wheat. Infants may have problems with milk and formula; they may exhibit vomiting, rash or wheezing. Parents often try switching formulas, but the babies continue to have reactions. When these infants come to the Pediatric Allergy Clinic for testing, we often find out they have a milk or soy allergy.  Egg allergy is also common in young children. It is important to diagnose egg allergy early on because the MMR (measles, mumps and rubella) and influenza vaccines contain egg. In the case of egg allergy, these vaccines may be given, but with caution in case of allergic reaction.
Older children may have hives, wheezing, eczema, swelling, and even anaphylaxis (the most severe allergic reaction that involves multiple organ systems), which can be deadly. We see children with anaphylactic reactions to all kinds of foods, especially tree nuts and peanuts.

How do you test for allergies?
There are a few ways. We can do prick skin testing in the clinic, which is easy and quick. Another option is ImmunoCAP blood testing. They both test for the same thing: the allergic antibodies to food or environmental allergens.
The best way to tell if a child has outgrown a food allergy is to do a test called an oral challenge. Patients come into the clinic, and we cautiously give them the suspected food allergen, in increasing amounts over a three-to-four-hour hour period with close observation, to see if they still have a reaction. This test may be necessary because a patient may have a negative blood test and a negative skin test to a food allergen but still have a positive oral challenge.

When should a child see an allergist?
Anyone who’s had a severe allergic reaction in the past, certainly an anaphylactic reaction, should see an allergist. Children who have family members with sever food allergies should also see an allergist. Other indications for allergy testing include eczema, hives, or angioedema (swelling).
Of course, if you think your child is having an anaphylactic reaction, you should call 911 and go to your nearest hospital emergency room. For less severe reactions, like hives, antihistamines such as diphenhydramine are usually given.

What is the treatment for food allergies?
There is no cure for food allergy. The treatment is to strictly avoid the food trigger. This may involve reading labels on foods and exercising extreme caution outside the home, especially in restaurants.  If a child has had a severe reaction, the parents should have an adrenaline autoinjector such as the EpiPen or AUVI Q. These medications are used to treat life-threatening allergic reactions. Certain children over 12 years of age may be taught to use their own EpiPen.
There have been recent trials of food immunotherapy. These involve giving the children increasing amounts of milk, egg or peanut over time in a controlled environment to induce tolerance to the food. These studies have shown that this treatment may help some children to overcome their food allergies. This is something that we might be doing in the future, but it’s not the standard of care at the present time.
Another recent study that received a lot of attention was the LEAP (Learning Early About Peanut) study.  This study showed that early administration of peanut to young infants may prevent the development of peanut allergy.
The good news is, very young children will often outgrow milk, egg, soy and wheat allergies. Older children and adults, who have allergies to peanuts, tree nuts, fish and shellfish, are less likely to outgrow these allergies. We do see these children yearly however, as one in five children will outgrow a peanut allergy and one in ten children will outgrow a tree nut allergy over time.

Why should a parent take their child to the Stony Brook Children’s Pediatric Allergy Clinic?
We are an academic medical center on the cutting edge of recent advances in allergy diagnosis and treatment.  Our Allergy/Immunology team includes two board-certified pediatric allergists/immunologists and a certified pediatric nurse practitioner/nurse educator, all of whom have many years of experience treating children with allergies.   We offer all the different types of allergy testing and focus on patient education at every visit. We teach s our patients to identify their food allergy triggers, and teach them how to avoid them, in order to prevent reactions.

Learn more at stonybrookchildrens.org or call (631) 444-KIDS.