We recently found out that my 2-year-old boy gets some sort of rash when he touches raw eggs, but we’ve fed him eggs before and don’t seem to have any problem. Should we continue giving him eggs? Is it safe?

Reactions to eggs can occur in many different forms. The most common reaction is a food allergy, in which eating eggs can lead to an allergic reaction such as hives (urticaria), swelling around lips and eyes, vomiting, and shortness of breath. Severe allergic reactions called anaphylaxis can be fatal when appropriate medical interventions such as using an Epipen (auto-injectable adrenaline) are not done.

In this described instance, the child can eat cooked egg but only gets a rash when in contact with raw egg. The contact rash is called contact urticaria, in which the skin rapidly develops an itchy rash upon contact with the offending allergen. This unique situation occurs because the allergenicity of eggs changes from being the most allergic in the raw form and the least allergenic in the cooked form. The process of using heat to cook the egg denatures and changes the protein structure thus making the egg less allergenic.

The child can continue to eat fully cooked eggs but has to avoid eggs that are partially cooked. A lot of parents are unaware that partially cooked eggs include kaya and that certain ice creams and mayonnaise contains raw eggs! An egg-allergic child that eats these raw or partially cooked eggs can develop a more severe allergic reaction.

I recommend that parents who suspect that their child may have food allergies bring their child for proper evaluation by a trained allergy specialist. An allergy specialist will conduct a thorough history and physical examination to determine if there is an allergy. If there is suspicion of allergy, a painless procedure called a skin prick test can be done. This procedure consists of a small scratch of an allergen onto the surface of the skin and the results can be obtained within 15 minutes. A positive reaction appears like a mosquito bite from the skin prick test and tells us that there is an allergic sensitization to the suspected allergen. Through skin prick testing, the allergist can monitor when the food allergy has been outgrown and the food can be introduced in a medical setting to confirm that the allergy has resolved.

It is not recommended for parents to obtain food allergy testing on numerous panels of foods and to seek invalidated experimental food allergy tests. These tests are seldom helpful and even worse, cause unwarranted food avoidance that can cause malnutrition in the child. Through a proper evaluation by an allergy specialist, food allergies can be diagnosed accurately and correctly managed. With proper management, some food allergies such as cow milk and egg allergies can be outgrown over time. There are new and upcoming treatments that are being developed to treat food allergies. Among them, food immunotherapy has shown good promise in helping patients with food allergies.

By

Dr Kent Woo

Allergy & Immunologist