Everything you need to know about an egg allergy

Egg is one of the most common food allergies in childhood, and it’s also the most likely to be outgrown. Here are all your questions answered.

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Eggs make an easy breakfast—and lunch and dinner. They’re perfect for those days when you don’t have a ton of time to cook but want to make sure that your kid still eats a healthy meal packed with protein and vitamins. But if your child has an egg allergy, not only is this simple meal off the menu but you may also have to avoid a long list of egg-containing foods, from baby food to baked goods. The good news is that some allergic children can tolerate egg when it’s baked, and egg is the most likely food allergy to be outgrown. Here’s what you need to know if your child is allergic to egg.

What is an egg allergy?

An egg allergy occurs when the immune system mistakenly identifies one or more of the proteins in egg as harmful and mounts an attack, releasing chemicals that cause an allergic reaction. Egg contains several proteins in the yoke and white, and kids may only be allergic to certain ones. “The most allergenic part of the egg is the white, and it causes more serious symptoms,” says Maria Triassi Asper, an allergist at The Hospital for Sick Children in Toronto.

The majority of kids (80 to 85 percent) won’t react to egg when it’s baked in foods, such as muffins and cookies, rather than lightly cooked in scrambled eggs and pancakes. “There’s something about egg being mixed with flour and baked in the oven that changes the protein, so the body doesn’t recognize it and tolerates it,” explains Triassi Asper.

(Technically, the egg-and-flour combination has to be baked at 350 degrees celsius for 30 minutes minimum for the egg protein to change so the immune system doesn’t recognize the egg in the same way and it can become tolerable.)

A well-cooked egg, like a hard-boiled egg, may also cause a less severe reaction than a soft-boiled egg. However, if a child is allergic to a heat-resistant protein in the egg white, the cooking method won’t make a difference.

How common is an egg allergy?

Egg is one of the most common food allergies in childhood, affecting about two percent of kids and typically showing up the first time they knowingly eat it. However, to become allergic to egg, a child must first be exposed to it in some way, by unknowingly eating trace amounts or coming in contact through broken skin (such as eczema). It’s extremely rare for a breastfed baby to be exposed to enough protein in their mother’s milk to have an allergic reaction.

mom hugs daughter turned away from camera at the doctors office How to prepare for an allergist appointmentFood allergies have increased in children over the past few decades, although no one knows exactly why. There are a number of theories, including the possibility that highly allergenic foods are introduced too late in life. Today, parents are urged to introduce egg and other highly allergenic foods, such as peanuts and sesame, by six months of age to help reduce the chances of developing an allergy. “The best way to have an influence on preventing food allergies is early introduction,” says Triassi Asper.

What are the symptoms of an egg allergy?

Symptoms of an egg allergy typically set in soon after exposure and can involve the skin and respiratory, gastrointestinal and cardiovascular systems. The most common symptom of an egg allergy is hives, which is experienced by more than 80 percent of children, followed by vomiting, says Triassi Asper.

Egg can cause anaphylaxis, a life-threatening allergic reaction, but death is rare. A German survey found that seven percent of severe anaphylactic reactions among children are caused by egg.

Anaphylaxis typically comes on quickly and involves two or more body systems, including the cardiovascular or respiratory system. The most serious symptoms of anaphylaxis are difficulty breathing and a drop in blood pressure, which can cause children to lose colour, become light-headed or dizzy, feel irritable or drowsy and even pass out.

Triassi Asper advises parents to be on the lookout for all of the possible symptoms because reactions may be different each time. “They can vary, depending on what the food is, how it is prepared and even the circumstances of the child,” she says. “If a child is sick or eats an allergenic food and then exercises, the reaction can be more severe.” It’s not known why illness and exercise can intensify a reaction, but it may have to do with physiological processes that modify the digestion, absorption and distribution of food.

How do you treat an egg allergy? 

If you suspect that your child is having a mild allergic reaction to egg for the first time, such as itchiness inside the mouth, you should take them to the doctor as soon as possible. If the reaction progresses or involves more than one mild symptom, you should call 911.

At the hospital, your child will be assessed and may be treated with epinephrine, a life-saving drug that stops the reaction. They may also be treated with other medications, such as steroids and antihistamines  (given by puffers or masks), to ease symptoms like hives and wheezing.

Once your child has been diagnosed with an egg allergy, they will be prescribed an epinephrine auto-injector (called by the brand name EpiPen in Canada). You and anyone who takes care of your child should always have it on hand in case of accidental exposure.

If your child accidentally eats egg and has a severe reaction, Triassi Asper recommends administering epinephrine immediately. But if a child only has one symptom, such as hives, you can wait and see how the reaction progresses. However, if the reaction progresses or if a second symptom shows up, an epinephrine auto-injector needs to be administered.

“If there’s any doubt in your mind about treatment, you should be giving them the auto-injector,” says Triassi Asper. “We know that delaying treatment with epinephrine can lead to a higher incidence of death and poor outcomes.” If a reaction doesn’t progress beyond one symptom and your child is uncomfortable, Triassi Asper says that you can give them an antihistamine.

Is there a cure for an egg allergy?

While there is no cure for an egg allergy, oral immunotherapy, which involves gradually increasing daily doses of an allergen to build up tolerance, is at the experimental stage for egg, and parents typically have to pay out of pocket because it’s not covered by provincial healthcare plans. Studies show that oral immunotherapy may help most children tolerate a small serving of egg if they continue to consume a daily dose of egg protein, but more research is needed. Triassi Asper says that oral immunotherapy may reduce the likelihood of anaphylaxis, but the child will still be allergic.

“It’s not a cure,” she says. “The child is eating what they’re allergic to, so sometimes there are side effects of the treatment as well. The only fully accepted treatment is avoidance.”

How do you diagnose an egg allergy?

If you suspect that your child has an egg allergy, you should get a referral to an allergist, who can do a skin prick test, a blood test or both to confirm the diagnosis. The skin prick test involves exposing the skin to the allergen and seeing how big of a weal (an area of irritated skin) develops. The larger the area of irritated skin, the more likely it is that they’re allergic.

When Triassi Asper sees kids who have reacted to eggs on their own but not in baked goods, she encourages them to continue eating baked products. Tolerating egg in baked goods is an important indicator of whether a child is likely to outgrow an egg allergy altogether but she says research does not yet clearly show that regular consumption of baked egg speeds up tolerance.

If they haven’t tried baked goods, she will do a blood test to see if they might be able to tolerate the protein that doesn’t change when baked. If chances are good, she will do an oral food challenge, which involves baking a muffin using a standard recipe and then bringing it to the doctor’s office for the child to consume under supervision.

What foods should your child avoid if your child has an egg allergy?

Once you know the extent of your child’s allergy, you can avoid the foods that trigger it. Egg can be found in a wide variety of processed foods, including breads, pastas and soups. It can even show up in egg substitutes, so it’s important to read product labels carefully. In Canada, products that contain egg must be clearly labelled. However, precautionary labels that warn of potential cross-contamination with egg are voluntary in Canada, so contact the company if you’re worried about a particular product.

Some children who are allergic to chicken eggs are allergic to other bird eggs, such as duck, goose and quail, and a smaller number are also allergic to chicken meat. If your child is allergic to egg, watch them closely when they consume these foods and be ready for a reaction. In addition to foods, egg can also be found in craft materials, such as paints, and hair products.

Egg allergy and vaccines

Some vaccines and medications contain egg, too, so it’s important to check with your doctor or pharmacist. In the past, some flu vaccines were considered unsafe for those with egg allergies, but that is no longer the case. The yellow fever vaccine is now the only one that can cause a reaction in people with an egg allergy, says Triassi Asper.

Can an egg allergy be outgrown?

Egg is the most likely childhood food allergy to be outgrown, but estimates vary. A 2007 study found that four percent develop tolerance by age four, 12 percent by six, 37 percent by 10 and 68 percent by 16. Triassi Asper says up to 80 percent of children eventually outgrow the allergy.

Meanwhile, an Australian study published in 2014 found that the allergy resolved itself in 47 percent of children by age two. The 2014 study also found that children who can tolerate baked egg are much more likely to outgrow the allergy by age two than those who can’t tolerate it—56 percent compared to 13 percent—and their chances are even better if they eat baked egg regularly. “Over time, your body can build a tolerance to egg if you are exposed through baked goods,” says Triassi Asper.

Parenting a kid with an egg allergy

New parents Taira Poletz and Jesse Bedard were relaxing on the couch after putting their 11-month-old son, Jackson, to bed when movement on the baby monitor caught their attention. Jackson, who was lying on his back in the crib, was projectile vomiting straight up in the air after eating egg for dinner. His parents rushed in, cleaned him up and monitored him closely for the rest of the night. Jackson saw an allergist, who advised the family to keep eggs off the table—for now.

“His recommendation was to avoid eggs for the time being,” says Poletz. “He said it could get worse, as this was the initial reaction, and the next time it could be deadly. Eggs are in everything and a good source of protein, so it’s stressful for parents.”

Poletz, who loves eggs, kept them out of the house and only indulged in her beloved eggs Benny when she went out for brunch sans kid. Her son’s preschool also banned eggs in the daily shared snacks that families took turns supplying. Shopping became even more of a chore than usual. “You really have to read labels,” says Poletz. “I used egg replacement and made everything at home—you just learn to work around it.

When Jackson was four, he did an oral food challenge under the supervision of his allergist and didn’t have a reaction. “I’m really glad he outgrew it,” says Poletz. “Now, crispy eggs are one of his favourite breakfasts.”

 Read more:
Your guide to life after a food allergy diagnosis
When your child’s food allergy leads to anxiety

 

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