Some children with egg allergies may get relief from their symptoms by eating small but increasing doses of egg protein — the very thing they are allergic to, a new study suggests.
The study tested an experimental treatment for food allergies called oral immunotherapy, which aims to gradually desensitize people with food allergies by exposing them to higher and higher doses of the allergen.
By the end of the two-year study, more than half of children with egg allergies who were treated with oral immunotherapy were able to eat 5 grams of egg-white powder and developed only a mild reaction or none at all. All of the children treated with a placebo who ate this amount of egg-white powder developed a significant reaction.
By the end of the two-year study, close to a third (28 percent) of children given oral immunotherapy were considered to be cured of their egg allergy.
The findings are promising, the researchers said, but they cautioned that the therapy is still experimental and should not be tried outside of a research setting.
Oral immunotherapy has previously been found to desensitize some children who have milk and peanut allergies.
Treating egg allergies
By age 3, close to 3 percent of U.S. children have an egg allergy. Symptoms can occur with a single bite of a cooked egg, and range from mild, such as hives, to severe, such as trouble breathing and a drop in blood pressure.
Most children outgrow their egg allergies, but those who still have reactions at age 5 are unlikely to outgrow them in the next several years, said study researcher Dr. A. Wesley Burks, chair of the pediatrics department at the University of North Carolina, Chapel Hill.
Currently, the only way for allergic people to avoid reactions is to steer clear of the food, but this can be difficult because many products contain eggs, according to the Mayo Clinic.
The new study involved 55 children with egg allergies between ages 5 and 18. Forty of the participants were assigned to receive oral immunotherapy, and 15 to receive a cornstarch placebo.
After 10 months, all participants were "challenged" to see how they did after eating 5 grams of egg-white powder. Twenty-two participants on oral immunotherapy (55 percent) passed the challenge, while none treated with the placebo did.
After 22 months, 34 of the participants in the oral immunotherapy group were given a second challenge of 10 grams of egg-white powder, and 30 participants (75 percent) passed. Those who passed were then taken off of immunotherapy for four to six weeks to determine if the beneficial effects of the treatment would continue.
After 24 months, 11 children were able to eat the equivalent of a large egg without any symptoms.
While not all children were cured by the treatment, the researchers said that even some desensitization is important, because it could prevent a severe allergic reaction should the child be accidentally exposed to egg.
It's possible that some children who seemed "cured" of their allergy simply outgrew it, but this is unlikely, the researchers said, because the study included only children with a low likelihood of outgrowing their allergy.
Further research is needed to identify people who are most likely to respond to oral immunotherapy, and the best doses to use, the researchers said.
The new study will be published Thursday (July 19) in the New England Journal of Medicine.
Pass it on: Oral immunotherapy may help children with egg allergies.