Currently, the only way that people with egg allergies can cope is to avoid yolks and whites altogether. But now, researchers have found that they can eliminate allergic reactions to eggs in some children through the careful administration of powdered egg whites.
Eggs are one of the most common allergy-causing foods. The allergic reaction is most typically caused by a child's immune system overreacting to one of the proteins in egg white, most commonly a protein called ovomucoid. For egg allergy suffers, totally cutting eggs out means avoiding a wide swath of foods from pasta to pastry.
In the New England Journal of Medicine, a group of researchers describe how they conducted a double-blind study with 55 children 5 to 11 years old with egg allergies. The experiment builds on several smaller pilot studies using similar techniques. By the end of the trial, nearly a third of the treated children were able to eat eggs without triggering an allergic reaction.
It's just what we had hoped for, lead author and University of North Carolina researcher Wesley Burks said in a statement Wednesday.
In the current trial, 40 of the children received an oral immunotherapy treatment that involved giving them a small amount of powdered egg whites and gradually ramping up the dosage. Over the course of the study the researchers built the children's doses up to about 2 grams of powder per day, equivalent to about one-third of an egg.
After 10 months, all of the children were given 5 grams of egg-white powder to see if their immune system had adapted. All the children who took the placebo exhibited significant allergic symptoms after this test, while more than half of the treated children did not undergo a significant allergic reaction.
After 22 months, 34 of the treated children were challenged again with 10 grams of egg-white powder. 29 of the children that passed this test then went off treatment for two months, then were challenged again with 10 g of egg-white powder and then ate a cooked egg an hour later.
11 children were able to eat the powder and egg without a serious reaction, and 10 of those were able to eat eggs normally when the researchers followed up with them a year after the trial ended.
Burks cautioned parents against trying their method outside of a clinical setting.
The doses we started on were literally one-ten-thousandth of an egg. It's not feasible to do that at home, Burks said in a phone interview.
This study is not the final phase in developing a treatment. The next step, according to Burks, is a much larger trial with hundreds of children.
Burks took heart at the fact that nearly a third of the children in the study can now enjoy omlettes, soufflés, meringues and other egg-based foods to their hearts' content.
They're eating just like non-allergic kids, he said.
SOURCE: Burks et al. Oral Immunotherapy for Treatment of Egg Allergy in Children. N Engl J Med 367: 233 - 243, 19 July 2012.