Peanuts, shellfish, milk and soy: some people canít have a taste of these items without having severe allergic reactions. But itís unknown why many patients react the way they do and how severe their reaction can be.
During National Food Allergy Awareness Week, UC volunteer assistant professor of clinical otolaryngology Steve Sutton, MD, says thereís still much to learn about food allergies and why they affect some people more than others.
Though food allergy testing can carry the risk of false positives, and should be interpreted by an allergist, research has demonstrated an overall increase in the prevalence of food allergies in recent decades. Self-reported survey data in the U.S. suggests an 18 percent increase in food or digestive allergies from 1997 to 2007. Other surveys found notable increases in pediatric allergies to tree nuts and peanut allergies.
With this increase, Sutton says the field needs testing that can determine the exact nature of a patientís allergy.
"Our most available testing, a skin test or blood test, isnít able to tell patients whether they have a life-threatening reaction or a mild reaction to the food,Ē he says. "Only exposure can tell you that, but that can be dangerous when not done in the right setting.Ē
To test with exposure, Sutton recommends an "oral challenge,Ē in which patients, supervised by a trained physician, are given increasing amounts of a suspected allergen until they have a reaction or tolerate a normal serving.
"Youíd be surprised at the number of people you expect to pass the challenge and donítóor vice versa,Ē he says.
That unknown factor in food allergies is what Sutton believes should be the focus of future research into allergies and immunology.
"Our biggest issue is the need to have some sort of testing or biomarker that would track, not only what the individual is truly allergic to, but to what extent,Ē he says.
He says there are now blood tests for peanut and a few other allergens that can identify what protein leads to the individualís allergic reaction. These tests may be useful in predicting whether a patient is allergic to a protein that tracks with a more severe type of reaction or whether the patient is allergic to a protein that is less problematic. However, more research is necessary to understand how to make full use of these newer studies.
"As food allergies become more prevalent, patients are rightly insisting on adequate safety, better testing and research results that lead toward curing this problem or at least making it less burdensome,Ē says Sutton.
Until those goals are met, Sutton is working with the patient community to advance awareness. On April 28, he served as honorary medical chair of the Food Allergy & Anaphylaxis Networkís Walk for Food Allergy in Cincinnati, held at the Theodore M. Berry International Friendship Park.
The groupís fundraising goal for the event was $25,000óit raised more than $54,000.
"We have a long way to go,Ē Sutton adds, "but we will get the answers we want because of the drive of the food allergy community.Ē