Diagnosis Made Easier to Swallow

Researchers develop easy-to-use 'calculator' for diagnosing food allergies

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) Current tests for diagnosing food allergies are costly, time-consuming, and can potentially cause severe reactions. To solve some of these problems, researchers have developed an online tool for diagnosing allergies.

Food allergies among children have become increasingly common in recent years. Consequently, the number of parents looking for diagnoses of their children has also increased. The preferred method of food allergy diagnosis is a double-blind, placebo-controlled food challenge - a test in which patients ingest some foods that might contain an allergen and some that do not. In such tests, neither the doctor nor the patient knows if the food contains a likely allergen.

In addition to concerns of costliness and time consumed, doctors and parents have some fear that these food challenges may trigger a severe allergic reaction (anaphylaxis) during the testing process.

In order to address these concerns, Dr. Audrey DunnGalvin and Professor Jonathon Hourihane, from the Department of Pediatrics and Child Health at University College Cork, designed a mathematical model that would predict specific food allergies, such as those to cow's milk, eggs, and peanuts.

The researchers were able to design their mathematical model by looking at a combination of factors that included outcomes from skin prick tests, allergen specific IgE (an antibody associated with allergies) levels, total IgE levels, history of allergic reaction, sex, and age. Researchers compared these outcomes to results from food challenges. Using this data, DunnGalvin and Hourihane were able to develop a 'calculator' that was more accurate than individual allergy tests.

Normal food allergy tests can be stressful for most young children, says Dr. DunnGalvin. This new calculator will not only reduce the costs of food allergy tests, but it also will improve the quality of life of parents and patients. The new test will allow children to take food challenges when they are slightly older, after the odds of a severe reaction have decreased.

Furthermore, the new calculator will allow doctors to improve oral immunotherapy, a treatment in which doctors give children small doses of a food allergen in order to reduce their sensitivity to that allergen. The calculator will help doctors assess the appropriate moments to continue and stop such treatments.

Kevin Dalton of University College Cork's Office of Technology Transfer says that this new tool will improve the treatment of food allergies among children. He adds that a commercial product should be available to clinicians some time this year, hopefully resulting in improved patient care and significant decreases in health care costs.

Approximately 4 percent of the American population has food allergies. That's more than 12 million people. Food allergies are most common among children. Just eight different foods are responsible for the vast majority (90 percent) of food-allergic reactions. These foods include: milk, eggs, peanuts, tree nuts, wheat, soy, fish, and shellfish.

The only way to prevent an allergic reaction is to steer clear of foods you are allergic to. If it so happens that you come into contact with a food that causes a reaction, there are a couple ways to deal with the reaction. For minor reactions, there are over-the-counter and prescribed antihistamines that can relieve symptoms if taken after exposure. For severe allergic reactions, some people require an emergency injection of epinephrine followed by a trip to the emergency room. If you have severe allergic reactions, your doctor may prescribe an epinephrine auto-injector, such as EpiPen®, Epipen Jr®, and Twinject®.

The research by DunnGalvin and Hourihane is published in the Journal of Allergy and Clinical Immunology.

Reviewed by: 
Review Date: 
March 7, 2011
Last Updated:
March 8, 2011