Allergic Living Magazine asked Dr. Hemant Sharma; Allergist, Clinical Researcher and Assistant Professor of Pediatrics, Associate Chief of Division of Allergy and Immunology at Children’s National Medical Center in Washington DC and Director of the Food Allergy Program.
Q: What I don’t understand is: how does an expert decide whether a food allergy is “life-threatening” or not? This issue comes up frequently, such as when preparing forms for daycare or schools.
Dr. Sharma: Your question is a great one because it points out a major limitation of our currently available food allergy tests, and is the reason research is underway to identify more predictive testing.
Unfortunately, neither skin tests nor blood tests for Immunoglobulin E (IgE are the allergic antibodies) can accurately predict how severe a future food allergy reaction might be. For example, even though two people may have the same blood test level to their food allergen, after an accidental exposure, one might have a life-threatening reaction and the other a mild reaction.
Certain people are thought to be at higher risk of a life-threatening reaction; for instance, those with asthma, a previous anaphylactic reaction (the serious form of allergic reaction), or an allergy to peanut, tree nuts or shellfish.
But, food allergy is highly unpredictable, and even people with a mild history can go on to have a life-threatening reaction. At the moment, we have to presume that all food allergies have the potential to be life-threatening and patients should take proper precautions such as reading all food labels and carrying epinephrine auto-injectors.