When our food allergy journey started out, one of the most challenging things to wrap my head around was allergy testing. I distinctly remember looking incredulously at our allergist and thinking, “You mean to tell me that a “positive” blood test or that giant hive from a skin prick test doesn’t necessarily mean our son has a REAL food allergy? What good is that?!”
|Two common allergy tests rely on the IgE antibody as a "biomarker." The tips of the IgE antibody recognize specific food proteins, such as those found in a peanut. Blood tests measure the amount of IgE for a specific food that is found in the blood and skin prick tests look for the result of a food protein binding to IgE attached to a mast cell in the skin. The release of histamine (among other chemicals) causes the wheal or hive in a skin prick test. Image source: Atlas of Allergic Diseases|
What I have learned over the course of several years is that there really are no great tests for food allergies – i.e. “biomarkers” –aside from actually consuming the food (oral food challenge supervised by a clinician). The two common current methods of testing - blood tests measuring food-specific blood IgE levels and skin prick tests that scratch the allergen into the skin surface are not a great tests because they frequently give “false positive” results. A “false positive” means that a person may test “positive,” but truly isn’t positive should they actually consume the suspected food. Frustrating. On top of this, most current testing methods that rely on IgE as a “biomarker” cannot predict how severe the allergy is. The only sure way to test for a suspected food allergy is to go to your allergist’s office and perform the supervised oral food challenge – you know, the test where you actually eat the suspected allergen and wait for a response. Having done this with my son several times now, I can’t stress enough just how stressful this stressful test is. There has to be a better “biomarker” – a test without the stress and risk of a reaction that can better predict an allergy and its severity.
|Image source: Selena Bluntzer from Amazing and Atopic|
To help solve this problem, Dr. Xiu-Min Li, Professor of Pediatric Allergy and Immunology at the Icahn School of Medicine at Mount Sinai, and board-certified allergists Dr. Paul Ehrlich and Dr. Purvi Parikh designed a collaborative, practice-based study whose primary objective is to figure out better biomarkers of allergy (details of the study and how you can directly fund the study).