Imagine being told your baby had a formula allergy (nope), a goat’s milk allergy (nope), a coconut allergy (nope), and a cow’s milk allergy (nope), and then finding out that in fact they didn’t have any food allergies at all?
That’s exactly what happened to a 15-month-old girl who suffered from a rash and vomiting. It was only through sophisticated testing that she was found to have no food allergies. Zero. Her issues had been caused by run-of-the-mill ailments, and she left the hospital without a single food restriction.
So why did this toddler receive an incorrect food allergy diagnosis over and over? The trouble was the skin-prick allergy tests, which haven’t changed much in 20 years. According to Scientific American, skin-prick tests produce signs of irritation 50-60 percent of the time, even when the person is not actually allergic. False positives happen ALL of the time. Whaaaaaat?
Of course, food allergies are extremely serious and can be life-threatening. But it’s also problematic to tell someone they have an allergy when they do not.
Kids who believe they have a food allergy report higher levels of stress and anxiety (so do their parents). Sometimes they have to eat away from their friends. It’s worrisome to fly on an airplane. navigate a class party, take in a baseball game, head to summer camp, or even attend a playdate or a birthday party. It’s expensive to keep two epinephrine injectors with your child at home, at school, at a babysitter’s, etc., not to mention the time parents need to take off from work. It can be hard on siblings without allergies who feel their brother or sister is getting more attention or preventing the family from going out for ice cream sundaes.
So which tests are more accurate than the skin-prick?
Experts say the ideal test for food allergies is a placebo-controlled taste test, where the person is given a potential allergen (eggs baked into a slice of cake) as well as something innocent that looks the same (an egg-free slice of cake), and their body’s response to each food is compared. Pediatric allergist John Lee, director of the Food Allergy Program at Boston Children’s Hospital, says this test is 95 percent accurate but it’s also risky, time-consuming and expensive.
A promising option is the basophil-activation test (BAT) that involves mixing a drop of a person’s blood with the potential allergen and measuring the reaction in basophils (a type of white blood cell). It also earned a 95 percent success rate in the pilot studies, and it’s still in the research phases.
Allergen-component testing has been approved for peanut allergies and challenges peanuts with specific nut proteins rather than a mixture of all nut proteins. It’s helping doctors determine if a person is really allergic to peanuts or just reacting to a single protein within them. An anti-IgE drug that prevents an allergic reaction is being tested now.