One in 13 children in the U.S. have a food allergy; that’s roughly 6 million kids. It’s only natural that families with a child who has a food allergy often wonder if a younger sibling should be screened before giving them potentially allergenic foods. But a recent study led by one of our doctors is making families think twice about screening tests.
The study, published in the Journal of Allergy and Clinical Immunology: In Practice, found that screening siblings may be unnecessary. The study shows a high rate of false-positive test results among siblings of children with food allergy. A false-positive is a test result that is incorrect because it shows a condition or finding that does not actually exist.
These misleading test results can lead to stress for families and can prompt them to eliminate foods from a child’s diet that they could potentially be allergic to. Removing foods from children’s diets just out of precaution can actually increase their risk of developing an allergy to that food.
“Our data suggests that the risk of food allergy in siblings of an affected child is only slightly higher than in the general population,” says Ruchi Gupta, MD, MPH, lead author of the study, and pediatrician and researcher at Lurie Children’s. “We also observed that testing might show sensitization to peanuts in a child who has never had peanuts, for example. But that might not mean that eating a peanut will provoke allergic symptoms in that child.” The study found that most siblings (53%) of food allergic children showed food sensitization, but didn’t have allergy symptoms. One-third of siblings tested negative and had no allergic reactions to food. Only 13.6% of siblings had a true food allergy.
“Our findings help support the National Institute of Allergy and Infectious Diseases’ practice guidelines to not screen siblings before the child’s initial exposure to a food,” says Dr. Gupta. “Routine screening without a history of allergic food reactions might lead to unnecessary food avoidance in kids who can actually tolerate that food, which impacts quality of life and nutrition. Food avoidance also increases the risk of developing an allergy to that food.” The study included a total of 1,120 children, including food allergic kids and their biological siblings.
To keep up to date on the latest Food Allergy news from Lurie Children’s, like their Facebook page Allergy & Immunology at Lurie Children’s.
Visit our website to see a graphic that helps explain what every parent should know about kids and food allergy.