Should younger siblings of children with food allergies be tested for allergy to foods even if they haven’t shown symptoms? A study published in the Journal of Allergy and Clinical Immunology: In Practice suggests such testing may be unwarranted.
“Our data suggests that the risk of food allergy in siblings of an affected child is only minimally higher than in the general population,” says lead author Ruchi Gupta, MD, MPH, pediatrician and researcher at Ann & Robert H. Lurie Children’s Hospital of Chicago and Associate Professor of Pediatrics and Medicine at Northwestern University Feinberg School of Medicine. “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 looked at a population of 1,120 children comprised of those with food allergies and their biological siblings, in which food allergy status was determined from data derived from interviews and results of IgE and skin prick testing. One third of the siblings tested negative and showed no reactions to food and 53% of siblings showed food sensitization with testing but did not experience food allergy symptoms. Only 13.6% of siblings had 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 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.”