Food Allergen Immunotherapy in Preschool Children: Do We Have the Evidence?

Standard care for the management of food allergies previously centered on allergen avoidance and the treatment of adverse reactions after allergen exposure. An increase in the development of immunotherapy treatments for food allergy has occurred over the past 2 decades, with many centers now offering immunotherapy. Previous studies mainly focused on school-age children in whom food allergies are likely to be persistent. However, there is increasing evidence that delivering immunotherapy for food allergy to preschool-age children may deliver higher rates of success, and that peanut allergen immunotherapy leads the way. Conversely, the natural resolution of food allergies occurs primarily in these younger age groups, resulting in challenges to selecting patients who will ultimately benefit from these treatments. Both immunotherapy and natural history studies reveal the inherent plasticity of the immune system in early life, which may be more amenable to intervention, but this raises a delicate yet unknown balance between the optimal timing of intervention versus waiting for natural resolution of the food allergy. Here we review the evidence for early food allergen immunotherapy in preschoolers, and present the pros and cons of this approach while acknowledging important research gaps in this age group.