Food-induced Anaphylaxis and Oral Allergy Syndrome

1. Priyamvada Tatachar, MBBS* 2. Smita Kumar, MD† 1. *Resident, Department of Pediatrics 2. †Clinical Assistant Professor of Pediatrics, Division of Allergy and Immunology, Kings County Hospital Center and SUNY Downstate Medical Center, Brooklyn, NY After completing this article, readers should be able to: 1. Recognize symptoms of food-induced allergy in general and oral allergy syndrome and anaphylaxis in particular. 2. Know when to refer those who have these problems to an allergist. 3. Discuss how to educate parents about food allergy. A 16-year-old boy presents to the allergy clinic with complaints of perioral itching and tingling after handling apples at his father's fruit stall. He had experienced such symptoms on previous occasions, but this time he has developed mild lip swelling and tongue itching, as well. He has a history of seasonal allergic rhinitis that is controlled by nasal steroid spray. His father is concerned that the reaction might be due to pesticides. A skin prick test with fresh apples gives a positive response that confirms the clinical diagnosis of oral allergy syndrome (OAS). Food allergies are an increasingly common problem faced by pediatricians. Food allergy is defined as an immune-mediated adverse reaction to foods causing symptoms affecting the skin, gastrointestinal (GI) tract, or respiratory system. The reactions can be immune globulin E (IgE)-mediated and nonIgE-mediated processes. Currently, food allergies affect 2% of the general population and 6% to 8% of children. They are most prevalent in the first few postnatal years. Although many children outgrow their food allergies by adulthood, most allergies to peanuts, tree nuts, and seafood are not outgrown. About 35% of children who have moderate-to-severe atopic dermatitis have IgE-mediated food allergies, and about 6% of children who have asthma have food-induced wheezing. The most common food allergens in the pediatric population include cow milk, eggs, peanuts, tree nuts, soy, and wheat; peanuts, tree nuts, fish, and shellfish are implicated most commonly in adults. The human GI tract presents many barriers to ingested immunogenic food proteins. Mucosal-associated secretory IgA, gut-associated lymphoid tissue, gastric acidity, …