ABSTRACT
OBJECTIVE: To reinforce special considerations when offering and conducting oral food challenges (OFCs). DATA SOURCES: Published studies and reviews. STUDY SELECTIONS: Studies concerning OFCs and their conduct. RESULTS: Multiple OFC protocols for various clinical situations and foods were reviewed. CONCLUSION: OFCs are used for the definitive diagnosis of food allergy. Risk and benefit assessment guide the OFC procedure. The conduct of OFCs is influenced by multiple factors, including age, food, and goal of the challenge.
Subject(s)
Food Hypersensitivity/diagnosis , Immunization/methods , Administration, Oral , Age Factors , Allergens/immunology , Animals , Food , Humans , Practice Guidelines as Topic , Risk Assessment , Risk Factors , Skin TestsABSTRACT
BACKGROUND: Egg allergy is one of the most common immunoglobulin E (IgE)-mediated food allergies. Extensively heating egg has been found to decrease its allergenicity and 64% to 84% of children allergic to egg have been found to tolerate baked-egg products. Because there is no reliable method for predicting baked-egg tolerance, oral food challenges remain the gold standard. Prior studies have reported on baked-egg challenges using up to 2.2 g of egg white (EW) protein. OBJECTIVE: To establish whether children with egg allergy would pass a baked-egg challenge to a larger amount of egg protein and the potential criteria for predicting the likelihood of baked-egg tolerance. METHODS: A chart review was conducted of all patients 6 months to 18 years of age with egg allergy who underwent oral baked-egg challenges at Children's Medical Center Dallas over a 2-year period. Challenges were conducted in the clinic with a 3.8-g baked-egg product. RESULTS: Fifty-nine of 94 patients (63%) tolerated the 3.8-g baked-egg product. The presence of asthma (P < .01), EW skin prick test (SPT; P < .01) reactive wheal, and EW-specific IgE level (P = .02) correlated with baked-egg reactivity, whereas ovomucoid-specific IgE level did not. The positive predictive value approached 66% at an EW SPT reactive wheal of 10 mm and 60% for an EW-specific IgE level of 8 kUA/L. CONCLUSION: Most subjects with egg allergy tolerated baked egg. This study is the first to use 3.8 g of EW protein for the challenges. The EW SPT wheal diameter and EW-specific IgE levels were the best predictors of baked-egg tolerance.
