Is it possible to predict the development of anaphylaxis before oral food challenge tests administered to evaluate tolerance in IgE-mediated food allergy in children?

Objective: Life-threatening anaphylaxis may occur in IgE-mediated food allergy. Oral Food Challenge (OFC) is the gold standard in demonstrating tolerance and diagnosing food allergy; however, these tests may cause anaphylaxis. Predicting the risk of developing anaphylaxis before performing OFC is valuable information in evaluating tolerance as in diagnosis. The present study aims to evaluate the effectiveness of the tests used in clinical practice in predicting the risk of anaphylaxis during OFC in IgE-mediated food allergy. To our knowledge, this is the first study evaluating skin prick tests in the prediction of anaphylaxis. Material and Methods: In this descriptive cross-sectional study, the history, demographic, clinical and laboratory data of the patients, followed up with the diagnosis of IgE-mediated food allergy, on whom OFC was performed, were evaluated retrospectively. Results: Of the 254 patients who underwent OFC, 133 were followed up with a diagnosis of IgE-mediated food allergy. The mean age was 21 months (12-120), and anaphylaxis occurred in nine (6.7%) of them during OFC. According to the frequency, the food responsible for IgE-mediated food allergy was determined as milk, egg and egg-milk combination. Age during the challenge and total IgE levels were higher in the group that experienced OFC-related anaphylaxis. The tests that could best determine the risk of anaphylaxis before the challenge was the skin prick test (SPT) and prick to prick (PTP) test for milk. Milk SPT and PTP test at the time of initial diagnosis and determination of milk sIgE and egg white sIgE before challenge were found to predict the risk of anaphylaxis. The negative predictive value was over 95% in tests that gave significant results for milk. There was no statistically significant finding associated with other allergenic foods. Conclusion: In evaluating tolerance development, performing sIgE, SPT and/or PTP tests for milk before OFC is useful in predicting anaphylaxis. Studies with larger numbers of cases are needed to assess the risk of anaphylaxis caused by other foods.