Rate of food introduction after a negative oral food challenge in the pediatric population.

Oral food challenge (OFC) remains the gold standard for the diagnosis of food allergy. Children with previously diagnosed food allergy who then test negative by OFC are advised to incorporate the tested food into their diet on a regular basis to maintain the tolerance. Failure to incorporate the challenge food into their diet regularly has been linked to recurrence of food allergy. Based on previous studies, approximately 25%-30% of previously allergic patients continue a food avoidance diet despite a negative challenge. There are several factors that influence this rate of avoidance, most commonly food refusal, food-related symptoms, and fears of persistence of allergies. We sought to assess the rate of food introduction after a negative OFC in our pediatric allergy population using an anonymous questionnaire. Data collected included challenged food type, result of the OFC, the frequency of food introduction, and reasons for failure to incorporate the challenged food into the diet on a regular basis. Descriptive statistics were used to analyze the data. The study was deemed exempt from Mount Sinai IRB approval because no identifying information was collected as part of the survey. Two hundred and forty-eight questionnaires were distributed to parents with children at their appointments in the pediatric allergy practice from August 2015 to February 2016. Eighty-five questionnaires were returned (response rate of 34.3%). Of these, 50 respondents reported their children having had 109 OFCs. The remaining respondents indicated that their children had never undergone OFCs. The median age of the child was 8 years (2-20 years). Thirty-eight were male (76%), and 27 children underwent more than one OFC (54%). The foods challenged included 37 (34%) for tree nuts, 13 (12%) for peanut, 11 (10%) for seeds, 9 (8%) for baked milk and/or egg, 7 (6.4%) for soy, 7 (6.4%) for egg, 4 (3.6%) for milk, 3 (2.8%) for wheat, 3 (2.8%) for fish, 3 (2.8%) for shellfish, and 12 (11%) for other foods (chickpea, kiwi, avocado, beet, pork, and potato). Of these 109 OFCs, 82 (75.2%) were deemed to be negative. Of the 82 negative OFCs, 33 (40%) were tree nuts, 8 (10%) were peanuts, 8 (10%) were seeds, 6 (7%) were baked milk and/or egg, 6 (7%) were egg, 4 (4.5%) were soy, 2 (2%) were fish, 2 (2%) were shellfish, 1 was milk, 1 was wheat, and 11 (13.5%) were other foods (as mentioned above). After these 82 negative OFCs, 73 (89%) foods were added into the diet to some degree and 6 (7.3%) foods continued to be avoided in the diet. Three responders did not answer whether the challenged food was incorporated into the diet. For the foods that were added into the diet after a negative OFC, 45 (62%) were consumed daily or weekly, whereas 28 (38%) were consumed monthly or a few times a year. Reasons for not incorporating the challenge food in the diet regularly were solicited with multiple choice options and an open-ended question. Majority of responders indicated reasons for not consuming the food regularly, including the child disliking the food (11), fear of a reaction (9), and the food not being a routine part of the family’s diet (5). One respondent indicated that the “child [was] indifferent” to the challenged food. Interestingly, it was noted that peanuts and tree nuts comprised 60% of the foods that were never introduced or included in the diet only a few times a year. Five children did not incorporate 6 challenged foods into their diet after a negative OFC. These foods included tree nuts, peanut, and chickpea. The age of these children ranged from 8 to 12.5 years (median 12 years). Three of these children had multiple food allergies. In summary, the findings from our pediatric population show that after a negative food challenge, approximately 20% of the children were either still avoiding the food completely or seldom included the challenged food into their diet. This is comparable to previous reports of reintroduction failures after negative food challenges. Peanut and tree nuts accounted for the majority (60%) of foods that were not incorporated into the diet regularly after a negative food challenge. These results indicate that barriers to the reintroduction of challenged foods still exist, particularly for nuts. Families may continue to need guidance and support during the reintroduction process. Limitations of this study include its small sample size from a single institution, limiting the generalizability of this data. Responders were not asked whether the child had past reactions to these challenged foods, the severity of the reactions, or whether the suspicion of allergy was due to other factors such as prior positive test results. The time lapse between the OFC and this questionnaire was not recorded. Furthermore, the questionnaire inquired only about the frequency of consumption; responders were not asked to quantify the amount of food allergen consumed. Despite these limitations, these results show that providers should be aware that patients do not necessarily incorporate the foods into the diet after negative challenges. In light of new evidence indicating that early introduction of peanut with regular consumption can help decrease rates of peanut allergy and guidance documents for providers to encourage this process, these results show that providers should be aware that postchallenge counseling and dietary guidance are necessary to address any potential barriers to food introduction after negative OFCs. They should provide explicit guidance on how to incorporate the challenged foods into the diet and emphasize the importance of doing so. Follow-up contacts can be made with the families to assess barriers and address concerns, if any. Finally, for those undergoing food challenges to document the outgrowth of confirmed food allergies, it is important that families be educated to continue to carry their emergency