Prevalence of adverse reactions following a passed oral food challenge and factors affecting successful re-introduction of foods. A retrospective study of a cohort of 199 children

BackgroundAfter a passed oral food challenge (OFC), regular and normal food consumption is attended. The main objective of this study is to assess the safety of tested food dietary re-introduction after a passed OFC.Patients and methodsIn 2014, a telephone survey was submitted to patients who passed OFC and those who failed it only presenting with contact urticaria (we consider these OFC as passed), between 2009 and 2013. Questionnaire items included demographic data, food allergy details, food consumption after the OFC was performed, recurring symptoms and life style changes.Results249 OFC questionnaires were collected from 199 children, 228 OFC were passed, 21 were failed exclusively due to contact urticaria. The most tested food was cows’ milk. In 71% of cases target food was re-introduced in patients diet in normal amounts. We found children >2 years introduced less frequently tested food than infants. In 2% of cases adverse reactions to offending food were reported, but severe reactions never occurred.DiscussionThe majority of children of this study ate target food regularly and their family's quality of life improved. In our study, adverse reactions frequency in patients who passed OFC was very low and never serious. We highlight the importance of re-assessing proper food consumption in every patient who passed OFC.