title: Food Challenge and Community-Reported Reaction Profiles in Food-Allergic Children Aged 1 and 4 Years: A Population-Based Study.
abstract: BACKGROUND
  Oral food challenge is the main tool for diagnosing food allergy, but there is little data on the reaction profiles of young children undergoing challenges, nor how these reactions compare to reactions on accidental ingestion in the community.
  
  
  OBJECTIVE
  To compare reaction profiles from food challenges and parent-reported reactions on accidental ingestion, and assess predictors of severe reactions.
  
  
  METHODS
  HealthNuts is a longitudinal population-based cohort study of 5276 1-year-old infants. Infants underwent skin prick tests and those with identifiable wheals were offered food challenges. Food challenges were repeated at age 4 years in those with previous food allergy or reporting new food allergies. Community-reported reactions were ascertained from parent questionnaires.
  
  
  RESULTS
  Food challenges were undertaken in 916 children at age 1 year and 357 children at age 4 years (a total of 2047 peanut, egg, or sesame challenges). Urticaria was the most common sign in positive challenges at both ages (age 1 year, 88.7%, and age 4 years, 71.2%) although angioedema was significantly more common at age 4 years (40.1%) than at age 1 year (12.9%). Anaphylaxis was equally uncommon at both ages (2.1% and 2.8% of positive challenges at ages 1 and 4 years, respectively) but more common for peanut than for egg (4.5% and 1.2% of positive challenges at ages 1 and 4 years, respectively). The patterns of presenting signs reported during community reactions were similar to those observed in formal food challenges. Serum food-specific IgE levels of 15 kU/L or more were associated with moderate to severe reactions but skin prick test was not.
  
  
  CONCLUSIONS
  There was a shift from the most common presenting reaction of urticaria during food challenges toward more angioedema in older children. Serum food-specific IgE levels were associated with reaction severity.
authors.affiliation: Murdoch Childrens Research Institute, Parkville, Victoria, Australia; Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong.
authors.forename: Joshua C K
authors.initials: JCK
authors.lastname: Chan
authors.affiliation: Murdoch Childrens Research Institute, Parkville, Victoria, Australia.
authors.forename: Rachel L
authors.initials: RL
authors.lastname: Peters
authors.affiliation: Murdoch Childrens Research Institute, Parkville, Victoria, Australia; School of Population and Global Health, University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Jennifer J
authors.initials: JJ
authors.lastname: Koplin
authors.affiliation: School of Population and Global Health, University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Shyamali C
authors.initials: SC
authors.lastname: Dharmage
authors.affiliation: School of Population and Global Health, University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Lyle C
authors.initials: LC
authors.lastname: Gurrin
authors.affiliation: Murdoch Childrens Research Institute, Parkville, Victoria, Australia; Department of Paediatrics, University of Melbourne, Parkville, Victoria, Australia; Department of Paediatrics and the Liggins Institute, The University of Auckland, Auckland, New Zealand.
authors.forename: Melissa
authors.initials: M
authors.lastname: Wake
authors.affiliation: Murdoch Childrens Research Institute, Parkville, Victoria, Australia; Department of Paediatrics, University of Melbourne, Parkville, Victoria, Australia; Department of Allergy and Immunology, Royal Children's Hospital, Parkville, Victoria, Australia.
authors.forename: Mimi L K
authors.initials: MLK
authors.lastname: Tang
authors.affiliation: Telethon Kids Institute, School of Paediatrics and Child Health, University of Western Australia, Perth, Western Australia, Australia.
authors.forename: Susan
authors.initials: S
authors.lastname: Prescott
authors.affiliation: Murdoch Childrens Research Institute, Parkville, Victoria, Australia; Department of Paediatrics, University of Melbourne, Parkville, Victoria, Australia; Department of Allergy and Immunology, Royal Children's Hospital, Parkville, Victoria, Australia; Institute of Inflammation and Repair, University of Manchester, Manchester, United Kingdom. Electronic address: katie.allen@rch.org.au.
authors.forename: Katrina J
authors.initials: KJ
authors.lastname: Allen
mesh_terms: D000284:Administration, Oral; D000485:Allergens / Q000276:immunology; D000707:Anaphylaxis / Q000209:etiology / Q000517:prevention & control*; D010367:Arachis / Q000276:immunology; D002675:Child, Preschool; D015331:Cohort Studies; D021181:Egg Hypersensitivity / Q000150:complications / Q000175:diagnosis*; D004531:Eggs / Q000009:adverse effects; D005260:Female; D006801:Humans; D007114:Immunization / Q000009:adverse effects / Q000379:methods; D007073:Immunoglobulin E / Q000097:blood; D007223:Infant; D008297:Male; D021183:Peanut Hypersensitivity / Q000150:complications / Q000175:diagnosis*; D031685:Sesamum / Q000276:immunology*; D011795:Surveys and Questionnaires
chemical_list: D000485:Allergens; D007073:Immunoglobulin E
keywords: Anaphylaxis; Angioedema; Community reactions; Egg allergy; Food allergy; Oral food challenge; Peanut allergy; Reaction profiles; Sesame allergy; Skin prick test; Specific IgE; Urticaria