title: Impact of Allergic Reactions on Food-Specific IgE Concentrations and Skin Test Results.
abstract: BACKGROUND
  Although there is concern that food allergy reactions may negatively affect the natural history of food allergy, the impact of reactions on food-specific IgE (sIgE) levels or skin prick test (SPT) wheal size is unknown.
  
  
  OBJECTIVE
  To measure the effects of allergic reactions on SPT wheal size and sIgE concentrations to milk, egg, and peanut.
  
  
  METHODS
  Participants included 512 infants with likely milk or egg allergy enrolled in a multicenter observational study. Changes in sIgE level and SPT wheal size to milk, egg, and peanut were measured before and after oral food challenge (OFC) or accidental exposure for 377 participants.
  
  
  RESULTS
  The median age of the cohort at the time of analysis was 8.5 years (67% males). There were no statistically significant changes in sIgE level or SPT wheal size after positive OFC to milk, egg, or peanut (n = 20-27 for each food). Change in sIgE level and SPT wheal size was measured after 446 and 453 accidental exposure reactions, respectively. The median change in sIgE level was a decrease of 0.33 kU(A)/L (P < .01) after milk and 0.34 kU(A)/L (P < .01) after egg reactions, but no other statistically significant changes in sIgE level or SPT wheal size were observed for milk, egg, or peanut. When we limited the analysis to only those participants who had diagnostic testing done within 6 months of an accidental exposure reaction, we found that peanut SPT wheal size increased by 1.75 mm (P < .01), but a significant increase was not noted when all participants with testing done within 12 months were considered.
  
  
  CONCLUSIONS
  The results suggest that reactions from OFCs and accidental exposure are not associated with increases in sensitization among children allergic to milk, egg, or peanut.
authors.affiliation: Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY. Electronic address: scott.sicherer@mssm.edu.
authors.forename: Scott H
authors.initials: SH
authors.lastname: Sicherer
authors.affiliation: Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Md.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Wood
authors.affiliation: Department of Pediatrics, University of North Carolina, Chapel Hill, NC.
authors.forename: Brian P
authors.initials: BP
authors.lastname: Vickery
authors.affiliation: Department of Pediatrics, University of Arkansas for Medical Sciences and Arkansas Children's Hospital, Little Rock, Ark.
authors.forename: Tamara T
authors.initials: TT
authors.lastname: Perry
authors.affiliation: Department of Pediatrics, University of Arkansas for Medical Sciences and Arkansas Children's Hospital, Little Rock, Ark.
authors.forename: Stacie M
authors.initials: SM
authors.lastname: Jones
authors.affiliation: Department of Pediatrics, National Jewish Health, Denver, Colo.
authors.forename: Donald Y M
authors.initials: DY
authors.lastname: Leung
authors.affiliation: The EMMES Corporation, Rockville, Md.
authors.forename: Beth
authors.initials: B
authors.lastname: Blackwell
authors.affiliation: The EMMES Corporation, Rockville, Md.
authors.forename: Peter
authors.initials: P
authors.lastname: Dawson
authors.affiliation: Department of Pediatrics, University of North Carolina, Chapel Hill, NC.
authors.forename: A Wesley
authors.initials: AW
authors.lastname: Burks
authors.affiliation: The EMMES Corporation, Rockville, Md.
authors.forename: Robert
authors.initials: R
authors.lastname: Lindblad
authors.affiliation: Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY.
authors.forename: Hugh A
authors.initials: HA
authors.lastname: Sampson
mesh_terms: D000284:Administration, Oral; D000485:Allergens / Q000276:immunology; D010367:Arachis / Q000276:immunology; D002648:Child; D004527:Egg Proteins / Q000276:immunology; D005260:Female; D005512:Food Hypersensitivity / Q000175:diagnosis*; D006801:Humans; D007114:Immunization; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology*; D008297:Male; D008894:Milk Proteins / Q000276:immunology; D010940:Plant Proteins / Q000276:immunology; D012882:Skin Tests
chemical_list: D000485:Allergens; D004527:Egg Proteins; D008894:Milk Proteins; D010940:Plant Proteins; D007073:Immunoglobulin E
keywords: Food allergy; IgE; Natural history; Skin prick test