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Medline ® Abstracts for References 12,16

of 'Oral food challenges for diagnosis and management of food allergies'

Oral food challenges in children with a diagnosis of food allergy.
Fleischer DM, Bock SA, Spears GC, Wilson CG, Miyazawa NK, Gleason MC, Gyorkos EA, Murphy JR, Atkins D, Leung DY
J Pediatr. 2011;158(4):578.
OBJECTIVE: To assess the outcome of oral food challenges in patients placed on elimination diets based primarily on positive serum immunoglobulin E (IgE) immunoassay results.
STUDY DESIGN: This is a retrospective chart review of 125 children aged 1-19 years (median age, 4 years) evaluated between January 2007 and August 2008 for IgE-mediated food allergy at National Jewish Health and who underwent an oral food challenge. Clinical history, prick skin test results, and serum allergen-specific IgE test results were obtained.
RESULTS: The data were summarized for food avoidance and oral food challenge results. Depending on the reason for avoidance, 84%-93% of the foods being avoided were returned to the diet after an oral food challenge, indicating that the vast majority of foods that had been restricted could be tolerated at discharge.
CONCLUSIONS: In the absence of anaphylaxis, the primary reliance on serum food-specific IgE testing to determine the need for a food elimination diet is not sufficient, especially in children with atopic dermatitis. In those circumstances, oral food challenges may be indicated to confirm food allergy status.
Department of Pediatrics, National Jewish Health, Denver, CO 80206, USA.
Microarray immunoassay: association of clinical history, in vitro IgE function, and heterogeneity of allergenic peanut epitopes.
Shreffler WG, Beyer K, Chu TH, Burks AW, Sampson HA
J Allergy Clin Immunol. 2004;113(4):776.
BACKGROUND: IgE epitope mapping of food allergens is a prerequisite for engineering hypoallergenic immunotherapeutic agents and might reveal basic information regarding a patient's immune response. Mapping of large numbers of epitopes by using individual patient sera has been impractical with current techniques.
OBJECTIVE: We sought to develop a peptide microarray-based immunoassay to map peanut epitopes by using microliter quantities of serum.
METHODS: A set of 213 overlapping 20-residue peptides was synthesized corresponding to the primary sequences of Ara h 1, Ara h 2, and Ara h 3. These were arrayed in triplicate along with the corresponding recombinant proteins onto glass slides and used for immunolabeling.
RESULTS: Seventy-seven patient and 15 control sera were analyzed. The majority of patients (97%) had specific IgE to at least one of the recombinant allergens, and 87% had detectable IgE to sequential epitopes. Microarray mapping correlated well with previous studies. However, the analysis of individual patients revealed remarkable heterogeneity in the number and patterns of epitope recognition. High epitope diversity was found in patients with a history of more severe allergic reactions. Also, sensitization of effector cells with more diverse IgE antibodies conferred greater reactivity to specific allergen.
CONCLUSIONS: The protein microarray immunoassay confirmed that Ara h 1, Ara h 2, and Ara h 3 are major peanut allergens and allows for parallel epitope analysis. This has led to the discovery of an additional important epitope of Ara h 1 and the recognition of a high degree of patient heterogeneity. This qualitative difference in epitope diversity might provide prognostic information about the patient.
Jaffe Food Allergy Institute, Division of Allergy and Immunology, Department of Pediatrics, Mount Sinai Medical Center, Box 1198, One Gustave L. Levy Place, New York, NY 10029, USA.