Hen’s egg white hypersensitivity among a group of Egyptian atopic children

Background: Egg allergy is potentially life-threatening. The prevalenceof egg allergy in Egypt is still unclear. This study is to evaluate thefrequency of egg hypersensitivity in a group of Egyptian atopic children.Methods: Eighty allergic children were enrolled, each is subjected toclinical evaluation, skin prick testing (SPT) using a commercial eggwhite extract, and serum egg white specific IgE (SpIgE) estimation. Sixpatients with suspected egg allergy consent to perform open oral eggchallenge. Results: Twenty-eight patients had history of exacerbation oftheir allergic diseases upon exposure to egg white, of these patients, 8had negative SPT and serum egg white SpIgE. SPT was positive in 25(31.2%) patients, of these patients, 3 (4%) were +3, 22 (28%) were +2,of whom 5 patients tolerate eggs without adverse effects. Serum eggwhite SpIgE was positive in 19 (24%) patients with a mean of 0.81 IU/ml(range: 0.35-4.52 IU/ML). Egg white allergy based on positive history,positive SPT and/or egg white SpIgE was detected in 23 (28.8%)patients. Open oral egg challenge was positive in one patient withpositive history but negative tests giving an overall frequency of eggallergy of 30 % (n=24).While egg white SpIgE did not correlate with theages, positive SPT was significantly more frequent among youngerpatients (t= 1.7, p=0.02). Egg sensitization and allergy did not affect theseverity of asthma (p > 0.05). Conclusion: Although positive SPT/ serumspecific IgE to eggs are good tools for diagnosis, oral food challengeremains the gold standard in suspected cases. Further wide-scale studiesare needed to outline the real prevalence of egg allergy in Egypt.Keywords: Egg allergy; children; skin prick test