Epidemiological survey of pediatric food allergy in Mashhad in Northeast Iran.

INTRODUCTION: Food allergy is an increasing problem worldwide, but the foods responsible for food allergy are not the same in different countries, probably because of the role of genetic, cultural, and nutritional factors. The aim of this study was to determine the common food allergens in pediatric patients with different presentation of food allergy.

METHODS: In this cross-sectional study, all of the patients were referred to pediatric allergy clinics affiliated with Mashhad University of Medical Sciences from September 2012 to August 2014. For patients with IgE-mediated food allergy that was diagnosed with clinical manifestations, the skin prick test was done. The results were analyzed by SPSS version 17 and statistical analysis was done with the chi-squared test and the t-test. P values < 0.05 were considered statistically significant.

RESULTS: Three hundred seventy-one patients (53.9% male, 46.1% female) with ages in the range of three months to 18 years were studied. The most frequent food allergen in all patients with decreasing prevalence were egg white (17.8%), pepper (15.8%), curry (14.3%), egg yolk (14%), cow's milk (10%), and tomato (7.8%). The most common presenting symptoms were respiratory (allergic rhinitis 45%, asthma 32%), dermatologic (atopic dermatitis 30%, urticaria 8.3%), colitis (17.5%), and gasteroesophagial reflux disease (GERD) (2%). According to the prevalence of food allergens in different age groups, we realized that, after the age of three years, the frequency of sensitization to egg white, egg yolk, cow's milk, wheat and cereals was decreased and allergy to pepper and curry was increased.

CONCLUSION: The prevalence of culprit foods that produce food allergies depends on several factors, including age, presenting manifestation, and where the patient lives. As many food allergies are outgrown, patients should be reevaluated regularly to determine whether they have lost their reactivity or not.