Epidemiology of IgE-mediated food allergy

摘要

Despite the large number of foods that may cause immunoglobulin E (IgE)-mediated reactions, most prevalence studies have focused onthe most common allergenic foods, i.e. cow’s milk, hen’s egg, peanut, tree nut, wheat, soya, fish and shellfish.Food allergy peaks during the first two years of life, and then diminishes towards late childhood as tolerance to several foods develops.Based on meta-analyses and large population-based studies, the true prevalence of food allergy varies from 1% to >10%, depending on thegeographical area and age of the patient.The prevalence of food allergy in South Africa (SA) is currently being studied. The prevalence of IgE-mediated food allergy in SAchildren with moderate-to-severe atopic dermatitis is 40%; however, this represents a high-risk population for food allergy. Preliminary datafrom the South African Food Sensitisation and Food Allergy (SAFFA) study, which is investigating food allergy in an unselected cohort of1 - 3-year olds, show a prevalence of 11.6% sensitisation to common foods. Food allergy was most common to egg (1.4%) and peanut (1.1%).Food allergy appears to be the most common trigger of anaphylactic reactions in the community, especially in children, in whom food isresponsible for ≥85% of such reactions. In adults, shellfish and nut, and in children, peanut, tree nut, milk and egg, are the most commontriggers of food-induced anaphylaxis.