Frequency of food allergy in a pediatric population from Spain.

We evaluated the prevalence and characteristics of the principal foods implicated in 355 children diagnosed with IgE-mediated food allergy. Diagnosis was established on the basis of positive clinical history for the offending food, positive specific IgE by skin prick test and RAST, and open food challenge. Our results showed the principal foods involved in allergic reactions are: eggs, fish, and cow's milk. These are followed in frequency by fruits (peaches, hazelnuts and walnuts), legumes (lentils, peanuts and chick peas) and other vegetables (mainly sunflower seeds). The legumes demonstrated the highest degree of clinical cross-reactivity. Most patients with food allergy reacted to one or two foods (86.7%). Only 13.3% of patients reacted to 3 or more foods, mostly to legumes and fruits. We found that food allergy begins most frequently in the first (48.8%) and second (20.4%) years of life. Allergy to proteins of cow's milk, egg, and fish begins predominantly before the second year, demonstrating a clear relationship with the introduction of these foods into the child's diet. Allergy to foods of vegetable origin (fruits, legumes and other vegetables) begins predominantly after the second year.