[Food allergies in paediatrics: Current concepts].

The concept of allergic reaction currently includes all those where an immunological reaction depends on a reaction mediated by IgE, as well as those that involve other immune mechanisms, such as T-cell regulators. There are many different clinical situations, like the classic immediate reactions (IgE mediated) such as urticaria, angioedema, immediate vomiting, abdominal pain, both upper respiratory (aphonia or rhinitis) and lower (wheezing or dyspnoea) symptom, and cardiovascular symptoms. The reactions that involve more than one organ, such as anaphylaxis, which could be an anaphylactic shock if there is cardiovascular involvement. The clinical signs and symptoms produced by non-IgE mediated reactions are usually more insidious in how they start, such as vomiting hours after the ingestion of food in enterocolitis, diarrhoea after days or weeks from starting food, dermatitis sometime after starting food. In these cases it is more difficult to associate these clinical symptoms directly with food. In this article, we attempt to clarify some concepts such as sensitisation/allergy, allergen/allergenic source, or the relationship of different clinical situations with food allergy, in order to help the paediatrician on the one hand, to prescribe strict diets in case of a suspicion based on the cause/effect relationship with the food, and on the other hand not to introduce unnecessary diets that very often have to last an excessively long time, and could lead to nutritional deficiencies in the children.