Allergic reactions may be IgE or non-IgE mediated or may include both types of mechanisms. Food allergies are mediated by IgE antibodies to protein-a characteristic shared with other allergens such as those present in hay fever (an acute allergic nasal condition) an wasp-sting reactions.
The immediate phase is the activation of mast cells and basophils and the release of mediators such as histamine, proteases, leukotrienes and cytokines. The IgE mediated type I reaction is involved in the pathogenesis of many cases of asthma, rhinitis, urticaria and atopic eczema as well as GI adverse reactions to food.
Non-IgE mediated reactions include contact dermatitis, food-protein-induced enteropathy and celiac disease, whereas examples of mixed type reactions are atopic dermatitis, gastroenteritis and asthma.
Allergy mostly affects the body’s interface with the environment – skin, conjunctivitis, airways and gut – but any organ can be affected when the reaction involves the microvasculature.
Mechanisms of food allergy
