Pathophysiology of food-induced anaphylaxis.

Food-induced anaphylaxis is a steadily increasing problem in westernized countries and now represents the leading cause of anaphylaxis in the outpatient setting, particularly in children. Much of our knowledge of the pathophysiology of food-induced anaphylaxis comes from animal studies. Food anaphylaxis in humans is thought to be entirely IgE mediated. Several features appear to be unique to these reactions; factors such as exercise can lower the "threshold" for anaphylaxis in certain susceptible individuals. Different methods of thermal processing can modify the allergenicity of food proteins. Alteration of stomach pH can allow for incomplete digestion of food proteins, leading to increased absorption of intact food allergens. Low serum platelet-activating factor acetylhydrolase may predispose to fatal food-induced anaphylaxis. With a greater understanding of the pathophysiology of food-induced anaphylaxis, novel approaches not only to identify those at risk, but to treat and ultimately prevent food-induced anaphylaxis, are on the horizon.