Ige-mediated food allergy - Extensive review of the literature

Adverse reactions to food, i.e. food allergy and intolerance have gained co nsiderable attention. This overview focuses on the diagnosis and management of IgE-mediated food allergy that is believed to be responsible for most i mmediate-type food-induced hypersensitivity reactions. Clinically, these re actions are characterised by a variety of signs and symptoms that occur wit hin minutes or hours after consumption of the offending food. Reactions may be limited or more generalised with involvement of the skin, nose, eyes, a nd/or lungs. In more severe cases, cardiovascular symptoms including hypote nsion, shock, cardiac dysrhythmias and death can occur. In food-allergic in dividuals, IgE is produced against naturally occurring food components, pri marily glycoproteins that usually retain their allergenicity after heating and/or proteolysis. While adults tend to be allergic to fish, crustaceans, peanuts and tree nuts, children tend to be allergic to cow's milk, egg whit e, wheat and soy more frequently. "Emerging" food allergens include tropica l fruits, sesame seeds, psyllium, spices and condiments. These allergies fr equently represent a cross-allergy to an allergen derived from another sour ce, e.g. pollens or natural rubber latex. The evaluation of IgE-mediated fo od allergy relies on a careful history, physical examination, appropriate s kin testing or in vitro testing with food extracts, and/or double blind, pl acebo-controlled food challenges. Avoidance remains the mainstay of therapy . However, allergens may be "hidden" and labelling can be non-precise or mi sleading, thereby severely hampering prevention. Patients with severe aller gies should keep at hand an emergency kit with adrenaline, an antihistamine and an injectable rapid onset-of-action corticosteroid. At present there i s no evidence to support the use of immunotherapy, except for research purp oses. Production of "hypoallergenic" food is hampered by incomplete methods for assessing the allergenic potential of such novel foods.