immunology allergic disorders
Food Allergy
Key Points
Food allergy is commonly mediated by IgE (typically resulting in acute systemic allergic reactions) or T cells (typically resulting in chronic gastrointestinal symptoms). Distinguish food allergy from nonimmune reactions to food (eg, lactose intolerance, irritable bowel syndrome, infectious gastroenteritis) and reactions to additives (eg, monosodium glutamate, metabisulfite, tartrazine) or food contaminants. If the diagnosis is not clinically obvious in adults or if children are being evaluated, do skin tests, an allergen-specific serum IgE test, or an elimination diet. Make sure patients understand that in an elimination diet, they can eat only foods on the list and only pure foods (which excludes many commercially prepared foods). Other treatments include cromolyn, immunotherapy for desensitization and monoclonal antibodies. 