Clinical manifestations of immunoglobulin E-mediated food allergy, including pollen-food allergy syndrome.

Immunoglobulin E-(IgE) mediated food allergy affects people of all ages but does not have a consistent presentation and may result in various manifestations, even for an individual. The onset of symptoms is usually quite rapid, minutes to a few hours after consumption of the allergen, although exceptions exist. Cutaneous and gastrointestinal symptoms are the most common clinical manifestations; however, they are not present in all allergic reactions. Clinicians, particularly those in emergency care settings, need to be aware that the lack of cutaneous manifestations does not exclude the possibility of anaphylaxis. It is extremely unusual for food allergy reactions to present with isolated upper or lower respiratory symptoms, nor is chronic urticaria a manifestation of food allergy. Clinical manifestations of IgE-mediated food allergy range from mild to severe and, in rare cases, can be fatal. Mild, localized reactions, such as those that occur in pollen-food allergy syndrome, occur in individuals with sensitization to pollens. A small proportion of patients with this syndrome develop anaphylaxis. Alcohol, medications (nonsteroidal anti-inflammatory drugs, antacids), physical exertion, increased body temperature, acute infection, and menstruation are factors that are known to augment the severity of food-induced allergic reactions.