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Disease Etiology
Oral allergy syndrome (OAS) is an IgE-mediated food hypersensitivity (1). It has been defined as "a complex of symptoms induced by exposure of the oral and pharyngeal mucosa to food allergens" (2). Although any reaction triggered by mucosal exposure to a food allergen, of either plant or animal origin, can be classified as OAS, the term is most closely associated with symptoms caused by allergens in plant foods that cross-react with pollens (3). Egger and others