Key Points
ÎFOOD ALLERGY (FA) is an adverse health effect arising from a specific immune response that occurs reproducibly on exposure to a given food.
ÎThe symptoms of this disease can range from mild to severe and, in rare cases, can lead to anaphylaxis.
ÎThe most common food allergens are eggs, milk, peanuts, tree nuts, soy, wheat, crustacean shellfish, and fish.
ÎNonallergic food reactions, such as food intolerance, are frequently confused with FAs.
ÎFood allergy is managed by allergen avoidance or treatment of symptoms.
Definitions
ÎFOOD-INDUCED ANAPHYLAXIS is a serious, IgE-mediated allergic reaction that is rapid in onset and may cause death.
ÎGASTROINTESTINAL (GI) FOOD ALLERGIES
Note: Significant overlap may exist among these conditions. > Immediate GI hypersensitivity refers to an IgE-mediated FA in which upper GI symptoms may occur within minutes and lower GI symptoms may occur either immediately or with a delay of up to several hours. This is commonly seen as a manifestation of anaphylaxis. Among the GI conditions, acute immediate vomiting is the most common reaction and the one best documented as immunologic and IgE mediated.
> Eosinophilic esophagitis (EoE) involves localized eosinophilic inflammation of the esophagus. In children, EoE presents with feeding disorders, vomiting, reflux symptoms, and abdominal pain. In adolescents and adults, EoE most often presents with dysphagia and esophageal food impactions. In some patients, avoidance of specific foods will result in normalization of histopathology.
> Eosinophilic gastroenteritis (EG) describes a constellation of symptoms that vary depending on the portion of the GI tract involved and a pathologic infiltration of the GI tract by eosinophils, which may be localized or widespread. EoE is a common manifestation of EG.
> Food protein-induced allergic proctocolitis (AP) typically presents in infants who seem generally healthy but have visible specks or streaks of blood mixed with mucus in the stool. The lack of systemic symptoms, vomiting, diarrhea, and growth failure helps differentiate this disorder from other GI FA disorders that present with similar stool patterns.
> Food protein-induced enterocolitis syndrome (FPIES) usually occurs in young infants and manifests as chronic emesis, diarrhea, and failure to thrive. Upon re- exposure to the offending food after a period of elimination, a subacute syndrome can present with repetitive emesis and dehydration. Milk and soy protein are the most common causes.
