Eosinophilic diseases of the gastrointestinal tract.

Eosinophilic gastrointestinal disorders (EGIDs) are a diverse group of disorders whose diagnosis is on the rise and are characterized by symptoms caused by infiltration by eosinophils of the different sections of the digestive tract. Although little is known of their etiology, it seems to be multifactorial. Alteration of the immunological capacity of the digestive mucosa is determined by the exposure of genetically predisposed individuals to potential airborne or food allergens. EGIDs are classified based on the location of the inflammatory response even though their symptoms, prognosis, and treatment vary considerably. Eosinophilic esophagitis is the most widely recognized entity in this family and is characterized by exclusive eosinophilic infiltration of the esophagus. Breakthroughs in understanding its etiopathogeny have been extrapolated to eosinophilic gastroenteritis, a rare disease identified many years ago commonly involving the stomach and small bowel which should be distinguished from hypereosinophilic syndrome. Eosinophilic colitis, which usually affects children, could be considered a specific non-IgE-mediated allergy to food protein. The physiopathological bases of these entities need to be established in order to define specific treatment aimed at preventing and altering their clinical evolution.