Chronic inflammatory conditions with gastrointestinal symptoms and eosinophilic infiltration of the gastrointestinal mucosa.
Eosinophilic gastroenteritis is a rare and heterogeneous condition characterized by patchy or diffuse eosinophilic infiltration of gastrointestinal (GI) tissue.
Approximately 300 EG cases reported in published literature.
Patients can present at any age and across all races, with a slightly higher incidence in males.
Higher incidence in the third to fifth decades of life.
It usually runs a chronic relapsing course.
It is classified by depth of tissue involvement: mucosal, muscular and serosal types.
While any part of the GI tract can be affected, the stomach is the organ most commonly affected, followed by the small intestine and the colon.
Isolated biliary tract involvement may occur.
Patients with EG present with a combination of chronic nonspecific GI symptoms which include abdominal pain, diarrhea, occasional nausea and vomiting, weight loss and abdominal distension.
Approximately 80% have prolonged symptoms for several years.
A high degree of clinical suspicion is often required to establish the diagnosis.
Diagnosis takes about 3–4 years to develop depending upon the age of the patient.
Rarely, EG disease may manifest itself as an acute abdomen or bowel obstruction.
The most common variety of EG is mucosal disease, which presents with features of malabsorption and protein losing enteropathy.
Failure to thrive and anemia may also be a presentation of EG.
Colonic involvement may present as
lower gastrointestinal bleeding.
Muscular EG accounts for 13–70% of cases and presents with obstruction of gastric outlet or small intestine.
Muscular EG can sometimes present as an obstruction of a cecal mass or intussusception.
Subserosal EG accounts for 13% of cases in the US.
Subserosal EG presents with ascites which is usually exudative in nature, abundant peripheral eosinophilia, and has favorable responses to corticosteroids.
Subserosal EG feature include: cholangitis, pancreatitis, eosinophilic splenitis, acute appendicitis and giant refractory duodenal ulcer.
EG is usually associated with eosinophilia and elevated serum IgE, but not in all cases.
Eosinophilic infiltration and degranulation damage to the gastrointestinal tract wall
Eosinophils are normally present in gastrointestinal mucosa, though the finding in deeper tissue is almost always pathologic.
Many patients have history of other atopic conditions like eczema, asthma,
food allergy and variable IgE response to food substances.
Eosinophil recruitment into inflammatory tissue is a complex process, regulated by a number of inflammatory cytokines.
In EG cytokines IL-3, IL-5 and granulocyte macrophage colony stimulating factor (GM-CSF) may be associated with eosinophil recruitment and activation.
Eotaxin has an integral role in regulating the homing of eosinophils into the lamina propria of stomach and small intestine.
Dagnostic criteria:
the presence of gastrointestinal symptoms,
histological demonstration of eosinophilic infiltration in one or more areas of the gastrointestinal tract or presence of high eosinophil count in ascitic fluid.
no evidence of parasitic or extraintestinal disease.
Hypereosinophilia, may be absent in up to 20% of patients.
Hypoalbuminemia and other abnormalities suggestive of malabsorption may be present.
CT scan may show nodular and irregular thickening of the folds in the distal stomach and proximal small bowel.
The endoscopic appearance in eosinophilic gastroenteritis
erythema, friable, nodular, and occasional ulcerative changes.
Loss of villi, and involvement of multiple layers, submucosal edema and fibrosis may be seen.
Eosinophilic infiltration in biopsy with >20 eosinophils per high power field.
When EG is observed in association with eosinophilic infiltration of other organ systems, the diagnosis of idiopathic hypereosinophilic syndrome should be considered.
Treatment: Corticosteroids are the mainstay of therapy with as high as a 90% response rate.
Higher incidence in the third to fifth decades of life.
It is suggested that mast cells are involved in the pathogenesis of these conditions.