Esophageal eosinophilia = eosinophils in squamous epithelium of esophagus. This is always abnormal and underlying cause should be identified.

Eosinophilic esophagitis (EoE) is chronic, immune / antigen-mediated esophageal disease defined by the following clinical and pathologic criteria: 1) Symptoms of esophageal dysfunction. 2) Eosinophilic inflammation isolated to esophagus (≥15 eos/hpf on biopsy) and persists after a PPI trial. 3) Secondary causes excluded. 4) Response to treatment (dietary elimination, topical corticosteroids) supports diagnosis, but not required.

To maximize likelihood of detecting eosinophilia, 2-4 biopsies should be taken from proximal and distal esophagus.

To rule out other causes, at time of initial diagnosis biopsies should be taken from antrum and/or duodenum in patients with gastric or small bowel symptoms or abnormalities on endoscopy.

PPI-REE should be suspected if esophageal symptoms + histologic findings of eosinophilia but demonstrate symptomatic and histologic response to PPI.

To exclude PPI-REE, patients with suspected EoE should undergo 2 month trial of proton pump inhibition (20-40 mg BID) then endoscopy with biopsies.

Response to PPI (clinical, endoscopic, and/or histologic) is not specific for GERD, therefore additional evaluation for GERD (i.e., ambulatory pH testing) is recommended, as per standard practice.

Complete symptom resolution is ideal, but improvements in clinical symptoms and eosinophilic esophageal inflammation are more realistic for clinical practice.

Symptoms alone cannot be used as reliable determinant of disease activity and response to therapy (symptoms often nonspecific and difficult to quantify.

Topical steroids (i.e., swallowed fluticasone or oral budesonide suspension for 8 weeks) are first line pharmacologic therapy.

Systemic steroids (prednisone) can be used if first line topical steroids fail or more rapid symptom improvement is necessary.

For those who do not show clinical or histologic improvement after a longer course of topical steroids or higher dose of systemic steroids, dietary elimination or endoscopic dilation is indicated.

Initial treatment can be dietary elimination for adults and children. Three approaches have demonstrated symptomatic and histologic efficacy: 1) Total elimination diet of all food allergens with an elemental or amino-acid based formula. 2) Targeted elimination diet guided by allergy testing. 3) Empiric six-food elimination diet removing soy, egg, milk, wheat, nuts and seafood.

Decision to pursue specific diets should take into consideration patient needs and resources.

Response to diet withdrawing/reintroducing specific food antigens should be measured with both clinical symptoms and endoscopic biopsy.

Consultation with allergist should be considered.

Esophageal dilation may be effective if symptomatic strictures that persist despite dietary and medical therapy or if critical stricture is encountered on initial endoscopy.

Patients should be well informed of risks associated with dilation, including post-dilation chest pain (up to 75% of patients), bleeding, and perforation.

EoE is a chronic disease, and patients should be counseled about high likelihood of symptom recurrence after discontinuing treatment.

Goal of maintenance therapy = minimize symptoms + prevent EoE complications.

Maintenance therapy with topical steroids and/or dietary restriction should be considered in all patients, but in particular in patients with severe symptoms, high-grade strictures, or rapid relapse following initial therapy.