The purpose of this study is to improve the overall management of patients with Eosinophil Esophagitis. Currently, the best way to monitor Eosinophil Esophagitis is repeating the endoscopy procedure. The investigators plan to identify a biomarker in the blood (a measurable substance) that tracks with disease activity and will reduce the need for follow-up endoscopies.

By definition, Eosinophil Esophagitis involves the presence of eosinophils in the esophageal mucosa. Although incompletely understood, the pathophysiology of Eosinophil Esophagitis is thought to include food allergen driven inflammation in the esophageal mucosa that triggers release of mediators for recruitment of eosinophils. The mediators, such as eotaxin, invoke eosinophil activation and trafficking into the esophageal tissue. The subsequent release of mediators from eosinophils and other cells, including mast cells and basophils, promotes inflammation and fibrosis resulting in Eosinophil Esophagitis symptoms. This protocol focuses on early eosinophil activation events in Eosinophil Esophagitis in the peripheral circulation, specifically activation of surface β1 integrin, as a biomarker for disease activity reflecting eosinophils destined for trafficking into the esophagus. Demonstrating a correlation between disease activity and a peripheral biomarker may ultimately facilitate a timelier, less invasive and less costly management strategy for Eosinophil Esophagitis.

Inclusion Criteria:

• Male or female with no health concerns that might affect the outcome of the study,
• Age 18 years of age and older
• Esophageal dysfunction with a predominant symptom of solid food dysphagia and/or esophageal food impaction
• Esophageal eosinophilia (>15 eosinophils/HPF) shown on biopsy
• In the opinion of the investigator, capable and willing to grant written informed consent and cooperate with study procedures and requirements.

Exclusion Criteria:

• Major health problems such as autoimmune disease, heart disease, type I and II diabetes, uncontrolled hypertension or lung diseases other than asthma. The listed health problems are definitive exclusion but decisions regarding major health problems not listed will be based upon the judgment of the investigator,
• Pregnant or lactating females or has a planned pregnancy during the course of the study.

Adult patients (>18 yr) will be recruited from the Gastroenterology clinic following a diagnostic endoscopy for esophageal dysfunction with predominant symptom(s) of solid food dysphagia and/or esophageal food impaction. Patients with esophageal biopsy showing greater than 15 EOS/hpf (pathology results typically available within three business days) despite greater than two months use of high dose proton pump inhibitor will be invited to participate and enroll in the study within 1 week of the endoscopy.