Inflammatory Mediators as Potential Non-Invasive Biomarkers in Subjects With Eosinophilic Esophagitis

The investigators seek to assess esophageal inflammation or lack of it in response to treatment with a novel non-invasive method that would measure eosinophil-associated inflammatory mediators in the blood and urine to determine the presence of active Eosinophilic Esophagitis. For these purposes, the investigators will correlate esophageal inflammatory mediators measured in blood and urine with histological findings identified on esophageal mucosal biopsies. Additionally, biopsies associated mediators will be assessed relative to clinical phenotype and outcome.

Inclusion Criteria: * Patient ages 1-18 undergoing upper endoscopy for suspected esophageal disease or esophageal inflammation or has histologically confirmed esophageal inflammation may be included in this study Exclusion Criteria: * Patients with a history or current diagnosis of esophageal malignancy or subjects with graft versus host disease will be excluded from the study. * Patients that are considered at high risk for biopsies at the discretion of the child's physician and/or the researcher * Patients with known bleeding disorders or patients with illnesses where bleeding would pose a threat to their health * Diagnosis other than Eosinophilic Esophagitis (EoE) i.e. Inflammatory Bowel Disease (IBD), Gastroesophageal Reflux Disease (GERD)