395 Determining the Necessity for Separate Histologic Evaluations of Proximal and Distal Biopsies in Adult Eosinophilic Esophagitis

Abstract

INTRODUCTION: Proton Pump Inhibitors (PPIs) can induce remission in up to 1/2 of patients with EoE. Understanding clinical or pathologic features of EoE that are associated with PPI-responsiveness could inform choice of PPI for therapy, rather than diet or topical steroids. The aim of this study was to determine if evaluation of mid esophageal biopsies separately from distal esophageal biopsies could reveal information important in predicting PPI response. METHODS: We utilized a de-identified database containing information derived from our institution’s electronic medical record between 2000-2017. We queried this database for patients with an ICD9 or ICD10 code for Eosinophilic Esophagitis. A total of 1,198 patients resulted. These records were manually reviewed, and an EoE diagnosis was confirmed in 749/1198 by a pathology report showing an esophageal biopsy containing an eosinophil count with ≥ 15 eosinophils/high power field. Patients with ≥ 15 eosinophils/high power field in both mid and distal esophageal biopsies (separately reported) with ≤ 15 eosinophils/high power field in both mid and distal biopsies following PPI therapy were considered to be PPI-responsive, while those with ≥ 15 eosinophils/high power field in either biopsy after PPI therapy were considered to be not responsive to PPI. 564/749 patients were excluded due to interventions other than PPI or lack of pre-EGD or post-EGD data. RESULTS: Our study constituted 43 PPI-responsive and 142 non-responsive patients (median age 23 vs.18 years, respectively; male 67% vs 68%, respectively). Dysphagia was the most common indication for EGD (56%, refer to Table 1). Patients non-responsive to PPI demonstrated a trend towards a longer duration of symptoms prior to EoE diagnosis (24 vs. 12 months, P = 0.14). In PPI-responsive patients, pre-EGD eosinophils/high power field were significantly lower in number in the mid (21 vs. 44, Figure 1, P < 0.001) and distal (30 vs. 50, P < 0.001) esophageal biopsies. CONCLUSION: Biopsies in the mid and distal esophagus had significantly fewer eosinophils in EoE patients that respond to PPI versus those that do not. Perhaps this information can be used in conjunction with other data to predict PPI response. In the future, we plan to validate these findings in other populations and examine the differences of other EoE histologic features in mid and distal esophageal biopsies.