The Frequency of Eosinophilic Esophagitis in Patients With Heartburn That is Refractory to Proton Pump Inhibitors

Background: Up to 40% of patients who are treated with PPIs for symptoms that are thought to be due to GERD experience only incomplete relief of their symptoms. Those patients are deemed "PPI failures." Esophageal pH monitoring studies have shown that PPI failure rarely is due to persistent acid reflux. Recently, heartburn that is refractory to treatment with PPIs has been described in patients with eosinophilic esophagitis, a disorder of unknown etiology in which eosinophils infiltrate the squamous epithelium of the esophagus, where they cause symptoms and tissue injury. Presently, it is not clear how often eosinophilic esophagitis underlies PPI failure for patients with GERD symptoms.

Purpose: To estimate the frequency with which eosinophilic esophagitis is the cause of "PPI failure" in patients thought to have heartburn due to GERD.

Methods: Patients referred to the Division of Gastroenterology at the Dallas VA Medical Center for the evaluation of heartburn that is refractory to PPI therapy will be invited to participate in the study. Patients who provide informed consent will have a medical history taken. Women of child bearing potential will have a pregnancy test. The patients' current PPI therapy will be discontinued, and patients will be treated with lansoprazole 30 mg BID for one week. The patient will return to the clinic one week later. Patients who feel that their heartburn has not improved by more than 50% from baseline will have an endoscopic evaluation. During the endoscopic examination, biopsy specimens will be taken as follows: A. Two specimens from the proximal esophagus at 20 cm from the incisor teeth. B. Two specimens from the mid-esophagus at 28 cm from the incisor teeth. C. Two specimens from the distal esophagus, 3 cm above the squamo-columnar junction. D. Two specimens from the distal esophagus, 1 cm above the squamo-columnar junction. E. Two specimens from the second portion of the duodenum (to see if the eosinophilia is confined to the esophagus, or part of a more extensive eosinophilic gastroenteritis). A diagnosis of eosinophilic esophagitis will be made if there is at least one high-power field with >25 eosinophils, or two or more high-power fields with >15 eosinophils.

Potential Benefits: This study will provide an estimate on the frequency with which eosinophilic esophagitis is the cause of "PPI failure" in patients thought to have heartburn due to GERD. This has substantial potential importance for patient management.