Similarities and differences among eosinophilic esophagitis, proton-pump inhibitor-responsive esophageal eosinophilia, and reflux esophagitis: comparisons of clinical, endoscopic, and histopathological findings in Japanese patients.

<bold>Background: </bold>Esophageal eosinophilia is classified as either eosinophilic esophagitis (EoE) or proton-pump inhibitor-responsive esophageal eosinophilia (PPI-REE), depending on the response to PPI treatment. The aim of this study was to compare the clinical, endoscopic, and histopathological findings of EoE and PPI-REE in Japanese patients. In addition, the characteristics of these cases were compared with those of reflux esophagitis (RE) cases.<bold>Methods: </bold>Eleven patients diagnosed with EoE, 16 with PPI-REE, and 39 with RE, who were all consecutively examined from 2005 to 2015 at Shimane University Hospital, were enrolled. Clinical, endoscopic, and histopathological esophageal findings in these groups were retrospectively examined and compared.<bold>Results: </bold>The differences in the clinical characteristics of EoE and PPI-REE were not remarkable, though patients with EoE and PPI-REE were younger, presented a higher prevalence of allergic comorbidities, and complained of symptoms of dysphagia more frequently than those with RE. The only noteworthy differences between EoE and PPI-REE were more frequent reports of asthma (36.4 vs. 2.6 %) and food allergy (27.3 vs. 0 %) by patients with EoE (P < 0.05, P < 0.05, respectively). Endoscopic findings in patients with EoE and PPI-REE were similar, with the presence of esophageal erosions in a small percentage of PPI-REE cases being the only difference. There were no histopathological differences between EoE and PPI-REE.<bold>Conclusions: </bold>Comparisons of clinical, endoscopic, and histopathological findings between EoE and PPI-REE showed that these two types have similar characteristics, though EoE patients showed a higher atopic background. Predicting PPI responsiveness in cases with esophageal eosinophilia is difficult and requires further investigation. [ABSTRACT FROM AUTHOR]