Clinical and endoscopic characteristics do not reliably differentiate PPI-responsive esophageal eosinophilia and eosinophilic esophagitis in patients undergoing upper endoscopy: a prospective cohort study.

OBJECTIVES: Proton-pump inhibitor-responsive esophageal eosinophilia (PPI-REE) is a newly recognized entity that must be differentiated from eosinophilic esophagitis (EoE). Little is known about this condition. We aimed to determine the prevalence of PPI-REE and EoE in patients undergoing upper endoscopy and determine features that distinguish the two groups.

METHODS: This prospective study conducted at the University of North Carolina from 2009 to 2011 enrolled consecutive adult patients undergoing outpatient upper endoscopy. Subjects had esophageal biopsies to quantify the maximum eosinophil count per high-power field (eos/hpf; hpf=0.24 mm(2)). If biopsies revealed ≥15 eos/hpf, subjects were treated with twice daily PPI for 8 weeks and endoscopy was repeated. If ≥15 eos/hpf persisted despite PPI therapy, EoE was diagnosed. If there were <15 eos/hpf, PPI-REE was diagnosed. The proportion of patients in each group was calculated, and patients with EoE and PPI-REE were compared.

RESULTS: Of the 223 subjects enrolled, 173 had dysphagia and 50 did not. Of those with dysphagia, 66 (38%) had ≥15 eos/hpf. After the PPI trial, 40 (23%) were confirmed to have EoE, and 24 (14%) had PPI-REE. Of those without dysphagia, 2 (4%) had ≥15 eos/hpf, and after the PPI trial, 1 (2%) had EoE. Compared with EoE, PPI-REE patients were more likely to be older and male and less likely to have typical endoscopic findings of EoE. However, none of the individual factors was independently predictive of PPI-REE status on multivariable analysis. Similarly, although some endoscopic findings were differentially distributed between PPI-REE and EoE, none were significantly associated with disease status on multivariable analysis.

CONCLUSIONS: Esophageal eosinophilia is common among patients undergoing esophagogastroduodenoscopy for dysphagia. Although EoE was seen in nearly a quarter of patients with dysphagia, PPI-REE was almost as common, and accounted for over one-third of those with ≥15 eos/hpf. No clinical or endoscopic features independently distinguished PPI-REE from EoE before the PPI trial.