Eosinophilic esophagitis: a paradigm shift for pathology

Abstract

Background: Eosinophilic esophagitis (EoE) is an increasingly recognized disease only reported in the adult literature since 1993. Our facility has the opportunity to evaluate steroid-naive EoE patients since 1988, allowing us to describe the evolution of the histologic diagnosis of EoE.

Methods: This retrospective study analyzed 95 patient charts with initial diagnosis of congenital esophageal stenosis/EoE from 1988 to 2012. Patients had dysphagia and met endoscopic criteria consistent with current EoE histologic criteria while on chronic proton-pump inhibitor therapy. Histologic slides were obtained for only 10 patients because of limited slide availability; and the slides were reviewed by a single pathologist. EoE is defined as ≥1 biopsy specimens demonstrating >15 eosinophils/HPF.

Results: Following review of histologic analysis reports, pathologists in our 2 academic hospitals began recognizing EoE as separate disease entity starting in 2007, coincidental with first EoE guidelines. After 2007, there was a clear surge in histologic diagnosis of EoE. Slides from 10 patients from 1988 to 2012 were reviewed. Of 35 biopsy sets, 19 were previously interpreted as reflux esophagitis (RE) or acute/chronic inflammation, 3 as RE with eosinophils, 2 as normal, and 11 as EoE. Reevaluation revealed EoE in 79% specimens with RE/inflammation and 100% with RE and eosinophils; remaining specimens had confirmed original diagnosis. All 10 patients had at least one set of slides meeting current EoE histologic criteria.

Conclusions: EoE as a disease has been present for at least 2 to 3 decades. This is the first report of a clearly demarcated time point reflecting a paradigm shift in the histologic diagnosis of EoE as a distinct entity resulting from a seminal consensus report.