Eosinophilic esophagitis: diagnostic tests and criteria

Abstract

Purpose of review: To present the clinical, endoscopic, and histologic features of eosinophilic esophagitis (EoE), review the current diagnostic guidelines for EoE, and present an approach for diagnosis of EoE. It will also highlight selected techniques that are under development that may be useful in the future for diagnosis of EoE.

Recent findings: Recently updated guidelines emphasize that EoE is a clinicopathologic condition. Specifically, three criteria must be met to diagnose EoE: clinical symptoms of esophageal dysfunction; an esophageal biopsy with a maximum eosinophil count of at least 15 eosinophils per high-power microscopy field, with few exceptions; and exclusion of other possible causes of esophageal eosinophilia, including proton-pump inhibitor responsive esophageal eosinophilia (PPI-REE). A PPI trial is typically required both to assess for PPI-REE and to evaluate for the presence of concomitant gastroesophageal reflux disease.

Summary: EoE is a chronic, immune-mediated disorder. Because no single symptom, endoscopic finding, or histopathologic feature is pathognomonic, diagnosis can be challenging. In the future, symptom scores, tissue or serum biomarkers, and genetic testing may play a role in diagnosis, but these methods have yet to be validated and are not yet recommended for routine clinical use.

Figure 1

Typical endoscopic findings in EoE. (A) Fixed esophageal rings, previously termed corrugation or trachealization. (B) Transient esophageal rings, previously termed felinization. (C) Linear furrows, as well as mucosal pallor, congestion, and loss of vascularity. (D) White plaques and exudates, as well as mucosal pallor, congestion, and loss of vascularity. (E) Crêpe-paper mucosa with a mucosal rent after passage of the endoscope through a narrow caliber esophagus. This occurred without endoscopic dilation.

Figure 1

Typical endoscopic findings in EoE. (A) Fixed esophageal rings, previously termed corrugation or trachealization. (B) Transient esophageal rings, previously termed felinization. (C) Linear furrows, as well as mucosal pallor, congestion, and loss of vascularity. (D) White plaques and exudates, as well as mucosal pallor, congestion, and loss of vascularity. (E) Crêpe-paper mucosa with a mucosal rent after passage of the endoscope through a narrow caliber esophagus. This occurred without endoscopic dilation.

Figure 1

Typical endoscopic findings in EoE. (A) Fixed esophageal rings, previously termed corrugation or trachealization. (B) Transient esophageal rings, previously termed felinization. (C) Linear furrows, as well as mucosal pallor, congestion, and loss of vascularity. (D) White plaques and exudates, as well as mucosal pallor, congestion, and loss of vascularity. (E) Crêpe-paper mucosa with a mucosal rent after passage of the endoscope through a narrow caliber esophagus. This occurred without endoscopic dilation.

Figure 1

Typical endoscopic findings in EoE. (A) Fixed esophageal rings, previously termed corrugation or trachealization. (B) Transient esophageal rings, previously termed felinization. (C) Linear furrows, as well as mucosal pallor, congestion, and loss of vascularity. (D) White plaques and exudates, as well as mucosal pallor, congestion, and loss of vascularity. (E) Crêpe-paper mucosa with a mucosal rent after passage of the endoscope through a narrow caliber esophagus. This occurred without endoscopic dilation.

Figure 1

Typical endoscopic findings in EoE. (A) Fixed esophageal rings, previously termed corrugation or trachealization. (B) Transient esophageal rings, previously termed felinization. (C) Linear furrows, as well as mucosal pallor, congestion, and loss of vascularity. (D) White plaques and exudates, as well as mucosal pallor, congestion, and loss of vascularity. (E) Crêpe-paper mucosa with a mucosal rent after passage of the endoscope through a narrow caliber esophagus. This occurred without endoscopic dilation.

Figure 2

Typical histologic features of EoE. In this esophageal biopsy specimen, a marked infiltrate of eosinophils is noted in the epithelium. In addition to the increased number of cells, eosinophilic microabscesses are noted (white arrow) and there is eosinophil degranulation (white asterisks). The basal layer is also substantially hypertrophied.

Figure 3

A diagnostic algorithm for EoE. First, the condition must be suspected clinically, and on endoscopy it is imperative that esophageal biopsies are obtained regardless of the endoscopic appearance of the esophagus. If the biopsies show at least 15 eos/hpf, then the diagnosis of EoE is a possibility, but it is not confirmed. The other causes of esophageal eosinophilia, in particular GERD and PPI-REE must be assessed, which is best done by treating with a high dose PPI trial for 8 weeks. The endoscopy is then repeated. If there are persistent symptoms and biopsies again show ≥ 15 eos/hpf, then the diagnosis of EoE is confirmed. If the biopsies show resolution of esophageal eosinophilia, then the patient either has PPI-REE or GERD.