Severity of endoscopically identified esophageal rings correlates with reduced esophageal distensibility in eosinophilic esophagitis

Abstract

Background/aims: A grading system for the endoscopic features of eosinophilic esophagitis (EoE) has recently been validated. The EoE Endoscopic Reference Score (EREFS) incorporates both inflammatory and remodeling features of EoE. High resolution impedance planimetry using the functional luminal imaging probe (FLIP) is a technique for quantification of esophageal remodeling. The aim of this study was to evaluate the association between endoscopic severity with EREFS and esophageal distensibility as measured with the FLIP.

Methods: Upper gastrointestinal endoscopy with biopsies and FLIP were performed in 72 adults with EoE. Endoscopic features of edema, rings, exudates, furrows, and stricture were evaluated using the EREFS system. Esophageal distensibility metrics obtained by FLIP, including the distensibility slope and distensibility plateau, were compared with EREFS parameters. Bivariate associations between EREFS parameters and histologic eosinophil density were assessed.

Results: Higher ring scores were associated with a lower distensibility plateau (rs = -0.46; P < 0.0001). An association was found between severity of exudates and eosinophil density (rs = 0.27; P = 0.02), as well as between furrows and eosinophil density (rs = 0.49; P < 0.0001). Severity of exudates and furrows, and degree of eosinophilia were not associated with the distensibility parameters.

Conclusions: Endoscopic assessment of ring severity can serve as a marker for esophageal remodeling and may be useful for food impaction risk stratification in EoE. Eosinophil count was not significantly associated with esophageal distensibility, consistent with previous reports of dissociation between inflammatory activity and fibrostenosis in EoE. Endoscopic inflammatory features show a weak correlation with histopathology but should not replace histologic indices of inflammation.

Fig. 1

Figure modified from Pandolfino et al. [17]. Distensibility was plotted as a function of the narrowest cross-sectional area versus intrabag pressure. The distensibility metrics – distensibility slope (DS) and distensibility plateau (DP) – were derived from this curve.

Fig. 2

Example endoscopic appearance and representative functional luminal imaging probe (FLIP) images during volume distension for each severity of ring score. Luminal narrowing is evident on the FLIP images with moderate to severe rings, and the distensibility plateau (DP) is decreased in severe rings.

Fig. 3

Distensibility curves (mean narrowest cross-sectional area [CSA] at various levels of intrabag pressure) compiled using summary statistics of pooled patient data for each ring severity score. The distensibility curves for ring scores of 2 and 3 showed decreased slopes and lower plateaus than those for ring scores of 0 and 1.

Fig. 4

Locally-weighted regression curve (LOESS) fitted to the scatterplot of distensibility plateau versus ring scores. A decrease in distensibility plateau is evident with increasing ring severity score.

Fig. 5

Histogram showing the percentage of patients with a history of food impaction for each ring score. Ring severity was associated with a significant difference in food impaction history (P = 0.002).