The Endoscopic Reference Score shows modest accuracy to predict histologic remission in adult patients with eosinophilic esophagitis

The relationship between the severity of endoscopic signs scored according to the Endoscopic Reference Score (EREFS) and histopathologic signs of eosinophilic esophagitis (EoE) has not been sufficiently explored. We aimed to determine if the EREFS system predicts histopathologic activity in EoE patients. We included 69 patients with EoE (age 35 [IQR 29-48] years; 80% male) who, between 2006 and 2014, underwent esophagogastroduodenoscopy (EGD) during which high-quality endoscopic images were taken and esophageal biopsy specimens were obtained. Per EGD, three or more depersonalized images were scored by an expert endoscopist, and histopathologic signs were scored by a pathologist with gastrointestinal expertise; both in a blinded fashion. The predictive values of endoscopic signs for disease activity (peak eosinophil count) were calculated. In addition, we measured the utility of the EREFS in the follow-up of 35 EoE patients. Individual endoscopic signs did not correspond to the peak eosinophil count or other histopathologic signs. Although the composite fibrotic signs score, inflammatory signs score, and total EREFS correlated weakly to moderately with the peak eosinophil count, none of these scores had both high positive and negative predictive values for histopathologic disease activity. In the follow-up of 35 patients, lower peak eosinophil counts were not associated with a decrease in endoscopic abnormalities. In adult patients with EoE, the EREFS system correlates with peak eosinophil counts, but their predictive value for disease activity is insufficient for clinical use. Therefore, biopsies remain indispensable for the assessment of disease activity