Quantitative Analysis of Tug Sign: An Endoscopic Finding of Eosinophilic Esophagitis

Eosinophilic esophagitis (EoE) is a chronic immune-mediated disorder characterized by esophageal inflammation and dysfunction, with a rising incidence affecting approximately 1:1000 individuals worldwide.^1,2 Chronic inflammation can lead to tissue remodeling in the esophagus with fibrosis in the lamina propria that is partially responsible for symptoms and complications of EoE.^3,4 At times, a firmness to the esophagus can be appreciated with a noticeable force required to obtain biopsies from EoE. This sensation has been described as the "tug" or "pull" sign.^5,6 Recently, with the advent of endoscopic functional luminal impedance, the fibroelastic properties of the esophagus, including diminished compliance and distensibility, have been described in patients with EoE.⁷ Quantification of these fibroelastic properties of the esophagus may aid in diagnosis and prognosis of EoE. To this date, a method to quantitatively measure the "tug sign" has not been developed. The primary objective of this study was to measure if a quantifiable difference in force is required to obtain endoscopic esophageal biopsies in patients with EoE compared with those without.