2021 Volume 59 Issue 1 Pages 42-48
Diffuse redness (DR) is an endoscopic feature strongly suggestive of Helicobacter pylori (H. pylori) infection. However, the assessment of this feature is dependent on the setting of the device and the subjectivity of the endoscopist, which is a major issue. We, therefore, developed a procedure for DR quantification using image analysis and assessed the usefulness of the procedure. A visual assessment of the endoscopic images of 115 patients who underwent upper gastrointestinal endoscopy and an H. pylori infection examination, was done by six endoscopists. The kappa value and diagnostic accuracy of H. pylori infection according to the visual assessment using all images (0.43 and 67.7%, respectively) were higher than those using only 2 images (antrum and greater curvature of body) (0.31 and 55.8%, respectively). The kappa values using the DR quantification (0.93), when the cut-off value calculated by the receiver operating characteristic curve analysis was defined as 0.975, were much higher than those by a visual assessment using either 2 or all endoscopic images (0.31 or 0.43, respectively).
The diagnostic accuracy of DR quantification to assess H. pylori infection was 64.1%, which was equivalent to that achieved by a visual assessment using all endoscopic images. The procedure of DR quantification is expected to be used to screen current H. pylori infection because of the high interobserver agreement and diagnostic accuracy.
