ENDOSCOPIC FINDINGS OF HELICOBACTER PYLORI INFECTION BY THE KYOTO CLASSIFICATION

Abstract

Upper gastrointestinal (GI) endoscopy, as well as upper GI series, has been recommended for gastric cancer screening, and endoscopy should continue to be the main modality for population-based screening. During endoscopic screening, gastric cancer must not be overlooked. Therefore, the whole stomach should be observed throughout and all images recorded. In addition, the background gastric mucosa should be closely observed in order to determine the risk for gastric cancer. It has been determined that Helicobacter pylori (H. pylori) infection and its associated gastric atrophy and intestinal metaplasia are closely related to the occurrence of gastric cancer; therefore, it is important to diagnose potential H. pylori infection. According to the Kyoto classification of endoscopic gastritis, the presence of non-gastritis (no infection) or active gastritis (current infection) or inactive gastritis (previous infection) can be judged according to 19 endoscopic findings. If there is no atrophy of the gastric mucosa and RAC (regular arrangement of collecting venules) can be observed in the gastric angle, H. pylori infection is unlikely. The possibility of the absence of H. pylori infection increases further if fundic gland polyps and/or red streaks are detected. In contrast, atrophy of C-2 or wider areas suggests H. pylori infection, and diffuse redness strongly suggests current infection. A map-like redness provides a very specific diagnosis of a previous infection with H. pylori. Evaluation of the background gastric mucosa will lead to subsequent effective endoscopic screening for gastric cancer.