Map‐Like Redness Development After Eradication Therapy for Helicobacter pylori Infection: Prospective Multicenter Observational Study

ABSTRACT Background Map‐like redness, pathological intestinal metaplasia, is observed in one‐fourth to one‐third of patients 1 year after Helicobacter pylori eradication therapy, mainly in the corpus, and is a newly identified endoscopic risk factor for gastric cancer development after eradication. However, it is unclear whether intestinal metaplasia is present before eradication at the site where the map‐like redness appears. We aimed to identify endoscopic findings that predict the occurrence of map‐like redness before H. pylori eradication. Materials and Methods As a prospective multicenter trial, the characteristics of patients in whom map‐like redness developed after eradication, and the association between the endoscopic severity of gastritis and the development of map‐like redness in patients who underwent endoscopy before and 1‐year after eradication were investigated. Results The rate of map‐like redness in all 93 patients 1‐year postsuccessful eradication was 30.1% (95% confidence interval [CI]: 21.0–40.5). All patients with map‐like redness were endoscopically observed to have intestinal metaplasia before eradication, in the site that subsequently developed map‐like redness. Patients who developed map‐like redness were older, had more severe intestinal metaplasia and nodularity and a higher total score on the Kyoto Classification of Gastritis both before and after eradication than patients who did not. On multivariate analysis, map‐like redness was found to be associated with posttreatment intestinal metaplasia (odds ratio: 8.144; 95% CI: 2.811–23.592). Conclusions In all patients who developed map‐like redness after eradication, endoscopic intestinal metaplasia was observed at the site developed map‐like redness before eradication therapy. Map‐like redness was especially observed in patients with more severe intestinal metaplasia at 1‐year after eradication. Such patients require increased attention at surveillance endoscopy, owing to generally having a higher risk of gastric cancer development. Trial Registration University Hospital Medical Information Network : UMIN000044707