Risk of map‐like redness development after eradication therapy for Helicobacter pylori infection

Abstract Background Map‐like redness is a newly identified endoscopic risk factor for gastric cancer in patients who received Helicobacter pylori eradication therapy. However, the incidence rate of map‐like redness in patients who received eradication, and the risk factors for the development of map‐like redness remain unclear. We hence aimed to investigate the incidence rate of map‐like redness at 1‐year post H. pylori eradication, and evaluated its associations with map‐like redness and gastric cancer in relation with gastric condition. Materials and Methods Endoscopic severity of gastritis and map‐like redness were retrospectively evaluated according to the Kyoto Classification of Gastritis in patients who had undergone endoscopy before and after H. pylori eradication therapy. Results The incidence rate of map‐like redness for all 328 patients at a mean of 1.2 ± 0.6 years after eradication was 25.3% (95% confidence interval [CI]: 20.7%–30.4%). Patients who developed map‐like redness were older, had more severe atrophy and intestinal metaplasia, a higher total score of the Kyoto Classification of Gastritis both before and after eradication, and a higher rate of gastric cancer history than patients who did not have map‐like redness. On multivariate analysis, risk of map‐like redness was increased in patients with intestinal metaplasia (odds ratio [OR]: 2.794, 95% CI: 1.155–6.757) and taking acid inhibitors (OR: 1.948, 95% CI: 1.070–3.547). Characteristics of H. pylori ‐positive patients with gastric cancer history were patients who were older (OR: 1.033, 95% CI: 1.001–1.066), taking acid inhibitors (OR: 4.456, 95% CI: 2.340–8.484), and with occurrence of map‐like redness after eradication therapy (OR: 2.432, 95% CI: 1.264–4.679). Conclusions Map‐like redness is observed in one fourth of patients at 1‐year post eradication. Patients who developed map‐like redness were found to have severe intestinal metaplasia and taking acid inhibitors, and hence such patients require increased attention at surveillance endoscopy.