Helicobacter pylori duodenal colonization is a strong risk factor for the development of duodenal ulcer

Summary Aim : To test the hypothesis that duodenal colonization represents the final crucial step in the development of Helicobacter pylori related duodenal ulcer. Methods : Patients with non‐ulcer dyspepsia who had gastric colonization by H. pylori were included in the study. At baseline endoscopy, we evaluated the prevalence of duodenal colonization (culture, urease testing and histology), and cytotoxin‐associated gene A status (polymerase chain reaction). No patients received eradication during 1 year follow‐up. At this time, endoscopy was repeated and the incidence of duodenal ulcer was assessed. Results : Among 181 patients completing follow‐up, 53 (29%) had duodenal colonization: 72% of them were cytotoxin‐associated gene A positive, versus 37% patients without duodenal colonization (P