Histological changes in the gastric mucosa after Helicobacter pylori eradication

Background and aim: Correa described a stepwise model of changes in the gastric mucosa after Helicobacter pylori infection, from the normal gastric epithelium to chronic gastritis, atrophy, intestinal metaplasia, dysplasia and adenocarcinoma. The aim of this study is to assess the reversibility of these mucosal changes after H. pylori eradication. Methods: The study sample consisted of 89 patients who underwent at least two gastric biopsies from 1990 to 2000, with a positive finding for H. pylori in the first and a negative finding in the second. Specimens were evaluated for acute and chronic inflammation, lymphoid aggregates, proliferation, mucosal atrophy, intestinal metaplasia, dysplasia, and MUC5AC and MUC6 expression using histochemical and immunohistochemical methods. Results: The average time between biopsies was 23.15 ± 26.30 months. There was a significant decrease in acute and chronic inflammation scores, from 1.48 ± 1.10 to 0.23 ± 0.63 and from 2.67 ± 0.68 to 1.44 ± 1.04, respectively (P < 0.001), and in a number of lymphoid follicles, from 42.68% to 21.95% of cases (P < 0.008). The number of glands increased from 39.08 ± 16.67/mm² to 48.86 ± 17.93/mm² after eradication (P = 0.062). Intestinal metaplasia was found in 17.07% of the cases, with no change over time. Dysplasia appeared in one case 2 years after eradication. In 27 patients, the Ki67 labeling index decreased significantly after eradication, while MUC5AC and MUC6 expression increased. Conclusion: Our findings, although not conclusive for arrest of the malignant potential, support the importance of H. pylori eradication in the prevention of gastric cancer.