Chronic gastritis and Helicobacter pylori infection in University College Hospital Ibadan, Nigeria--a study of 85 fibre optic gastric biopsies.

BACKGROUND: Fibreoptic endoscopic gastric biopsy, has revealed that chronic gastritis is not only of a complex aetiological background, but also varied topographical distribution and other clinico-pathological associations. By far, the most important aetiologic association of chronic gastritis is chronic infection by the bacillus Helicobacter pylori. This study aims to highlight some of the histopathological associations between this bacterium and chronic gastritis. METHOD: We reviewed all endoscopic gastric biopsies with a histological diagnosis of chronic gastritis, with available case records and archival tissues over an 18 year period, to determine association between the various pathological features of chronic gastritis present and the presence of H. pylori infection. RESULTS: Eighty-five cases with histological diagnosis of chronic gastritis fulfilled the inclusion criteria, and Helicobacter pylori infection was found in 22.4% of them. Most patients (83.1%) with chronic gastritis had moderate to severe grades of inflammation, and most (84.2%) of the infection involved the gastric antrum. Pangastritis was uncommon (10.5%). A greater proportion of the antral biopsies (87.5%) showed moderate to severe grades of chronic gastritis as compared with 16.7% of corporal biopsies. There was an early age of acquisition of infection, starting at the second decade of life, with a peak in the 6th decade. The frequencies of atrophic gastritis and intestinal metaplasia seen complicating chronic gastritis were 16.7% and 9.4% respectively. CONCLUSION: The study shows that Helicobacter pylori infection is associated mainly with moderate to severe chronic gastritis in Nigerians. This study confirms the antral predilection of H. pylori infection, and the finding of an antral preponderance for chronic gastritis partly explains the relatively more frequent occurrence of duodenal ulcers in Nigerians as compared to gastric ulcers. Furthermore, the finding of a low prevalence of atrophic gastritis and intestinal metaplasia, as well as the rarity of pangastritis in our patients probably explains in part, the low incidence of gastric cancer in Nigeria.