Argyrophilic nucleolar organizer regions in Helicobacter pylori -associated gastric lesions
Three hundred and fifty biopsies from patients undergoing upper gastrointestinal endoscopy were studied for histopathological changes, H. pylori infection and argyrophilic nucleolar organizer region (AgNOR) counts. Histopathological examination revealed normal gastric mucosa in 10 (2.85%), gastritis in 254 (72.56%), intestinal metaplasia in 12 (4.0%), dysplasia in 13 (3.7%) and adenocarcinoma in 61 (17.4%). The mean (SD) AgNOR count was 1.66 (0.20) in normal, 2.43 (0.64) in gastritis, 3.09 (0.52) in intestinal metaplasia, 4.17 (0.31) in dysplasia, and 6.57 (0.98) in carcinoma. A statistically significant difference was observed between the AgNOR count of normal gastric mucosa and gastritis (p<0.001), gastritis and dysplasia (p<0.001), and dysplasia and adenocarcinoma (p<0.001). A statistically significant increase in mean AgNOR count was found with increase in H. pylori density in gastric biopsies (p<0.001) with gastritis. No significant difference was observed between mean AgNOR count of intestinal and diffuse type carcinomas. The AgNOR count in gastric biopsies with adenocarcinoma and H. pylori infection was 7.03 (0.85) as compared to 6.89 (0.73) in gastric biopsies with evidence of adenocarcinoma but without H. pylori infection. The difference was not statistically significant. The findings support the role of H. pylori as a promoting agent in gastric carcinogenesis by stimulating gastric epithelial cell proliferation at the stage of chronic inflammation, thereby making the cells more susceptible to endogenous or exogenous carcinogenic agents.