Gastric metaplasia and chronic inflammation at the duodenal bulb mucosa

BACKGROUND: Chronic inflammation and gastric metaplasia are often observed in biopsy specimens from the duodenal bulb of Heliobacter pylori positive patients with duodenal ulcer disease (DU). AIMS: We set out to investigate the prevalence of these lesions and their associations with other gastric and duodenal histopathological lesions. PATIENTS: A total of 1255 consecutive patients who underwent upper gastrointestinal endoscopy were recruited into the present study. METHODS: Two biopsy specimens were obtained from each of the following sites: duodenal bulb, gastric antrum, gastric body, and distal to the superior duodenal angle. These specimens were stained with hematoxylin-eosin, alcian blue periodic acid Schiff (pH 2.5) and modified Giemsa (Heliobacter pylori infection was determined only by histology). RESULTS: The mean age of the study population was 57 years, and male:female ratio 1:1.6. Overall, 235 (19%) had gastric metaplasia and/or chronic inflammation in the duodenal bulb mucosa, and H. pylori organisms could be found in 17 (1%). In univariate analyses, gastric metaplasia and/or chronic duodenal bulb inflammation positively associated with male sex (p = 0.046), Heliobacter pylori-positive chronic gastritis (p = 0.033), villous atrophy of distal duodenal mucosa, i.e., coeliac disease (p < 0.001), duodenal ulcer (p < 0.001), and duodenal bulb deformity and scarring in endoscopy (p < 0.001), but not with age (p = 0.7) nor use of nonsteroidal anti-inflammatory drugs (p = 0.055). Multivariate analysis revealed that independent risk factors for gastric metaplasia and chronic inflammation in duodenal bulb were duodenal Heliobacter pylori infection (odds ratio 1.6, 95% confidence interval CI 1.1-2.1), and villous atrophy of the distal duodenal mucosa (odds ratio 12.7, 95% CI 4.4-36.5), while chronic atrophic gastritis was protective against them (odds ratio 0.5, 95% CI 0.3-0.8). CONCLUSIONS: In addition to Heliobacter pylori infection, duodenal bulb gastric metaplasia and chronic inflammation may result from predisposition to toxic dietary components in gluten-sensitive subjects.