The importance of corpus biopsies for the determination of Helicobacter pylori infection.

Background: The aim of this study was to determine whether an antral biopsy alone represents an adequate tissue sample to diagnose the presence of Helicobacter pylori on the mucosa. Furthermore, we explored the conditions associated with the presence of H. pylori in the corpus. Methods: Consecutive patients who underwent an upper gastrointestinal endoscopy at a single centre between January 1995 and May 1997 were studied. Biopsies were taken at each endoscopy to assess the presence of H. pylori: two antral and two corpus biopsies for histological examination and one antral and one corpus biopsy for the CLO test. Results: A total of 620 patients underwent an upper gastrointestinal endoscopy, 307 (50%) were H. pylori infected. In 80% of the endoscopies there was total agreement between the performed biopsy tests. The addition of corpus biopsies increases the diagnostic yield by 10% in H. pylori-positive patients. Patients with only corpus infection more often showed atrophy and intestinal metaplasia compared with patients with both antral and corpus infection, 37 vs 20%, respectively (OR 2.2, 95% CI 1.1-4.4). Conclusion: One biopsy from the antrum or corpus seems to be inadequate to diagnose the presence of H. pylori on the mucosa. Patients with an infection exclusively in the corpus more often had worse mucosa pathology.