Helicobacter pylori in gastric biopsies--should you trust the pathology report?

The presence of Helicobacter pylori in gastric biopsies is closely associated with gastritis and duodenal ulceration. We have assessed the reliability of H pylori identification on haematoxylin and eosin (H & E) stained sections of gastric biopsies showing gastritis. A set of 20 slides was shown to 20 histopathologists (a total of 400 diagnoses); 11 of them were H pylori-positive, assessed using two special stains. Participants were asked to comment on the presence or absence of H pylori on H & E alone. The overall detection rate in positive cases was 66%. All pathologists missed at least one case, and there were 25 false-positive diagnoses overall. We conclude that identification of H pylori is unreliable in gastric biopsies if H & E alone is used. Clinicians who use the presence of H pylori as a basis for treatment should be aware of this problem.