IS HELICOBACTER-PYLORI INFECTION RESPONSIBLE FOR POSTENDOSCOPIC ACUTE GASTRIC-MUCOSAL LESIONS

Objective. Acute gastric mucosal lesions occasionally develop after an endoscopic examination of the upper gastrointestinal tract. The incidence in Japan is 0.02%. The cause and the exact mechanism are still unknown. We therefore tested the hypothesis' that postendoscopic acute gastric mucosal lesions are related to Helicobacter pylori infection via the endoscope. Design and methods. The hypothesis was tested by the histologic detection of H. pylori with enzyme-linked immunosorbent assays, which were compared before and after the onset of lesions. In order to elucidate the transmission route, H. pylori was tested in the sera of preceding patients, who had undergone endoscopy just before and with the same endoscope as the patients who developed acute gastric mucosal lesions. Results. H. pylori was detected in eight of the 20 specimens (40.0%) taken before the onset of lesions and in 29 of the 42 specimens (69.0%) taken after the onset of lesions. Nineteen of the 23 specimens from patients with acute gastric mucosal lesions were negative for H. pylori before the onset. After the onset, 10 (52.6%) of the 19 H. pylori-negative specimens showed immunoglobulin G seroconversion to H. pylori. These observations suggest that H. pylori infection triggers acute gastric mucosal lesions. In addition, the incidence of H. pylori-postive antibody in the sera of the preceding patients was very high (88.9%). Conclusions. Postendoscopic gastric mucosal lesions are induced by H. pylori infection via the endoscope.