Stool antigen assay to screen Helicobacter pylori infection and to assess the success of 3-day and 7-day eradication therapy in the patients with partial gastrectomy

Background. Even after partial gastrectomy, Helicobacter pylori may persist in the residual stomach but be less abundant in the bacterial load. H. pylori stool antigen is a reliable noninvasive tool to detect H. pylori infection in patients without gastrectomy. We thus test whether [1] the course of H. pylori eradication therapy could be diminished [2]; stool antigen can effectively detect H. pylori infection for the patients with gastrectomy. Methods. One hundred and eight patients who had undergone partial gastrectomy were enrolled to receive panendoscopy and provided stool samples for H. pylori stool antigen within 3 days after endoscopy. The H. pylori-infected patients were then randomized to receive either a 3- or 7-day triple therapy for H. pylori eradication. Six weeks later, to evaluate the success of H. pylori eradication, patients received a follow-up endoscopy and again provided stool samples for H. pylori stool antigen. Results. Seventy out of 108 patients, proven to have H. pylori infection, were evenly randomized into 3-day and 7-day therapy groups. The H. pylori eradication rates were similar between the 3-day and 7-day triple therapy (90.9 vs. 93.8%, p > .05). Before therapy, the H. pylori stool antigen was 93% sensitive and 100% specific to detect H. pylori. After therapy, H. pylori stool antigen remain 100% sensitive and 88.3% specific to detect the failure of eradication therapy. Conclusion. H. pylori stool antigen is a highly reliable tool to screen H. pylori infection before therapy and to assess the success of eradication therapy in partial gastrectomy patients. To eradicate H. pylori infection for patients with partial gastrectomy, the duration of triple therapy can be shortened.