Helicobacter pylori Recurrence after First- and Second-Line Eradication Therapy in Korea: The Problem of Recrudescence or Reinfection

Background Recurrence of Helicobacter pylori (H.pylori) infection is the result of either recrudescence or reinfection. Annual recurrence rates per patient-year of follow-up have been reported to vary across countries. The aim of this study was to analyze recurrence rates of H.pylori after first-line and second-line eradication therapies in Korea. Materials and Methods From 2007 to 2010, 2691 patients with H.pylori infection received first-line therapy and 573 patients who failed to respond to first-line therapy received second-line therapy. H.pylori infection and the success of eradication were assessed by endoscopic biopsy and rapid urease test or 13C-urea breath test. All patients were advised to undergo 13C-urea breath test or esophagogastroduodenoscopy with biopsy or rapid urease test 6months after eradication, with annual follow-up thereafter. Results The eradication rate of the first-line therapy was 79.9% (1283/1605) and that of the second-line therapy was 90.4% (394/436) by per protocol analysis. Annual recurrence rates sharply declined after 2-year follow-up. Annual recurrence rates within and after 2-year follow-up were 9.3 and 2.0% after first-line therapy and those of second-line therapy were 4.5 and 2.9%, respectively. Conclusions Annual recurrence rates of H.pylori showed a sharp decline after 2-year follow-up after eradication in Korean adults, which is not higher than that of Western countries. Enough time interval after treatment (i.e., 2years) is necessary to confirm eradication, and it would not be easy to distinguish between recurrence and recrudescence before 2years without identifying H.pylori strains.