A LOW-RATE OF REINFECTION FOLLOWING EFFECTIVE THERAPY AGAINST HELICOBACTER-PYLORI IN A DEVELOPING-NATION (CHINA)

Background & Aims: In developed countries, reinfection after successfu l eradication of Helicobacter pylori appears unusual. High prevalences of H. pylori in developing countries may result in high reinfection r ates. The aim of this study was to determine the rate of reinfection a nd ulcer recurrence in Chinese patients cured of H. pylori and duodena l ulcer disease. Methods: One hundred eighty-four patients with duoden al ulcer disease shown by endoscopic examination (1 month) and C-14-ur ea breath test (3 months) after termination of treatment to have clear ed their H. pylori were investigated. Patients were followed up by end oscopy (12 and 24 months) and breath test (6, 9, 12, 18, and 24 months ). H. pylori status at endoscopic examination was determined by rapid urease, histology, and culture. In reinfected patients, random amplifi cation of polymorphic DNA fingerprinting was used to compare isolates before and after therapy. Results: Four patients were reinfected with H. pylori over 24 months (3 within 6 months and 1 at 24 months; averag e annual recurrence rate, 1.08%). Fingerprinting of isolates from 3 pa tients showed 1 patient (6 months) to have identical strains and the r emainder to have nonidentical strains before and after treatment. Ulce r relapse occurred in 6 patients (4 H. pylori positive). Conclusions: Reinfection with H. pylori is rare in developing countries where treat ment is effective.