Recrudescence and reinfection with Helicobacter pylori after eradication therapy in Bangladeshi adults.

BACKGROUND & AIMS: In developing countries where Helicobacter pylori infection is widespread, posttherapeutic recurrence rates may be high. Many of the limited studies available have methodological problems and show varied recurrence rates. We determined late recrudescence rates, true reinfection, and ulcer recurrence.
METHODS: One hundred five Bangladeshi patients with H. pylori infection and duodenal ulcer disease were treated with a triple therapy. Follow-up included 13C-urea breath tests, endoscopy, and biopsy-based tests. In reinfected patients, genomic typing compared pretherapeutic and posttherapeutic strains.
RESULTS: Recrudescence, associated with nitroimidazole-based treatment, occurred in 15 of 105 patients (14%) within the first 3 months, but only 8 of 105 patients tested positive 4 weeks after therapy ended. True reinfection was diagnosed in 11 of 105 patients between 3 and 18 months after therapy. The annual reinfection rate was 13%, based on a total follow-up of 84.7 patient years. Ulcer relapse occurred in 2 of 15 (13%) recrudescence cases and in 6 of 11 (55%) reinfection cases, but also in 4 of 73 (5%) H. pylori-negative patients.
CONCLUSIONS: In Bangladesh, late recrudescence of H. pylori after eradication therapy occurs within the first 3 months. The reinfection rate is high and might influence cost-benefit analyses for determining diagnostic and therapeutic procedures.