Helicobacter pylori and gastric or duodenal ulcer.

In patients with gastric or duodenal ulcer associated with Helicobacter pylori, treatment of the infection improves healing and prevents complications and recurrences. The drug regimen generally consists of a high-dose proton-pump inhibitor (PPI) such as omeprazole plus antibiotics. Using the standard Prescrire methodology, we conducted a review of the literature in order to determine the standard empirical antibiotic regimen for H. pylori infection in adults with gastric or duodenal ulcer in France. In 2015, due to an increase in H. pylori resistance to clarithromycin, a 7-day course of the PPI + clarithromycin + amoxicillin combination is effective in only about 70% of cases. A Cochrane systematic review and meta-analysis of trials involving thousands of patients suggests that prolonging treatment with a PPI + amoxicillin + clarithromycin or a PPI + amoxicillin + metronidazole to 10 or 14 days improves the rate of H. pylori eradication by 5% to 10%. A metanalysis of seven trials including a total of about 1000 patients showed that combination therapy with a PPI + amoxicillin + clarithromycin + metronidazole for 5 days eradicates H. pylori in about 90% of cases, compared to about 80% of cases with a PPI + amoxicillin + clarithromycin given for 7 days. Sequential treatment with amoxicillin for 5 days, followed by clarithromycin + metronidazole for 5 days, has also been tested in thousands of patients. Efficacy and adverse effects were similar to those observed when the same antibiotics were taken simultaneously for 5 days. In randomised trials, replacing clarithromycin or amoxicillin with a fluoroquinolone yielded conflicting results. In 2009, nearly 20% of H. pylori isolates were resistant to levofloxacin in France. Tetracycline has only been evaluated in combination with bismuth. The few available data on doxycycline suggest that its efficacy is similar to that of tetracycline. A fixed-dose combination of bismuth subcitrate potassium + metronidazole + tetracycline is authorised in the European Union for use in combination with omeprazole for 10 days. It seems effective, even in case of clarithromycin resistance. However, bismuth can cause encephalopathy, and its value when added to antibiotics and a PPI is poorly documented. We found no robust comparative data on second-line empirical treatments. In patients with gastric or duodenal ulcer associated with H. pylori, eradication of the bacterium reduces the risk of complications and recurrence. In mid-2015, the choice of antibiotics is based on trials in which the primary endpoint was a negative urea breath test, which is an acceptable surrogate criterion. In previously untreated patients, the first-choice empirical treatment consists of three antibiotics: amoxicillin (2 g daily), clarithromycin (1 g daily) and metronidazole (1 g daily), plus a PPI (in practice, omeprazole 40 mg daily), with each drug taken in two divided doses per day. The antibiotics may be taken either simultaneously for five days, or sequentially (amoxicillin for 5 days, followed by clarithromycin + metronidazole for 5 days). The adverse effects of these antibiotic combinations correspond to those of their component drugs, which mainly consist of gastrointestinal disorders and the disulfiram-like reaction of metronidazole. Amoxicillin can be replaced by a fluoroquinolone in patients allergic to beta-lactam antibiotics, but there is a higher risk of resistance. Tetracycline and doxycycline appear effective, as few H. pylori strains are resistant in vitro. Bismuth can cause encephalopathy and should only be used in special cases.