Treatment regimens for Helicobacter pylori infection in children: is in vitro susceptibility testing helpful?

Background: Treatment regimens for Helicobacter pylori have variable success rates, and data comparing effectiveness with respect to strain sensitivity are relatively scarce. Objective: To evaluate the efficacy of two treatment regimens for eradication of H. pylori and the impact of bacterial susceptibility testing. Study Design: 265 children endoscopically diagnosed with H. pylori infection were randomly assigned to receive omeprazole + amoxicillin with clarithromycin or omeprazole + amoxicillin with metronidazole. Bacterial culture and susceptibility was performed in a subgroup. Eradication was assessed by 13C-urea breath test. Results: Eradication was achieved in 73.4% by omeprazole + amoxicillin with metronidazole and in 62.6% by omeprazole + amoxicillin with clarithromycin (P = 0.078). H. pylori was cultured successfully in 105 patients. Resistance to metronidazole was detected in 31.4% of the isolates and resistance to clarithromycin in 15%. Eradication rate by omeprazole + amoxicillin with metronidazole for metronidazole-susceptible bacteria (N = 38) was 90%, and for resistant bacteria (N = 19) it was 42%. Only 75% of clarithromycin-sensitive strains were successfully treated by omeprazole + amoxicillin with clarithromycin, and none of the cases with clarithromycin-resistant strains responded to omeprazole + amoxicillin with clarithromycin treatment. Conclusion: There is a trend of greater efficacy of eradication with omeprazole + amoxicillin with metronidazole versus omeprazole + amoxicillin with clarithromycin therapy. Although resistance negatively influences eradication, first-line sensitivity-based treatment would be expected to improve this rate only slightly. Susceptibility testing should probably be reserved only for treatment failures.