Effect of gastric microbiota on quadruple Helicobacter pylori eradication therapy containing bismuth

BACKGROUND: Helicobacter pylori (H. pylori) is an important pathogen that can cause a variety of diseases. Yet, full eradication of H. pylori remains a significant challenge in clinical practice. H. pylori and other microbial communities have complex interactions in the unique gastric microecological environment. However, it is not clear whether the interactions have any effect on the therapeutic effect of H. pylori. AIM: The aim was to investigate the characteristics of the gastric microbiota with H. pylori infection and the influence on the H. pylori eradication treatment. METHODS: Patients with H. pylori infection underwent gastroscopy and received treatment for eradication. The prescription included esomeprazole 20 mg bid, Livzon Dele 220 mg bid, amoxicillin 1000 mg bid, and clarithromycin 500 mg bid for 14 d. Patients who did not respond to treatment and failed eradication were compared with those who achieved eradication by 1:2 propensity matching. High-throughput sequencing of the gastric mucosal microbiota was performed, and the results were evaluated by alpha diversity analysis, beta diversity analysis, species correlation analysis, and metabolic pathway correlation analysis. RESULTS: The eradication rate of all the patients was 95.5% (171/179). Twenty-four patients were enrolled in the study after propensity-matched scoring. There were eight cases in the failure group (patients who did not respond well to therapy) and 16 cases in the success group. The majority phyla in the two groups were the same, and included Proteobacteria, Bacteroides, Firmicutes, Actinomycetes, and Fusobacteria. The microbial diversity in the failure group had a decreasing trend (P = 0.092) and the species abundance was significantly lower (P = 0.031) compared with the success group. The high rate of H. pylori eradication was associated with Rhodococcus, Lactobacillus, and Sphingomonas, as they were significantly enriched in the successful group (P < 0.05). Veronococcus and Cilium were enriched in the mucosa of chronic atrophic gastritis patients compared with chronic superficial gastritis patients (P = 0.0466 and 0.0122, respectively). In both study groups, H. pylori was negatively correlated with other bacterial genera. More bacterial genera were directly related to H. pylori in the successful group compared with the failure group. CONCLUSION: The effectiveness of quadruple H. pylori eradication therapy containing bismuth depended on gastric microbiota, and the high rate of H. pylori eradication was associated with the presence of Rhodococcus, Lactobacillus, and Sphingomonas.