The Effect of Probiotics Supplementation on Gut Microbiota After Helicobacter pyloriEradication: A Multicenter Randomized Controlled Trial

Introduction: Helicobacter pylorieradication therapy may lead to the perturbation of gut microbiota. We aim to investigate the impact of probiotics on eradication rate and gut microbiota during eradication therapy. Methods: A total of 162 patients receiving bismuth quadruple therapy were enrolled and randomly assigned to groups given probiotics (n= 83) or placebo (n= 79) for 4 weeks. Fecal samples were collected before treatment and 2, 4, 6, and 8 weeks after eradication therapy. Gut microbiota was analyzed by 16S rRNA high-throughput sequencing. Results: The eradication rates in the placebo and probiotics group were 82.43% and 87.01%, respectively (P> 0.05). Compared with baseline, alpha and beta diversity was significantly altered 2 weeks after eradication in both groups, which was restored at week 8. There were no significant differences in diversity between the two groups. H. pylorieradication therapy resulted in enrichment of some detrimental bacteria taxa such as Shigella, Klebsiella, and Streptococcus, while probiotics supplementation could rapidly restore these taxa levels after eradication and increase the taxa of Bacillusand Lactobacillales. Functional analysis revealed that lipopolysaccharide biosynthesis and polymyxin resistance pathways were significantly enriched after eradication, while probiotics supplementation mainly enriched the cofactors and vitamins metabolism pathways. Increased relative abundances of Roseburiaand Dialisterwere associated with the positive eradication outcome. Conclusions: Probiotics supplementation might help to construct a beneficial profile of gut microbiota after eradication therapy. Specific bacteria taxa are associated with H. pylorieradication outcome. These findings may be of value in rational use of probiotics during H. pylorieradication. Trial Registration: Chinese Clinical Trial Registry, ChiCTR1900022116.