Why carry out this study?

H. pylori eradication therapy may induce the pathogenesis of various disorders through the changes and dysbiosis in gut microbiota.

Recently, several studies have assessed the impact of H. pylori eradication on the gut microbiota. However, the effects of probiotics supplementation on the eradication rate, homeostasis, and functional potential of gut microbiota after bismuth quadruple therapy are still not clear.

This is the first multicenter randomized trial to show the effect of most common probiotics in China on gut microbiota after bismuth quadruple therapy. We also focused on the specific microbial changes and functional pathways associated with H. pylori eradication outcome.

What was learned from the study?

Our finding showed that bismuth quadruple therapy led to a short-term disturbance of gut microbiota which could be completely recovered by 8 weeks after eradication.

These findings support the safety of bismuth quadruple therapy, since it is recommended as the first-line eradication regimen in China.

Although probiotics supplementation did not increase eradication rates, probiotics supplementation might help to construct a beneficial profile of gut microbiota after eradication therapy.

More importantly, we identified several bacteria taxa and metabolic pathways that are associated with the H. pylori eradication outcome. Thus, supplementation of probiotics is valuable and recommended during bismuth quadruple therapy in China.