Long-term changes in the gut microbiota before and after bismuth quadruple therapy or concomitant therapy in children with peptic ulcers receiving Helicobacter pylori eradication.

Background: Helicobacter pylori (H. pylori) is a gram-negative spiral bacterium that can cause peptic ulcers. The effects of bismuth quadruple therapy and concomitant therapy on fecal ecology among children with peptic ulcers remain largely unknown. According to guidelines, these patients should be treated. Therefore, the aim of this study is to investigate the short- and long-term effects of bismuth quadruple therapy and concomitant therapy on gut microbiota in children with peptic ulcer disease (PUD).

Methods: Forty-two patients with PUD were enrolled and collected their fecal samples in Shanghai. A 16S ribosomal RNA (rRNA)-based analysis was conducted. The impacts of bismuth quadruple therapy and concomitant therapy on the gut microbiota were compared before eradication and at 2, 6 and 52 weeks (12 months) after eradication.

Results: Whatever bismuth quadruple therapy and concomitant therapy, the diversity and richness of gut microbiota markedly decreased and fecal microbiota structure markbly changed at week 2. At week 6, the composition a returned to the baseline level; nevertheless, the diversity and richness gradually returned to baseline until week 52. Compared to those in the healthy control group, the relative abundances of 90% (18/20) of the bacterial genera differed at week 2, 15% (3/20) of the bacterial genera differed at week 6, and 10% (2/20) of the bacterial genera were not restored at week 52.

Conclusions: Both bismuth-containing therapy and concomitant therapy resulted in transient changes of the gut microbiota in Chinese children, and these changes nearly returned to pre-eradication levels 1 year after eradication, suggesting the long-term safety of H. pylori therapy in children with peptic ulcers.