Characteristics of gut microbiota in children with sepsis and influence of probiotic supplementation / 中华微生物学和免疫学杂志

ABSTRACT

Objective:To investigate the characteristics of gut microbiota in children with sepsis and the effects of probiotic intervention.Methods:Thirty-four children with sepsis admitted to the Pediatric Intensive Care Unit of Henan Provincial People′s Hospital were enrolled in this prospective study from May 2019 to July 2020. They were randomly divided into two groups and received conventional treatment (conventional treatment group, n=17) and conventional treatment combined with probiotics (probiotics group, n=17), respectively. Twenty healthy children were selected as healthy control group. The baseline characteristics and sequential organ failure assessment (SOFA) score of all children with sepsis were recorded within 24 h after recruitment. Stool samples were collected 5-7 d after recruitment. High-throughput 16S rRNA gene sequencing was used to detect gut microbiota. Bioinformatic analysis and predictive functional profiling of microbial communities were performed to analyze the differences between groups. Results:The α-diversity and β-diversity indexes showed compared with the healthy control group, the two sepsis groups had lower abundance of gut microbiota, but greater individual differences in bacteria structure. These indexes were improved significantly following probiotic intervention ( P<0.05). At the level of phylum, the proportions of Bacteroidota and Actinobacteriota in the conventional treatment group were the lowest among the three groups, while the proportion of Proteobacteria increased significantly ( P<0.05). At the level of genus, Enterocoddus was the predominant bacterium in the conventional treatment group, while the abundance of Bifidobacterium, Faecalibacterium, Erysipelotrichaceae and Rumimococcus- torques in the probiotics group showed an upward trend ( P<0.05). Differences in the abundance of metabolic pathways, including mitochondrial synthesis, exosomes, mRNA transcription and degradation and cysteine metabolism, could be found between the two sepsis groups. Conclusions:This study revealed that children with sepsis exhibit a dysbiotic microbial community with reduced microbial diversity, declined structural stability, decreased abundance of Bacteroidota and enrichment of Proteobacteria. Probiotic supplementation could elevate the percentage of beneficial symbiotic bacteria and reduce the number of pathogenic bacteria. The differential metabolic pathways might be associated with the mechanism of probiotics in practice.