Abstract:Objective To study the characteristics of gut microbiota and its association with the activity of β-glucuronidase (β-GD) in neonates with hyperbilirubinemia. Methods A total of 50 neonates with hyperbilirubinemia who were admitted in January to December, 2018, were enrolled as the hyperbilirubinemia group, and 30 neonates without hyperbilirubinemia were enrolled as the control group. The 16S rRNA high-throughput sequencing method was used to compare gut microbiota between the two groups. The phenolphthalein-glucuronic acid substrate method was used to measure the activity of β-GD in the intestinal tract of neonates with hyperbilirubinemia before and after treatment. Results The comparison of the distribution of gut microbiota at the genus level showed a significant difference in the abundance of 52 bacteria between the hyperbilirubinemia and control groups before treatment (P < 0.05), as well as a significant difference in the abundance of 42 bacteria between the hyperbilirubinemia group on day 3 after treatment and the control group on day 3 after enrollment (P < 0.05). After treatment, the hyperbilirubinemia group had significant reductions in the content of Escherichia and Staphylococcus in the intestinal tract (P < 0.05) and the activity of β-GD in feces (P < 0.05). The activity of β-GD in feces was positively correlated with the abundance of Staphylococcus and Escherichia before and after treatment in the neonates with hyperbilirubinemia (rs=0.5948-0.7245, P < 0.01). Conclusions There are differences in gut microbiota between the neonates with hyperbilirubinemia and those without hyperbilirubinemia. The activity of β-GD in feces is positively correlated with the abundance of Staphylococcus and Escherichia in neonates with hyperbilirubinemia. Gut microbiota may affect the development of neonatal hyperbilirubinemia by regulating the activity of β-GD. The determination and analysis of gut microbiota and β-GD activity may have certain clinical significance for the early assessment of the development of neonatal hyperbilirubinemia.