Comparative analysis of intestinal microbiota distribution characteristics based on metagenomics in patients with hepatitis B cirrhosis with or without ascites

Abstract

Objective: To use metagenomic sequencing to compare the differences in intestinal microbiota species and metabolic pathways in patients with hepatitis B cirrhosis with or without ascites and further explore the correlation between the differential microbiota and clinical indicators and metabolic pathways. Methods: 20 hepatitis B cirrhosis cases [10 without ascites (HBLC-WOA), 10 with ascites (HBLC-WA), and 5 healthy controls (HC)] were selected from the previously studied 16S rRNA samples. Metagenome sequencing was performed on the intestinal microbiota samples. The Kruskal-Wallis rank sum test and Spearman test were used to identify and analyse differential intestinal microbiota populations, metabolic pathways, and their correlations. Results: (1) The overall structure of the intestinal microbiota differed significantly among the three groups (R = 0.19, P = 0.018). The HC group had the largest abundance of Firmicutes and the lowest abundance of Proteobacteria at the genus level. Firmicutes abundance was significantly decreased (P(fdr) < 0.01), while Proteobacteria abundance was significantly increased (P(fdr) < 0.01) in patients with cirrhosis accompanied by ascites; (2) LEfSe analysis revealed that 29 intestinal microbiota (18 in the HBLC-WA group and 11 in the HBLC-WOA group) played a significant role in the disease group. The unclassified Enterobacteriaceae and Klebsiella species in the HBLC-WA group and Enterobacteriaceae in the HBLC-WOA group were positively correlated with the Child-Turcotte-Pugh (CTP) score, prothrombin time, and international normalized ratio score and negatively correlated with albumin and hemoglobin levels (P < 0.05). Escherichia and Shigella in the HBLC-WA group were positively correlated with CTP scores (P < 0.05); (3) The correlation analysis results between the KEGG pathway and 29 specific intestinal microbiota revealed that Enterobacteriaceae and arachidonic acid, α-linolenic acid, glycerolipid metabolism, and fatty acid degradation were positively correlated in the lipid metabolism pathway, while most Enterobacteriaceae were positively correlated with branched-chain amino acid degradation and negatively correlated with aromatic amino acid biosynthesis in the amino acid metabolic pathway. Conclusion: A significant increment of Enterobacteriaceae in the intestines of HBLC-WA patients influenced hepatic reserve function and was associated with amino acid and lipid metabolic pathways. Therefore, attention should be paid to controlling the intestinal microbiota to prevent complications and improve the prognosis in patients with hepatitis B cirrhosis, especially in those with ascites.