Characteristics of gastric microbiota in cirrhotic patients with portal hypertension

Abstract

Objective To investigate the structure characteristics, influencing factors and the correlation with clinical parameters of gastric microbiota in cirrhotic patients with portal hypertension. Methods Preoperative gastric mucosa and gastric juice samples were collected from cirrhotic patients undergoing transjugular intrahepatic portosystemic shunt (TIPS) in our hospital from November 2020 to November 2021, and relevant clinical parameters during hospitalization were also obtained. The composition and diversity of gastric microbiota in the patients were analyzed by 16S rRNA high-throughput sequencing. LEfSe analysis was used to search for different bacteria; Redundancy analysis (RDA) was performed to identify the main factors affecting the gastric microbiota community structure; and Spearman correlation analysis was adopted to explore the correlation between the abundance of gastric microflora and clinical parameters. Results Proteobacteria, Actinobacteria, Acidobacteria and Chloroflexi were enriched in gastric mucosa, while Firmicutes and Fusobacteria in gastric juice. The Chao1 index of species in gastric mucosa was significantly higher than that in gastric fluid (P 0.05). PCoA analysis showed that there was statistical difference in community composition between gastric mucosa and gastric juice (P 0.05). RDA analysis suggested that portal pressure gradient (PPG) was the main factor affecting the community structure of gastric mucosa flora (r2=0.683, P < 0.001), and the abundance of Hamadaea and Eikenella were positively correlated with PPG (r=0.633, 0.618, respectively; P < 0.05). Conclusion The microflora structure between gastric mucosa and gastric juice is different in cirrhotic patients with portal hypertension, but there is no significant difference in the species diversity. The composition of gastric mucosal flora in patients with PHG has characteristic changes, and PPG plays an important role in the structure of gastric mucosa microbiota. The relatively increased abundance of Hamadaea and Eikenella in gastric mucosa may be associated with portal hypertension in cirrhosis.

Keywords

• liver cirrhosis
• portal hypertension
• portal hypertensive gastropathy
• gastric microbiota
• 16s rrna