Altered blood microbiome in patients with HCV-related decompensated cirrhosis.

BackgroundAltered bacterial translocation is associated with transitioning from compensated to decompensated cirrhosis. Thus, we aimed to study differences in the blood microbiome of HCV-infected patients with and without hepatic decompensation. MethodsWe conducted a cross-sectional study in patients with advanced HCV-related cirrhosis with or without human immunodeficiency virus (HIV) infection (n=88). MiSeq Illumina technology for bacterial 16S rRNA sequencing was used. Non-targeted metabolomics was performed by GC-MS and LC-MS ESI+ and ESI-. ResultsPatients with decompensated cirrhosis had lower levels of richness (Chao1), and alpha diversity (Shannon and Simpson indexes) at phylum level, than patients without decompensation. Likewise, we observed significant differences in beta diversity between groups at phylum, class and order levels, being lower in decompensated cirrhotic patients. Higher relative abundance of Proteobacteria (Fold Change (FC)=1.54, p=0.012), Alphaproteobacteria (FC=1.57, p=0.016) and Sphingomonadales (FC=1.61, p=0.050) were significantly associated with hepatic decompensation. The phylum Proteobacteria was positively correlated with ethanolamine and oleic acid (p=0.005 and p=0.004, respectively) and negatively with p-cresol (p=0.006). In addition, the order Sphingomonadales was also negatively correlated with p-cresol (p=0.001). ConclusionsBlood microbial diversity was significantly decreased in patients with decompensated cirrhosis, who presented an enrichment of Proteobacteria, Alphaproteobacteria, and Sphingomonadales, compared to patients with compensated cirrhosis.