Overview of the microbiota in the gut-liver axis in viral B and C hepatitis

Table 1 Microbiota changes in different studies regarding hepatic B and C virus

	Changes of gut microbiota in patients vs healthy subjects	Ref.
Type of HBV infection
Chronic HBV infection	↓ Bacteroidetes and Firmicutes; ↑ Proteobacteria and Actinobacteria	Chen et al[117]
	↑ Bifidobacterium dentium; ↓ Bifidobacterium catenulatum and longum	Xu et al[118]
	↑ Veillonellaceae; ↓ Lachnospiraceae, Rikenellaceae, Ruminococcaceae	Wang et al[119]
HBV liver cirrhosis	↓↓↓ Bacteroidetes and Firmicutes; ↑↑↑ Proteobacteria and Actinobacteria	Chen et al[117]
Decompensated HBV cirrhosis	↓ Bifidobacteria/Enterobacteriaceae ratio; ↑ Enterobacteriaceae; ↓ Firmicutes (F.prausnitzii, Clostridium clusters XI and XIVab, Bifidobacterium); ↓ Bacteroidetes	Lu et al[120]
HBV related hepatocellular carcinoma	↓ Proteobacteria; ↑ Prevotella, Phascolarctobacterium, Anaerotruncus; ↑ Proteus, Veillonella, Prevotella 2, Barnesiella and Ruminococcaceae spp.	Liu et al[121]
Type of HCV infection
Chronic HCV infection without cirrhosis	↑ Veillonella spp., Lactobacillus spp., Streptococcus spp. and Alloprevotella spp.; ↓ Bilophila spp., Clostridium IV spp., Clostridium XlVb spp., Mitsuokella spp. and Vampirovibrio spp.; No changes: Akkermansia spp., Bifidobacterium spp., Escherichia/Shigella spp., Haemophilus spp., Micrococcus spp. and Weissella spp.	Heidrich et al[122]
Chronic HCV infection with cirrhosis	↑↑↑ Veillonella spp., Lactobacillus spp., Streptococcus spp. and Alloprevotella spp.; ↓↓↓ Bilophila spp., Clostridium IV spp., Clostridium XlVb spp., Mitsuokella spp. and Vampirovibrio spp.; ↑↑↑ Akkermansia spp., Bifidobacterium spp., Escherichia/Shigella spp., Haemophilus spp., Micrococcus spp. and Weissella spp.	Heidrich et al[122]
Stage 4 HCV infection (cirrhosis)	↓ Firmicutes; ↑ Prevotella, Faecalibacterium (F. prausnitzii); ↑ Acinetobacter; ↑ Veillonella	Aly et al[123]

HBV: Hepatitis B virus; HCV: Hepatitis C virus.