Modulation of duodenal and jejunal microbiota by rifaximin in mice with CCl4-induced liver fibrosis

Rifaximin is a poorly absorbed broad-spectrum antibiotic used for hepatic encephalopathy. Although increased Lactobacillaceae and decreased Bacteroidetes are characteristic of hepatic encephalopathy, rifaximin does not dramatically alter the stool microbiota. Because the antimicrobial effect of rifaximin increases by micellization with bile acids, we hypothesized that rifaximin alters the microbiota in the duodenum and jejunum, where bile acids are abundant. Using CCl4-induced liver fibrosis mice, we analyzed the effect of rifaximin on the microbiota of the duodenum, jejunum, ileum, cecum, and stool.