Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Nov 21, 2015; 21(43): 12322-12333
Published online Nov 21, 2015. doi: 10.3748/wjg.v21.i43.12322
Effect of rifaximin on gut microbiota composition in advanced liver disease and its complications
Francesca Romana Ponziani, Viviana Gerardi, Silvia Pecere, Francesca D’Aversa, Loris Lopetuso, Maria Assunta Zocco, Maurizio Pompili, Antonio Gasbarrini
Francesca Romana Ponziani, Viviana Gerardi, Silvia Pecere, Francesca D’Aversa, Loris Lopetuso, Maria Assunta Zocco, Maurizio Pompili, Antonio Gasbarrini, Internal Medicine and Gastroenterology, Agostino Gemelli Hospital, 00168 Rome, Italy
Author contributions: Ponziani FR reviewed scientific literature, wrote the paper, revised and approved the final version; Pecere S, Gerardi V, D’Aversa F and Lopetuso L reviewed scientific literature, wrote the paper; Zocco MA and Pompili M revised and approved the final version; and Gasbarrini A designed the review, revised and approved the final version.
Conflict-of-interest statement: The authors have no conflicts of interest to declare.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Correspondence to: Silvia Pecere, MD, Internal Medicine and Gastroenterology, Agostino Gemelli Hospital, via Moscati 31, 00168 Rome, Italy.
Telephone: +39-6-30156265 Fax: +39-6-30157249
Received: June 29, 2015
Peer-review started: July 3, 2015
First decision: August 31, 2015
Revised: September 3, 2015
Accepted: October 17, 2015
Article in press: October 20, 2015
Published online: November 21, 2015

Liver cirrhosis is a paradigm of intestinal dysbiosis. The qualitative and quantitative derangement of intestinal microbial community reported in cirrhotic patients seems to be strictly related with the impairment of liver function. A kind of gut microbial “fingerprint”, characterized by the reduced ratio of “good” to “potentially pathogenic” bacteria has recently been outlined, and is associated with the increase in Model for End-Stage Liver Disease and Child Pugh scores. Moreover, in patients presenting with cirrhosis complications such as spontaneous bacterial peritonitis (SBP), hepatic encephalopathy (HE), and, portal hypertension intestinal microbiota modifications or the isolation of bacteria deriving from the gut are commonly reported. Rifaximin is a non-absorbable antibiotic used in the management of several gastrointestinal diseases. Beyond bactericidal/bacteriostatic, immune-modulating and anti-inflammatory activity, a little is known about its interaction with gut microbial environment. Rifaximin has been demonstrated to exert beneficial effects on cognitive function in patients with HE, and also to prevent the development of SBP, to reduce endotoxemia and to improve hemodynamics in cirrhotics. These results are linked to a shift in gut microbes functionality, triggering the production of favorable metabolites. The low incidence of drug-related adverse events due to the small amount of circulating drug makes rifaximin a relatively safe antibiotic for the modulation of gut microbiota in advanced liver disease.

Keywords: Liver cirrhosis, Gut microbiota, Rifaximin, Hepatic encephalopathy, Spontaneous bacterial peritonitis, Ascites, Endotoxemia, Thrombocytopenia

Core tip: Advanced liver disease is characterized by intestinal dysbiosis, which has been involved in the pathogenesis of complications. Rifaximin is able to improve cognitive tests and practical abilities, to reduce the risk of hepatic encephalopathy (HE) recurrence and the number of HE-related hospitalizations. Rifaximin efficacy seems not associated with major changes in gut bacteria composition but rather with a shift in the microbiome functionality. Rifaximin is useful in the prevention of spontaneous bacterial peritonitis in patients with ascites. Rifaximin reduces endotoxemia and has beneficial effects on cirrhotic patients hemodynamics, reducing the incidence of complications related to portal hypertension.