Review
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Hepatol. Sep 18, 2015; 7(20): 2264-2273
Published online Sep 18, 2015. doi: 10.4254/wjh.v7.i20.2264
Markers of bacterial translocation in end-stage liver disease
Ioannis Koutsounas, Garyfallia Kaltsa, Spyros I Siakavellas, Giorgos Bamias
Ioannis Koutsounas, Garyfallia Kaltsa, Spyros I Siakavellas, Giorgos Bamias, Academic Department of Gastroenterology, Ethnikon and Kapodistriakon University, School of Medical Sciences, Laikon General Hospital, 11527 Athens, Greece
Author contributions: All authors contributed to this manuscript.
Conflict-of-interest statement: The authors have no conflict 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: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Ioannis Koutsounas, MD, Academic Department of Gastroenterology, Ethnikon and Kapodistriakon University, School of Medical Sciences, Laikon General Hospital, 17 Agiou Thoma Street, 11527 Athens, Greece. john_koutsounas@yahoo.gr
Telephone: +30-210-7456504 Fax: +30-210-7791839
Received: July 2, 2015
Peer-review started: July 7, 2015
First decision: July 27, 2015
Revised: August 13, 2015
Accepted: August 30, 2015
Article in press: August 31, 2015
Published online: September 18, 2015
Processing time: 75 Days and 11.9 Hours
Abstract

Bacterial translocation (BT) refers to the passage of viable bacteria or bacterial products from the intestinal lumen, through the intestinal epithelium, into the systemic circulation and extraintestinal locations. The three principal mechanisms that are thought to be involved in BT include bacterial overgrowth, disruption of the gut mucosal barrier and an impaired host defence. BT is commonly observed in liver cirrhosis and has been shown to play an important role in the pathogenesis of the complications of end stage liver disease, including infections as well as hepatic encephalopathy and hepatorenal syndrome. Due to the importance of BT in the natural history of cirrhosis, there is intense interest for the discovery of biomarkers of BT. To date, several such candidates have been proposed, which include bacterial DNA, soluble CD14, lipopolysaccharides endotoxin, lipopolysaccharide-binding protein, calprotectin and procalcitonin. Studies on the association of these markers with BT have demonstrated not only promising data but, oftentimes, contradictory results. As a consequence, currently, there is no optimal marker that may be used in clinical practice as a surrogate for the presence of BT.

Keywords: End stage liver disease; Cirrhosis; Soluble CD14; Bacterial DNA; Lipopolysaccharides endotoxin; Procalcitonin; Bacterial translocation; Calprotectin; Biomarkers; Lipopolysaccharide-binding protein

Core tip: The exact mechanism behind bacterial translocation in patients with cirrhosis has not been fully elucidated. The discovery of reliable biomarkers for this phenomenon would be of significant clinical importance, as bacterial translocation is closely associated with the development of severe complications. Various molecules have been identified as candidates for serving as markers of bacterial translocation in this patient population. This mini-review attempts to summarize the most recent available data regarding the potential use of such markers as clinical and prognostic tools in the management of end-stage liver disease.