The role of Gram-positive and drug-resistant bacteria in bacterial infections in cirrhosis

© Digestive Medicine Research. All rights reserved. Dig Med Res 2021;4:26 | http://dx.doi.org/10.21037/dmr-21-35 Bacterial infections are a frequent complication of cirrhosis, with a 5-fold higher incidence than that reported in the general population (1,2). Infections in cirrhosis are lifethreatening as they increased mortality fourfold; Shortterm mortality is 30% at one month and about 60% at 12 months (2). Despite advances in the understanding of the pathogenetic mechanisms and management, bacterial infections are associated with the development of complications leading to hospitalization of cirrhotic patients in common wards or in intensive care units (ICUs) (2). Types of bacterial infections in cirrhosis are spontaneous bacterial peritonitis (SBP), pneumonia, urinary tract infections, skin or soft tissue infections and spontaneous or secondary bacteremia (1,3). SBP and spontaneous bacteremia are characteristic for patients with decompensated liver cirrhosis and are originated from the intestinal tract (endogenous infections) (3). The pathogenetic process leading to the development of SBP or spontaneous bacteremia is the traverse of viable microorganisms from the intestinal tract through the gut wall to the mesenteric lymph nodes, passing to the systemic circulation (development of spontaneous bacteremia) and entrance to the peritoneal fluid through the l iver (development of SBP). This mechanism was first depicted in 1979 and was named bacterial translocation (4). The components that enhance bacterial translocation in cirrhosis are disturbed bacterial overgrowth, increased gut permeability and impaired gut-associatedlymphatic tissue (5). Gram-negative usually Enterobacteriaceae SBP are the most prevalent bacteria causing SBP (6). Since 1990, a change in epidemiology of type of bacteria associated with infections in cirrhosis was reported. Initially, quinolone-resistant bacteria were observed due to wide use of this family of antibiotics for SBP prophylaxis (7). This phenomenon was followed by a growing rate of infections with Gram-positive bacteria (cocci) (8-10). In a Spanish study of 405 patients with cirrhosis, Grampositive bacteria were isolated in 53% patients overall and in 59% of nosocomial infections (1). Infections by Gram-positive bacteria were associated with hospital environment and interventional techniques such as ligation of esophageal varices, insertion of central catheters and chemoembolization (1,9). The emergence of vancomycinresistant enterococci (VRE) strains was firstly observed in US hospitals and Liver Centers and was attributed to the avoparcin enrichment of the animal food and the transmission to humans through food chain (11). It was reported that VRE distribution varied globally from less than 1% in Finland, France, Iceland and Sweden to 40–50% in Latin America or Ireland and >70% in USA (11). Recently, Piano et al. in a worldwide multicenter study including 1,302 patients with cirrhosis and bacterial or fungal infections found that the global prevalence of Gram-positive bacteria was 38% and differed in geographical areas, being higher in Europe (43%) and lower in Asia (28%) (12). The most important shift in epidemiology is the growing incidence of bacterial infections induced by multi-drug-resistant organisms (MDRO). The MDRO are classified as multidrug-resistant (MDR), extensivelydrug-resistant (XDR) or pandrug-resistant (13). Even though extended-spectrum-b-lactamase-producing Editorial