Combatting resistant enterococcal infections: a pharmacotherapy review

Abstract

The role of enterococci in infectious diseases has evolved from a gut and urinary commensal to a major pathogen of concern. Few options exist for resistant enterococci, and appropriate use of the available agents is crucial. Areas covered: Herein, the authors discuss antibiotics with clinically useful activity against Enterococcus faecalis and E. faecium. The article specifically discusses: antibiotics active against enterococci and their mechanism of resistance, pharmacokinetic and pharmacodynamic principles, in vitro combinations, and clinical studies which focus on urinary tract, intra-abdominal, central nervous system, and bloodstream infections due to enterococci. Expert opinion: Aminopenicillins are preferred over all other agents when enterococci are susceptible and patients can tolerate them. Daptomycin and linezolid have demonstrated clinical efficacy against vancomycin-resistant enterococci (VRE). Synergistic combinations are often warranted in complex infections of high inoculum and biofilms while monotherapies are generally appropriate for uncomplicated infections. Although active against resistant enterococci, the pharmacokinetics, efficacy and safety of tigecycline and quinupristin/dalfopristin can problematical for severe infections. For cystitis, amoxicillin, nitrofurantoin, or fosfomycin are ideal. Recently, approved agents such as tedizolid and oritavancin have good in vitro activity against VRE but clinical studies against other resistant enterococci are lacking.

<p>Antibiotic Resistance and Molecular Epidemiology of Vancomycin-Resistant Enterococci in a Tertiary Care Hospital in Turkey</p>

“…20,32,33 In a multi-center surveillance study, the rates of Q/D resistance of VREfm strains in North America and the European Union were 0.6% and 10%, respectively. 34 Furthermore, reduced susceptibility to Q/D in other countries reportedly ranges from 17.6% to 28.6%. 35 The most common Q/D resistance of enterococci occurs with macrolide-lincosamide-streptogramin B (MLSb), which is mediated by the erm genes.…”

<p>In vitro Antibacterial Activity of Isopropoxy Benzene Guanidine Against Multidrug-Resistant <em>Enterococci</em></p>

“…[5][6][7] Concurrent with the declining discovery rate of novel antibiotics, there are some strains of Enterococci have become resistant to last-resort drugs. [8][9][10] In general, Enterococci are considered as a significant antibiotic resistance threat and pose a risk to public health as a whole.…”

Pharmacodynamics of linezolid-plus-fosfomycin against vancomycin-susceptible and -resistant enterococci in vitro and in vivo of a Galleria mellonella larval infection model

“…VRE has been associated with 2.5 times higher mortality compared with VSE, which might be associated with postponed appropriate antibiotic therapy (5, 6). Infections caused by VRE, incidences of which have been on the rise since 1988, poses significant challenges for infection treatment because there are fewer and fewer available antimicrobial agents (7). VRE has become problematic in the clinical setting due to the given the tendency for easy spreading and challenges in antimicrobial management (8).…”