Antimicrobial agents active against carbapenem-resistant Escherichia coli and Klebsiella pneumoniae isolates in Lebanon

Abstract

Introduction: It is not yet clear which antimicrobial agents should be used to treat the ominously increasing infections with carbapenem-resistant (CR) bacteria. We therefore investigated the activity of different antimicrobial agents against CR Escherichia coli and Klebsiella pneumoniae in Lebanon.
 Methodology: This retrospective study assessed the minimum inhibitory concentrations (MICs) of three carbapenems (by Etest), as well as the in vitro activity of eight other antimicrobials (by disk diffusion) against CR E. coli (n = 300) and K. pneumoniae (n = 232) isolates recovered at a major University Medical Center in Lebanon.
 Results: Higher percentages of isolates showing carbapenem MICs of ≤ 8 µg/mL were noted among the CR E. coli compared to the CR K. pneumoniae for ertapenem (48% vs 27%), imipenem (74 % vs 58%) and meropenem (82% vs 63%). Among the eight other antimicrobials, activity was generally higher when the MICs for the three carbapenems were ≤ 8 µg/mL. Regardless of the MIC level of the three carbapenems, very low susceptibility rates (≤ 33%) were noted for ciprofloxacin, trimethoprim-sulfamethoxazole and aztreonam against both E. coli and K. pneumoniae isolates. With Amikacin, higher susceptibility rates were seen against E. coli isolates (81%-97%) than against K. pneumoniae isolates (55%-86%), also reflecting higher activity than gentamicin (44%-54%). The best activity (66%-100%) was observed for tigecycline, colistin and fosfomycin against both CR species.
 Conclusions: Based on the in vitro findings in this study, the combination of a carbapenem showing an MIC of ≤ 8 µg/mL together with an active colistin, tigecycline, or fosfomycin, would offer a promising treatment option for patients infected with CR E. coli or K. pneumoniae.

Activity of ceftolozane/tazobactam against commonly encountered antimicrobial resistant Gram-negative bacteria in Lebanon

“…Antimicrobial susceptibility testing was performed using the Etest for minimal inhibitory concentrations (MICs) determination and the disk diffusion (DD) test as reported before [2]. Both the C/T strips (concentration range ≤ 0.016 and ≥ 256 µg/mL) for MICs determination and the C/T disks (40 µg) were obtained from Liofilchem, Scozia, Italy.…”

“…Antibiotic resistance is an emerging health problem worldwide. Especially concerning are the multidrugresistant (MDR) Gram-negative bacteria mainly Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa [1,2]. One of the main mechanisms of resistance to antibiotics among these bacteria is the production of β-lactamases, which are bacterial enzymes that confer resistance to a wide variety of β-lactam antibiotics depending on the type of β-lactamase enzyme produced [1].…”

A compilation of antimicrobial susceptibility data from a network of 13 Lebanese hospitals reflecting the national situation during 2015–2016

“…A recent review on AMR prevalence in different countries of the Arab world has equally demonstrated increasing rates of resistance among multi-drug and extensively drug-resistant bacteria [3]. Although the Lebanese national AMR data are not well described in literature, Lebanon follows the same global trend of increasing AMR as reported by individual hospital studies [4–9]. In the absence of a standardised national surveillance in Lebanon, relatively large Lebanese hospitals generate yearly reports on their antibiotic susceptibility results of the corresponding year.…”

An unequivocal superbug: PDR Klebsiella pneumoniae with an arsenal of resistance and virulence factor genes

“…This led the Centers for Disease Control and Prevention (CDC) to publish an antibiotic resistance threat report in 2019, classifying carbapenem-resistant Enterobacteriaceae (CRE) as an urgent threat [6]. In Lebanon and the Middle East North Africa (MENA) region, the rates of Gram-negative resistance are very high [7][8][9]. With the raging conflicts in the MENA region, especially the Syrian conflict and due to the transfer of patients from field hospitals at the Lebanese-Syrian border to hospitals within Lebanon, there has been a noticeable increase in the rates of Gram-negative resistant organisms in peripheral towns and later in central Lebanese hospitals.…”