With the dissemination of carbapenemase-producing (CPE) strains worldwide, carbapenem-hydrolyzing enzymes are increasingly reported among isolates of, the first hospital and community-acquired opportunistic pathogen. Here, we have performed an epidemiological survey of carbapenemase-producing (CP-) isolates received at the French National Reference Centre (F-NRC) in 2012 and 2013. Antimicrobial susceptibilities for last-resort antibiotics and antimicrobial compounds commonly used to treat urinary tract infections were determined by broth microdilution. Clonal relationship was assessed using repetitive sequence-based PCR (rep-PCR) and multilocus sequence typing (MLST). From this collection of 140 carbapenemase-producing isolates, 74% produced an OXA-48-like carbapenemase and 21% produced an NDM carbapenemase. A link with a foreign country was suspected for 37% of infected/colonized patients. Most of the isolates were from screening (56%) and from urine samples (26%). Colistin, fosfomycin, and nitrofurantoin possessed the most consistent activity, with 100%, 95%, and 96% isolates susceptible, respectively. A wide diversity of carbapenemase-producing isolates has been found (50 different sequence types [STs]). The most prevalent clones were (i) sequence type 38 (ST38) producing OXA-48 ( = 21), a clone linked to Turkey and North African countries, (ii) ST-90 producing OXA-204 ( = 9), which was responsible for an outbreak related to a contaminated duodenoscope, and (iii) ST-410 producing OXA-181 ( = 5), which was recovered from patients of different geographical origins. These specific clones might be considered high-risk clones for the dissemination of carbapenemases in The wide diversity of STs, combined with the increasing number of CP- isolates received by the F-NRC, suggests a likely dissemination of CP- isolates in the community.
The emergence of colistin-resistant (CoR) is a public health concern, since this antibiotic has become the last line of treatment for infections caused by multidrug-resistant (MDR) Gram negatives. In this study, we have investigated the molecular basis of colistin resistance in 13 MDR strains isolated from 12 patients in a teaching hospital in Sousse, Tunisia. Whole-genome sequencing (WGS) was used to decipher the molecular mechanism of colistin resistance and to identify the resistome of these CoR isolates. It revealed a genome of ca. 5.5 Mbp in size with a G+C content of 57%, corresponding to that commonly observed for These isolates belonged to the 5 different sequence types (ST11, ST15, ST101, ST147, and ST392), and their resistome was composed of acquired β-lactamases, including extended-spectrum beta-lactamase and carbapenemase genes (, ,, and genes), aminoglycoside resistance genes [('), (″)-, ()-, and ()-], and fosfomycin (), fluoroquinolone (-like), chloramphenicol, trimethoprim, and tetracycline resistance genes. All of the isolates were identified as having a mutated gene. Mapping reads with reference sequences of the most common genes involved in colistin resistance revealed several modifications in, , and operons (deletions, insertions, and substitutions) likely affecting the function of these proteins. It is worth noting that among the 12 patients, 10 were treated with colistin before the isolation of CoR No plasmid encoding to genes was found in these isolates. This study corresponds to the first molecular characterization of a collection of CoR strains in Tunisia and highlights that the small-transmembrane protein MgrB is a main mechanism for colistin resistance in .
The rCIM is a rapid (less than 3 h), cheap and accurate test for the detection of CPEs, which can be implemented in low-resource settings, making it a useful tool for microbiology laboratories.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.