Dataset Information

Molecular Mechanisms and Epidemiology of Carbapenem-Resistant Escherichia coli Isolated from Chinese Patients During 2002-2017.

ABSTRACT: Background:The emergence and spread of carbapenem-resistant Escherichia coli (E. coli) pose a serious threat to human health worldwide. This study aimed to investigate the molecular mechanisms underlying carbapenem resistance and their prevalence among E. coli in China. Methods:A collection of 5796 E. coli clinical isolates were collected from the First Affiliated Hospital of Wenzhou Medical University from 2002 to 2017. Sensitivity to antibiotics was determined using the agar dilution method. The detection of carbapenemases production and the prevalence of resistance-associated genes were investigated through modi?ed carbapenem inactivation method (mCIM), PCR and sequencing. The mutations in outer membrane porins genes (ompC and ompF) were also analyzed by PCR and sequencing assays. The effect of efflux pump mechanism on carbapenem resistance was also tested. E. coli were typed by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Results:A total of 58 strains (1.0%) of carbapenem-resistant E. coli were identified. The strains carrying bla KPC-2 and bla NDM accounted for 22.4% (13/58) and 51.7% (30/58), respectively. Among bla NDM- positive strains, 27 bla NDM genes were assigned to bla NDM-5, while the remaining three strains were bla NDM-1, whereas bla VIM, bla IMP, bla OXA-48, and bla SHV were not found. The CTX-M-type ?-lactamase genes accounted for 96.6% (56/58). In addition, bla TEM-1 genes were identified in 58.6% of tested strains. In carbapenem-resistant isolates, mutations in OmpC (the majority of mutated sites were D192G and Q104_F141del, accounting for 54.5%) and OmpF (large deletions S75_V127del, W83_D135del and Q88_D135del) were detected. Of note, the antibiotic resistance was not associated with overexpression of efflux pump. Moreover, MLST categorized the 58 carbapenem-resistant isolates into 19 different sequence types. PFGE analysis revealed that homology among the carbapenem-resistant isolates was low and sporadic. Conclusion:The bla NDM was the principal resistance mechanism of carbapenem-resistant E. coli in the hospital. bla NDM-5 is becoming a new threat to public health and the alteration of outer membrane porins might help further increase the MIC of carbapenem.

SUBMITTER: Tian X

PROVIDER: S-EPMC7035005 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Molecular Mechanisms and Epidemiology of Carbapenem-Resistant <i>Escherichia</i> <i>coli</i> Isolated from Chinese Patients During 2002-2017.

Tian Xuebin X Zheng Xiangkuo X Sun Yao Y Fang Renchi R Zhang Siqin S Zhang Xiucai X Lin Jie J Cao Jianming J Zhou Tieli T

Infection and drug resistance 20200217

<h4>Background</h4>The emergence and spread of carbapenem-resistant Escherichia coli (<i>E. coli</i>) pose a serious threat to human health worldwide. This study aimed to investigate the molecular mechanisms underlying carbapenem resistance and their prevalence among <i>E. coli</i> in China.<h4>Methods</h4>A collection of 5796 <i>E. coli</i> clinical isolates were collected from the First Affiliated Hospital of Wenzhou Medical University from 2002 to 2017. Sensitivity to antibiotics was determin ...[more]

PMID: 32110061

Similar Datasets

Project description:BackgroundThe emergence of carbapenem-resistant Enterobacterales (CRE) continues to threaten public health due to limited therapeutic options. In the current study the incidence of carbapenem resistance among the 104 clinical isolates of Escherichia coli and the genomic features of carbapenem resistant isolates were investigated.MethodsThe susceptibility to imipenem, tigecycline and colistin was tested by broth dilution method. Susceptibility to other classes of antimicrobials was examined by disk diffusion test. The presence of blaOXA-48, blaKPC, blaNDM, and blaVIM carbapenemase genes was examined by PCR. Molecular characteristics of carbapenem resistant isolates were further investigated by whole-genome sequencing (WGS) using Illumina and Nanopore platforms.ResultsFour isolates (3.8%) revealed imipenem MIC of ≥32 mg/L and positive results for modified carbapenem inactivation method and categorized as carbapenem resistant E. coli (CREC). Colistin, nitrofurantoin, fosfomycin, and tigecycline were the most active agents against all isolates (total susceptibility rate of 99, 99, 96 and 95.2% respectively) with the last three compounds being found as the most active antimicrobials for carbapenem resistant isolates (susceptibility rate of 100%). According to Multilocus Sequence Type (MLST) analysis the 4 CREC isolates belonged to ST167 (n = 2), ST361 (n = 1) and ST648 (n = 1). NDM was detected in all CREC isolates (NDM-1 (n = 1) and NMD-5 (n = 3)) among which one isolate co-harbored NDM-5 and OXA-181 carbapenemases. WGS further detected blaCTX-M-15, blaCMY-145, blaCMY-42 and blaTEM-1 (with different frequencies) among CREC isolates. Co-occurrence of NDM-type carbapenemase and 16S rRNA methyltransferase RmtB and RmtC was found in two isolates belonging to ST167 and ST648. A colistin-carbapenem resistant isolate which was mcr-negative, revealed various amino acid substitutions in PmrB, PmrD and PhoPQ proteins.ConclusionAbout 1.9% of E. coli isolates studied here were resistant to imipenem, colistin and/or amikacin which raises the concern about the outbreaks of difficult-to-treat infection by these emerging superbugs in the future.

Project description:ObjectiveThis retrospective study was conducted to determine the prevalence and molecular epidemiology characteristics of carbapenem-resistant Escherichia coli (CRE).MethodsA total of 593 Escherichia coli (E. coli) isolates were recovered from pigs and urban river from 2009 to 2014 in Heilongjiang Province of China. Forty CRE including 22 strains isolated from fecal samples of pigs and 18 strains isolated from water samples were selected. PCR detection of resistance determinants, multi-locus sequence typing (MLST), pulsed-field gel electrophoresis (PFGE), and phylogenetic groups were performed to characterize CRE isolates. Conjugation experiments, plasmid stability testing, PCR-based replicon typing (PBRT), and PCR mapping were conducted to analyze bla NDM-carrying plasmids. In vitro time-growth studies and competition experiments were carried out to assess the fitness impact of NDM carriage.ResultsFive NDM-1-positive E. coli isolates were identified from water samples. Genetic environment analysis revealed that a cluster of genes (ISAba125-bla NDM-1-ble MBL-ΔtrpF) was detected in all of the NDM-1-positive isolates. Conjugation assays showed that bla NDM-1 could be successfully transferred to E. coli J53 from 5 donor strains at frequencies of 4.6×10-5 to 2.6×10-2. The plasmids from all transconjugants belonged to different plasmid replicon types including IncA/C (n=2), IncFII (n=1) and IncX3 (n=2). In vitro time-growth studies revealed that bla NDM-1 did not have a significant impact on cell proliferation. Meanwhile, competition experiments showed that the acquisition of bla NDM-1 can place an energy burden on the bacterial host and incur fitness cost. However, plasmid stability testing showed that bla NDM-1-carrying plasmid remained stable in the hosts after seven passages without antimicrobial selection.ConclusionThe study revealed the early molecular epidemiology and dissemination characteristics of CRE. In addition, the overall antimicrobial resistance in E. coli recovered from water samples is higher than the strains isolated from fecal samples of pigs. Furthermore, we isolated and identified five NDM-1-producing E. coli strains from water samples.

Dataset Information

Molecular Mechanisms and Epidemiology of Carbapenem-Resistant Escherichia coli Isolated from Chinese Patients During 2002-2017.

Publications

Molecular Mechanisms and Epidemiology of Carbapenem-Resistant <i>Escherichia</i> <i>coli</i> Isolated from Chinese Patients During 2002-2017.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets