Molecular characterization and epidemiology of carbapenem non-susceptible Enterobacteriaceae isolated from the Eastern region of Heilongjiang Province, China

Abstract

BackgroundThe aim of this study was to elucidate the molecular epidemiology of carbapenem non-susceptible Enterobacteriaceae(CNSE) isolated in the Eastern region of Heilongjiang Province, China, and the mechanism of carbapenem resistance.MethodsA total of 53 CNSE isolates were collected in a grade-3 hospital in Heilongjiang province. Sensitivity to antibiotics was determined using the VITEK-2 Compact automatic system. The modified Hodge test (MHT) and modified carbapenem inactivation test (mCIM) were performed for phenotypic identification. Beta-lactamases gene were detected by Polymerase chain reaction(PCR) and DNA sequencing. The transfer of blaNDM and blaKPC was investigated through conjugation experiment. The clinical data of patients were retrospectively reviewed. Homology of Carbapenem-resistant Klebsiella pneumoniae(CRKP) was conducted by multilocus sequence typing (MLST).ResultsCNSE were highly resistant to the majority of antimicrobial agents. The resistance rate was 100% for first, third, fourth generation cephalosporins and enzyme inhibitor compounds. Gentamicin and tobramycin recorded a resistance rate higher than 80%. Less than 30% resistance was detected for amikacin and levofloxacin. Among CNSE 52(98.1%) and 48(90.6%) of CNSE were positive for mCIM and MHT respectively. There were 42 positive blaKPC genes, three blaNDM-1 genes, three blaNDM-5 genes, one blaNDM-7 gene, and six blaIMP-4 genes. Most isolates harbored multiple drug resistance gene, especially as related to extended-spectrum-β-lactamases, blaSHV, blaTEM and blaCTX-M-15 genes.The resistant gene was transferred into recipient Escherichia coli J53 through conjugation in 21.3% (10/47) of the strains. MLST revealed that ST76 (n = 36) was the most predominant clone, followed by ST896, ST323 and ST11. A new one ST 2946 was identity by this study.ConclusionThe carbapenem resistance phenomenon is alarming and blaKPC-2 is the main resistant gene of CNSE in our hospital. This is the first report of an outbreak caused by blaKPC-2 positive K. pneumoniae ST76 in the Eastern region of Heilongjiang Province, China. Relevant departments should implement infection control and prevention measures to avoid further dissemination of the multi drug-resistant bacteria (MDR).

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

“…The relatively higher incidence revealed that the ongoing surveillance is urgently warranted in China. From the clinical perspective, there have been reports of transmission of E. coli in the ICU, 28,29 and clinicians should be vigilant about the potential presence of this species. Our study also confirmed that carbapenemresistant strains were most commonly isolated from patients aged >65 years who were treated in the ICU.…”

Molecular characterization of metallo-β-lactamase- producing carbapenem-resistant Enterobacter cloacae complex isolated in Heilongjiang Province of China

“…Bacterial DNA was extracted using the boiling method. The ß-lactamases type A encoding genes (bla TEM , bla SHV , bla CTX-M-15 , bla CTX-M-, bla kpc9 ), Type B encoding genes (bla NDM − 1 , bla IMP-4 , and bla VIM ), Type D encoding genes (bla OXA-23 , bla OXA-24 , bla OXA-51 , bla OXA − 48 and bla OXA-58 ), and AmpC enzyme encoding genes (bla ACC , bla DHA , bla CMY ) were detected by polymerase chain reaction (PCR) assays, followed by sequencing PCR product as described previously [12].…”

“…Multilocus sequence types (MLST) of seven housekeeping genes (dnaA, fusA, gyrB, leuS, pyrG, rplB, and rpoB) were conducted to investigate the genetic relationships of CREC isolates. Briefly, PCR products were sequenced as described [12], and the DNA sequences were aligned with those in the MLST database (http://pubmlst.org/ ecloacae) to identify allelic numbers and sequence types (ST). Molecular phylogenetic analyses were performed by using the Maximum Likelihood method and evolutionary analyses in MEGA7 software.…”

“…Plasmid DNA was extracted from the CREC isolates with QIAamp DNA Mini prep Kit (Qiagen, Hilden, Germany) and sequenced [12]. A 10-kb fragment library was prepared with PacBio System (Pacific Biosciences, Menlo Park, CA, USA) and assembled using canu software (https://canu.readthedocs.io/en/latest/quickstart.html).…”

Outbreak of KPC-2 Carbapenem-Resistant Klebsiella pneumoniae ST76 and Carbapenem-Resistant K2 Hypervirulent Klebsiella pneumoniae ST375 Strains in Northeast China: Molecular and Virulent Characteristics

“…This retrospective study was conducted on 44 cases presenting with various diseases caused by CRKP from January 2015 to December 2017 at the First Affiliated Hospital of Jiamusi University in Heilongjiang Province, northeast China. The antibiotic susceptibility of 44 CRKP isolates was previously reported [11]. All strains were resistant to carbapenem; the resistance rate to β-lactamase inhibitor combinations, third-generation cephems and aminoglycosides was 93.18%, 100% and 93.18%, respectively.…”