<p>Microbiological Characteristics of Carbapenem-Resistant <em>Enterobacteriaceae</em> Clinical Isolates Collected from County Hospitals</p>

Abstract

To investigate the molecular characteristics of carbapenem-resistant Enterobacteriaceae (CRE) from county hospitals in China. Materials and Methods: Forty-three sequential non-duplicate CRE strains (including 33 Klebsiella pneumoniae isolates, 4 Enterobacter cloacae isolates, 3 Escherichia coli isolates, 1 Serratia marcescens, 1 Morganella morganii and 1 Citrobacter freundii) were collected from 4 county hospitals and 2 municipal hospitals. Antimicrobial susceptibility testing was conducted by broth microdilution method, using 3-aminophenylboronic acid and EDTA and the modified carbapenem inactivation method (mCIM) to screen phenotype of carbapenemase. β-Lactamases were characterized by polymerase chain reaction (PCR) and DNA sequencing. The transferability of bla NDM-5 was investigated by transformation experiment. Clonal relatedness was evaluated by pulsed-field gel electrophoresis and multilocus sequence typing. Results: The results of antimicrobial susceptibility testing indicated that 43 CRE strains were resistant to most of the antimicrobial agents, except tigecycline and colistin. Overall, 93%, 93%, and 97.7% of these strains were resistant to imipenem, meropenem, and ertapenem, respectively. PCR and DNA sequencing indicated that 67.4% (29/43) were bla KPC-2 positive isolates, in which 3.4% (1/29) was coproduced with bla NDM-1. In addition, 7.0% (3/ 43), 4.7% (2/43), 4.7% (2/43), 2.3% (1/43), 2.3% (1/43) were bla NDM-1 , bla NDM-16 , bla NDM-4 , bla NDM-5 , bla IMP-4 positive isolates, respectively. The 29 bla KPC-2-positive isolates belonged to 12 different PFGE type and designated as ST11 (n=20) and ST15, ST39, ST116, ST667, ST2245, ST2338. The plasmid bearing bla NDM-5 could be transferred into recipient E. coli J53 through transformation. Conclusion: Our study indicated the dissemination of CRE between the tertiary hospitals and secondary hospitals.

Multidrug-Resistant Klebsiella pneumoniae Causing Severe Infections in the Neuro-ICU

“…The high prevalence of polyresistant isolates in our study was associated with antimicrobial resistance genes. The isolates of Group A carried ESBL genes bla CTX-M (22/29), carbapenemase genes bla OXA-48 (12/29), and bla KPC-2 (1/29), which correspond to the reports from Greece and China [ 27 , 29 , 30 ]. Moreover, four isolates in Group A carrying the only bla SHV were identified (ST218 and ST86).…”

<p>Emergence of NDM-5-Producing Carbapenem-Resistant <em>Klebsiella pneumoniae</em> and SIM-Producing Hypervirulent <em>Klebsiella pneumoniae</em> Isolated from Aseptic Body Fluid in a Large Tertiary Hospital, 2017–2018: Genetic Traits of <em>bla</em>NDM-Like and <em>bla</em>SIM-Like Genes as Determined by NGS</p>

“…Carbapenems are used as a last resort to treat CRKP infections. 3 Worryingly, in our study, more than 80% of CRKP patients had high resistance to carbapenems. The major cause in carbapenem-resistance was CRKP strains carrying different resistance genes.…”

“…10,13 Hence, the diversity of carbapenemases among CRKP strengthens the difficulty for infection control. 3,36 The remaining strains without carbapenemase resistance genes have the same resistant rates with the strains carrying carbapenemase. This suggests that the resistance to the antibiotics might attribute to new mechanisms and further studies should be conducted.…”

“…1,2 KP has earned notoriety as resistance to "last resort" antimicrobials: carbapenems. 3,4 From the China Network Antibacterial Surveillance Center, the carbapenem antibiotics usage density (AUD, defined as DDDs/per 100 patient-days) increased from 2.04 in 2013 to 3.38 in 2017. According to CHINET, the rates of KP resistance to imipenem and meropenem increased from 10.3% and 14.1% in 2013 to 25% and 26.3% in 2018, respectively.…”

Carbapenemase-Producing Klebsiella pneumoniae From Transplanted Patients in Brazil: Phylogeny, Resistome, Virulome and Mobile Genetic Elements Harboring blaKPC–2 or blaNDM–1

“…On the other hand, other Brazilian studies described the presence of ST15 CP-Kp isolates, but to the best of our knowledge, isolates of these studies were not associated to bla NDM– 1 , as described here ( Gonçalves et al, 2017 ; Andrade et al, 2018 ). ST39 was not reported in previous studies with isolates obtained from patients in Brazil, and only individual cases of ST39 producing bla KPC– 2 or bla NDM– 16 were reported in two different studies from China ( Liu et al, 2017 ; Xie et al, 2020 ).…”