Carbapenem-resistant Enterobacter cloacae complex in a tertiary Hospital in Northeast China, 2010–2019

Abstract

Background Carbapenem-resistant Enterobacter cloacae complex (CREC) is a new emerging threat to global public health. The objective of the study was to investigate the clinical characteristics and molecular epidemiology of CREC infections in the medical center of northeast China. Methods Twenty-nine patients were infected/colonized with CREC during a ten-year period (2010–2019) by WHONET analysis. Antibiotic susceptibilities were tested with VITEK 2 and micro broth dilution method (for polymyxin B and tigecycline). Carbapenemase encoding genes, β-lactamase genes, and seven housekeeping genes for MLST were amplified and sequenced for 18 cryopreserved CREC isolates. Maximum likelihood phylogenetic tree was built with the concentrated sequences to show the relatedness between the 18 isolates. Results There was a rapid increase in CREC detection rate during the ten-year period, reaching 8.11% in 2018 and 6.48% in 2019. The resistance rate of CREC isolates to imipenem and meropenem were 100.0 and 77.8%, however, they showed high sensitivity to tigecycline, polymyxin B and amikacin. The 30-day crude mortality of CREC infection was 17.4%, indicating that it may be a low-virulence bacterium. Furthermore, molecular epidemiology revealed that ST93 was the predominant sequence type followed by ST171 and ST145, with NDM-1 and NDM-5 as the main carbapenemase-encoding genes. Moreover, E. hormaechei subsp. steigerwaltii and E. hormaechei subsp. oharae were the main species, which showed different resistance patterns. Conclusion Rising detection rate of CREC was observed in a tertiary hospital, which showed heterogeneity in drug resistance patterns, resistance genes, and MLST types. Effective infection prevention and control measures should be taken to reduce the spread of CREC.

Frequent convergence of mcr-9 and carbapenemase genes in Enterobacter cloacae complex driven by epidemic plasmids and host incompatibility

“…Additionally, a majority of MCR-CREC belonged to epidemic clones, e.g. ST171, ST93, ST133, and ST418 [ 48 , 58 , 59 ], and the plasmids encoding MCR or carbapenemases were able to remain stable in ECC and self-transmissible as shown here. Despite that it remains unclear whether the resistance convergence in these epidemic clones has established evolutionary advantages, continuous surveillance is imperative to prevent them from being high-risk clones.…”

Emergence and Transmission of Plasmid-Mediated Mobile Colistin Resistance Gene mcr-10 in Humans and Companion Animals

“…It has been demonstrated that ECC is an opportunistic organism that can survive in a wide range of hosts, such as humans, animals, and plants. Molecular and biochemical analyses of the ECC have uncovered genomic and genotypic heterogeneity, and it now comprises the following Enterobacter species: E. cloacae , E. asburiae , E. hormaechei , E. kobei , E. ludwigii , E. mori , and E. nimipressuralis ( 2 ), of which E. cloacae and E. hormaechei are the most commonly discovered in clinical specimens from humans and animals, respectively ( 3 ). In addition, carbapenemase genes such as bla IMP , bla NDM , bla GIM , or bla KPC of plasmid origin have been identified in the ECC, not only creating the potential risk for transmission but also reducing the effectiveness of the carbapenems ( 4 ).…”

Genetic Characterization of Enterobacter hormaechei Co-Harboring blaNDM-1 and mcr-9 Causing Upper Respiratory Tract Infection

“… 1 , 2 As an opportunistic pathogen, ECC is ubiquitous not only in nature but also in clinical settings and has been associated with various infections, such as bacteremia, respiratory tract infections, wound infections, and urinary tract infections. 3 , 4 …”

“…1,2 As an opportunistic pathogen, ECC is ubiquitous not only in nature but also in clinical settings and has been associated with various infections, such as bacteremia, respiratory tract infections, wound infections, and urinary tract infections. 3,4 The prevalence of carbapenemase-resistant Enterobacteriaceae (CRE) has risen since the 2000s. 5 New Delhi Metalloβ-lactamase (NDM) is a type of Metallo-β-lactamase (MBL) able to hydrolyze most β-lactams (including carbapenems).…”