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 genes 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 72.2%, however, they showed high sensitivity to tigecycline, polymyxin B and amikacin. The 30-day crude mortality of CREC infection/colonization was 13.8%, 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. E. hormaechei subsp. steigerwaltii and E. hormaechei subsp. oharae were the main species, which showed different resistance patterns.Conclusions: 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.

Molecular characteristics of global β-lactamase-producing Enterobacter cloacae by genomic analysis

“…Globally, bla CHβLs such as bla KPC (class A), bla NDM/VIM/ IMP (class B) and bla OXA-48 (class D) are of grave clinical concern and proliferating [8]. It was reported that bla NDM-1 and bla NDM-5 were the main bla CHβLs , ST93, ST171 and ST145 was the predominant sequence types (STs) for CREL in a tertiary Hospital in Northeast China during 2010-2019 [9]. Whereas in Japan, bla IMP-1 was the dominant bla CHβLs conferring carbapenem resistance [10], and bla VIM was the main bla CHβLs in France between 2015-2018 [11].…”