Survey of Clinical Extended-Spectrum Beta-Lactamase-Producing Enterobacter cloacae Isolates in a Chinese Tertiary Hospital, 2012-2014.
A total of 72 consecutive and nonduplicate clinical extended-spectrum β-lactamase (ESBL)-producing Enterobacter cloacae isolates were collected from our hospital from 2012 to 2014 for analyzing the prevalence of plasmid-mediated quinolone resistance (PMQR) genes, 16S rRNA methyltransferase (16S-RMTase) encoding genes, and carbapenem-hydrolyzing β-lactamase (CHβL) genes, as well as integrons. Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) were carried out to characterize the genetic relatedness. The isolates mainly harbored blaCTX-M(n = 51, 70.8%) and blaSHV(n = 46, 63.9%) genes. High prevalence of PMQR genes qnrA1 (n = 24, 33.3%), qnrB (n = 4, 5.6%), qnrS1 (n = 2, 2.8%), and aac(6')-Ib-cr (n = 21, 29.2%) was observed. Furthermore, CHβLs IMP-4 (n = 6, 8.3%) and IMP-8 (n = 4, 5.6%), as well as class I integrons (n = 29, 40.3%), were found in the ESBL-producing E. cloacae isolates. PFGE revealed 69 pulsotypes. MLST distinguished 44 sequence types (STs) with ST124 (n = 7, 9.7%), ST50 (n = 3, 4.2%), ST45 (n = 3, 4.2%), and ST93 (n = 3, 4.2%) being the predominant STs. The results indicate a possible clonal transmission of ST124 isolates in the hospital that needs further surveillance. The genetic diversity of the other numerous distinctive STs indicates that most of the ESBL-producing E. cloacae in our hospital might arise through stepwise accumulations of multiple drug-resistance determinants in different clones.
Department of Laboratory Medicine, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School , Nanjing, Jiangsu, People's Republic of China .
Xiao-Li
XL
Cao
Department of Laboratory Medicine, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School , Nanjing, Jiangsu, People's Republic of China .
Li
L
Cheng
Department of Laboratory Medicine, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School , Nanjing, Jiangsu, People's Republic of China .
Zhi-Feng
ZF
Zhang
Department of Laboratory Medicine, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School , Nanjing, Jiangsu, People's Republic of China .
Ming-Zhe
MZ
Ning
Department of Laboratory Medicine, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School , Nanjing, Jiangsu, People's Republic of China .
Wan-Qing
WQ
Zhou
Department of Laboratory Medicine, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School , Nanjing, Jiangsu, People's Republic of China .
Kui
K
Zhang
Department of Laboratory Medicine, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School , Nanjing, Jiangsu, People's Republic of China .
Han
H
Shen
D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002681:China / Q000453:epidemiology; D002999:Clone Cells; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D016521:Electrophoresis, Gel, Pulsed-Field; D016972:Enterobacter cloacae / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification; D004756:Enterobacteriaceae Infections / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology; D024841:Fluoroquinolones / Q000494:pharmacology; D015964:Gene Expression Regulation, Bacterial; D006801:Humans; D032023:Integrons; D008826:Microbial Sensitivity Tests; D058885:Multilocus Sequence Typing; D010957:Plasmids / Q000737:chemistry / Q000378:metabolism*; D062486:Public Health Surveillance; D062606:Tertiary Care Centers; D001618:beta-Lactamases / Q000235:genetics* / Q000378:metabolism; D047090:beta-Lactams / Q000494:pharmacology
D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones; D047090:beta-Lactams; D001618:beta-Lactamases
ESBL; Enterobacter cloacae; MLST; PFGE; multidrug resistance