Dissemination of imipenem-resistant Acinetobacter baumannii strains carrying the ISAba1 blaOXA-23 genes in a Chinese hospital.
An outbreak of 95 clinical infections with imipenem-resistant Acinetobacter baumannii in a Chinese hospital was investigated and the carbapenemase-encoding genes and their relationship with ISAba1 of these and a further 16 isolates recovered from the intensive care unit (ICU) environment were analysed. Almost all isolates were resistant to a wide range of antimicrobials; the lowest resistance rates were found for polymyxin E (17.1 %), cefoperazone/sulbactam (30.6 %) and ampicillin/sulbactam (67.6 %). Six pattern types defined by DNA macrorestriction patterns were distinguished among the clinical isolates with dissemination of pattern A (50 isolates) to patients in seven hospital units and pattern B (35 isolates) to eight units; the environmental isolates from ICUs were also of pattern A. All isolates were positive for the bla(OXA-66) and bla(OXA-23) genes. The OXA-23-encoding gene was located 34 bp downstream of ISAba1. No plasmids were detected and conjugal transfer of resistance was not demonstrated. The bla(OXA-23) probe hybridized with 200 and 220 kb ApaI chromosomal fragments for type patterns A and B, respectively.
Zhou
Hua
H
The Key Laboratory of Infectious Disease of the Public Health Ministry, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China.
Pi
Bo-Rui
BR
The Key Laboratory of Infectious Disease of the Public Health Ministry, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China.
Yang
Qing
Q
The Key Laboratory of Infectious Disease of the Public Health Ministry, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China.
Yu
Yun-Song
YS
The Key Laboratory of Infectious Disease of the Public Health Ministry, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China.
Chen
Ya-Gang
YG
The Key Laboratory of Infectious Disease of the Public Health Ministry, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China.
Li
Lan-Juan
LJ
The Key Laboratory of Infectious Disease of the Public Health Ministry, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China.
Zheng
Shu-Sen
SS
The Key Laboratory of Infectious Disease of the Public Health Ministry, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China.
D000151:Acinetobacter Infections / Q000453:epidemiology*; D040981:Acinetobacter baumannii / Q000187:drug effects* / Q000235:genetics*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics*; D002681:China / Q000453:epidemiology; D004196:Disease Outbreaks; D024881:Drug Resistance, Bacterial; D006801:Humans; D015378:Imipenem / Q000494:pharmacology*; D007362:Intensive Care Units; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D001618:beta-Lactamases / Q000235:genetics*
D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D015378:Imipenem; C466679:beta-lactamase OXA-23; D001618:beta-Lactamases