Two distinct clones of carbapenem-resistant Acinetobacter baumannii isolates from Korean hospitals

Diagn Microbiol Infect Dis. 2009 Aug;64(4):389-95. doi: 10.1016/j.diagmicrobio.2009.03.029.


We investigated the characteristics of 48 carbapenem-resistant Acinetobacter baumannii isolates collected from 5 tertiary care hospitals in Korea by multilocus sequencing typing, pulsed-field gel electrophoresis, and polymerase chain reaction amplification of the antimicrobial resistance determinants. We identified 2 distinct main clones of carbapenem-resistant A. baumannii isolates, which showed different antimicrobial resistance profiles and are also differentiated by the kinds of oxacillinase (OXA) carbapenemases and Acinetobacter-derived cephalosporinase (ADC) beta-lactamases. One main clone, ST22:A, had 27 carbapenem-resistant isolates (56.3%), showed high polymyxin B and colistin resistances (33.3% and 37.0%, respectively), and contained both bla(OXA-51-like) and bla(OXA-23-like) genes and the bla(ADC-29) or bla(ADC-30) gene. In contrast, the other main clone, ST28:B, included 15 isolates (31.3%), showed complete susceptibilities to polymyxin B and colistin, and contained only the bla(OXA-51-like) gene and bla(ADC-31) or bla(ADC-32) genes. The distribution of these main carbapenem-resistant A. baumannii clones did not relate to locality, indicating that they are widespread in Korean hospitals. In addition, we found new types of PER beta-lactamases, PER-6.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acinetobacter Infections / microbiology*
  • Acinetobacter baumannii / classification*
  • Acinetobacter baumannii / enzymology
  • Acinetobacter baumannii / genetics*
  • Acinetobacter baumannii / isolation & purification
  • Anti-Bacterial Agents / pharmacology*
  • Bacterial Proteins / genetics
  • Bacterial Typing Techniques / methods
  • Carbapenems / pharmacology*
  • Cross Infection / microbiology*
  • DNA Fingerprinting / methods
  • DNA, Bacterial / chemistry
  • DNA, Bacterial / genetics
  • Electrophoresis, Gel, Pulsed-Field / methods
  • Hospitals
  • Humans
  • Korea
  • Molecular Sequence Data
  • Polymerase Chain Reaction / methods
  • Sequence Analysis, DNA
  • beta-Lactam Resistance*
  • beta-Lactamases / genetics


  • Anti-Bacterial Agents
  • Bacterial Proteins
  • Carbapenems
  • DNA, Bacterial
  • beta-Lactamases

Associated data

  • GENBANK/EU687473