Susceptibility patterns and molecular epidemiology of multidrug-resistant Acinetobacter baumannii strains from three military hospitals in China

Int J Antimicrob Agents. 2010 Mar;35(3):269-73. doi: 10.1016/j.ijantimicag.2009.10.016. Epub 2009 Dec 29.

Abstract

To date, little has been reported on the susceptibility patterns and molecular characterisation of multidrug-resistant Acinetobacter baumannii (MDRAB) clinical isolates from different Chinese military hospitals. In this study, 49 MDRAB strains were collected from three military hospitals during 2007. The minimum inhibitory concentrations (MICs) of 13 antibiotics were determined for each strain. Genotyping and dendrogram analysis of MDRAB strains were performed using the repetitive sequence-based polymerase chain reaction (rep-PCR) DiversiLab Microbial Typing System. PCR screening was carried out to investigate the distribution of various genes contributing to each resistance phenotype in the main clonal types. The rates of resistance to the majority of antibiotics tested varied between 75.5% and 100%, with the exception of polymyxin B. Two DiversiLab rep-PCR clones (A and B) were widespread in three hospitals in different cities, one clone (D) existed only in two hospitals located in the same city (Beijing), and the other two clones (C and E) were present in only one hospital. In addition, this study shows a high distribution of intI1, ISAba1, bla(OXA-23), bla(ADC), adeB, adeJ, abeM and tet(B) genes, which mediate resistance to structurally unrelated antimicrobials in MDRAB isolates. These results suggest that all isolates were resistant to at least three classes of antibiotics. In addition, clonal dissemination among the three hospitals located in two different cities in China, previously documented in many regions of Europe and Asia-Pacific nations, emphasises the epidemic potential of these MDRAB isolates.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acinetobacter Infections / microbiology*
  • Acinetobacter baumannii / classification*
  • Acinetobacter baumannii / drug effects*
  • Acinetobacter baumannii / isolation & purification
  • Anti-Bacterial Agents / pharmacology*
  • Bacterial Typing Techniques*
  • China
  • Cluster Analysis
  • Cross Infection / microbiology*
  • DNA Fingerprinting
  • DNA, Bacterial / genetics
  • Drug Resistance, Multiple, Bacterial*
  • Genes, Bacterial
  • Hospitals, Military
  • Humans
  • Microbial Sensitivity Tests
  • Molecular Epidemiology
  • Polymerase Chain Reaction / methods
  • Repetitive Sequences, Nucleic Acid

Substances

  • Anti-Bacterial Agents
  • DNA, Bacterial