Clonal diversity of Acinetobacter baumannii clinical isolates revealed by a snapshot study

BMC Microbiol. 2013 Oct 22:13:234. doi: 10.1186/1471-2180-13-234.

Abstract

Background: Acinetobacter baumannii is a notorious opportunistic pathogen mainly associated with hospital-acquired infections. Studies on the clonal relatedness of isolates could lay the foundation for effective infection control. A snapshot study was performed to investigate the clonal relatedness of A. baumannii clinical isolates in our local settings.

Results: Among 82 non-repetitive Acinetobacter spp. clinical isolates that were recovered during a period of four days in 13 hospitals in Sichuan, Southwest China, 67 isolates were identified as A. baumannii. Half of the 67 A. baumannii isolates were non-susceptible to carbapenems. bla(OXA-23) was the only acquired carbapenemase gene detected, present in 40 isolates including five carbapenem-susceptible ones. The isolates belonged to 62 pulsotypes determined by PFGE and 31 sequence types (ST) by multi-locus sequence typing. Forty-three isolates belonged to the globally-disseminated clonal complex 92, among which ST75, ST92 and ST208 were the most common sequence types.

Conclusions: Clinical isolates of A. baumannii were diverse in clonality in this snapshot study. However, most of the isolates belonged to the globally-distributed clonal complex CC92. ST75, ST92 and ST208 were the most common types in our region. In particular, ST208 might be an emerging lineage carrying bla(OXA-23).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acinetobacter Infections / epidemiology
  • Acinetobacter Infections / microbiology*
  • Acinetobacter baumannii / classification*
  • Acinetobacter baumannii / drug effects
  • Acinetobacter baumannii / genetics*
  • Acinetobacter baumannii / isolation & purification
  • Anti-Bacterial Agents / pharmacology
  • Carbapenems / pharmacology
  • China / epidemiology
  • Cluster Analysis
  • Cross-Sectional Studies
  • Electrophoresis, Gel, Pulsed-Field
  • Genetic Variation*
  • Genotype
  • Hospitals
  • Humans
  • Molecular Epidemiology
  • Multilocus Sequence Typing
  • beta-Lactam Resistance

Substances

  • Anti-Bacterial Agents
  • Carbapenems