Molecular epidemiology of Acinetobacter baumannii in Iran: endemic and epidemic spread of multiresistant isolates

J Antimicrob Chemother. 2014 Sep;69(9):2383-7. doi: 10.1093/jac/dku045. Epub 2014 Feb 20.

Abstract

Objectives: We examined the molecular epidemiology of Acinetobacter baumannii clinical isolates from two cities (Tehran and Tabriz) of Iran.

Methods: DiversiLab repetitive extragenic palindromic PCR (rep-PCR), multilocus sequence typing and sequence group multiplex PCR were performed. The presence of resistance mechanisms including metallo-β-lactamases, extended-spectrum β-lactamases, OXA carbapenemases, aminoglycoside-modifying enzymes and RNA methylases was also investigated.

Results: DiversiLab rep-PCR identified 11 clusters and 11 singleton isolates. Twelve sequence types (STs), including six novel types, were identified. Sequence groups (SGs) 1-3 as well as five additional banding patterns were detected by multiplex PCR. A local outbreak in a general hospital in Tabriz with an SG1/ST2 profile was identified. Isolates of international clone II showed the highest prevalence and the most heterogeneous combination of resistance determinants.

Conclusions: Several different multiresistant strains of A. baumannii were shown to circulate in Iran. The selection and spread of the SG1/ST2 clone might have been favoured by the acquisition of resistance genes in the absence of adequate infection control measures.

Keywords: DiversiLab rep-PCR; MLST; multidrug resistance.

MeSH terms

  • Acinetobacter Infections / epidemiology*
  • Acinetobacter Infections / microbiology
  • Acinetobacter baumannii / classification*
  • Acinetobacter baumannii / drug effects
  • Acinetobacter baumannii / genetics*
  • Acinetobacter baumannii / isolation & purification
  • Cities / epidemiology
  • Cluster Analysis
  • Drug Resistance, Multiple, Bacterial*
  • Genetic Variation
  • Genotype
  • Humans
  • Iran / epidemiology
  • Molecular Epidemiology
  • Molecular Typing*