title: Evaluate the frequency distribution of nonadhesive virulence factors in carbapenemase-producing Acinetobacter baumannii isolated from clinical samples in Kermanshah.
abstract: BACKGROUND
  Acinetobacter baumannii which is a Gram-negative bacterium can cause several different infections. The appearance of carbapenemase-producing A. baumannii in recent years has made the treatment process more difficult. The identification of virulence factors (VFs), such as nonadhesives in A. baumannii, helps to fight against related infections.
  
  
  METHODS
  A total of 104 samples from teaching hospitals in Kermanshah, Iran, were collected during a 24 months period (2011-2013). Sample identification was first carried out by biochemical tests, and then their susceptibility to carbapenems was determined using the Kirby-Bauer method. For confirmation of carbapenemase-producing A. baumannii, polymerase chain reaction (PCR) was done for carbapenemase-encoding genes. In addition, the frequency of nonadhesive VFs in carbapenemase-producing isolates was determined by PCR.
  
  
  RESULTS
  There were 50 isolates that were identified as carbapenemase-producing A. baumannii. The PCR results showed; 40 isolates (80%) for traT, 17 isolates (34%) for cvaC, and 8 isolates (16%) for iutA, and these encode serum resistance, colicin V and aerobactin, respectively. No significant correlation was observed between these three genes.
  
  
  CONCLUSIONS
  The mechanism of A. baumannii virulence has always been in question. The role of VFs has also been recognized in other Gram-negative bacteria. According to the prevalence of traT, cvaC and iutA, as nonadhesive VFs, we can suggest that they could be the main mechanism of carbapenemase-producing A. baumannii pathogenesis.
authors.affiliation: Department of Microbiology, School of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran.
authors.forename: Parviz
authors.initials: P
authors.lastname: Mohajeri
authors.affiliation: Department of Pharmacology, Student Research Committee, Kermanshah University of Medical Sciences, Kermanshah, Iran.
authors.forename: Saba
authors.initials: S
authors.lastname: Sharbati
authors.affiliation: Department of Microbiology, Student Research Committee, Kermanshah University of Medical Sciences, Kermanshah, Iran.
authors.forename: Abbas
authors.initials: A
authors.lastname: Farahani
authors.affiliation: Department of Pharmacology, Student Research Committee, Kermanshah University of Medical Sciences, Kermanshah, Iran.
authors.forename: Zhaleh
authors.initials: Z
authors.lastname: Rezaei
keywords: Acinetobacter baumannii; carbapenemase-producing; nonadhesive; virulence factor