title: Molecular epidemiology of aminoglycosides resistance in acinetobacter spp. With emergence of multidrug-resistant strains.
abstract: BACKGROUND
  Acinetobacter spp. is characterized as an important nosocomial pathogen and increasing antimicrobial resistance. Our aim was to evaluate antimicrobial susceptibility and aminoglycosides resistance genes of Acinetobacter spp. isolated from hospitalized patients.
  
  
  METHODS
  Sixty isolates were identified as Acinetobacter species. The isolates were tested for antibiotic resistance by disc diffusion method for 12 antimicrobials. The presence of aphA6, aacC1 aadA1, and aadB genes were detected using PCR.
  
  
  RESULTS
  From the isolated Acinetobacter spp. the highest resistance rate showed against amikacin, tobramycin, and ceftazidim, respectively; while isolated bacteria were more sensitive to ampicillic/subactam. More than 66% of the isolates were resistant to at least three classes of antibiotics, and 27.5% of MDR strains were resistant to all seven tested classes of antimicrobials. The higher MDR rate presented in bacteria isolated from the ICU and blood samples. More than 60% of the MDR bacteria were resistance to amikacin, ceftazidim, ciprofloxacin, piperacillin/tazobactam, doxycycline, tobramycin and levofloxacin. Also, more than 60% of the isolates contained phosphotransferase aphA6, and acetyltransferase genes aacC1, but adenylyltransferase genes aadA1 (41.7%), and aadB (3.3%) were less prominent. 21.7% of the strains contain three aminoglycoside resistance genes (aphA6, aacC1 and aadA1).
  
  
  CONCLUSIONS
  The rising trend of resistance to aminoglycosides poses an alarming threat to treatment of such infections. The findings showed that clinical isolates of Acinetobacter spp. in our hospital carrying various kinds of aminoglycoside resistance genes.
authors.affiliation: Dept. of Microbiology and Immunology, Kashan University of Medical Sciences, Iran.
authors.forename: R
authors.initials: R
authors.lastname: Moniri
authors.forename: R Kheltabadi
authors.initials: RK
authors.lastname: Farahani
authors.forename: Gh
authors.initials: G
authors.lastname: Shajari
authors.forename: Mh Nazem
authors.initials: MN
authors.lastname: Shirazi
authors.forename: A
authors.initials: A
authors.lastname: Ghasemi
keywords: Acinetobacter spp.; Aminoglycoside resistance genes; Antibiotic resistance; Iran; PCR gene detection