title: Prevalence of PER-1- type Extended-Spectrum Beta-Lactamaes in Clinical Strains of Pseudomonas aeruginosa Isolated from Tabriz, Iran.
abstract: OBJECTIVE
  The aim of this study was to investigate the presence of PER-1-type ESBLs in drug resistant Pseudomonas aeruginosa isolates.
  
  
  METHODS
  During one-year period (2008-2009), following isolation and identification of 56 P. aeruginosa, the E-test method was performed for determination of minimal inhibitory concentration of ceftazidim. The isolates that they had MIC≥16 µg/ml against ceftazidim were used for determination of ESBL-producing by combined disk test (CDT) and double disk synergy test (DDST) methods. Bla PER-1 gene was investigated by PCR. P. aeruginosa KOAS was used as positive control.
  
  
  RESULTS
  Twenty-nine (51.78%) out of fifty six isolates had MIC≥16 µg/ml to ceftazidime, twenty two (75.86%) of them were ESBL producers. Some isolates (27.5%) contained bla PER-1 gene.
  
  
  CONCLUSIONS
  PER-1-type ESBLs producing P.aeruginosa has not been reported previously in but there has been a rather high prevalence of it.
authors.affiliation: Department of Microbiology, Faculty of Medicine, and Research Center of Infectious Diseases and Tropical Medicine, Tabriz University of Medical Sciences, Tabriz Iran.
authors.forename: Mohammad Taghi
authors.initials: MT
authors.lastname: Akhi
authors.forename: Yones
authors.initials: Y
authors.lastname: Khalili
authors.forename: Reza
authors.initials: R
authors.lastname: Ghottaslou
authors.forename: Mohammad
authors.initials: M
authors.lastname: Aghazadeh
authors.forename: Mohammad Hosein I
authors.initials: MH
authors.lastname: Seroush Bar Hagh
authors.forename: Saber
authors.initials: S
authors.lastname: Yousefi
keywords: Combined Disk Test; Double Disk Synergy Test; Extended- Spectrum Beta- Lactamase; PER-1gene; Pseudomonas aeruginosa