Mohammad Taghi Akhi - Department of Microbiology, Faculty of Medicine, and Research Center of Infectious Diseases and Tropical Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
Yones Khalili - Department of Microbiology, Faculty of Medicine, and Research Center of Infectious Diseases and Tropical Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
Reza Ghottaslou - Department of Microbiology, Faculty of Medicine, and Research Center of Infectious Diseases and Tropical Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
Mohammad Aghazadeh - Department of Microbiology, Faculty of Medicine, and Research Center of Infectious Diseases and Tropical Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
Mohammad hosein Seroush Bar Haghi - Department of Microbiology, Faculty of Medicine, and Research Center of Infectious Diseases and Tropical Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
Saber Yousefi - Department of Clinical Laboratory Sciences, Faculty of Paramedicine, Urmia University of Medical Science

Objective(s) The aim of this study was to investigate the presence of PER-۱-type ESBLs in drug resistant Pseudomonas aeruginosa isolates. Materials and Methods During one-year period (۲۰۰۸-۲۰۰۹), following isolation and identification of ۵۶ P. aeruginosa, the E-test method was performed for determination of minimal inhibitory concentration of ceftazidim. The isolates that they had MIC≥۱۶ 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-۱genewas investigated by PCR.P. aeruginosa KOAS was used as positive control. Results Twenty-nine (۵۱.۷۸%) out of fifty six isolates had MIC≥۱۶ µg/ml to ceftazidime, twenty two (۷۵.۸۶%) of them were ESBL producers. Some isolates (۲۷.۵%) contained bla PER-۱ gene. Conclusion PER-۱-type ESBLs producing P.aeruginosa has not been reported previously in Tabriz but there has been a rather high prevalence of it.

Combined Disk Test, Double Disk Synergy Test, Extended- Spectrum Beta- Lactamase, PER-۱gene, Pseudomonas aeruginosa