eng Oriental Scientific Publishing Company Biosciences Biotechnology Research Asia 0973-1245 2016-06-22 12 Spl.Edn.2 821 826 10.13005/bbra/2265 13693 article Mohammad Saram 1 Mohammad Reza Nahaei 1 Department of Biology, Ahar Branch, Islamic Azad University, Ahar, Iran. Klebsiella pneumonia is an opportunistic pathogen which causing important nosocomial infection such as urinary tract infections, pneumonia, septicemia and soft tissue infections. Studies have shown that today in the world K. pneumoniae strains with multiple antibiotic- resistance are growing quickly and continuous use of antibiotics and selective pressure caused by these factors cause resistance to these category of antibiotics in bacteria.In this study fromApril, 2014 to November, 2014120 isolated of Klebsiella pneumoniae were isolated from hospitalized patients in Ardabil. Antibiotic susceptibility pattern of isolates toward isolates, at first in term of producing Betalactamase wide range were screenedaccording to CLSI recommendations and through disk agar diffusion method. Then Candida isolated producing Beta-lactamase wide range was confirmed with combined disk method in term of producing ESBL. Positive isolates in term of producing ESBL by PCR for the presence of genes blaTEM, blaSHV, blaCTX-M- 1, blaCTX-M-2, blaCTX-M-8 and blaCTX-M-9 were examined. A total of 120 isolates of Klebsiella pneumonia, 79 isolates had reduced susceptibility to the antibiotic of screening phase that 61 isolates (50.8%) were positive for ESBL production. The frequency of genes blaTEM, blaSHV, bla CTX-M-1 was in order 34 isolates (55.7%), 24 isolates (39.3%), 47 isolates (77.04%) and in none of the isolates genes of blaCTX- M-2, blaCTX-M-8 and blaCTX-M-9 was observed. According to high prevalence of isolatesproducing wide range beta-lactamases in the studied hospitals, primary identification of resistant isolates and following them in order to prevent their prevalence is more important. Also applying appropriate treatment strategies and proper and logical prescription of anti-biotic by doctors is also important to control them. https://www.biotech-asia.org/vol12_nospl_edn2/the-frequency-of-klebsiella-pneumoniae-strains-producing-extended-spectrum-beta-lactamases-esbl-with-phenotypic-and-genotypic-methods-in-hospitals-of-ardebil/ Klebsiella pneumoniae strains; Phenotypic; genotypic; extended-spectrum beta-lactamases