title: Prevalence and Molecular Characterization of Plasmid-mediated Extended-Spectrum β-Lactamase Genes (balaTEM, blaCTX and blASHV) Among Urinary Escherichia coli Clinical Isolates in Mashhad, Iran.
abstract: OBJECTIVE
  Extended-spectrum beta-lactamase (ESBL) producing bacteria have an important role in nosocomial infections. Due to the limited availability of information about the molecular epidemiology of ESBL producing bacteria in Mashhad, we decided to investigate about TEM, CTX and SHV ESBLs among urinary Escherichia coli isolates in Mashhad, a city in northeast Iran.
  
  
  METHODS
  One hundred and eleven clinical isolates of E. coli were diagnosed from hospitalized patients in 2009. After performing antibiogram and phenotypic confirmation test, polymerase chain reaction (PCR) was performed by blaTEM, blaSHV and blaCTX primers and restriction digestion was carried out using PstI and TaqI (Fermentas-Lithuania) for confirmation.
  
  
  RESULTS
  ESBL producers of E. coli isolates were 33.3%. Among 37 ESBL-producing isolates, 35 (94.6%), 21 (56.8%) and 5 (13.5%) were shown to have blaCTX, blaTEM and blaSHV, genes respectively. Co-resistance to non-beta lactam antibiotics was observed more with ESBL producers (P < 0.05).
  
  
  CONCLUSIONS
  The results showed that the studied ESBL genes are found with high prevalence and among them blaCTX is more widespread in urine E. coli isolates in Mashhad.
authors.affiliation: Department of Biology, Mashhad Branch, Islamic Azad University, Mashhad, Iran.
authors.forename: Mahboobeh
authors.initials: M
authors.lastname: Nakhaei Moghaddam
authors.forename: Mohammad Mahdi
authors.initials: MM
authors.lastname: Forghanifard
authors.forename: Sheila
authors.initials: S
authors.lastname: Moshrefi
keywords: Antibiotic resistance; Escherichia coli; Extended-spectrum beta-lactamase; Urinary tract infection