title: The Prevalence of TEM and SHV Genes among Extended-Spectrum Beta-Lactamases Producing Escherichia Coli and Klebsiella Pneumoniae.
abstract: OBJECTIVE
  Production of extended-spectrum beta-lactamases (ESBLs) by enteric bacteria continues to be a major problem in hospitals and community. ESBLs producing bacteria cause many serious infections including urinary tract infections, peritonitis, cholangitis and intra-abdominal abscess. The aim of this study was to determine the prevalence of ESBLs producing Escherichia coli and Klebsiella pneumoniae bacteria isolated from clinical samples of patients attending Imam Reza and Ghaem University Hospitals, Mashhad, Northeast of Iran.
  
  
  METHODS
  During 2009 and 2010, 82 strains of E. coli and 78 strains of K. pneumoniae were isolated from out-patients and hospitalized patients and they were examined by Oxoid combination disk test and PCR methods.
  
  
  RESULTS
  We found that 43.9% of E. coli and 56.1% of K. pneumoniae produced ESBLs. The frequency of SHV and TEM among the ESBLs producing isolates were 14.4% and 20.6%, respectively. Ratios of ESBLs positive isolates from out-patients to hospitalized patients were 24/33.
  
  
  CONCLUSIONS
  This study shows that the prevalence of ESBLs producing E. coli and K. pneumoniae is high in both study groups (out-patients and hospitalized patients). Therefore it seems that continuous surveillance is essential to monitor the ESBLs producing microorganisms in hospitals and community.
authors.affiliation: Microbiology and Virology Research Centre, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Fatemeh Riyahi
authors.initials: FR
authors.lastname: Zaniani
authors.forename: Zahra
authors.initials: Z
authors.lastname: Meshkat
authors.forename: Mahboubeh
authors.initials: M
authors.lastname: Naderi Nasab
authors.forename: Mehrangiz
authors.initials: M
authors.lastname: Khaje-Karamadini
authors.forename: Kiarash
authors.initials: K
authors.lastname: Ghazvini
authors.forename: Abdolrahim
authors.initials: A
authors.lastname: Rezaee
authors.forename: Habibollah
authors.initials: H
authors.lastname: Esmaily
authors.forename: Maryam Sadat
authors.initials: MS
authors.lastname: Nabavinia
authors.forename: Mahboubeh
authors.initials: M
authors.lastname: Darban Hoseini
keywords: Escherichia coli; Extended spectrum beta-lactamase (ESBL); Klebsiella pneumonia; PCR; Prevalence; SHV gene; TEM gene