title: ESBL-producing Escherichia coli and Klebsiella pneumoniae at a tertiary care hospital in Saudi Arabia.
abstract: BACKGROUND
  The increasing frequency and antibiotic resistance among extended-spectrum β-lactamases (ESBLs)-producing bacteria are posing a serious threat. This study sought to investigate the frequency and antibiotic susceptibility of ESBL-producing E. coli and K. pneumoniae at a tertiary care hospital.
  
  
  METHODS
  Data were collected from samples sent to the microbiology laboratory between 2006 and 2010 at King Khalid University Hospital, Riyadh. ESBLs were confirmed using Etest strips of cefotaxime/cefotaxime + clavulanic acid, ceftazidime/ceftazidime + clavulanic acid, and cefepime/cefepime + clavulanate.
  
  
  RESULTS
  Out of 17,105 samples, 1,076 (6.3%) ESBL-producing isolates of E. coli (808) and K. pneumoniae (268) were confirmed. Among these, 680 (63.2%) isolates were found in urine samples, followed by 287 (26.7%) in superficial swabs, deep wounds swabs, tissues and sterile body fluids, 71 (6.6%) in respiratory, and 38 (3.5%) in blood samples. The overall frequency rates of ESBL E. coli and K. pneumoniae were 6.6% and 5.5%, respectively. The frequency of ESBL-producing E. coli and K. pneumoniae increased significantly during the study period. E. coli resistance against cotrimoxazole was 71.1%, followed by ciprofloxacin (68.2%) and gentamicin (47%). Similarly, 62.7% of K. pneumoniae isolates were resistant to gentamicin, 59.5% to cotrimoxazole, and 49.8% to ciprofloxacin. There was no statistically significant change in antimicrobial resistance over the study period.
  
  
  CONCLUSIONS
  Although the frequency rates of ESBL-producing E. coli and K. pneumoniae increased, no change in the anti-microbial susceptibility was observed over the study period.
authors.affiliation: King Saud University Hospital, Riyadh, Saudi Arabia. ali.somily@gmail.com.
authors.forename: Ali Mohammed
authors.initials: AM
authors.lastname: Somily
authors.forename: Hanan A
authors.initials: HA
authors.lastname: Habib
authors.forename: Muhammad M
authors.initials: MM
authors.lastname: Absar
authors.forename: Muhammad Z
authors.initials: MZ
authors.lastname: Arshad
authors.forename: Kutubu
authors.initials: K
authors.lastname: Manneh
authors.forename: Sarah S
authors.initials: SS
authors.lastname: Al Subaie
authors.forename: Mogbil A
authors.initials: MA
authors.lastname: Al Hedaithy
authors.forename: Samina B
authors.initials: SB
authors.lastname: Sayyed
authors.forename: Zahid
authors.initials: Z
authors.lastname: Shakoor
authors.forename: Thomas S
authors.initials: TS
authors.lastname: Murray
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002648:Child; D002675:Child, Preschool; D004926:Escherichia coli / Q000201:enzymology* / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000382:microbiology*; D005260:Female; D006801:Humans; D007223:Infant; D007710:Klebsiella Infections / Q000382:microbiology*; D007711:Klebsiella pneumoniae / Q000201:enzymology* / Q000302:isolation & purification; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D011446:Prospective Studies; D012529:Saudi Arabia; D062606:Tertiary Care Centers; D055815:Young Adult; D001618:beta-Lactamases / Q000032:analysis*; D047090:beta-Lactams / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D047090:beta-Lactams; D001618:beta-Lactamases