African Journal of
Microbiology Research

  • Abbreviation: Afr. J. Microbiol. Res.
  • Language: English
  • ISSN: 1996-0808
  • DOI: 10.5897/AJMR
  • Start Year: 2007
  • Published Articles: 5233

Full Length Research Paper

Prevalence of extended spectrum beta lactamases (ESBL) in clinical isolates from a teaching hospital in Peshawar, Pakistan

Shahina Mumtaz1, Jawad Ahmed2*, Liaqat Ali1 and Hamid Hussain3
1Department of Pathology, Khyber Medical College, Peshawar, Khyber Pakhtunkhwa, Pakistan. 2Institute of Basic Medical Sciences, Khyber Medical University, Peshawar, Pakistan. 3Department of Community Medicine and Public Health, Khyber Medical College, Peshawar, Khyber Pakhtunkhwa, Pakistan.
Email: [email protected]

  •  Accepted: 22 August 2011
  •  Published: 23 September 2011


Infections caused by ESBL producing members of the enterobacteriaceae have rapidly increased all over the world. ESBL increase the possibility of failure of empiric antimicrobial regimens. The aim of this study was to determine the prevalence of ESBL in bacterial isolates and to look into the options for treating infections caused by these organisms. A total of 4,150 isolates of enterobacteriaceae were studied. ESBL producer isolates were 371 (8.94%) out of which 281 (75.7%) were recovered from admitted patients while 90 (24.3%) were recovered from outdoor patients. ESBL detection was carried out according to Clinical Laboratory and Standard Institute (CLSI) criteria. Majority of the ESBL producing isolates were obtained from urine 282 (76.0%), followed by swabs 69 (18.6%) fluids 12 (3.2%) blood 06 (1.7%) and sputum 02 (0.5%). The ESBL phenotype was detected in 322 (89.5%) of the isolates of E. coli, 20 (5.4%) of Klebsiella spp. 14 (3.8%) Enterobacter and 05 (1.3%) Citrobacter spp. Carbapenems was the drug of choice for serious infection with ESBL – producing organisms in Peshawar. These should not be administered as empiric therapy, because their over use can result in significant resistance in future.


Key words: Extended spectrum beta lactamases (ESBL), cephalosporins, Escherichia coli, phenotype screening.