• Shamim Mumtaz
  • Mumtaz Ahmad
  • Irum Aftab
  • Naeem Akhtar
  • Masood ul Hassan
  • Abdul Hamid


Background: Extended Spectrum β-Lactamases (ESBLs)-producing strains of Enterobacteriaceaehave emerged as a major problem in hospitalized as well as community based patients. Infectionsdue to ESBLs-producers range from uncomplicated urinary tract infection to life threatening sepsis.The objective of this study was to find out the prevalence of ESBLs-producing Gram- negativebacilli among clinical isolates. Methods: This descriptive study was conducted at the Microbiologydepartment of Fauji Foundation Hospital, Rawalpindi over a period of two years (March 2004–April2006). Six hundred and nine isolates of Enteric Gram-negative rods from various samples weretested for ESBLs- production by double disc synergy test. In 176 ESBLs-producing isolates, sourceof samples in term of indoor/outdoor was analyzed. In 165 ESBLs-producing isolates, patients’gender and age was analysed from 3 months to 70 years. Results: The ESBLs-producing isolateswere more commonly isolated from indoor patients (88.1%) as compared to outdoor patients(11.9%). Escherichia coli was found to be most prevalent organism in indoor patients whileKlebsiella pneumoniae, was the most prevalent organism in outdoor patients. ESBLs were mostcommonly isolated from female patients (64.3%) suffering from urinary tract infections ((41.5%), ascompared to male patients (35.7%) in which the organisms were most commonly isolated from pussamples (54.2 %). ESBLs-producing Enteric Gram-Negative rods were most frequent at later part oflife where they were most common (27.9%) at 61–70 years, followed by 41–50 years of age group(20.0%). Another peak (13.3%) was also seen at younger age group (11–20 years). The leastprevalence (5.5%) was seen in two age groups (0–10 and 31–40 yrs). In case of female patients,ESBLs-producing EGNR were most frequently (29.2%) isolated from middle age group (41–50years) followed by later age groups (51–60 and 61–70 years, (15.1% and 25.5%). Conclusions:Considering the high prevalence of ESBLs in Enteric Gram-negative rods, it is suggested that allsuch isolates should be tested for the production of ESBLs in the routine microbiology laboratory.Key Words: Extended-Spectrum Beta-lactamases, Enterobacteriaceae, Enteric Gram-Negativerods, Escherichia coli, Klebsiella pneumoniae, Enterobacter spp


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