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  • Poster presentation
  • Open Access

Impact of antibiotic utilization measures on acquisition rate of extended spectrum β-lactamase enzymes producing bacteria

  • 1,
  • 1,
  • 1 and
  • 2
Critical Care200711 (Suppl 2) :P106

  • Published:


  • Cephalosporin
  • Intervention Phase
  • Resistance Pattern
  • Acquisition Rate
  • Utilization Measure


Antibiotic resistance patterns are continually changing; a new problem has been the emergence of Gram-negative bacteria, primarily Escherichia coli and Klebsiellae pneumoniae, producing extended spectrum β-lactamase enzymes (ESBL). Antibiotic use measures are presumably the most important intervention in preventing their clonal outbreak, and the risk factors for ESBL include intensive antibiotic exposure (especially third-generation cephalosporin monotherapy). The present study was performed to determine the impact of using piperacillin/tazobactum in reducing the acquisition rate of ESBL producing Gram-negative bacteria in the ICU.


This open-label, prospective study was carried out in 140 adult patients admitted to the ICU over a period of 9 months, and was divided into two phases. Phase I (pre-intervention phase, 0–3 months): upon admission to the ICU, besides standard investigations, additional rectal swab cultures were taken for detection of ESBL within and after 48 hours of admission, and were repeated every 7 days of the stay in the ICU. Routinely prescribed antibiotics were allowed. Phase II (intervention phase, 4–9 months): this was subdivided into (a) first 3 months (4–6 months): piperacillin/tazobactum was the primary antibiotic used (more than 50% replacement of cephalosporins), and (b) last 3 months (7–9 months): here again, rectal swab cultures were taken and piperacillin/tazobactum was the primary antibiotic used. McNemar's test and Fisher's exact test were used for statistical analysis.


Eighty-five patients in phase I and 55 patients in phase II were enrolled. Third-generation cephalosporins were the primary antibiotic in 75.2% of cases in phase I and in 1.8% of cases in phase II (P < 0.001). The incidence of ESBL was 62.3% in phase I and it came down to 34.5% in intervention phase II (P < 0.01).


Data from this intervention study support the concept that third-generation cephalosporins are of substantial importance in the emergence of ESBL; by decreasing the level of third-generation cephalosporin use and increasing the piperacillin/tazobactum use, their was a notable reduction in the acquisition rate of ESBL producing E. coli.

Authors’ Affiliations

Kailash Hospital, Noida, India
Wyeth, Bombay, India


© BioMed Central Ltd. 2007