Bacteraemia due to extended-spectrum b-lactamase producing Enterobacteriaceae in a tertiary care hospital in Salford, UK: one-year retrospective study

Abstract number: 1733_445

Ambalkar S., Ryan K., Chadwick P.R., Subudhi C.P.K.

Objectives: Extended-spectrum b-lactamase (ESBL) producing strains of Enterobacteriaceae have caused major therapeutic problems worldwide since the majority of these are resistant to multiple antibiotics. This retrospective observational study was conducted to determine the prevalence, antibiotic susceptibility pattern and outcome of treatment of ESBL-producing Enterobacteriaceae isolated from blood culture over a one year period.

Methods: The laboratory database was used to identify patients who had positive blood cultures for Enterobacteriaceae during the period October 2004 to September 2005. Case notes and electronic patient records were reviewed to determine the outcome of episodes of bacteraemia in patients due to ESBL producers. Antibiotic susceptibility pattern of ESBL positive isolates were analysed to determine the prevalence of co-resistance to ciprofloxacin, gentamicin and piperacillin-tazobactam.

Results: There were 220 patients who had positive blood cultures for Enterobacteriaceae during this period. Approximately 10% (23/220) of these patients had ESBL-producing isolates. Bacteraemia due to ESBL-producing organisms in this study was healthcare-associated in all 23 patients (100%). 70% of these patients were aged more than 65 years. E. coli was the most common (70%) isolate amongst the ESBL-producing organisms. All the ESBL-producing isolates were susceptible to carbapenems. Resistance to ciprofloxacin, gentamicin and piperacillin-tazobactam was present in 80% (19/23), 55% (12/23) and 24% (5/23) of these isolates respectively. Majority (72%) of patients had inappropriate empirical antibiotic therapy with ceftriaxone. There was 48% (11/23) 30 day associated mortality amongst patients with bacteraemia due to ESBL-producing organisms.

Conclusions: ESBL-producing strains of Enterobacteriaceae are a significant cause of healthcare-associated blood stream infections. They carry a high risk of mortality. Empirical treatment of sepsis caused by Enterobacteriaceae needs to be reconsidered in areas where there is high prevalence of ESBL producers as there are therapeutic implications due to co-resistance to multiple antibiotics.

Session Details

Date: 31/03/2007
Time: 00:00-00:00
Session name: European Society of Clinical Microbiology and Infectious Diseases
Location: ICC, Munich, Germany
Presentation type:
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