Bacteremia due to extended-spectrum beta-lactamase-producing Enterobacteriaceae other than Escherichia coli and Klebsiella.

BACKGROUND AND PURPOSE

Carbapenems are considered the drugs of choice for the treatment of serious infections caused by extended-spectrum beta-lactamase (ESBL)-producing Klebsiella and Escherichia coli. However, controversy exists about the antibiotic choice for infections due to ESBL-producing organisms of other genera.

METHODS

This retrospective study evaluated the risk factors and outcomes of 54 adult patients with bacteremia due to ESBL-producing Enterobacteriaceae other than Klebsiella spp. or E. coli treated at a tertiary care hospital in northern Taiwan from January 2001-December 2003. Patients were categorized into carbapenem (n = 22) and non-carbapenem (n = 32) treatment groups. All patients had at least one positive blood culture together with fever or other clinical features compatible with systemic infection.

RESULTS

Higher Acute Physiology and Chronic Health Evaluation II score, glucocorticoid use, and presentation of septic shock were significant risk factors for mortality (p<0.05). Patients treated with a carbapenem had a better 14-day or overall survival rate (i.e., survived to discharge) than those treated with non-carbapenem antibiotics, although this difference was not significant. Among patients in the non-carbapenem group, the overall survival rates of ciprofloxacin, aminoglycoside, and ceftazidime were 70% (14/20), 62.5% (5/8), and 50% (2/4), respectively (p=0.877). The overall survival rates of the carbapenem (72.7%) and ciprofloxacin (70.0%) groups were similar.

CONCLUSIONS

The results suggest that ciprofloxacin, when indicated based on antimicrobial susceptibility testing, may serve as an alternative choice for infections caused by ESBL-producing Enterobacteriaceae other than E. coli or Klebsiella spp. and may not affect the clinical outcome at discharge.