Extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae bacteremia in febrile neutropenic children.

This retrospective study was conducted to evaluate clinical outcomes of bacteremia caused by extended-spectrum β-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae and their antibiotic susceptibilities in febrile neutropenic children. Clinical characteristics, prognosis, and antibiotic susceptibilities were reviewed and compared between febrile neutropenic children with bacteremia caused by ESBL-producing and non-ESBL-producing E. coli and K. pneumoniae. A total of 61 episodes of E. coli and K. pneumoniae bacteremia, including 21 episodes (34.4%) due to ESBL-producing strains, were diagnosed. There was no significant factor associated with bacteremia by ESBL-producing strains. Empirical antibiotics were appropriate in 85.7% of the ESBL group and 95.0% of the non-ESBL group. In the entire study population, seven deaths (11.5%), including three deaths (4.9%) due to E. coli and K. pneumoniae bacteremia, occurred. The complication and mortality rates were not significantly different between the two groups. Antibiotic susceptibility rates were significantly lower in the ESBL group than in the non-ESBL group in most antibiotics. Although 52.4% and 66.7% of the ESBL-producing isolates were susceptible to piperacillin/tazobactam and cefepime, respectively, 96.7% of all the isolates and 90.5% of the ESBL-producing isolates were susceptible to piperacillin/tazobactam or cefepime in combination with aminoglycoside. In conclusion, the ESBL group did not show a significantly unfavorable outcome, and empirical therapy with piperacillin/tazobactam or cefepime in combination with aminoglycoside might be more useful for febrile neutropenic children, instead of β-lactam monotherapy in institutions with high prevalence of ESBL-producing E. coli and K. pneumoniae.