Clinical manifestations and prognostic factors in cancer patients with bacteremia due to extended-spectrum β-lactamase-producing Escherichia coli or Klebsiella pneumoniae

Background: Clinical information about bacteremia due to extended-spectrum β-lactamase (ESBL)-producing pathogens in cancer patients was limited. The study was aimed to identify the clinical manifestations and risk factors for mortality in ESBL-producer bacteremia in cancer patients. Methods: A retrospective study of bacteremia caused by ESBL-producing Escherichia coli or Klebsiella pneumoniae in adults with cancer in National Cheng Kung University Hospital and National Taiwan University Hospital from July 2002 to August 2007 was conducted. Clinical characteristics, initial manifestations, and antimicrobial therapy were analyzed for their association with crude mortality at 14 days after bacteremia onset. Results: A total 113 episodes of bacteremia caused by E coli (59.3%), K pneumoniae (39.8%) or both (0.9%) were included. Patients with hematological malignancy were younger (55 ± 22 vs. 69 ± 14 years, p< 0.003) and had less co-morbidity, but were more likely to have neutropenia (73.1% vs. 4.6%, p< 0.001) than those with solid tumor. By the univariate analysis in 113 episodes of ESBL-producer bacteremia, several risk factors, including pneumonia or soft-tissue infection as the bacteremia source, initial manifestations with high Pitt bacteremia scores, shock, respiratory failure or severe sepsis, and inappropriate definitive therapy were associated with 14-day crude mortality. By multivariate analysis, only pneumonia [adjusted odds ratio (AOR), 5.2; 95% confident interval (CI), 1.3-21.0; p = 0.021], severe sepsis (AOR, 24.3; 95% CI, 5.6-105.0; p< 0.001), and inappropriate definitive therapy (AOR, 11.3; 95% CI, 1.7-72.8; p = 0.011) were independently associated with a fatal outcome. Conclusion: The presence of neutropenia or underlying hematological malignancy in cancer patients with ESBL-producer bacteremia was not associated with an increase in the mortality rate. Appropriate definitive antimicrobial therapy will be beneficial in improving clinical outcome.