Nosocomial Acinetobacter baumannii vs. Klebsiella pneumoniae bloodstream infections: risk factors and outcomes

Abstract number: p1367

Paul  M., Robenstock  E., Fraser  A., Leibovici  L., Perez  S., Pitlik  S., Ostfeld  I., Samra  Z., Weinberger  M.


To assess mortality associated with nosocomial Acinetobacter baumannii (AB), bloodstream infections (BSIs), independent of other risk factors for mortality. We compared risk factors and outcomes for patients with nosocomial AB vs. nosocomial Klebsiella pneumoniae (KP) BSIs.


The study was conducted at Rabin Medical Center, Beilinson campus, a 900-bed primary and tertiary care hospital in Israel. All patients with nosocomial AB and KP BSIs between 2000–2003 were identified from an ongoing prospective database. Only first episodes were included. Detailed demographic, microbiologic, antibiotic treatment and other clinical data were collected retrospectively through patient chart review, using a standardized questionnaire. Nosocomial BSIs were defined as those developing more than 48 hours after admission. Mortality was defined as 30-day all-cause deaths. Variables significantly associated with mortality at the univariate level (p < 0.1) were entered into a multivariable logistic regression model.


112 patients with AB and 90 patients with KP nosocomial BSIs were included. AB was significantly associated with poorer performance status; burns; pneumonia, mechanical ventilation, arterial line and nasogastric tube prior to BSI; prior treatment with steroids and carbapenems, but not other antibiotics; pneumonia as source of infection; lower albumin and higher urea. KP BSIs were associated with urinary tract infections. Appropriate empirical antibiotic treatment was administered to 19.6% of patients with AB and 42.2% of patients with KP BSI (p < 0.001). AB BSIs were associated with a significantly higher percentage of septic shock and respiratory failure and resulted in longer hospital stay (32 ± 27 days vs. 22 ± 20 days for patients alive). Mortality was 61.6% with AB vs. 38.9% with KP (p < 0.001). Independent risk factors for mortality on multivariate analysis included AB BSI, diabetes, septic shock and urea (Table).


AB affects patients with more severe underlying conditions in hospital, when compared to a common nosocomial Gram-negative pathogen. However, the mortality associated with AB BSIs is higher than that of KP BSIs, after correction for underlying patients' conditions.

Session Details

Date: 01/08/2007
Time: 00:00-00:00
Session name: XXIst ISTH Congress
Location: Oxford, UK
Presentation type:
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