Nosocomial multi-drug resistant Acinetobacter baumannii bloodstream infection: risk factors and outcome with ampicillin-sulbactam treatment

J Hosp Infect. 2003 May;54(1):32-8. doi: 10.1016/s0195-6701(03)00046-x.


The emergence of multidrug-resistant (MDR) Acinetobacter baumannii poses a therapeutic problem. The aim of this study was to assess the risk factors for nosocomial MDR-A. baumannii bloodstream infection (BSI) and the efficacy of ampicillin-sulbactam (A/S) in its treatment. Of 94 nosocomial A. baumannii BSI during the year 2000, 54% involved MDR strains, 81% of which were genetically related. Various risk factors for MDR-A. baumannii were found, of which intensive-care unit admission and prior aminoglycoside therapy were independently associated with MDR-A. baumannii acquisition on multivariate analysis. Of MDR-A. baumannii BSI cases, 65% received A/S and 35% inadequate antibiotic therapy, whereas of 43 non-MDR cases, 86% were treated according to susceptibility and 14% inappropriately with antibiotics to which these organisms were resistant. Crude mortality was comparable in the adequately treated groups. Respective mortalities among patients treated adequately and inadequately were 41.4 and 91.7% (p<0.001). Among severely ill patients, A/S therapy significantly decreased the risk of death (P=0.02 OR=7.64). MDR-A. baumannii has become highly endemic in our institution. A/S appears to be one of the last effective and safe empirical resorts for treatment of MDR A. baumannii BSI.

MeSH terms

  • Acinetobacter Infections / drug therapy
  • Acinetobacter Infections / epidemiology*
  • Acinetobacter Infections / microbiology
  • Acinetobacter baumannii / drug effects*
  • Acinetobacter baumannii / genetics
  • Acinetobacter baumannii / pathogenicity
  • Aged
  • Ampicillin / pharmacology*
  • Ampicillin / therapeutic use
  • Cross Infection / epidemiology
  • Cross Infection / microbiology
  • DNA, Bacterial / analysis
  • Drug Resistance, Multiple, Bacterial*
  • Drug Therapy, Combination / pharmacology*
  • Drug Therapy, Combination / therapeutic use
  • Female
  • Hospital Bed Capacity, 500 and over
  • Humans
  • Intensive Care Units
  • Israel / epidemiology
  • Male
  • Medical Records
  • Microbial Sensitivity Tests
  • Middle Aged
  • Outcome Assessment, Health Care*
  • Polymerase Chain Reaction
  • Retrospective Studies
  • Risk Factors
  • Sulbactam / pharmacology*
  • Sulbactam / therapeutic use


  • DNA, Bacterial
  • sultamicillin
  • Ampicillin
  • Sulbactam