Clinical outcomes of carbapenem-resistant Acinetobacter baumannii bloodstream infections: study of a 2-state monoclonal outbreak.
OBJECTIVE
To characterize the clinical outcomes of patients with bloodstream infection caused by carbapenem-resistant Acinetobacter baumannii during a 2-state monoclonal outbreak.


METHODS
Multicenter observational study. Setting. Four tertiary care hospitals and 1 long-term acute care hospital.


METHODS
A retrospective medical chart review was conducted for all consecutive patients during the period January 1, 2005, through April 30, 2006, for whom 1 or more blood cultures yielded carbapenem-resistant A. baumannii.


RESULTS
We identified 86 patients from the 16-month study period. Their mortality rate was 41%; of the 35 patients who died, one-third (13) had positive blood culture results for carbapenem-resistant A. baumannii at the time of death. Risk factors associated with mortality were intensive care unit stay, malignancy, and presence of fever and/or hypotension at the time blood sample for culture was obtained. Only 5 patients received adequate empirical antibiotic treatment, but the choice of treatment did not affect mortality. Fifty-seven patients (66.2%) had a single positive blood culture result for carbapenem-resistant A. baumannii; the only factor associated with a single positive blood culture result was the presence of decubitus ulcers. Interestingly, during the study period, a transition from single to multiple positive blood culture results was observed. Four patients, 3 of whom were in a burn intensive care unit, were bacteremic for more than 30 days (range, 36-86 days).


CONCLUSIONS
To our knowledge, this is the first time a study has described 2 patterns of bloodstream infection with A. baumannii: single versus multiple positive blood culture results, as well as a subset of patients with prolonged bacteremia.
Munoz-Price
L Silvia
LS
University of Miami, Miami, FL, USA. smunozprice@med.miami.edu
Zembower
Teresa
T
Penugonda
Sudhir
S
Schreckenberger
Paul
P
Lavin
Mary Alice
MA
Welbel
Sharon
S
Vais
Dana
D
Baig
Mirza
M
Mohapatra
Sunita
S
Quinn
John P
JP
Weinstein
Robert A
RA
D000151:Acinetobacter Infections / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology / Q000401:mortality; D040981:Acinetobacter baumannii / Q000187:drug effects* / Q000302:isolation & purification; D000368:Aged; D000900:Anti-Bacterial Agents / Q000494:pharmacology* / Q000627:therapeutic use; D016470:Bacteremia / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology / Q000401:mortality*; D001769:Blood / Q000382:microbiology; D015780:Carbapenems / Q000494:pharmacology* / Q000627:therapeutic use; D003428:Cross Infection / Q000188:drug therapy / Q000453:epidemiology / Q000401:mortality; D003470:Culture Media; D004196:Disease Outbreaks; D024881:Drug Resistance, Bacterial; D005260:Female; D006801:Humans; D007362:Intensive Care Units; D007902:Length of Stay; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged
D000900:Anti-Bacterial Agents; D015780:Carbapenems; D003470:Culture Media