Multi-drug resistant Acinetobacter infections in critically injured Canadian forces soldiers.
BACKGROUND
Military members, injured in Afghanistan or Iraq, have returned home with multi-drug resistant Acinetobacter baumannii infections. The source of these infections is unknown.


METHODS
Retrospective study of all Canadian soldiers who were injured in Afghanistan and who required mechanical ventilation from January 1 2006 to September 1 2006. Patients who developed A. baumannii ventilator associated pneumonia (VAP) were identified. All A. baumannii isolates were retrieved for study patients and compared with A. baumannii isolates from environmental sources from the Kandahar military hospital using pulsed-field gel electrophoresis (PFGE).


RESULTS
During the study period, six Canadian Forces (CF) soldiers were injured in Afghanistan, required mechanical ventilation and were repatriated to Canadian hospitals. Four of these patients developed A. baumannii VAP. A. baumannii was also isolated from one environmental source in Kandahar - a ventilator air intake filter. Patient isolates were genetically indistinguishable from each other and from the isolates cultured from the ventilator filter. These isolates were resistant to numerous classes of antimicrobials including the carbapenems.


CONCLUSIONS
These results suggest that the source of A. baumannii infection for these four patients was an environmental source in the military field hospital in Kandahar. A causal linkage, however, was not established with the ventilator. This study suggests that infection control efforts and further research should be focused on the military field hospital environment to prevent further multi-drug resistant A. baumannii infections in injured soldiers.
Tien
Homer C
HC
The Trauma Program, and Department of Surgery, Sunnybrook Health Sciences Centre, H186-2075 Bayview Avenue, Toronto, Canada, M4N 3M5. homer.tien@sunnybrook.ca
Battad
Anthony
A
Bryce
Elizabeth A
EA
Fuller
Jeffrey
J
Mulvey
Michael
M
Bernard
Kathy
K
Brisebois
Ronald
R
Doucet
Jay J
JJ
Rizoli
Sandro B
SB
Fowler
Robert
R
Simor
Andrew
A
D000151:Acinetobacter Infections / Q000453:epidemiology* / Q000382:microbiology; D040981:Acinetobacter baumannii / Q000145:classification* / Q000187:drug effects / Q000235:genetics; D000328:Adult; D000346:Afghanistan / Q000453:epidemiology; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D015373:Bacterial Typing Techniques; D004269:DNA, Bacterial / Q000235:genetics; D024901:Drug Resistance, Multiple, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D006772:Hospitals, Military; D006801:Humans; D008851:Micropore Filters / Q000382:microbiology; D008889:Military Personnel; D053717:Pneumonia, Ventilator-Associated / Q000453:epidemiology* / Q000382:microbiology; D012189:Retrospective Studies; D012307:Risk Factors; D012122:Ventilators, Mechanical / Q000382:microbiology; D014947:Wounds and Injuries / Q000150:complications
D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial
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