Cross-transmission of multidrug-resistant Acinetobacter baumannii clonal strains causing episodes of sepsis in a trauma intensive care unit.
OBJECTIVE
To investigate the mode of transmission of imipenem-resistant Acinetobacter baumannii strains causing episodes of sepsis.


METHODS
A 7-bed trauma intensive care unit (ICU) in an orthopedic hospital in Greece.


METHODS
During a 14-week period (from January 10 to April 16, 2006), clinical specimens, along with samples taken on a weekly basis from the ICU environment and from the hands of health care workers (HCWs), were prospectively tested for imipenem-resistant A. baumannii. Pulsed-field gel electrophoresis was used to study the genetic relatedness of the isolates recovered from these specimens and samples.


RESULTS
During the survey, imipenem-resistant A. baumannii was identified in 14 hospitalized patients, from whom 40 multidrug-resistant and imipenem-resistant A. baumanii isolates were recovered. These pathogens caused episodes of bacteremia and sepsis in all but one of the patients and contributed to the death of 3 patients. Samples for culture were obtained from the environment and from the hands of HCWs; 29 imipenem-resistant A. baumannii isolates were recovered from the environment, and 12 from HCWs. One predominant genotype and 2 less predominant genotypes were detected among the 81 imipenem-resistant A. baumannii isolates. All 3 of these genotypes were found among patients and HCWs and were recovered from environmental samples.


METHODS
Control measures consisted of the closure of the ICU and the transfer of the patients to other units. The ICU was disinfected, and adherence to proper hand hygiene protocol was reinforced. These same clonal isolates were not recovered from clinical or environmental samples during the month after the reopening of the ICU.


CONCLUSIONS
The extensive dissemination of imipenem-resistant A. baumannii clonal strains causing episodes of bacteremia and/or sepsis resulted from modes of transmission via multiple contaminated surfaces and objects and transiently colonized HCWs' hands. Closure of the ICU and its meticulous environmental decontamination led to the successful control of the outbreak.
Markogiannakis
Antonios
A
Department of Basic Sciences, School of Health Sciences, University of Athens, Greece.
Fildisis
George
G
Tsiplakou
Sofia
S
Ikonomidis
Alexandros
A
Koutsoukou
Alexandra
A
Pournaras
Spyros
S
Manolis
Evangelos N
EN
Baltopoulos
George
G
Tsakris
Athanassios
A
D000151:Acinetobacter Infections / Q000453:epidemiology / Q000382:microbiology / Q000517:prevention & control / Q000635:transmission*; D040981:Acinetobacter baumannii / Q000145:classification / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology / Q000517:prevention & control / Q000635:transmission*; D004196:Disease Outbreaks / Q000517:prevention & control*; D024901:Drug Resistance, Multiple, Bacterial; D004777:Environment; D006115:Greece / Q000453:epidemiology; D006225:Hand / Q000382:microbiology*; D006282:Health Personnel; D006801:Humans; D017053:Infection Control / Q000379:methods; D007362:Intensive Care Units; D008826:Microbial Sensitivity Tests; D018805:Sepsis / Q000453:epidemiology / Q000382:microbiology; D014947:Wounds and Injuries
D000900:Anti-Bacterial Agents