Enterococcal bacteremia is associated with increased risk of mortality in recipients of allogeneic hematopoietic stem cell transplantation.
BACKGROUND
Enterococci are an important cause of healthcare-associated infections. We retrospectively analyzed risk factors and outcome of vancomycin-resistant enterococci (VRE) and vancomycin-sensitive enterococci (VSE) infections.


METHODS
Seven hundred fifty-two patients who received hematopoietic stem cell transplants from 2004 through 2008 at the University of Minnesota were included.


RESULTS
Ninety-three patients had enterococcal bloodstream infection (BSI) during the first year after transplant. Vancomycin resistance was observed in 66% and 31% of isolates in adults and children, respectively. Cumulative incidence of VRE and VSE bacteremia was 6.6% (95% confidence interval [CI], 4.8%-8.4%) and 5.7% (95% CI, 4.0%-7.4%), respectively. Colonization with VRE before or after transplant was a risk factor for VRE bacteremia (odds ratio [OR], 3.3 [95% CI, 1.3-8.3] and 7.0 [95% CI, 4.0-14.8], respectively). Delay in engraftment increased the incidence of VRE bacteremia from 4.5% (95% CI, 2.9-6.6) if engrafted before day 21 and to 15% (95% CI, 3.2%-38%) if engrafted between days 36 and 42. In adults, mortality 30 days after infection was 38% for both VRE (95% CI, 25%-54%) and VSE cases (95% CI, 21%-62%). The hazard ratio for all-cause mortality up to 1 year after transplant was 4.2 (95% CI, 3.1-6.9) and 2.7 (95% CI, 1.4-5.1) for patients with VRE and VSE BSIs, respectively, compared to patients without enterococcal BSI. In pediatric patients, mortality 30 days after VRE and VSE bacteremia was 20% (95% CI, 5.4%-59%) and 4.5% (95% CI, .6%-28%), respectively.


CONCLUSIONS
High rates of vancomycin resistance and association of enterococcal infections with significant mortality warrant further efforts to optimize prevention and management of these infections.
Division of Hematology-Oncology and Transplantation, Department of Medicine, Masonic Cancer Center, Minneapolis, Minnesota, USA.
Jan
J
Vydra
Ryan M
RM
Shanley
Ige
I
George
Celalettin
C
Ustun
Angela R
AR
Smith
Daniel J
DJ
Weisdorf
Jo-Anne H
JA
Young
D000293:Adolescent; D000328:Adult; D000368:Aged; D016470:Bacteremia / Q000453:epidemiology* / Q000382:microbiology / Q000401:mortality*; D002648:Child; D002675:Child, Preschool; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology / Q000401:mortality; D016983:Enterococcus / Q000302:isolation & purification*; D005260:Female; D016908:Gram-Positive Bacterial Infections / Q000453:epidemiology* / Q000382:microbiology / Q000401:mortality*; D018380:Hematopoietic Stem Cell Transplantation / Q000009:adverse effects*; D006785:Hospitals, University; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D008910:Minnesota / Q000453:epidemiology; D012189:Retrospective Studies; D012307:Risk Factors; D016019:Survival Analysis; D014184:Transplantation, Homologous / Q000009:adverse effects*; D016896:Treatment Outcome; D020713:Vancomycin Resistance; D055815:Young Adult