1. ¹Division of Geographic Medicine and Infectious Diseases, Department of Medicine, Tufts-New England Medical Center, Boston, MA, USA
2. ²Division of Clinical Care Research, Department of Medicine, Tufts-New England Medical Center, Boston, MA, USA
3. ³Tufts University School of Medicine, Boston, MA, USA
4. ⁴Division of Hematology and Oncology, Department of Medicine, Tufts-New England Medical Center, Boston, MA, USA

Correspondence: Dr DD Poutsiaka, Division of Geographic Medicine and Infectious Diseases, Tufts-New England Medical Center, 750 Washington Street, Box 041, Boston, MA 02111, USA. E-mail: dpoutsiaka@tufts-nemc.org

Received 23 October 2006; Revised 15 March 2007; Accepted 26 March 2007; Published online 30 April 2007.

Abstract

Blood stream infection (BSI) is a serious complication of hematopoietic stem cell transplantation (HSCT). The aim of this retrospective cohort analysis was to describe BSI after HSCT, and to assess the predictors and outcomes of BSI after HSCT using multivariable modeling. Of the 243 subjects transplanted, 56% received allogeneic HSCT and 106 (43.6%) developed BSI. Of the 185 isolates, 68% were Gram-positive cocci, 21% were Gram-negative bacilli (GNR) and 11% were fungi. Type of allogeneic HSCT was an independent risk factor for BSI (hazard ratio (HR) 3.26, 95% confidence interval (CI) 1.50, 7.07, P=0.01), as was the degree of HLA matching (HR 1.84, 95% CI 1.00, 3.37, P=0.05). BSI was a significant independent predictor of mortality after HSCT (HR 1.79, 95% CI 1.18, 2.73, P=0.007), after adjusting for acute graft-versus-host disease (GVHD) and allogeneic HSCT (both predicting death 3 months after HSCT). In contrast to the effects of acute GVHD and allogeneic HSCT, the effect of BSI was evident throughout the post-HSCT period. GNR BSI and vancomycin-resistant enterococcal BSI also were significantly associated with death. We concluded that BSI is a common complication of HSCT associated with increased mortality throughout the post-HSCT period.