Blood stream infection after hematopoietic stem cell transplantation is associated with increased mortality

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 ¼ 0.01), as was the degree of HLA matching (HR 1.84, 95% CI 1.00, 3.37, P ¼ 0.05). BSI was a significant independent predictor of mortality after HSCT (HR 1.79, 95% CI 1.18, 2.73, P ¼ 0.007), after adjusting for acute graft-versus-host disease (GVHD) and allogeneic HSCT (both predicting death p3 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.

Etiology, clinical features and outcomes of pre-engraftment and post-engraftment bloodstream infection in hematopoietic SCT recipients

“…27 Gram-positive organisms, especially CNS, were the most frequent etiology of BSI in both periods, in agreement with other studies involving HSCT recipients. 3,5,10,28 The frequency of Gram negatives was similar in both groups, as was the rate of multidrug resistance among them. The overall rate of multidrug-resistant Gram-negative bacilli was 21%.…”

“…This finding is in line with other studies that have found a higher risk of BSI in this specific group of transplant recipients. 3,7 During the pre-engraftment period, we identified the presence of neutropenia, a central venous catheter and severe mucositis as important risk factors for BSI. During the pre-engraftment phase it is likely that mucosal damage allows bacteria to enter the bloodstream and the lack of neutrophils hampers their effective clearance, thus leading to BSI.…”

“…Neutropenia was defined as an absolute neutrophil count o 500/mm 3 . The criterion for engraftment was an absolute neutrophil count of 500/mm 3 or more for 3 consecutive days.…”

“…[1][2][3][4] BSI in HSCT recipients has mainly been described in the pre-engraftment period, when neutropenia and mucosal damage represent the most important predisposing factors for BSI; however, BSI may also occur post-engraftment, when it is associated with other risk factors. 2,3,5 The epidemiology, clinical characteristics and etiology of BSI in HSCT recipients may vary depending on the time since transplantation. Nevertheless, the differences between infections occurring pre-and post-engraftment have not been fully described.…”

“…Nevertheless, the differences between infections occurring pre-and post-engraftment have not been fully described. 2,6 Most published articles regarding BSI in HSCT recipients are retrospective and/or focus on subjects who underwent transplantation in the 1990 s. 3,[5][6][7][8][9][10] Since then, there have been changes in the care of HSCT recipients, such as the introduction of different types of donors, different immunosuppression, conditioning chemotherapy including reduced-intensity regimens, and so on. Furthermore, changes in the etiology of BSI in cancer patients have recently been described.…”