Vancomycin-Resistant Enterococcus Colonization and Bacteremia and Hematopoietic Stem Cell Transplantation Outcomes

Abstract

The association between pre-hematopoietic stem cell transplantation (HSCT) vancomycin-resistant Enterococcus (VRE) colonization, HSCT-associated VRE bacteremia, and HSCT mortality is disputed. We studied 161 consecutive patients with acute leukemia who underwent HSCT at our hospital between 2006 and 2014, of whom 109 also received leukemia induction/consolidation on our unit. All inpatients had weekly VRE stool surveillance. Pre-HSCT colonization was not associated with increases in HSCT mortality but did identify a subgroup of HSCT recipients with a higher risk for VRE bacteremia and possibly bacteremia from other organisms. The major risk factor for pre-HSCT colonization was the number of hospital inpatient days between initial admission for leukemia and HSCT. One-third of evaluable patients colonized before HSCT were VRE-culture negative on admission for HSCT; these patients had an increased risk for subsequent VRE stool surveillance positivity but not VRE bacteremia. Molecular typing of VRE isolates obtained before and after HSCT showed that VRE strains frequently change. Postengraftment VRE bacteremia was associated with a much higher mortality than pre-engraftment VRE bacteremia. Pre-engraftment bacteremia from any organism was associated with an alternative donor and resulted in an increase in hospital length of stay and cost. Mortality was similar for pre-engraftment VRE bacteremia and pre-engraftment bacteremia due to other organisms, but mortality associated with post-engraftment VRE bacteremia was higher and largely explained by associated severe graft-versus-host disease and relapsed leukemia. These data emphasize the importance of distinguishing between VRE colonization before HSCT and at HSCT, between pre-engraftment and postengraftment VRE bacteremia, and between VRE bacteremia and bacteremia from other organisms.

Timepoints of vancomycin‐resistant Enterococcus colonization predict outcomes of acute myeloid leukemia patients undergoing allogeneic hematopoietic cell transplantation

“…months (range 0.6-40.2). This is comparable to 31% (16/52) patients in the study of Ford et al16 Factors known to be associated with this aspect, such as age and length of hospital stay,23,26 were equally distributed between the different groups. Possible confounders concealing a possible difference in OS between never-colonized and previously colonized patients could have been the different years, in which the allo-HSCT was performed (median of never-colonized: 2011, previously colonized: 2008), the number of patients that received ATG for GvHD prophylaxis (median of nevercolonized: 53.3%, previously colonized: 79.8%) and the small number of previously colonized patients.…”

Impact of Empiric Treatment for Vancomycin-Resistant Enterococcus in Colonized Patients Early after Allogeneic Hematopoietic Stem Cell Transplantation

“…For VRE infections, the empiric administration of gram-positive agents, such as linezolid, daptomycin, quinupristin-dalfopristin, and tigecycline, in patients with known VRE colonization undergoing induction chemotherapy for acute leukemia or allo-HSCT has not been prospectively evaluated in clinical studies. It has been reasoned that the results of VRE surveillance can potentially guide antimicrobial therapy for fever and neutropenia; however, the benefit of empirically initiating VRE-active therapy while awaiting blood culture results must be carefully weighed against the potential harm from this approach [1,22]. The most recent iteration of the IDSA practice guideline for use of antimicrobial agents in high-risk febrile patients with neutropenia recommends considering the early use of VRE-active agents in areas of high endemicity [9].…”

Comparison of risk factors and outcomes of daptomycin‐susceptible and ‐nonsusceptible vancomycin‐resistant enterococcus faecium infections in liver transplant recipients; A reply to Lewis et al

“…Interestingly, like Lewis, we found no difference in DNSE vs DSE outcomes, although they were poor compared with the unaffected population. Enterococcal infection has been suggested to be a surrogate marker of comorbidity burden in the stem cell transplant population 10 ; it is possible this is also the case after liver transplantation.…”