Risk factors for vancomycin-resistant enterococcus bacteremia and its influence on survival after allogeneic hematopoietic cell transplantation.

Vancomycin-resistant enterococcus (VRE) is a well-known infectious complication among immunocompromised patients. We performed a retrospective analysis to identify risk factors for the development of VRE bacteremia (VRE-B) within 15 months after allogeneic hematopoietic cell transplantation (alloHCT) and to determine its prognostic importance for other post-transplant outcomes. Eight hundred consecutive adult patients who underwent alloHCT for hematologic diseases from 1997 to 2011 were included. Seventy-six (10%) developed VRE-B at a median of 46 days post transplant. Year of transplant, higher HCT comorbidity score, a diagnosis of ALL, unrelated donor and umbilical cord blood donor were all significant risk factors on multivariable analysis for the development of VRE-B. Sixty-seven (88%) died within a median of 1.1 months after VRE-B, but only four (6%) of these deaths were attributable to VRE. VRE-B was significantly associated with worse OS (hazard ratio 4.28, 95% confidence interval 3.23-5.66, P<0.001) in multivariable analysis. We conclude that the incidence of VRE-B after alloHCT has increased over time and is highly associated with mortality, although not usually attributable to VRE infection. Rather than being the cause, this may be a marker for a complicated post-transplant course. Strategies to further enhance immune reconstitution post transplant and strict adherence to infection prevention measures are warranted.

Intravenous compared with oral busulfan as preparation for allogeneic hematopoietic progenitor cell transplantation for AML and MDS.

BU and CY is a common conditioning regimen for allogeneic hematopoietic progenitor cell transplantation (HPCT). I.v. BU is increasingly used in place of the oral formulation for conditioning. We compared the outcomes of 135 consecutively treated AML and myelodysplastic syndrome patients who underwent allogeneic HPCT at our institution with BUCY2 using oral (n=93) or i.v. (n=42) BU, without dose adjustment. The i.v. BU patients had a lower incidence of any severity of oral mucositis (3 versus 55%, P=0.002) and severe mucositis (3 versus 24%, P=0.005). Other post transplant outcomes were comparable between the groups. In all 26 i.v. BU and 33 oral BU patients are alive; however, the median follow-up was significantly longer for the oral BU group. One- and two-year non-relapse mortality for the i.v. BU patients was 21% for both, and for the oral BU group was 23% and 29%, respectively. One- and two-year relapse mortality for the i.v. BU patients was 21% for both, and for the oral BU group was 24% and 29%, respectively. Substituting i.v. for oral BU reduces variability in drug exposure and potentially improves toxicity as suggested by our finding of significantly less oral mucositis and decreased severity with i.v. BU.