Defining Incidence and Risk Factors for Catheter-Associated Bloodstream Infections in an Outpatient Adult Hematopoietic Cell Transplantation Program.

Allogeneic hematopoietic cell transplantation (HCT) patients are at an increased risk of developing central line-associated bloodstream infections (CLABSIs) due to prolonged periods of myelosuppression, immunosuppression, and indwelling catheter days. CLABSIs are among the most serious complications in HCT recipients and can lead to prolonged hospitalizations, intensive care unit admissions, lengthy antimicrobial therapies, and increased mortality. There is a lack of data regarding the incidence and risk factors associated with the development of CLABSIs in the HCT population undergoing outpatient transplantation. This was a single-center, retrospective analysis of adult patients who underwent allogeneic HCT between July 2012 and July 2016 in an outpatient transplant unit at a tertiary academic medical center. The primary outcome was the cumulative incidence of CLABSIs from the date of central line placement through the first 100 days post-transplantation. Secondary outcomes included risk factors for CLABSI, number of hospitalizations due to CLABSI, mortality rate at 6 months post-transplantation, and the cumulative incidence, speciation, and presence of multidrug resistance in identified microorganisms. Three hundred fifty-nine patients underwent allogeneic HCT at Vanderbilt University Medical Center and 352 were included for analysis. The cumulative incidence of CLABSIs was 9%, with the majority occurring within the first 30 days post HCT (67%). The use of a matched unrelated donor (MUD) and/or haploidentical donor (odds ratio, 3.993; 95% confidence interval [CI], 1.329 to 12.001; P = .0136) and use of an ablative conditioning regimen (odds ratio, 2.394; 95% CI, 1.052 to 5.446; P = .0374) were independently associated with development of a CLABSI on multivariate analysis. The most common organism implicated in CLABSI was Staphylococcus epidermidis (34%). Patients who developed a CLABSI had an almost 5 times higher risk of mortality at 6 months post-transplantation compared with patients who did not develop a CLABSI (hazard ratio, 4.932; 95% CI, 2.463 to 9.878; P < .001). There is a low incidence of CLABSIs in patients undergoing HCT in the outpatient setting. Patients who underwent HCT using a MUD or haploidentical donor and received ablative conditioning were at higher risk for developing CLABSIs. Overall mortality at 6 months post-transplantation was higher in patients who developed a CLABSI. Additional prospective studies are needed to confirm these observations.