Fluoroquinolone Prophylaxis For The Prevention Of Central Line-Associated Bloodstream Infection In Autologous Stem Cell Transplant.

e19508 Background: Patients (Pts) undergoing stem cell transplant (SCT) for the treatment of hematologic malignancy are at increased risk for central line-associated bloodstream infection (CLABSI). Use of prophylactic antibiotics to prevent CLABSI in autologous SCT (autoSCT) is of unclear benefit. We aimed to evaluate the impact of levofloxacin prophylaxis on reducing CLABSI in autoSCT. Methods: Pts undergoing autoSCT at the University of Pennsylvania received levofloxacin prophylaxis during a 6-month intervention period from 1/13/2016 - 7/12/2016. Levofloxacin was administered from autoSCT until day 13, absolute neutrophil count > 500/mm 3 , or febrile neutropenia. Outcomes were compared to a retrospective cohort who underwent autoSCT, but did not receive routine antibacterial prophylaxis during the previous year (1/13/2015 – 1/12/2016). The primary endpoint was incidence of CLABSI assessed using Cox proportional hazards regression. Results: A total of 243 pts underwent autoSCT, with 69 receiving levofloxacin prophylaxis during the intervention period. Median age was 59 yrs, 74% had multiple myeloma, and 58% received melphalan 200mg/m 2 . Median duration of neutropenia was 6 days. CLABSI rate was reduced from 18.4% during the baseline period to 7.3% during the intervention period ( P= 0.03). There were no significant differences in characteristics between the baseline and intervention groups except for liver disease (1% versus 5%, P= 0.03). On multivariable analysis, levofloxacin prophylaxis was associated with a significant reduction in CLABSI incidence (HR 0.33; 95% CI 0.12-0.88; P= 0.02), as was underlying multiple myeloma (HR 0.38; 95% CI 0.20-0.74; P= 0.004) and liver disease (HR 4.31; 95% CI 0.99-18.8; P= 0.05). There was also a reduction in neutropenic (NTP) fever (OR 0.21; 95% CI 0.11-0.38; P< 0.001) and a trend toward reduction in ICU transfer for sepsis (OR 0.13; 95% CI 0.01-1.39; P= 0.08) in patients receiving levofloxacin prophylaxis. There were no significant differences in rates of secondary BSIs, C. difficileinfection, or mortality. Conclusions: Levofloxacin prophylaxis was effective in reducing CLABSI and NTP fever in patients undergoing autoSCT.