2675. Changing Epidemiology of Bloodstream Infection During Chemotherapy for Acute Leukemia: Impact of Prophylactic Fluoroquinolone Restriction and Carbapenem Saving Strategy

Abstract Background Fluoroquinolone prophylaxis has been widely used in high-risk neutropenic patients with hematological malignancies, which may reduce bloodstream infection (BSI) and mortality. However, concerns about antibiotic resistance also exist. The aim of this study was to assess the impact of new institutional strategy of restricting fluoroquinolone prophylaxis and saving carbapenem, applied since October 2016. Fluoroquinolone prophylaxis was adopted only in remission induction chemotherapy, and carbapenems were saved until other antibiotics prove no effectiveness Methods We retrospectively reviewed all consecutive intensive chemotherapy episodes for acute leukemia from April 2016 to March 2017 at the Catholic Hematology Hospital. In addition, antibiotics consumption was assessed by calculating defined daily doses (DDDs) per 100 bed-days. Results Among 420 admissions during the study period, 201 and 219 admissions were identified before (period 1) and after (period 2) the strategy modification. Baseline characteristics including types of leukemia, chemotherapy, severity and duration of neutropenia were not different between the two periods.Development of febrile neutropenia (83.6% vs. 84.0%, P = 0.487), BSI (46.3% vs. 52.5%, P = 0.291), and septic shock (4.0% vs. 6.4%, P = 0.268) were not significantly different. Polymicrobial BSI increased significantly (7.1% vs. 20.0%, p = 0.012) in period 2. Quinolone resistance (97.8% vs. 43.6%, P < 0.001) and extended-spectrum β-lactamase producers (50% vs. 29.1%, P = 0.032) among Enterobacteriaceae were significantly reduced. Carbapenem-resistant Enterobacteriaceae was not isolated in period 2. Vancomycin resistance among enterococci (66.7% vs. 15%, P = 0.006) decreased. Consumption of ciprofloxacin (37.2 vs. 13.8) and carbapenem (22.3 vs. 16.8) decreased, while piperacillin/tazobactam consumption increased (5.2 vs. 13.0). BSI-related death (1.0% vs. 0.9%) was not increased. Conclusion Fluoroquinolone prophylaxis restriction and carbapenem saving strategies resulted in significant reduction of resistant bacterial BSIs, without increase in febrile neutropenia, BSI, septic shock, and BSI-related death. Antibiotics stewardship program can be tried in neutropenic patients, which may improve the ultimate outcome. Disclosures All authors: No reported disclosures.