Impact of antibacterial prophylaxis during reinduction chemotherapy for relapse/refractory acute myeloid leukemia.

PURPOSE: This study evaluated the impact of antibacterial prophylaxis with levofloxacin in relapsed/refractory acute myeloid leukemia (AML) patients.

METHODS: This was a retrospective, single-center, cohort study. Adult patients with relapsed/refractory AML admitted for reinduction chemotherapy between November 1, 2006 and June 15, 2015 were screened for inclusion. A protocol initiating levofloxacin prophylaxis was implemented on December 1, 2013. Patients receiving hypomethylating agents (decitabine/azacitidine) were not administered antibacterial prophylaxis and thus not included in this analysis. Patients receiving broad spectrum antibiotics on day 1 of reinduction chemotherapy or receiving another antibacterial agent for prophylaxis were also excluded. Ninety-seven patients were included in the control group (no prophylaxis), while 48 patients received levofloxacin prophylaxis. Patients in the prophylaxis group received levofloxacin 500 mg once daily on day 1 of chemotherapy and continued until neutrophil recovery (or hospital discharge or death).

RESULTS: There was a reduction in the rate of bacteremia in the prophylaxis group (37.5 %) compared to the control group (53.6 %, p = 0.0789), largely due to a reduction in gram-negative bacteremia (2.1 vs. 21.6 % respectively, p = 0.001). No difference was found between prophylaxis and the control groups in the incidence of neutropenic fever, incidence of multidrug resistance, length of hospital or ICU stay, or mortality.

CONCLUSIONS: Levofloxacin prophylaxis reduced the rate of infections overall in adult patients with relapsed/refractory AML, without increasing rates of multidrug-resistant organisms.