FLUOROQUINOLONE PROPHYLAXIS FOR FEBRILE NEUTROPENIA IN AUTOLOGOUS HEMATOPOIETIC CELL TRANSPLANTATION: OUTCOMES AND RISK FACTORS

Febrile neutropenia (FN) is a complication after autologous hematopoietic cell transplantation (auto-HCT). Although fluoroquinolone (FQ) prophylaxis can reduce FN rates, its use remains debated due to concerns about antimicrobial resistance. We retrospectively analyzed adult patients who underwent auto-HCT at A.C.Camargo Cancer Center between 2016 and 2021. Patients were grouped by FQ prophylaxis: those who received levofloxacin from 2016-2018 (Px group, n = 201) and those who did not from 2018-2021 (NPx group, n = 169). FN was more frequent in the NPx group (92%) than in the Px group (81%) (p = 0.002). However, no significant differences were found in microbiologically documented infections (23% vs. 14%, p = 0.09), 30-day mortality (3% vs. 1%, p = 0.25), or 100-day mortality (3% vs. 2%, p = 0.48). Resistance profiles differed: the Px group had fewer pan-susceptible isolates (17% vs. 61%) and higher rates of ESBL-producing organisms (27% vs. 6%) and methicillin-resistant bacteria (36% vs. 10%) (all p < 0.001). These findings indicate that although FQ prophylaxis reduces FN incidence, it does not affect short-term mortality and is associated with greater antimicrobial resistance. Based on these results, our institution does not recommend use of FQ prophylaxis in patients undergoing auto-HCT.