Carbapenem versus Cefepime or Piperacillin-Tazobactam for Empiric Treatment of Bacteremia Due to Extended-Spectrum-β-Lactamase-Producing in Patients with Hematologic Malignancy.

Infections with extended-spectrum-β-lactamase (ESBL)-producing are common in patients with hematologic malignancy. The utility of cefepime and piperacillin-tazobactam as empiric therapy for ESBL-producing bacteremia in patients with hematologic malignancy is largely unknown. We conducted a single-center, retrospective cohort review of 103 adult inpatients with leukemia and/or hematopoietic stem cell transplant (HCT) recipients with monomicrobial ESBL-producing bacteremia. No association between increased 14-day mortality and empiric treatment with cefepime (8%) or piperacillin-tazobactam (0%) relative to that with carbapenems (19%) was observed ( = 0.19 and  = 0.04, respectively). This observation was consistent in multivariate Cox proportional hazards models adjusted for confounding and an inverse probability of treatment-weighted (IPTW) Cox proportional hazards model. Both fever and persistent bacteremia were more common in patients treated empirically with cefepime or piperacillin-tazobactam. Empiric treatment with cefepime or piperacillin-tazobactam did not result in increased mortality relative to that with treatment with carbapenems in patients with hematologic malignancy and ESBL-producing bacteremia, although most patients were changed to carbapenems early in treatment. However, due to prolonged fever and persistent bacteremia, their role may be limited in this patient population.