2436. Use of Piperacillin/Tazobactam vs. Cefepime or Carbapenem for Infections due to Serratia, Citrobacter or Enterobacter
Session: Poster Abstract Session: Treatment of AMR Infections
Saturday, October 6, 2018
Room: S Poster Hall
  • JGo IDWeek Poster 2018_FINAL.pdf (1.9 MB)
  • Background: AmpC beta-lactamases are an inducible type of resistance not readily detected by rapid diagnostics. Carbapenems and cefepime are considered the standard of care antibiotics for organisms likely to harbor the AmpC gene. However, data on the efficacy of piperacillin-tazobactam is lacking. The objective of this study is to compare clinical outcomes between piperacillin-tazobactam (PTZ) versus cefepime (FEP) or a carbapenem (CAR) for pneumonia or bacteremia caused by Serratia, Citrobacter, or Enterobacter species.

    Methods: This single-center retrospective cohort study evaluated adult patients admitted between January 2007 to October 2017 with either a blood culture or bronchoalveolar lavage (BAL) positive for either S. marcescens, C. freundii, E. cloacae, or E. aerogenes. Data came from the University of Kentucky Microbiological Laboratory and Center for Clinical and Translational Science (CCTS) Data Bank. Patients included must have received PTZ, FEP, or CAR for at least 72 hours. Patients were excluded if they received other antibiotics as definitive therapy (defined as antibiotic used for majority of treatment), gram-negative combination therapy for more than 72 hours, had isolates resistant to definitive antibiotic therapy, or expired within 48 hours of admission.

    Results: A total of 321 patients were identified (154 PTZ and 167 FEP/CAR). Demographics were similar between the two groups, although patients treated with PTZ tended to be slightly older and admitted to the ICU. More patients in the PTZ group (56.5%) had positive BAL cultures compared to the FEP/CAR group (40.7%) [P=0.0047]. The most common pathogen isolated among both PTZ and FEP/CAR patients was Enterobacter spp. (60.4 % and 56.3% respectively) [P=0.5040]. Overall, 11% of PTZ patients died in-hospital compared to 12.6% of FEP/CAR patients [P=0.6704]. In terms of 30-day readmission rate, 2.6% of PTZ patients and 2.4% of FEP/CAR patients were readmitted within 30 days of discharge [P=0.9076].

    Conclusion: Compared to FEP/CAR, patients with Serratia, Citrobacter, or Enterobacter bacteremia or pneumonia treated with PTZ did not show a significant difference in terms of in-hospital mortality and 30-day readmission rate.

    James Go, PharmD1, Katie L. Wallace, PharmD, BCPS2, David S. Burgess, PharmD, FCCP, FIDP3, Donna R. Burgess, RPh2, Sarah Cotner, PharmD, BCPS4 and Vaneet Arora, MD, MPH, D(ABMM)5, (1)University of Kentucky HealthCare, Lexington, KY, (2)University of Kentucky, College of Pharmacy, Lexington, KY, (3)University of Kentucky College of Pharmacy, Lexington, KY, (4)Pharmacy, University of Kentucky HealthCare, Lexington, KY, (5)Clinical Microbiology, University of Kentucky HealthCare, Lexington, KY


    J. Go, None

    K. L. Wallace, None

    D. S. Burgess, None

    D. R. Burgess, None

    S. Cotner, None

    V. Arora, None

    Findings in the abstracts are embargoed until 12:01 a.m. PDT, Wednesday Oct. 3rd with the exception of research findings presented at the IDWeek press conferences.