160. Patterns of Empiric Antibiotic Therapy among Hospitalized Patients with Complicated Intra-Abdominal Infections (cIAI) or Complicated Urinary Tract Infections (cUTI) due to Enterobacteriaceae
Session: Poster Abstract Session: Antimicrobial Stewardship: Current State and Future Opportunities
Thursday, October 8, 2015
Room: Poster Hall

Background: Enterobacteriaceae are commonly implicated in cIAI and cUTI. Current patterns of empiric treatment among hospitalized patients with these infections are not well understood.

Methods: Using Premier database, which contains information from ~150 US hospitals, we identified all admissions of patients aged ≥18 yrs between July 1, 2011 and September 30, 2014 with evidence of cIAI and/or cUTI. The date of the earliest positive culture for Gram-negative bacteria was deemed the “index date”, and all patients were required to have evidence of Enterobacteriaceae infection on this date.  Carbapenem-resistant Enterobacteriaceae (CRE) was defined as an index isolate that was non-susceptible (i.e., “resistant” or “intermediate”) to ≥1 carbapenems (i.e., doripenem, meropenem, imipenem, ertapenem). Empiric therapy was defined as all antibiotics received on this date and/or the 2-day period thereafter.

Results: A total of 3,603 cIAI patients and 28,757 cUTI patients met all selection criteria; 1% of each cohort had CRE. Among CRE patients, commonly used initial antibiotics with Gram-negative activity were ceftriaxone (27% of all such patients), piperacillin-tazobactam (24%), levofloxacin (18%), and cefepime (18%); corresponding agents among non-CRE patients were ceftriaxone (47%), piperacillin-tazobactam (26%), levofloxacin (22%), and cefepime (8%). Thirty-seven percent of CRE and 21% of non-CRE patients received vancomycin. Only 29% of CRE patients received empiric therapy with aminoglycosides, polymyxin, or tigecycline, all of which have in vitro activity against CRE; the corresponding value among non-CRE patients was 10% (Figure). Seventy-four percent of CRE patients and 79% of non-CRE patients who received one of these three types of antibiotics also received beta-lactams empirically.

Conclusion:  Patterns of empiric therapy among patients with CRE differed from that of patients without. Only one in four CRE patients received empiric therapy with in vitro activity against CRE.


Tarun Bhagnani, MS1, Thomas Lodise, PharmD, PhD2, Rosa Wang, MHA1, Sharvari Bhurke, MS1, Qi Zhao, MD, MPH3 and Ariel Berger, MPH1, (1)Evidera, Inc, Lexington, MA, (2)Pharmacy Practice, Albany College of Pharmacy and Health Sciences, Albany, NY, (3)Actavis, Inc, Jersey City, NJ


T. Bhagnani, Actavis, Inc: Research Contractor , Research support

T. Lodise, Actavis, Inc: Consultant , Consulting fee

R. Wang, Actavis, Inc: Research Contractor , Research support

S. Bhurke, Actavis, Inc: Research Contractor , Research support

Q. Zhao, Actavis, Inc: Employee , Salary

A. Berger, Actavis, Inc: Research Contractor , Research support

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