820. Association between Inappropriate Empirical Antimicrobial Therapy and Hospital Length of Stay in Gram-Negative Bloodstream Infections
Session: Poster Abstract Session: Bacteremia and Endocarditis
Friday, October 9, 2015
Room: Poster Hall
Posters
  • Final ID Week poster.pdf (387.5 kB)
  • Background: Bloodstream Infection (BSI) is an illness with wide variation in prognosis based on acute severity of illness, source of infection and major comorbidities as summarized in the Bloodstream Infection Mortality Risk Score (BSIMRS). Survival benefit from appropriate empirical antimicrobial therapy for gram-negative BSI was demonstrated in patients with guarded predicted prognosis (BSIMRS ≥ 5), but not in those with good predicted prognosis at initial presentation (BSIMRS < 5) leaving potential benefit from appropriate empirical therapy in this group unclear. This retrospective cohort study examined the impact of inappropriate empirical antimicrobial therapy on hospital length of stay (HLOS) in patients with gram-negative BSI after stratification by BSIMRS.

    Methods: Hospitalized adults with first episodes of gram-negative BSI from 2010-2013 at Palmetto Health Hospitals in Columbia, SC, USA were identified. Multivariate Cox proportional hazards regression was used to examine risk factors for prolonged HLOS following gram-negative BSI overall and within each predefined BSIMRS category (< 5 and ≥ 5).

    Results: Among 830 unique patients with gram-negative BSI, 469 and 361 had BSIMRS < 5 and ≥ 5, respectively. Overall, median age was 65 years, 448 (54%) were women, and Escherichia coli was the most common organism 444 (54%). Variables that were independently associated with increased risk of remaining hospitalized following gram-negative BSI included BSIMRS (adjusted hazard ratio [aHR] 1.14 per point, 95% confidence interval [CI] 1.11-1.17, p<0.001) and inappropriate empirical antimicrobial therapy (aHR 1.41, 95% CI 1.07-1.91, p=0.01). After stratification based on BSIMRS, median HLOS with appropriate and inappropriate empirical antimicrobial therapy was 7 and 10 days, respectively, in patients with BSIMRS < 5 (p=0.03); and 13 and 17 days, respectively, in those with BSIMRS ≥ 5 (p=0.02).  

    Conclusion: Inappropriate empirical antimicrobial therapy is associated with prolonged HLOS in patients with gram-negative BSI at both ends of the spectrum of illness. This demonstrates benefit from appropriate empirical antimicrobial therapy in patients with BSIMRS < 5 and adds to previously described survival benefit in those with BSIMRS ≥ 5.

    Sarah Cain, BS1, Joseph Kohn, PharmD, BCPS2, P. Brandon Bookstaver, PharmD, FCCP, BCPS (AQ-ID), AAHIVP3, Julie Ann Justo, Pharm D, MS4, Helmut Albrecht, MD5 and Majdi Al-Hasan, MD5, (1)Univ. of South Carolina Sch. of Med., Columbia, SC, (2)Palmetto Health Richland, Columbia, SC, (3)Department of Clinical Pharmacy and Outcomes Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, SC, (4)Department of Clinical Pharmacy and Outcomes Science, South Carolina College of Pharmacy, University of South Carolina, Columbia, SC, (5)Department of Medicine, Division of Infectious Diseases, University of South Carolina School of Medicine, Columbia, SC

    Disclosures:

    S. Cain, None

    J. Kohn, None

    P. B. Bookstaver, Forest Labs: Grant Investigator and Scientific Advisor , Consulting fee

    J. A. Justo, Cempra Pharmaceuticals: Scientific Advisor , Consulting fee

    H. Albrecht, Gilead: Investigator and Scientific Advisor , Research grant

    M. Al-Hasan, None

    Findings in the abstracts are embargoed until 12:01 a.m. PDT, Wednesday Oct. 7th with the exception of research findings presented at the IDWeek press conferences.