1733. Patterns of Antibiotic Utilization for MRSA Bloodstream Infections (BSI) with Vancomycin (V) MIC 1.5-2.0 mg/L: A Multi-center Evaluation
Session: Poster Abstract Session: Treatment of Bacteremia and Endocarditis
Saturday, October 5, 2013
Room: The Moscone Center: Poster Hall C
Posters
  • IDWeek_Patterns_of_DAP_Use_Poster_10-5-2013.pdf (120.9 kB)
  • Background: Mounting evidence suggests that V efficacy declines for treatment of MRSA BSI with V MIC >1. IDSA MRSA guidelines recommend assessment of response, independent of MIC. To our knowledge no multicenter evaluation has investigated patterns of antibiotic utilization & impact of earlier switch from V to daptomycin (D) for MRSA BSI with V MIC >1.

    Methods: Multicenter, retrospective investigation of patterns of antibiotic use in MRSA BSI with V MIC 1.5-2. Early D was defined as ≤2 d prior V, & late D defined as 3-5 d prior V.

    Results: Patients (pts) from 11 US hospitals were enrolled; 93 received D (2007 – 2012 yrs). A minority (17%) received D with no prior V. The majority (83%) were switched from V to D, after 1 (n=18), 2 (n=16), 3 (n=26), 4 (n=14), or 5 (n=3) d. Concomitant gentamicin was primarily used in endovascular infections (endocarditis, mycotic aneurysm/ septic thrombophlebitis, or unknown source) (10/12 [83%]). Concomitant rifampin use was primarily in bone/skin infections (8/14 [57%]). Concomitant antibiotics did not measurably impact outcomes. Most common reasons for switch: V MIC (35%), MD preference (12%), V failure (10%), V toxicity/intolerance (5%), consolidation (5%), V dosing/level issues (3%). D dose was slightly higher if V failure documented as switch reason (median, 7 vs 6 mg/kg, p=0.097). Early D switch was more commonly due to MD preference (24% vs 2%, p=0.005) or V toxicity/intolerance (12% vs 0%, p=0.021). Initial or early D use was also noted in pts with higher APACHE II scores (median, 15 vs 12, p=0.016). However, no relationship was noted between time to bacteremia clearance (by 4 & 7 d, respectively) & APACHE II scores (≥15 vs. <15) (p=0.484 & p=0.472, respectively).

    Conclusion: In this multicenter evaluation of contemporary management of MRSA BSI, patterns of antibiotic utilization varied. A small subset received concomitant therapy, related to bacteremia source, but did not impact outcomes. Over 1/3 were switched from V to D due to V MIC. Earlier D was associated with MD preference, V toxicity, & critically ill patients. Sample size & colinearity with critical illness scores precluded multivariable analysis of outcomes. Our results demonstrate significant differences between patients given early D vs late D for MRSA BSI when V MIC is >1.

    Pamela A. Moise, PharmD1, Darren L. Culshaw, PharmD1, Annie Wong-Beringer, PharmD2, Joyce Bensman, PharmD2, Kenneth Lamp, PharmD1, Winter J. Smith, PharmD3, Karri Bauer, PharmD4, Debra A. Goff, PharmD4, Robert Adamson, PharmD5, Kimberly Leuthner, PharmD6, Michael Virata, MD7, James A. Mckinnell, MD8, Saira B. Chaudhry, PharmD, MPH9, Romic Eskandarian, PharmD10, Thomas Lodise, PharmD11 and Marcus Zervos, MD12, (1)Cubist Pharmaceuticals, Lexington, MA, (2)University of Southern California, Los Angeles, CA, (3)University of Oklahoma Health Sciences Center, Oklahoma City, OK, (4)The Ohio State University Medical Center, Columbus, OH, (5)St. Barnabas Health Care System, Livingston, NJ, (6)University Medical Center of Southern Nevada, Las Vegas, NV, (7)Infectious Diseases, Yale-New Haven Hospital-SRC, New Haven, CT, (8)Torrance Memorial & Harbor-UCLA, Torrance, CA, (9)Jersey Shore University Medical Center and Rutgers University, Neptune, NJ, (10)Glendale Adventist Medical Center, Glendale, CA, (11)Albany College of Pharmacy, Albany, NY, (12)Infectious Diseases, Henry Ford Hospital, Detroit, MI

    Disclosures:

    P. A. Moise, Cubist Pharmaceuticals: Employee and Shareholder, Salary

    D. L. Culshaw, Cubist Pharmaceuticals: Employee and Shareholder, Salary

    A. Wong-Beringer, Cubist Pharmaceuticals: Investigator, Research support

    J. Bensman, None

    K. Lamp, Cubist: Employee and Shareholder, Salary

    W. J. Smith, Cubist Pharmaceuticals: Investigator, Research support

    K. Bauer, Cubist Pharmaceuticals: Investigator, Research support

    D. A. Goff, Cubist Pharmaceuticals: Investigator, Research support

    R. Adamson, Cubist Pharmaceuticals: Investigator, Research support

    K. Leuthner, Cubist Pharmaceuticals: Investigator, Research support

    M. Virata, Cubist Pharmaceuticals: Investigator, Research support

    J. A. Mckinnell, Cubist Pharmaceuticals: Investigator, Research support

    S. B. Chaudhry, Cubist Pharmaceuticals: Investigator, Research support

    R. Eskandarian, Cubist Pharmaceuticals: Investigator, Research support

    T. Lodise, Cubist Pharmaceuticals: Consultant and Grant Investigator, Consulting fee and Research grant

    M. Zervos, Cubist Pharmaceuticals: Investigator, Research support

    Findings in the abstracts are embargoed until 12:01 a.m. PST, Oct. 2nd with the exception of research findings presented at the IDWeek press conferences.