381. Risk Factors and Outcomes Associated with Daptomycin-Resistant Enterococcal Infection
Session: Poster Abstract Session: MRSA, MSSA, Enterococci
Thursday, October 3, 2013
Room: The Moscone Center: Poster Hall C
Posters
  • IDWeek Poster Handout JK.pdf (335.2 kB)
  • Background: Emergence of daptomycin-resistant enterococci (DRE) has been reported in the United States.  Review of the 2011 antibiogram at the Penn State Milton S. Hershey Medical Center revealed a large number of DRE, all of which were Enterococcus faecium (E. faecium).  The purpose of this study was to describe the characteristics, potential risk factors, and outcomes of patients with confirmed DRE infections.  

    Methods: A retrospective case-series of patients who were at least 18 years of age and had E. faecium cultured from at least one specimen between June, 2010, and August, 2012, that was resistant to daptomycin by automated sensitivity testing and confirmed by an E-test. 

    Results: We identified 19 adult patients with E-test-confirmed DRE cultured from at least one sample over a 27-month period.  DRE bacteremia was the most common type of infection among these patients (47%), followed by urine and wound infections (21% each).  All 9 patients with DRE bacteremia had indwelling vascular access devices, which had been in for a median duration of 22 days (range 8 – 49 days).  Underlying diseases in these patients included malignancy (42%), gastrointestinal disease (42%), and diabetes (32%), with several patients having more than 1 comorbidity.  All of the DRE isolates were E. faecium, including 15 of 19 (79%) that also were vancomycin-resistant.  Only 4 of the 19 patients (21%) had prior exposure to daptomycin.  The most commonly prescribed empiric Gram-positive therapy for these patients was vancomycin (53%), and most of these patients were switched to linezolid (68%).  Fifteen of the patients (79%) survived the index hospitalization.  Of the 4 patients who expired, 3 had DRE bacteremia and 1 had DRE wound infection.  None of the 4 who expired had a history of VRE or previous exposure to daptomycin; however, 3 of 4 had a prior or concurrent Gram-negative infection and all 4 had daptomycin-resistant VRE.

    Conclusion: Resistance to daptomycin was observed in many isolates of E. faecium, and previous exposure to daptomycin was not necessary.  DRE bacteremia was the most common type of infection and was associated with prolonged duration of indwelling vascular access devices.  The presence of malignancy, gastrointestinal disease, and diabetes appear to be risk factors for DRE infection.

    Kristy Tsau, PharmD1, Jihye Kim, PharmD1 and Michael Katzman, MD, FIDSA2, (1)Pharmacy, Penn State Hershey Medical Center, Hershey, PA, (2)Internal Medicine, Penn State Hershey Medical Center, Hershey, PA

    Disclosures:

    K. Tsau, None

    J. Kim, None

    M. Katzman, None

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