2452. Treatment and Outcomes of Daptomycin-Nonsusceptible Methicillin-Resistant Staphylococcus aureus Bloodstream Infections
Session: Poster Abstract Session: Treatment of AMR Infections
Saturday, October 6, 2018
Room: S Poster Hall
Posters
  • DNS MRSA treatment and outcomes1.pdf (447.7 kB)
  • Background:

    Daptomycin (dap) is approved as an alternative to vancomycin (van) for therapy of methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infection (BSI). Cases of therapy failure associated with the emergence of daptomycin-nonsusceptible (DNS) MRSA strains have been documented. Information on the treatment and outcome of DNS MRSA BSI is scarce. This study describes the treatment and outcome of patients (pts) with DNS MRSA BSI at our healthcare center.

    Methods:

    This is a retrospective review of pts with DNS (E-test MIC >1.0 µg/mL) MRSA BSI at a tertiary healthcare center in Detroit, Michigan between 9/24/2005 and 3/31/2018. The variables collected were: BSI source, inpatient and discharge antibiotic therapy, BSI duration, in-hospital and 90-day mortality, and 90-day MRSA BSI recurrence. Inpatient therapy was defined as the treatment used for the most consecutive days from index DNS MRSA blood culture during hospitalization. Discharge therapy is the treatment used post-discharge or on the expiration date. Antibiotics used for ≤ 2 days were excluded.

    Results:

    A total of 32 non-duplicate pts with DNS MRSA BSI were identified. One pt with an inaccessible chart was excluded. The source of BSI was endovascular in 9 (29%) pts, secondary BSI in 14 (45%), central-line associated in 3 (10%), and unknown in 5 (16%). A total of 24 different antibiotic regimens were used to treat DNS MRSA BSI. Van monotherapy was the most commonly used regimen for inpatient and discharge therapy, followed by dap + ceftaroline (cef). Table 1 is a summary of the results.

    Table 1: Treatment and outcomes of pts with DNS MRSA BSI

    Inpatient therapy

    Discharge therapy

    (n)

    In-hospital mortality

    n(%)

    90-day

    mortality

    n(%)

    Mean BSI duration

    (days)

    90-day BSI recurrence

    n(%)

    van (10)

    van (8)

    cef (1)

    dap + cef (1)

    3(30)

    4(40)

    2.9

    3(30)*

    dap + cef ( 5)

    cef + dap (3)

    cef + van (1)

    van (1)

    0(0)

    0(0)*

    4.4

    1(20)**

    lin ± gen ± rif (5)

    lin (3)

    van + sxt (1)

    quin/dal (1)

    1(20)

    3(60)

    6.8

    1(20)

    other (11)

    4(36)

    4(36)

    3.5

    2(22)*

    Totals

    6(26)

    11(35)

    4.4

    7(23)

    gen = gentamycin; rif = rifampin; lin = linezolid; sxt = TMP-SMX; quin/dal = quinupristin/dalfopristin.

    *1 pt with unknown status

    ** 3 pts with unknown status

    Conclusion:

    A variety of therapeutic regimens was used to treat DNS MRSA BSI in our cohort. However, van monotherapy was the most common inpatient and discharge regimen.

    Hind Hadid, MD1, Ana Cecilia Bardossy, MD2, Helina Misikir, MPH3, Mary Beth Perri, MT2, Marcus Zervos, MD4 and Erica Herc, MD2, (1)Infectious Disease, Henry Ford Health System, Detroit, MI, (2)Infectious Diseases, Henry Ford Health System, Detroit, MI, (3)Henry Ford Hospital, Detroit, MI, (4)Infectious Diseases, Henry Ford Health Systems, Detroit, MI

    Disclosures:

    H. Hadid, None

    A. C. Bardossy, None

    H. Misikir, None

    M. B. Perri, None

    M. Zervos, None

    E. Herc, 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.