1741. Impact of Staphylococcal Cassette Chromosome mec (SCCmec) type on Mortality Attributed to Methicillin-Resistant Staphylococcus aureus Bacteremia
Session: Poster Abstract Session: Treatment of Bacteremia and Endocarditis
Saturday, October 5, 2013
Room: The Moscone Center: Poster Hall C
Posters
  • IDweek_2013_Poster.pdf (95.7 kB)
  • Background: This study was designed to explore the impact of staphylococcal cassette chromosome mec (SCCmec) type on mortality attributed to methicillin-resistant Staphylococcus aureusbacteremia (MRSAB).

    Methods: A retrospective cohort study was conducted at a tertiary-care hospital. All adults with MRSAB over a 4-year period were enrolled. SCCmec type was determined for all the isolates. Cases of SCCmectype II and III were grouped together and were compared to the cases of type IV. MRSAB-attributed mortality is defined as a death with at least one of the followings; documented MRSAB at the time of death, presence of persistent focus of MRSAB and sign of sepsis, and death within 14 days of MRSAB without other plausible explanations.

    Results: Among 179 cases, 45 (25%) were MRSAB-attributed death, and the numbers of SCCmec type II/III and IV were 130 (73%) and 49 (27%). MRSAB-attributed mortality was higher in SCCmec type II/III (30%, 39/130) than in type IV (12%, 6/49) (P=0.010). In multivariate analyses, higher Charlson’s comorbidity index score, higher Pitt bacteremia score, and central line associated infection were independently associated with MRSAB-attributed mortality. SCCmec type II/III compared to type IV was also correlated to MRSAB-attributed mortality with borderline statistical significance (multivariate odds ratio, 3.04; 95% confidence interval, 0.96-9.59, P=0.058) (Table).

    Conclusion: In MRSAB, SCCmectype II/III compared to type IV tended to correlate to MRSAB-attributed mortality.

     

    Survivor (n=134)

    Non-survivor (n=45)

    Univariate OR (95% CI)

    Multivariate OR (95% CI)

    Charlson’s comorbidity index

    4.7 (±2.7)

    6.1 (±2.7)

    1.20 (1.06-1.35)a

    1.25 (1.06-1.47)a

    Pitt bacteremia score

    1.5 (±1.8)

    4.7 (±4.0)

    1.51 (1.29-1.76)a

    1.55 (1.29-1.86)a

    Primary bacteremia

    15 (11.2)

    12 (26.7)

    2.89 (1.23-6.76)b

    1.35 (0.41-4.41)

    Central line associated infection

    50 (37.3)

    9 (20.0)

    0.42 (0.19-0.94)b

    0.31 (0.10-0.95)b

    Bone & joint infection

    12 (9.0)

    0 (0)

    NAb

    NA

    Pneumonia

    9 (6.7)

    7 (15.6)

    2.56 (0.89-7.33)c

    0.71 (0.17-2.96)

    Intra-abdominal infection

    5 (3.7)

    5 (11.1)

    3.23 (0.89-11.71)c

    1.43 (0.17-11.97)

    SCCmec type II/III (versus type IV)

    91 (67.9)

    39 (86.7)

    3.07 (1.21-7.81)b

    3.04 (0.96-9.59)c

    Vancomycin MIC ≥ 1.5 (E-test)

     72 (53.7)

     19 (42.2)

    0.63 (0.32-1.25) 

     

    OR, odds ratio; CI, confidence interval; NA, not available, MIC, minimum inhibitory concentration

    a P < 0.01; b P < 0.05; c P < 0.10

    Chang Kyung Kang, MD1,2, Nak-Hyun Kim, MD3, Chung-Jong Kim, MD4,5, Taek Soo Kim2,6, Kyoung-Ho Song1,2, Pyoeng Gyun Choe, MD4, Wan Beom Park6, Ji-Hwan Bang, MD, PhD1, Eu Suk Kim1,2, Kyoung Un Park, MD, PhD2,7, Sang Won Park, MD, PhD1, Nam-Joong Kim, MD, PhD1, Myoung-Don Oh6 and Hong Bin Kim1,2, (1)Department of Internal Medicine, Seoul National University College of Medicine, Seoul, South Korea, (2)Seoul National University Bundang Hospital, Seongnam, South Korea, (3)Department of Internal Medicine, Seoul National University Hospital, Seoul, South Korea, (4)Internal Medicine, Seoul National University College of Medicine, Seoul, South Korea, (5)Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, South Korea, (6)Seoul National University College of Medicine, Seoul, South Korea, (7)Laboratory Medicine, Seoul National University College of Medicine, Seoul, South Korea

    Disclosures:

    C. K. Kang, None

    N. H. Kim, None

    C. J. Kim, None

    T. S. Kim, None

    K. H. Song, None

    P. G. Choe, None

    W. B. Park, None

    J. H. Bang, None

    E. S. Kim, None

    K. U. Park, None

    S. W. Park, None

    N. J. Kim, None

    M. D. Oh, None

    H. B. Kim, None

    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.