1087. agr Dysfunction as an Independent Risk Factor for In-hospital Mortality in Persistent Methicillin-resistant Staphylococcus aureus Bacteremia
Session: Poster Abstract Session: Clinical Infectious Diseases: Bacteremia and Endocarditis
Friday, October 28, 2016
Room: Poster Hall
  • IDweek_2016_Poster_(all_MRSAB).pdf (123.3 kB)
  • Background: We aimed to explore microbiological risk factor of in-hospital mortality in persistent methicillin-resistant Staphylococcus aureusbacteremia (pMRSAB) which is yet poorly understood.

    Methods: A prospectively collected and retrospectively reviewed cohort study was conducted at 10 hospitals in South Korea. Adults who suffered SAB over a 7-year period were reviewed, and pMRSAB was defined as an MRSAB longer than 3 days despite of adequate antimicrobial therapy. Among 1,588 cases of SAB, 866 (54.5%) were MRSAB, and 241 (27.8%) of those were pMRSAB. Blood isolates were analyzable in 172 (71.4%) cases. Functionality of agr locus, spa type, SCCmec type, presence of genes for PVL and PSM-mec, and vancomycin minimum inhibitory concentration (MIC) were determined. Those microbiological factors were analyzed together with clinical factors to reveal the risk factors of in-hospital mortality.

    Results: Among 172 cases of analyzable pMRSAB, 57 (33.1%) were in-hospital mortality. The number of agr dysfunction was significantly higher in in-hospital mortality than in survival (75.4%, 43/57 vs. 52.2%, 60/115, P=0.008). SCCmec type, positivity of PVL and PSM-mec genes, and vancomycin MIC were not significantly different between those groups. In multivariable analysis with clinical factors including Charlson’s comorbidity weighted index score, Pitt bacteremia score, and pneumonia as a primary infection foci, agr dysfunction was revealed as an independent risk factor for in-hospital mortality in pMRSAB (adjusted odds ratio, 2.38; 95% confidence interval, 1.12-5.04, P=0.024) (Table).

    Conclusion: agr dysfunction is an independent risk factor for in-hospital mortality in pMRSAB.

    Survival (n=115)

    In-hospital Mortality (n=57)

    Univariate OR (95% CI)

    Multivariate OR (95% CI)

    Charlson’s comorbidity index (±SD)

    4.6 (± 2.7)

    5.8 (± 2.7)

    1.18 (1.05-1.33)a

    1.16 (1.02-1.32)b

    Pitt bacteremia score, median (IQR)

    1.0 (0.0-2.0)

    2.0 (1.0-4.0)

    1.28 (1.09-1.50)a

    1.25 (1.05-1.48)b

    Pneumonia (%)

    2 (1.7)

    9 (15.8)

    10.59 (2.21-50.87)a

    5.70 (1.12-28.95)b

    agr dysfunction (%)

    60 (52.2)

    43 (75.4)

    2.82 (1.39-5.70)a

    2.38 (1.12-5.04)b

    OR, odds ratio; CI, confidence interval; SD, standard deviation; IQR, interquartile range

    a P < 0.01; b P < 0.05

    Chang Kyung Kang, MD1, Sook-in Jung, MD2, Chung-Jong Kim, MD1, Kyoung-Ho Song, MD1, Eu Suk Kim, MD1, Seung Ji Kang, MD2, Nak-Hyun Kim, MD3, Wan Beom Park, MD3, Young Keun Kim, MD4, Hee-Chang Jang, MD5, Shinwon Lee, MD6, Yeon-Sook Kim, MD7, Yee Gyung Kwak, MD8, Ki Tae Kwon, MD9, Sungmin Kiem, MD10, Hong Bin Kim, MD, PhD1 and the Korea INfectious Diseases (KIND) study group, (1)Seoul National University Bundang Hospital, Seongnam, Korea, The Republic of, (2)Chonnam National University Hospital, Gwangju, Korea, The Republic of, (3)Seoul National University Hospital, Seoul, Korea, The Republic of, (4)Yonsei University Wonju Severance Christian Hospital, Wonju, Korea, The Republic of, (5)Chonnam National University Hwasun Hospital, Hwasun, Korea, The Republic of, (6)Pusan National University Hospital, Busan, Korea, The Republic of, (7)Chungnam National University Hospital, Daejeon, Korea, The Republic of, (8)Inje University Ilsan Paik Hospital, Goyang, Korea, The Republic of, (9)Daegu Fatima Hospital, Daegu, Korea, The Republic of, (10)Inje University Haeundae Paik Hospital, Busan, Korea, The Republic of


    C. K. Kang, None

    S. I. Jung, None

    C. J. Kim, None

    K. H. Song, None

    E. S. Kim, None

    S. J. Kang, None

    N. H. Kim, None

    W. B. Park, None

    Y. K. Kim, None

    H. C. Jang, None

    S. Lee, None

    Y. S. Kim, None

    Y. G. Kwak, None

    K. T. Kwon, None

    S. Kiem, None

    H. B. Kim, None

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