1255. The Epidemiology, Clinical Characteristics and Outcomes of Patients with Nosocomial Pneumonia caused by Community-Acquired Methicillin-Resistant Staphylococcus aureus (CA-MRSA)
Session: Poster Abstract Session: Staphylococcal Resistance and Epidemiology
Saturday, October 22, 2011
Room: Poster Hall B1
Handouts
  • ZY11-092 NP CA-MRSA - IDSA11.pdf (795.4 kB)
  • Background:  Little is known about the characteristics and outcomes of patients who develop NP caused by CA-MRSA. 

    Methods: We identified all patients with NP caused by CA-MRSA enrolled in an international, double-blind, randomized, controlled trial of linezolid (LZD; 600 mg twice daily) vs. vancomycin (VAN; 15mg/kg twice daily) for NP caused by MRSA. We defined CA-MRSA as a baseline MRSA isolate from an adequate respiratory specimen that was SCCmec type IV, PVL+.  Non-CA-MRSA was defined as a baseline MRSA isolate that was SCCmec type I, II, III, or IV, PVL-. Outcomes at end of study (EOS) were assessed 7-30d after end of therapy.

    Results: In total, 48/385 patients (12.5%) with confirmed MRSA had CA-MRSA NP.  Patient characteristics and outcomes varied by group CA-MRSA status (Table).  At EOS, patients with CA-MRSA had numerically lower clinical success (total CA-MRSA 41.9%, LZD 36.4%, VAN 47.6%) vs. patients with non-CA-MRSA (total non CA-MRSA 54.0%; LZD 60.6%, VAN 48.1%). Patients with CA-MRSA had similar microbiologic success (total CA-MRSA 51.0%; LZD 54.2%, VAN 47.6%) vs. patients with non-CA-MRSA (total non-CA-MRSA 54.0%; LZD 59.6%, VAN 48.8%).

    Conclusion: CA-MRSA is a cause of NP.   Clinical success rates were numerically lower and microbiologic success rates and Day 28 mortality were similar among patients with CA-MRSA compared with those with non-CA-MRSA.

    Table. Demographics, clinical and microbiologic characteristics, and outcomes of patients with NP caused by CA-MRSA and non-CA-MRSA.   

     

    CA-MRSA

    (n=48)

    Non-CA-MRSA

    (n=337)

    P value

    Age, y, mean (SD)

    53.6 (17.8)

    62.7 (18.0)

    <0.05

    Black, n (%)

    12 (25.0)

    34 (10.1)

    <0.05

    CXR, n (%)

      Bilateral

      Unilateral

      Pleural effusions

    -

    31 (64.6)

    17 (35.4)

    17 (35.4)

    -

    231 (68.5)

    105 (31.2)

    156 (46.3)

    -

    0.62

    0.62

    0.17

    Comorbidity, n (%)

      Pulmonary disease

      Cardiac disease

    -

    39 (81.3)

    21(43.8)

    -

    224 (66.5)

    209 (62.0)

    -

    <0.05

    <0.05

    APACHE II ≥ 15, n (%)

    30 (62.5)

    220 (65.3)

    0.75

    Bacteremia, n (%)

    5 (10.4)

    29 (8.6)

    0.79

    Ventilated at baseline, n(%)

    37 (77.1)

    238 (70.6)

    0.40

    Vancomycin MIC, n (%)

      ≤ 0.5

      1

      ≥ 2

    -

    3(6.3)

    18 (37.5)

    27 (56.3)

    -

    11( 3.3)

    152 (45.1)

    171 (50.7)

    -

    0.40

    0.35

    0.54

    Mortality at D 28, n (%)

             7 (14.6)          61 (18.1)         0.54

     


    Subject Category: C. Clinical studies of bacterial infections and antibacterials including sexually transmitted diseases and mycobacterial infections (surveys, epidemiology, and clinical trials)

    David Huang, MD, PhD, MPH1, G. Ralph Corey2 and Vance Fowler, MD2, (1)Specialty Care Medicines Development Group, Pfizer Inc, Collegeville, PA, (2)Duke University Medical Center, Durham, NC

    Disclosures:

    D. Huang, Pfizer Inc: Employee, Salary

    G. R. Corey, Pfizer Inc: Scientific Advisor, Consulting fee

    V. Fowler, Astellas, Cubist, Inhibitex, Merck, Johnson & Johnson, Leo Pharmaceuticals, NovaDigm, The Medicines Company, Baxter Pharmaceuticals, Biosynexus, Shire, Inimex, Galderma : Consultant, Consulting fee
    NIH Astellas Cubist Merck Theravance Cerexa Pfizer Novartis Advanced Liquid Logic Inhibitex : Grant Investigator, Grant recipient
    UpTo Date: Member, Licensing agreement or royalty
    Arpida Astellas Cubist Inhibitex Merck Pfizer Targanta Theravance Wyeth Ortho-McNeil Novartis Vertex Pharmaceuticals Medimmune: speaker, Speaker honorarium

    Findings in the abstracts are embargoed until 12:01 a.m. EST Thursday, Oct. 20 with the exception of research findings presented at IDSA press conferences.