894. Treating Healthcare-Associated Pneumonia (HCAP) Requires Therapy Against P. aeruginosa and Methicillin-resistant S. aureus (MRSA)
Session: Poster Abstract Session: Respiratory Infections
Friday, October 4, 2013
Room: The Moscone Center: Poster Hall C
  • HCAP poster idweek13 894.pdf (289.9 kB)
  • Background: Current guidelines recommend that patients with HCAP receive empiric antibiotics (ABX) similar to those used for hospital-acquired pneumonia (HAP); however, there is little data characterizing the bacteriology and risk factors for specific pathogens in patients with HCAP. The purpose of this study is to describe the bacterial pathogens causing HCAP at our institution and determine optimal empiric ABX regimens. 

    Methods: The medical records of adult inpatients from April 2010 – March 2012 who had a respiratory culture obtained within 48 hours of admission positive for a bacterial pathogen were randomly reviewed to select 95 patients who met study criteria. Patients who had HCAP risk factors and clinical signs of pneumonia were included. Patients transferred from an outside hospital or with cystic fibrosis were excluded.  Susceptibilities of pathogens were analyzed with respect to the following 3 ABX regimens:  community-acquired pneumonia (CAP) regimen [ceftriaxone plus azithromycin], a two-drug (2D) HAP regimen [vancomycin plus piperacillin-tazobactam], and a three-drug (3D) HAP regimen [the 2D-HAP regimen plus amikacin]. Adequacy was defined as susceptibility of all isolated pathogens from a given culture to at least one ABX from the associated regimen. HCAP risk factors were assessed for association with certain pathogens. 

    Results:  The most common pathogens identified were P. aeruginosa (21%) and S. aureus(MSSA 11%; MRSA 25%). Antibiotic adequacy for the CAP, 2D-HAP, and 3D-HAP-regimens was 37%, 93%, and 98%, respectively (p < 0.001 for CAP vs. either HAP regimen). Association of individual risk factors and common pathogens is summarized below:

    Risk Factor

    P. aeruginosa

    No. (%)


    No. (%)

    P. aeruginosa or MRSA

    No. (%)

    Long-term care facility (n=21)

    5 (24)

    9 (43)

    14 (67)

    Dialysis (n=18)

    6 (33)

    5 (28)

    11 (61)

    Recent hospitalization (n=71)

    17 (24)

    19 (27)

    36 (51)

    Conclusion: In treating HCAP at our institution, an empiric ABX regimen that targets P. aeruginosa and MRSA is essential. The addition of an aminoglycoside to piperacillin-tazobactam and vancomycin may not be necessary in all HCAP patients.

    Stephen Vickery, PharmD1, Johnson James, PharmD1, James Beardsley, PharmD1, John Williamson, PharmD1, Christopher Ohl, MD2 and Vera Luther, MD2, (1)Wake Forest Baptist Health, Winston-Salem, NC, (2)IM-Section On Infectious Diseases, Wake Forest School of Medicine, Winston-Salem, NC


    S. Vickery, None

    J. James, None

    J. Beardsley, None

    J. Williamson, None

    C. Ohl, None

    V. Luther, 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.