Session: Poster Abstract Session: Clinical Infectious Diseases: Respiratory Infections
Friday, October 28, 2016
Room: Poster Hall
  • overprescription of antibiotics_Final.pdf (1.1 MB)
  • Background: Due to a growing concern for Methicillin-Resistant Staphylococcus aureus (MRSA), the IDSA has recently recommended adding vancomycin to the standard inpatient therapy (fluoroquinolones or beta-lactam plus a macrolide) for patients with community-acquired pneumonia (CAP) in the ICU. Many physicians also prescribe antibiotics to cover Pseudomonas aeruginosa despite these recommendations. The aim of this study is to evaluate the prevalence of MRSA and P. aeruginosa and appropriate choice of antibiotics in this population.

    Methods: A retrospective records review was performed for patients who had CAP and were admitted to the ICU at the University of Arizona between November 2013 and December 2014.

    Results: A total of 147 patients were included. Mean age was 61.8 years (SD 17.3). Approximately 50% of the patients were male, 77.8% were White, and 30.8% were Hispanic. Only three patients (2%) had a history of recent influenza. Fifty-one patients had chronic obstructive pulmonary disease (26.7%). Seven patients had a history of positive MRSA nasal screen (7/83, 8.4%). Respiratory samples were obtained in 80 patients (54.4%) and were positive for MRSA in six patients, P. aeruginosa in one, and Streptococcus pneumoniae in twelve patients. A total of 136 patients (94.4%) received antibiotics including 74 (50.7%) who received coverage against MRSA, 84 (57.5%) who received coverage against P. aeruginosa, and 114 (78.1%) who received coverage against atypical organisms. Factors associated with positive respiratory culture for MRSA were necrotizing pneumonia and positive MRSA nasal screen. Readmission and escalation of care, defined as broadening of antibiotics or intubation after 48 hours, did not differ between patients receiving coverage against MRSA or P. aeruginosa compared to those who did not.

    Conclusion: Overprescription of antibiotics in the ICU for patients with CAP remains a significant problem. Our study shows that in patients admitted with CAP to the ICU, P. aeruginosa is rare, and coverage against this organism may not be indicated in the abscence of cystic fibrosis or prior pseudomonal infection. Coverage against MRSA should likely be reserved for selected patients, such as those with necrotizing pneumonia and history of positive MRSA swab.

    Rorak Hooten, MD1, Jose Luis Marquez, MD1, Kady Goldlist, MD1, Rafael Urcis, MD2, Matthew Adams, MD1, Kathryn Matthias, PharmD3, David Nix, PharmD3 and Mayar Al Mohajer, MD FACP2, (1)University of Arizona, Tucson, AZ, (2)Division of Infectious Diseases, University of Arizona College of Medicine, Tucson, AZ, (3)University of Arizona College of Pharmacy, Tucson, AZ


    R. Hooten, None

    J. Luis Marquez, None

    K. Goldlist, None

    R. Urcis, None

    M. Adams, None

    K. Matthias, None

    D. Nix, None

    M. Al Mohajer, None

    Findings in the abstracts are embargoed until 12:01 a.m. CDT, Wednesday Oct. 26th with the exception of research findings presented at the IDWeek press conferences.