Over the past decade, DASON physicians and pharmacists have conducted abundant research in the fields of healthcare epidemiology, infection prevention, and multidrug resistant pathogens. Much of this work was conducted in community hospitals through the Duke Infection Control Outreach Network (DICON). It is only because of our unique and long-standing relationship with hospitals in the community that we have been so successful in our research mission.
DASON physicians and pharmacists already have research experience related to antimicrobial stewardship. Here are some examples:
- Assessing antimicrobial selection and outcomes in community hospitals. DASON Investigators studied the antibiotic treatment and outcomes for patients with surgical site infections and/or bloodstream infections (BSI) due to methicillin-resistant Staphylococcus aureus (MRSA). Infection surveillance and microbiology data from 8 community hospitals participating in DICON and a single tertiary care hospital were used in this study. We found that antibiotic management was suboptimal in community hospitals and in the tertiary care center. For example, only 38.3% of patients with BSI due to MRSA received antibiotics with activity against MRSA on the day of diagnosis. This study identified important targets for stewardship quality improvement initiatives and illustrates the important fact that there are important opportunities to improve antimicrobial prescribing practices in community hospitals.
- Limitations of a hospital-wide antibiogram for predicting antimicrobial susceptibility of clinical isolates from patients with prolonged hospitalization. DASON Investigators analyzed antimicrobial susceptibility test results for Pseudomonas aeruginosa isolates from over 3,000 patients at DUH from 2000 through 2007. We found that standard antibiograms became unreliable predictors of susceptibility to antimicrobials after prolonged hospitalization (> 10 days).
- Using unit-specific antibiograms to predict the likelihood of inadequate therapy. DASON Investigators performed a study to determine the feasibility of using the “likelihood of inadequate therapy” (LIT), based on the in vitro susceptibility profiles of infecting organisms within specific ICUs at Duke University Hospital, to determine appropriate empiric antibiotic therapy. Significant differences in the appropriateness of commonly used broad-spectrum antimicrobials were noted between hospital units. For example, piperacillin-tazobactam, one of the most commonly used antimicrobials at DUH, was less effective as empiric therapy in the medical ICU compared to the surgical ICU due to higher rates of drug resistance.
- Predicting infections with extended-spectrum beta lactamase (ESBL) producing organisms. DICON Investigators performed a retrospective study at DUH to develop and validate a clinical risk factor scoring model to identify patients at risk for infection due to ESBL-producing organisms. Patients with recent hospitalization, transfer from another facility, urinary catheterization at the time of infection, recent beta-lactam or fluoroquinolone treatment, and/or immunosuppression were at highest risk. This model was subsequently used to help predict when empiric use of carbapenem therapy is warranted.
With DASON, we hope to build on our prior research successes and begin to critically assess antimicrobial stewardship interventions in real-world community hospital settings. Stay tuned for updates regarding our latest research endeavors!