Implementation of an automated methicillin-resistant Staphylococcus aureus polymerase chain reaction screening intervention to guide discontinuation of vancomycin for pneumonia.

BACKGROUND

Methicillin-resistant Staphylococcus aureus (MRSA) is a pathogen commonly implicated in pneumonia for which vancomycin is often used to cover empirically. Our study examined the impact of a pharmacy-based automatic MRSA polymerase chain reaction (PCR) nares intervention.

METHODS

We included patients prescribed vancomycin for pneumonia and defined three cohorts: pre-intervention (Cohort 1), post-test implementation (Cohort 2), and post-test implementation with electronic medical record (EMR) enhancements and active stewardship involvement (Cohort 3). The primary outcome was total duration of vancomycin treatment. We performed a desirability of outcome ranking with response adjusted for duration of antibiotic risk (DOOR/RADAR) analysis to prioritize clinical outcomes including adverse events, escalation of care, and death.

RESULTS

The median duration of vancomycin therapy decreased between Cohorts 1 and 2 (55 versus 47 hours, p = 0.15), with a greater decrease detected among the subset of Cohort 2 patients from whom the PCR test was actually collected (42 hours, p = 0.035). Duration of therapy was lowest in Cohort 3 (22.3 hours, p < 0.001). In the DOOR/RADAR analysis, no meaningful difference in clinical outcomes was detected between Cohorts 1 and 2 (p = 0.55). Cohort 3 had substantially better ranked outcomes when compared to Cohorts 1 and 2 (p < 0.001).

CONCLUSION

Vancomycin treatment duration was shorter in patients after a pharmacy-directed, EMR-based MRSA PCR intervention was implemented, with a greater response after implementation of additional EMR enhancements and active stewardship involvement, improving test collection rate and result response. This study will help inform future interventions pairing automated EMR-based interventions with stewardship team efforts.