Background Methicillin-resistant Staphylococcus aureus (MRSA) is an important cause of pneumonia and clinicians must determine when empiric antimicrobial therapy directed toward MRSA is needed. Objective To evaluate the effect of a pharmacy-driven protocol utilizing the nasal swab MRSA polymerase chain reaction (PCR) test to discontinue vancomycin on duration of vancomycin therapy and clinical outcomes in patients with suspected community-acquired pneumonia (CAP) or healthcare-associated pneumonia (HCAP). Setting A teaching hospital in Huntington, WV, USA. Methods This retrospective study included adult patients who received at least one dose of vancomycin for suspected CAP or HCAP. The pre-intervention group consisted of patients prior to the addition of the nasal swab MRSA PCR test to the CAP/HCAP order set. The post-intervention group consisted of patients after the addition of the nasal swab MRSA PCR test to the CAP/HCAP order set. Main outcome measure The primary outcome was vancomycin hours of therapy. Results Of the 196 patients included in the study, 121 patients were in the pre-intervention group and 75 patients were in the post-intervention group. The median duration of vancomycin therapy was significantly shorter in the post-intervention group than the pre-intervention group (49 vs. 18 h, p < 0.001). There were no statistically significant differences in the secondary outcomes including hospital length of stay, 30-day readmission rate, and in-hospital all-cause mortality. Conclusion The addition of a pharmacy-driven protocol utilizing the nasal swab MRSA PCR test was associated with shorter duration of empiric vancomycin therapy by approximately 31 h per patient without increasing adverse clinical outcomes.
Keywords: CAP; HCAP; MRSA; Nasal swab; Pneumonia; United States; Vancomycin.