Competing Interests: Vancomycin Use in Trauma Patients is Similar During Methicillin-Resistant Staphylococcus aureus Nasal Swab Based De-Escalation and Universal Mupirocin Decolonization Protocols.

Introduction: Protocols for vancomycin de-escalation often rely on nasal swab testing for methicillin-resistant Staphylococcus aureus (MRSA). However, in settings of hospital-wide universal MRSA decolonization with nasal mupirocin, these swabs may be unreliable, hindering de-escalation protocols. This study investigated vancomycin use and MRSA infection in trauma patients managed under each of these separate protocols. Methods: This retrospective review compared patients admitted to a Level 1 trauma center during a time-period of MRSA swab-based vancomycin de-escalation ("de-esc") with those admitted during a subsequent period of universal decolonization (and thus "no de-esc"). The primary outcome was total days of vancomycin per patient receiving vancomycin. Additional outcomes included a proportion of patients receiving a short course of vancomycin (<3 d), overall vancomycin rates, and in-hospital MRSA infections. Results: A total of 5,678 patients were evaluated, with 2,891 admitted during the "de-esc" period and 2,787 admitted during universal decolonization ("no de-esc"). There was no difference in the proportion of patients receiving vancomycin during the "de-esc" versus "no de-esc" protocols (7.2% [n = 208] vs. 6.5% [n = 181], p = 0.3). Among these patients, there was also no difference in either total days of vancomycin (5.3 d vs. 5.9 d, p = 0.3) or proportion receiving a short vancomycin course (33% vs. 29%, p = 0.5). There were 56 total patients with MRSA infections, with no difference between the two time periods (1.1% vs. 0.7%, p = 0.07). Conclusion: Despite concerns that a hospital-wide MRSA universal decolonization policy would hinder nasal swab-based vancomycin de-escalation, both vancomycin use and MRSA infection rates remained the same during the two time periods.