383: Impact of Universal Decolonization With Mupirocin on Bloodstream Infections in a Medical Icu

Introduction: Universal decolonization with intranasal mupirocin in the intensive care unit (ICU) has been associated with reduced rates of methicillin-resistant Staphylococcus aureus (SA) clinical isolates and nosocomial bloodstream infections in prospective trials. Real-world experience describing the implementation and impact of universal decolonization in a medical ICU (MICU) population is lacking. The objective of this study is to assess the impact of a universal decolonization protocol with intranasal mupirocin on hospital-acquired bloodstream infections among MICU patients. Methods: A single-center, retrospective analysis of adult patients admitted to the MICU at Barnes-Jewish Hospital was performed. A quality improvement protocol began on January 8, 2024, instructing providers to order intranasal mupirocin 2% ointment twice daily for 5 days for universal decolonization on all new admissions. Patients admitted to the MICU from January 8, 2024 to December 31, 2024 were compared to patients admitted in the 6 months prior to starting universal decolonization. The primary outcome was hospital-acquired bloodstream infections. Results: 1443 patients were included in the pre-protocol group and 2520 patients in the post-protocol group. Patients in the pre- and post-protocol groups had similar median modified APACHE II scores (17 IQR 13-23 vs 17 IQR 13-23, p=0.65), septic shock incidence (23.8% vs 23.5%, p=0.83), central line placement rates (39.2% vs 40.4%, p=0.45), and mechanical ventilation rates (35.2% vs 36.7%, p=0.34). The percent of patients who had blood cultures drawn at least once was also similar (75.2% in the pre-protocol group vs 77.7% in the post-protocol group, p=0.09). No difference was observed in the rate of hospital-acquired bloodstream infections after universal decolonization was implemented (3.5% pre-protocol vs 3.6% post-protocol, p=0.94). Significantly lower rates of bacteremia due to SA were observed in the post-protocol group (0.7% vs 1.4%, p=0.03). Conclusions: In a MICU population, implementation of a universal decolonization protocol with intranasal mupirocin twice daily for 5 days was not associated with a decreased rate of all-cause hospital-acquired bloodstream infections, but was associated with lower rates of SA bacteremia.