262. Epidemiology, Treatment, and Clinical Outcomes of Methicillin-Sensitive Staphylococcus aureus (MSSA) Bacteremia Complicated by Central Nervous System (CNS) Disease within the Veterans Affairs (VA) Healthcare System

Abstract

Abstract Background The epidemiology of methicillin-sensitive Staphylococcus aureus (MSSA) bacteremia (BSI) complicated by central nervous system (CNS) involvement is not well defined or described. We aimed to identify patients with MSSA BSI with CNS disease using imaging reports and define the epidemiology, characteristics, management, and associated clinical outcomes. Methods We conducted a retrospective study of inpatients (1/1/2014 to 10/31/2019) with MSSA BSI and head imaging (± 7 days of BSI). Imaging reports were categorized into probable, possible, or no CNS involvement. Charts were reviewed to assess source and metastatic sites of infection, severity of illness, and clinical course. Demographics, comorbidities, antibiotic use, and morbidity and mortality were electronically extracted from the corporate data warehouse. Primary antibiotic treatment was defined as the antibiotic received for the highest proportion of treatment course. Results 1852 patients had MSSA BSI and a head imagining performed. 151 (8%) had probable and 56 (3%) had possible CNS involvement. Embolic disease (n=167 [87%]) was the most common type of CNS disease (136 [83%] with probable CNS disease). Overall, high severity of illness defined by ICU admission (52%), vasopressor (7%), or mechanical ventilation (15%) was observed overall and was more common with probable CNS disease. Cefazolin was the most common primary antibiotic (71 [40%]), followed by nafcillin or oxacillin (51 [29%]). 16 (31%) patients had an adverse reaction to nafcillin. 69 (33%) patients died by day 30 and 88 (43%) by day 90. Recurrent CNS infections and bacteremia by day 90 was observed in 11 (6%) and 6 (3%). Conclusion We propose a definition of MSSA bacteremia complicated by CNS disease. CNS disease with MSSA bacteremia is infrequent with the most common manifestation being embolic disease. A significant number of patients with MSSA bacteremia were treated with cefazolin despite evidence of CNS disease. Overall mortality was high. Given higher rates of adverse drug events with nafcillin or oxacillin, comparative effectiveness studies are needed to further define the role of cefazolin for MSSA bacteremia with CNS disease. Disclosures All Authors: No reported disclosures