1035. Implementation of an Antimicrobial Stewardship Program-Led, Multifactorial Pneumonia Diagnosis and Treatment Bundle

Background Pneumonia remains a leading cause of hospitalization and accounts for significant antibiotic use. This study aims to evaluate the impact of bundled antimicrobial stewardship program (ASP) interventions, including procalcitonin and surveillance cultures, on broad-spectrum antimicrobial use in patients with suspected pneumonia. Methods This is a pre-post, quasi-experimental study conducted at Michigan Medicine. During the intervention period, an ASP member reviewed adult patients admitted to 3-floor medical services with antibiotics initiated for suspected pneumonia. The ASP member (1) recommended the use of procalcitonin when clinically appropriate, (2) used institutional guidelines to guide empiric antibiotic selection based on risk for drug-resistant pathogens, and (3) ordered a methicillin-resistant Staphylococcus aureus (MRSA) surveillance culture in patients receiving empiric anti-MRSA therapy. The primary endpoint was anti-MRSA and anti-pseudomonal (PSA) antibiotic use measured as days of therapy (DOT) per 1000 days-present on the services of interest. Antibiotic use and clinical data were extracted from an electronic database. Pneumonia diagnosis codes were used to identify the study population. Results A total of 549 patients were included: 310 in the pre-intervention (December 1/2017 - 3/31/2018) and 239 in the intervention (December 1/2018 - 3/31/2019) periods. Baseline demographics were similar between groups (Table 1). Less than 15% of patients had a microbiological diagnosis via respiratory culture in both study periods (Table 2). Respiratory cultures were ordered less commonly in the intervention period; however, the rate of culture positivity was higher (28% vs. 48%, P < 0.01). Process measures improved in the intervention period with an increase in the proportion of patients with MRSA surveillance cultures (13% vs. 39%, P < 0.01) and procalcitonin monitoring (77% vs. 83%, P = 0.07). Compared with the pre-intervention period, anti-MRSA antibiotic use decreased from 172 to 158 DOT per 1000 days-present (Δ -8%) and the use of anti-PSA antibiotics decreased from 348 to 316 DOT per 1000 days present (Δ -9%). Conclusion The implementation of an ASP-led pneumonia bundle led to reductions in anti-MRSA and anti-PSA antibiotic use. Disclosures All authors: No reported disclosures.