BackgroundAntimicrobials are widely used in solid organ transplant recipients (SOTr). Yet, antimicrobial utilization in the transplant (TP) population is not well characterized. National Healthcare Safety Network antimicrobial use (NHSN-AU) does not provide data specific to SOTr. This study sought to describe inpatient antibiotic use among SOTr up to 1-year post-TP.MethodsA cross-sectional study was performed of all SOTr who received a TP between January 2015 to December 2016. Demographics, TP type, antibiotic use variables, hospital days, and Clostridioides difficile infection (CDI) are described. Inpatient antibiotic administration was measured for 365 days starting from date of TP surgery. Automated data generated for NHSN-AU reporting was utilized, and SOTr data was abstracted by cross-matching with the transplant database. Transplant-patient days was used as the denominator for metrics. Variables included duration of therapy (DOT), DOT/1000 patient days, antimicrobial free days (inpatient days no antimicrobials were administered), and NHSN-AU reporting targets of anti-methicillin resistant S. aureus (MRSA), broad spectrum, and high-risk CDI agents. Data was analyzed using descriptive statistics via Microsoft Excel®. ResultsA total of 530 SOTr were analyzed. Baseline characteristics are shown in Table 1. Median age was 61, male gender 64%, median Charlson Comorbidity Index was 5. Kidney TP (43%), liver TP (32%), lung (9%) and heart (8%) were most common TP types. Among these four TP types: Lung TP had the highest median DOT (13 days), DOT/1000 patient days (6.6) and ratio of DOT/total patient (1.9) (Table 2). Liver TP had the most antimicrobial free days (34%). Proportionally, anti-MRSA agents use was highest in thoracic TP (lung/heart), broad-spectrum agent use was common in all but kidney TPs, and high-risk CDI agents use was highest among kidney TP (Table 3). A total of 34 SOTr had CDI, 76% in kidney/liver TPs. Table 1. Antimicrobial usage and SOT - ID Week 2021 Table 2. Antimicrobial usage and SOT - ID Week 2021 Table 3. Antimicrobial usage and SOT - ID Week 2021ConclusionOur study provides preliminary and important data of inpatient antibiotic utilization specifically in SOTr, generated using automated NHSN-AU data cross-matched to transplant database. These metrics can be utilized to promote antimicrobial stewardship efforts directed to specific TP types. Disclosures Rachel Kenney, PharmD, Medtronic, Inc. (Other Financial or Material Support, spouse is an employee and shareholder)