LAUSR

C. difficile remains the single most common pathogen among healthcare-associated infections. We conducted a multi-center, prospective study using on-site, near real-time root cause analyses to identify opportunities for reducing hospital-onset C. difficile infection rates (HO-CID). This prospective cohort study enrolled inpatients with HO-CDI admitted to one of 20 participating hospitals in the southeastern United States from July 2019 to June 2020. For each HO-CDI case, mini root cause analyses were conducted by on-site physicians, infection preventionists, or stewardship pharmacists to assess appropriateness of C. difficile testing and inpatient antibiotic use from the 30 days preceding HO-CDI diagnosis. The cohort captured 554 total HO-CDI cases and 956 antibiotic use events. 147 (26.5%) of HO-CDI cases were adjudicated as likely inappropriate and a further 51 (9.2%) as potentially inappropriate. Among inappropriately tested cases, 103 (52.0%) had received either laxatives or tube feeds in the preceding 48 hours. 132 (13.8%) of antibiotic use events were identified as potentially inappropriate. Among potentially inappropriate antibiotic use events, 40 (30.3%) received unnecessarily broad-spectrum antibiotics, 20 (15.2%) lacked a confirmed infectious diagnosis, and 4 (3.0%) received a longer than guideline-recommended duration. Risk of inappropriate antibiotic use varied by infection type, with treatment of urinary tract infection being associated with the highest risk of inappropriate antibiotic use (table 1). Table 1: Relative Risk of Inappropriate Antibiotic Use by Indication Mini root cause analyses may be a helpful tool for identifying -specific opportunities to reduce HO-CDI rates. We found a high rate of inappropriate testing, usually related to alternative causes for diarrhea such as laxative receipt or tube feeds. While rates of inappropriate antibiotic use were lower than has been reported elsewhere, the majority of opportunities for improvement related to overly broad-spectrum coverage. Urinary tract infections were most strongly associated with inappropriate antibiotic use preceding HO-CDI. All Authors: No reported disclosures