997. Burden of Inappropriate Urine Culture Collection and Processing on the Environment

Abstract

Abstract Background Healthcare is the second-most energy-intensive commercial sector in the United States. Clinical laboratories make up a large portion of that energy use and contribute significantly to waste production (7, 8, 9, 10). We aimed to estimate the environmental impact of urine cultures and suggest inappropriate culturing as a target for diagnostic stewardship and waste mitigation. Methods The total number of urine cultures performed by our facility’s microbiology laboratory was gathered. The plastic components, including bacterial culture plates, urine sample collection cups, and biohazard bags, were weighed. Results Between 3/07-03/13/21, 533 urine cultures were processed by our facility. Since the number of bacterial culture plates varies between samples, we calculated a range from 2 cell-culture plates (clean catch sample) to 4 cell-culture plates (in-and-out catheterization sample), with an additional 1-2 plates per isolate for susceptibility testing. This yielded a range of 3-6 total plates (30g for bacterial culture plates, 120g for susceptibility plates) used per processed urine culture. Each sample also requires a collection cup (27.2g or 19.1g) and a biohazard bag (4.1g) yielding a range of 95 - 192kg of plastic waste over the study period. Assuming this week represents an average week, our projected annual waste is between 6.5 to 12 tons for urine culture collection and testing. Conclusion In this single-center pilot study, urine cultures produced an estimated 6.5 to 12 tons of plastic waste annually. Prior studies suggest that 58%-68% of urine cultures are not clinically indicated (2, 3). This includes up to 35% of emergency department urine cultures being done in the context of a negative urinalysis, 20% of urine cultures sent without a urinalysis, and a urine culture contamination rate of at least 5% (4). While the effects of inappropriate urine cultures on length of hospital stay, antibiotic stewardship, and healthcare costs have been investigated, the subsequent impact on the environment has not been well studied (5). Although this study was limited by its reliance on estimated numbers, the sizable impact on healthcare’s net waste production suggests that further quantifying inappropriate culturing and how to alleviate it is an important area for further investigation. Disclosures All Authors: No reported disclosures.