Comparison of patient hospital length of stay pre and post implementation of the CLINITEK AUWi System from Siemens to screen out negative urine samples intended for culture: A retrospective cohort study

Abstract

Objective: To determine the impact of using the CLINITEK AUWi System to screen out negative urine samples intended for culture on patient length of stay and culture results at a community teaching hospital. Design and methods: We used a retrospective cohort design to compare length of stay for patients admitted before and after implementation of the CLINITEK AUWi System to screen urine samples prior to culture. Before implementation, all urine samples were sent to an external laboratory for culture. After implementation, urine samples were screened first, and culture was only performed for those samples above the 325 bacteria/µl cutoff. We assessed patient length of stay before and after implementation. Results: Our study included 306 samples (168 pre, 138 post). In the post-implementation group, 60.9% of cultures were screened negative and not sent for culture, resulting in fewer negative culture results (74.4% vs 40.7%, p<0.001). Median overall length of stay was reduced from 176 h (IQR 234.75) to 128.5 h (IQR 192.5, p=0.018), a decrease of over 40 h. Differences in length of stay were especially pronounced among female patients, patients aged 80 or over, and patients with urinary tract disorder in the diagnostic differential. Conclusions: Use of the CLINITEK AUWi System reduced the need for culture by screening out 60.9% of samples as negative, and was associated with a shorter mean length of stay. Our findings have implications for cost savings, due to both the reduced length of stay and the reduced need for culture. Keywords: Urine culture screen, Bacteriuria, Flow cytometry, Length of stay, Sysmex UF-1000i, Urinary sediment examination, Urinary tract infection, Automated urine sediment analyzer