Abstract: SA-PO931
Changes in the Composition of Urine Using Urinalysis and Automated Microscopy over 6 Hours at Room Temperature
Session Information
- Pathology and Lab Medicine - 2
October 26, 2024 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Pathology and Lab Medicine
- 1800 Pathology and Lab Medicine
Authors
- Parikh, Pranav C., Gilman School, Baltimore, Maryland, United States
- D Souza, Serena, Johns Hopkins University, Baltimore, Maryland, United States
- Obeid, Wassim, Johns Hopkins University, Baltimore, Maryland, United States
Background
Urinalysis (UA) is a commonly performed test for the diagnosis and prognosis of kidney disease in hospitalized patients. UA involves examining the chemical composition of the urine as well as microscopy to examine the cells and casts. In clinical settings, there is a frequent delay of several hours to perform UA after sample collection. The purpose of this study is to investigate the changes in urine composition over set time intervals in order to confirm the reliability of UA when there are delays in performing the tests.
Methods
We obtained 15 mL of urine from the Foley catheters of five ICU patients. We utilized the state-of-the-art IDEXX Sedivue machine to perform urine microscopy and the Siemens CLINTEK Status+ Urine Analyzer to perform the dipstick tests. We performed both microscopy and dipstick tests at 0, 1, 2, 4, and 6 hours. The samples were left at room temperature between measurements. We altogether tested 30 individual components in the urine. We calculated the %CV for each component by taking 4 repeated measurements at one time period for multiple samples.
Results
After calculating the %CV for each component, we analyzed the trend for each constituent over the 6-hour period. If the percent change over the six-hour interval was significantly more than the %CV, we determined time to have an influence on the results. Significant changes were seen in bacteria (BACc), as the levels increased, RBC and mucus (MUC) where the levels decreased, and crystals (CRY and CRYu) levels were determined inconclusive due to fluctuations in the results (see figure). All other components were found to remain unchanged.
Conclusion
The majority of the components were unchanged suggesting that UA results for these could be helpful even if the processing of the sample is delayed in clinical settings. The changes in the levels of bacteria and blood could lead to an incorrect clinical diagnosis. Additionally, changes in some components are highly variable and cannot be compensated for with certainty.
Funding
- NIDDK Support