Urea Nitrogen, Fluid
Also known as: FL UN
Use
The Urea Nitrogen, Fluid test is used to determine the concentration of urea nitrogen in body fluids like peritoneal or ascitic fluid. This measure is important for assessing the nitrogen balance in patients and can help diagnose conditions related to fluid accumulation in body cavities, such as ascites, which may be due to heart failure, liver cirrhosis, or other pathological conditions. The test aids in the evaluation of the diffusion of urea from the blood into the fluid, providing critical data for the clinical assessment of patients with fluid retention issues.
Special Instructions
Ensure that the source of the body fluid specimen is indicated on the test request form to facilitate accurate analysis and reporting.
Limitations
This test is limited to analysis of peritoneal or ascitic fluid only. The reference intervals for this test have not been established, meaning that the interpretation of results should consider other clinical findings and relevant patient information. Specimens that are too viscous may not be aspirated by the instrument, leading to rejection or invalid results.
New York Approved
Methodology
Automated Analyzer (Clinical Chemistry)
Biomarkers
LOINC Codes
- 3093-2
Result Turnaround Time
0-1 days
Related Documents
For more information, please review the documents below
Specimen
Body Fluid
Volume
1 mL
Minimum Volume
0.2 mL
Container
ARUP Standard Transport Tube
Collection Instructions
Centrifuge to remove cellular material. Transfer 1 mL body fluid to an ARUP Standard Transport Tube. Indicate source on test request form.
Storage Instructions
Refrigerated.
Causes for Rejection
Specimen types other than those listed. Specimens too viscous to be aspirated by instrument.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 1 week |
| Refrigerated | 1 week |
| Frozen | 1 year |
Other tests from different labs that may be relevant