Urea Nitrogen, Urine 24 Hour

Message

Performing Lab: Regions

Test Code

3601

Alias/See Also

Sunquest: UUN24

CPT Codes
84540

Preferred Specimen

0.2 mL of a 24-hour urine collection

Minimum Volume

0.1 mL

Instructions

Preserve 24 hour urine collection with refrigeration.

Consult Urine Collection/Processing Information for acceptable preservatives

Transport Container

Sterile Container

Transport Temperature

Refrigerated

Specimen Stability

Refrigerated: 7 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Unacceptable preservatives

Methodology
Colorimetric

Setup Schedule

Daily

Report Available

Same Day

Reference Range

12.0 - 20.0 g/24 hour

Clinical Significance

Urea nitrogen is the end product of breakdown of proteins in the body. In individuals with normal kidney and liver functions, urea is excreted via urine. By testing for urine urea nitrogen, clinicians can assess one's nitrogen balance. Calculating nitrogen balance is a useful tool in assessing adequacy of protein provision in clinical setting. Among the renal causes of increased levels are acute glomerulonephritis, chronic nephritis, polycystic kidney, nephrosclerosis, and tubular necrosis. Any type of obstruction of the urinary tract is a postrenal cause for elevated urea nitrogen levels.

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.