Urea Clearance

Casandra

Casandra Test Code AR50955Version 1 (DRAFT)

Performing Lab

Lab ARUP LaboratoriesLab Test ID 2005207CPT Code 84545

Also known as: UNCL

Clinical Use

Order Test

Use

The Urea Clearance test is used to evaluate renal function by measuring the clearance of urea, a waste product of protein metabolism, from the blood by the kidneys. It provides insight into the kidney's ability to filter and excrete urea, helping to assess renal health and diagnose potential kidney disorders. The test is particularly useful in diagnosing and monitoring conditions such as acute and chronic kidney diseases, as well as glomerulonephritis and other nephropathies.

Special Instructions

Patient should refrigerate the 24-hour urine collection during the process. Both blood and urine samples need to be collected within a specified timeline to ensure accurate results. It's important to record the total urine volume and the collection time interval on the transport tube and test request form for accurate processing.

Limitations

The test may not provide accurate results in cases of fluctuating kidney function or when the collections are not performed correctly, such as incomplete urine collection or failure to refrigerate the sample. Certain medications or dietary factors could potentially influence urea levels. Random urine collections are not acceptable due to potential variability in urea excretion rates.

Test Details

New York Approved

Methodology

Automated Analyzer (Clinical Chemistry)

Biomarkers

Urea

Analyte

Urea Clearance • Concentration / Level • Quantitative (Continuous) (e.g., copies/mL, % expression)

Urine Urea Nitrogen • Concentration / Level • Quantitative (Continuous) (e.g., copies/mL, % expression)

Total Volume • Concentration / Level • Quantitative (Continuous) (e.g., copies/mL, % expression)

Hours Collected • Concentration / Level • Quantitative (Continuous) (e.g., copies/mL, % expression)

Urea, Serum • Concentration / Level • Quantitative (Continuous) (e.g., copies/mL, % expression)

LOINC Codes

Result Codes

51735-9
12967-6
19153-6
30211-7
3094-0

Result Turnaround Time

1 day

Specimen

Urine

Volume

3 mL

Minimum Volume

0.5 mL

Container

ARUP Standard Transport Tube

Collection Instructions

Collect 24-hour urine and refrigerate during collection. Transfer one 3 mL aliquot from a well-mixed 24-hour collection to an ARUP Standard Transport Tube.