Feb 1, 2018




Clinical Hub,Tools & Resources,UWHC Lab Test Directory,Chemistry

Urea Nitrogen, Urine, 24 Hour

Urea Nitrogen, Urine, 24 Hour (HCUUREA) Chemistry Lab Test

Name: Urea Nitrogen, Urine, 24 Hour

Test Name: Urea Nitrogen, Urine, 24 Hour

Health Link Test Code: HCUUREA

LIS Test Code: UUREA

CPT Code(s): 84540

Methodology: Urease

Days Performed: Daily, 24 hours.

In-Lab Turnaround Time: 4 hours.

Stat In-Lab Turnaround Time: 1 hour.

Specimen: 24 hour timed urine

Collection Container: 24 hour urine container

Collection Instructions:

Collect 24 hour urine. No preservative required. For timed urine collections, collect all urine in container provided. Add "Refrigerate" sticker to 24-hour container.


For 24-hour urine test the collection period must be within 22-26 hours. Collection period starts after first void of the period. It is very important to refrigerate specimen during and after the collection. Indicate the date and time collection started and date and time collection finished. If questions about collection process or container does not have instructions attached, call (608) 263-7060 for assistance.


Patient instructions available at www.uwhealth.org. Search for 24-hour urine collection or HF#4339.

Collection Volume: Entire collection

Stability Ambient:

2 days

Stability Refridgerated:

7 days

Stability Frozen:

1 month

Sample Analyzed: Urine aliquot

Testing Volume: 1 mL

Pediatric Testing Volume: 0.4 mL

Outreach Specimen Processing:

Mix urine well and note volume and period. Transport 50 mL aliquot on coolant pack to the laboratory along with volume and period information.

Specimen Transport:

Transport entire specimen to the laboratory at close of collection. Transport with coolant pack if coming from clinic location.


0 days and up: 12-20 g/24 hours


Results calculated only for collections of 22-26 hours.

Interpretation Type: Reference Interval

Additional Information:

Urine urea is usually used as an indicator of renal function. For nutritional assessment of nitrogen balance see Total Nitrogen, Urine.