UREA NITROGEN, URINE, 24 HOUR

Test Code

UUN (OE), UUN24 (LAB)

CPT Codes
84540

Preferred Specimen

24 Hour Urine Container without preservative

Patient Preparation
Discard first morning urine on day of collection and record time. Collect all urine voided during the next 24 hours. Refrigerate the urine during entire colleciton. See 24 hour urine collection instructions link below.

Minimum Volume

1 mL aliquot (20 mL aliquot)

Instructions

Mix the specimen well and measure the 24 Hour volume (RECORD THE TOTAL VOLUME)
Pour off 20 mL of urine into a separate plastic screw-cap container
Refrigerate if not tested immediately

Transport Temperature

Refrigerate

Specimen Stability

2-8°C up to 5 days

Methodology
Colorimetric

Setup Schedule

M, T, W, Th, F, Sa, Su

As received; STAT testing is available

Clinical Significance

Urea excreted in the urine is the primary method of nitrogen elimination; therefore, this test provides an approximate evaluation of nitrogen balance. Conditions associated with increased urine urea nitrogen are hyperthyroidism, high protein diets and post-operative states. Decreased levels are associated with convalescence, liver disease, toxemia and advanced renal disease.

Performing Laboratory
Alverno Central Lab

Additional Information
24 Hour Urine Collection Instructions

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.