UREAU24

Urea Nitrogen, Urine 24-Hour

24-hour urine, Clean containner with preservative
Preservative -  can be selected as list below:

1. 20 mL of 6N HCL (Preferred) or
2. 10 mL of 25% HCl or
3. non preservative if order with Protein (U-24 hrs) or Microalbumin ( U-24 hrs)

Note:

• Please keep in refrigerated (2-8°C) during collection and transportation
• 24-hours volume is required.

24-hour urine,minimum volume 10 mL

Clean container

Wrong preservative type will be reject.

Specimen Type	Temperature	Time
24 hours urine	Refrigerated, 2oC to 8oC	7 days
	Frozen, -20oC	1 month

UREAU24

Urea Nitrogen, Urine 24-Hour

Urease

Tested daily (24 hours)

Collected specimen to report within 1.5 hours (90 mins)
 

Chemistry, Laboratory Department Tel. 13224

7 days

UREAU24

Urea Nitrogen, Urine 24-Hour

Urea is a low molecular weight substance (Mol Wt=60) that is freely filtered by glomeruli and the majority is excreted into the urine, although variable amounts are reabsorbed along the nephron. It is the major end product of protein metabolism in humans and other mammals. Approximately 50% of urinary solute excretion and 90% to 95% of total nitrogen excretion is composed of urea under normal conditions. Factors that tend to increase urea excretion include increases in glomerular filtration rate, increased dietary protein intake, protein catabolic conditions, and water diuretic states. Factors that reduce urea excretion include low protein intake and conditions which result in low urine output (eg, dehydration). Urea excretion is a useful marker of protein metabolism.

In oliguric patients with a rising creatinine a fractional excretion of urea <35% is consistent with a prerenal cause, while values >35% are more consistent with acute kidney injury.(2) The fractional excretion of sodium is also used for this purpose, but may be more affected by diuretics. Therefore, the fractional excretion of urea may be particularly useful for patients receiving diuretics.

12 – 20 g/day

Because multiple factors (glomerular filtration rate, dietary protein intake, protein catabolic rate, hydration state, etc.) can independently affect the urinary excretion of urea, all of these factors must be taken into account when interpreting the results.

1. Manufacturer’s reagent package insert, Architect ® Urea Nitrogen, Abbott Laboratories Diagnostics Division, Aboott Park, IL 600064, USA. November 2015
2. http://www.mayomedicallaboratories.com (Retrieved: 01 Jan 2019)