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Urea Nitrogen, 24 hour (or timed) urine

Item Value
Approval req'd? Yes, if testing is requested between midnight and 8:00 AM.
Available Stat? No
Test code UNU
Test group Urea
Performed by Parnassus & Mission Bay Chemistry
In House Availability Test available 7 days per week from 8:00 AM to midnight only.
Method Enzymatic conductivity, kinetic (urease)
Collection Instructions Refrigerate the container during the period of the collection.

Note that the minimum acceptable time period for a 'timed' collection is 6 hours.

Results of collections of less than 24 hour duration will be adjusted to reflect a '24 hour collection'. The limited time of collection as well as the need to adjust the values to be comparable to the '24 hour' normal ranges will inherently affect the accuracy of the results.
Container type 24 hour urine collection container

Click here for Urine Preservative Requirements
Amount to Collect Entire urine output for collection period
Sample type Timed urine collection
Preferred volume 1 mL urine
Min. Volume 0.2 mL urine
UCSF Rejection Criteria Container not refrigerated during collection.
Units g/D
Normal range 10-20 g/D
Synonyms UUN
Stability Refrigerated 2 days
Turn around times Same or next day
Additional information To convert mg/dL to mmol/L (SI units) multiply by 0.357.

Output varies with diet.

Results of collections of less than 24 hour duration will be adjusted to reflect a '24 hour collection'. The limited time of collection as well as the need to adjust the values to be comparable to the '24 hour' normal ranges will inherently affect the accuracy of the results.
Last Updated 1/28/2015 3:34:30 PM
Entry Number 966
Lab Procedure Link Click here for Procedure
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