Blood Urea Nitrogen (BUN)
A.k.a. Urea Nitrogen
Based on an enzymatic reaction where urea is hydrolyzed by urease yielding ammonia and carbon dioxide. The reaction results in reducing two molecules of NADH to NAD+, which is directly proportional to the amount of BUN present in the initial sample.
A quantitative determination of urea nitrogen from human serum that is used for the diagnosis of certain renal and metabolic conditions.
Specimen Collection and Preparation
Serum or plasma sample in the following tubes:
Preferred Specimen: One Gold-top OR red top SST tube. (Minimum Whole Blood: 4.0 mL)
Also acceptable: One Lithium OR Sodium Heparin tube OR one Lavender-top EDTA tube. (Minimum Whole Blood: 3.0 mL)
Specimen Storage and Stability
If analysis is delayed, the sample should be refrigerated or frozen.
Room Temperature: 24 hours
Refrigerated (2–8°C): 7 days
Frozen (-20°C or below): 60 days
Insufficient sample volume
Sample not stored at proper temperature
Frozen whole blood
Severely lipemic specimens
Specimen labeled incorrectly or not labeled
Monday – Sunday, 16 hours a day
Result available within 24 hours of receipt in laboratory
NOTE: Specimens are refrigerated (2-8°) for 7 days before disposal
Vibra Health Laboratory
1307- A, Allen Dr Troy, MI 48083