Test Code BUN.1 BLOOD UREA NITROGEN
Methodology
Colorimetric
Useful as a screening test for the evaluation of kidney function. This test is frequently requested along with serum creatinine; simultaneous determination of these 2 compounds appears to aid in the differential diagnosis of prerenal, renal, and postrenal hyperuremia.
Specimen Requirements
Submit only 1 of the following specimens:
Preferred:
Serum
Serum Gel Tube
Container/Tube: Serum gel tube(s)
Specimen Volume: 1 mL (minimum volume: 0.5 mL) of
serum
Collection Instructions: Spin down within 4 hours of draw.
Note: Label specimen appropriately (serum).
Alternate:
Serum
Plain, Red-Top Tube
Container/Tube:
Plain, red-top tube(s)
Specimen Volume: 1 mL (minimum volume: 0.5 mL) of
serum
Collection Instructions: Spin down within 4 hours of draw.
Note: Label specimen appropriately (serum).
Plasma
Container/Tube: Green-top (lithium heparin) tube(s) or EDTA Plasma
Specimen Volume: 1 mL (minimum volume: 0.5 mL) of plasma
Collection Instructions: Spin down within 4 hours of draw.
Note: Label specimen appropriately (plasma).
Day(s) Test Set Up
Monday through Sunday
Reference Values
<1 year: 2-19 mg/dL
≥1 year: 7-21 mg/dL
Performing Laboratory
Logan Health Medical Center-Chemistry
Test Classification and CPT Coding
84520
Specimen Transport Temperature
Refrigerate