bih.button.backtotop.text
BROWSE BY TEST NAME
%
1
2
3
5
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
Clear
 
Test Code:
090-20-0030-01

Order Name:
BUN

 
Useful For:
Screening test for evaluation of kidney function
 
Methodology:
Urease
 
AliasesName:
Blood Urea Nitrogen
 
 
 
Test Code:
090-20-0030-01

Order Name:
BUN

 
Collection Specimen Or Container:
Blood/ Plain blood (Red top) 6 mL, 1 tube
 
Specimen Testing Type:
Serum, minimum volume 0.5 mL
 
Sub Mission Container:
Plastic vial
 
Rejection Criteria:
Hemolysis: 4+ reject
 
 
Specimen Stabillity:
Specimen Type Temperature Time
Serum Refrigerated, 2oC to 8oC 7 days
Frozen, -20oC 12 months
 
 
 
Test Code:
090-20-0030-01

Order Name:
BUN

 
Method detail:
Urease
 
Schedule:
Tested daily (24 hours)
 
Turnaround Time:
Collected specimen to report within 1.5 hours (90 mins)
 
Performing Location:
Chemistry, Laboratory Department Tel. 13224
 
Specimen Retention Time:
5 days
 
 
 
Test Code:
090-20-0030-01

Order Name:
BUN

 
 
Clinical Information:
Measurements obtained by this test are used in the diagnosis of certain renal and metabolic diseases. The determination of serum urea nitrogen is a widely used test for the evaluation of kidney function. The test is frequently requested in conjunction with the serum creatinine test for the differential diagnosis of prerenal (cardiac decompensation, water depletion, increased protein catabolism), renal (glomerulonephritis, chronic nephritis, polycystic kidney, nephrosclerosis, tubular necrosis), and postrenal (obstructions of the urinary tract) hyperuremia.
 
Reference Value:
7 – 21 mg/dL
 
Interpretation:
Serum blood urea nitrogen (BUN) determinations are considerably less sensitive than BUN clearance (and creatinine clearance) tests, and levels may not be abnormal until the BUN clearance has diminished to less than 50%. Clinicians frequently calculate a convenient relationship, the urea nitrogen:creatinine ratio-serum bun in mg/dL/serum creatinine in mg/dL.

For a normal individual on a normal diet, the reference interval for the ratio ranges between 12 and 20, with most individuals being between 12 and 16. Significantly lower ratios denote acute tubular necrosis, low protein intake, starvation, or severe liver disease. High ratios with normal creatinine levels may be noted with catabolic states of tissue breakdown, prerenal azotemia, high protein intake, etc. High ratios associated with high creatinine concentrations may denote either postrenal obstruction or prerenal azotemia superimposed on renal disease. Because of the variability of both the BUN and creatinine assays, the ratio is only a rough guide to the nature of the underlying abnormality. Its magnitude is not tightly regulated in health or disease and should not be considered an exact quantity.
 
Clinical Reference:
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)