Test Code 1013(test includes BUN and Creatinine)
Test Details
BUN/Creatinine Ratio
BUN/Creatinine Ratio is a calculation using blood (serum) urea nitrogen (BUN) and creatinine.
Methodology
BUN/Creatinine ratio is calculated as follows:
BUN divided by Creatinine
Patient Preparation
None
Preferred Specimen
1.0 mL serum (0.5 mL minimum) collected in serum separator tube (SST/Tiger Top)
Alternate Specimen
1.0 mL EDTA plasma (0.5 mL minimum) collected in plasma separator tube (Pearl Top)
Transport Temperature
Refrigerated (ship on frozen cold packs)
Stability
Refrigerated: 7 days
Lab Values
BUN/Creatinine Ratio
- Normal: ≤23
- Increased Risk: >23
Clinical Significance
BUN/Creatinine Ratio
- An elevated BUN/Creatinine ratio may be present with dehydration or in acute or chronic renal disease, reduced renal perfusion, or urinary tract obstruction.
- Increased urea production may also elevate the ratio.
Treatment Options
BUN/Creatinine Ratio
- Identify etiology of elevated BUN and creatinine with physical assessment and additional diagnostic tests as indicated.
- Treatment is based on etiology of elevation.
