Testing Haris
Detail Description
"Clinical Significance
BUN/Creatinine Ratio - The BUN/Creatinine ratio is useful in the differential diagnosis of acute or chronic renal disease. Reduced renal perfusion, e.g., congestive heart failure, or recent onset of urinary tract obstruction will result in an increase in BUN/Creatinine ratio. Increased urea formation also results in an increase in the ratio, e.g., gastrointestinal bleeding, trauma, etc. When there is decreased formation of urea as seen in liver disease, there is a decrease in the BUN/Creatinine ratio. In most cases of chronic renal disease the ratio remains relatively normal.
Preferred Specimen(s)
2 mL serum
Alternative Specimen(s)
Spun SST® tube
Minimum Volume
1 mL
Transport Container
Serum Separator Tube (SST®)
Transport Temperature
Room temperature
Specimen Stability
Room temperature: 7 days
Refrigerated: 5 days
Frozen: 28 days
Reject Criteria
Plasma
Setup Schedule"
Includes
BUN/Creatinine Ratio (calculated), Urea Nitrogen (BUN), Creatinine, GFR Estimated
Methodology
See individual tests
Reference Range(s)
Bun/Creatinine Ratio 6-22 (calc)
Urea Nitrogen (BUN)
Age Male (mg/dL) Female (mg/dL)
<1 Month 4-12 3-17
1-11 Months 2-13 4-14
1-3 Years 3-12 3-14
4-19 Years 7-20 7-20
≥20 Years 7-25 7-25
Creatinine
Age Male (mg/dL) Female (mg/dL)
≤2 days 0.79-1.58 0.79-1.58
3-27 days 0.35-1.23 0.35-1.23
1 month-9 years 0.20-0.73 0.20-0.73
10-12 years 0.30-0.78 0.30-0.78
13-15 years 0.40-1.05 0.40-1.00
16-17 years 0.60-1.20 0.50-1.00
18-19 years 0.60-1.26 0.50-1.00
20-49 years 0.60-1.35 0.50-1.10
50-59 years 0.70-1.33 0.50-1.05
60-69 years 0.70-1.25 0.50-0.99
70-79 years 0.70-1.18 0.60-0.93
≥80 years 0.70-1.11 0.60-0.88For patients >49 years of age, the upper reference limit for creatinine is approximately 13% higher for people identified as African-American.
eGFR Non-African American ≥60 mL/min/1.73m2
eGFR African American ≥60 mL/min/1.73m2
Alternative Name(s)
BUN, Blood Urea Nitrogen