1. What is BUN/Creatinine Ratio?

The BUN/Creatinine ratio is a measurement that compares the levels of blood urea nitrogen (BUN) and creatinine in the blood. It helps differentiate between various causes of kidney dysfunction and dehydration.

2. How Does the Calculator Work?

The calculator uses a simple ratio formula:

Where:

• BUN — Blood urea nitrogen in mg/dL
• Creatinine — Serum creatinine in mg/dL

3. Clinical Significance

Normal Range: Typically 10:1 to 20:1
High Ratio (>20:1): May suggest prerenal azotemia (dehydration, heart failure)
Low Ratio (<10:1): May suggest liver disease or malnutrition

4. Using the Calculator

Tips: Enter both BUN and creatinine values in mg/dL. Both values must be greater than 0 for calculation.

5. Frequently Asked Questions (FAQ)

Q1: What are normal BUN and creatinine values?
A: BUN: 7-20 mg/dL; Creatinine: 0.6-1.2 mg/dL (women), 0.7-1.3 mg/dL (men)

Q2: Why is the ratio important?
A: It helps distinguish between kidney dysfunction caused by decreased blood flow (prerenal) versus intrinsic kidney damage.

Q3: Can medications affect the ratio?
A: Yes, corticosteroids and tetracyclines can increase BUN, while a high-protein diet can also affect results.

Q4: When is this test typically ordered?
A: When kidney dysfunction is suspected or to monitor known kidney disease.

Q5: Are there limitations to this ratio?
A: The ratio should always be interpreted in clinical context as many factors can influence both BUN and creatinine levels.