1. What Is Creatinine Clearance?

Creatinine clearance is a measure of the kidney's ability to filter and remove creatinine from the blood. It provides a direct estimation of glomerular filtration rate (GFR) using 24-hour urine collection and plasma creatinine levels.

2. How Does The Calculator Work?

The calculator uses the standard creatinine clearance formula:

Where:

• \( U_{cr} \) — Urine creatinine concentration (mg/dL)
• \( V \) — Urine volume flow rate (mL/min)
• \( P_{cr} \) — Plasma creatinine concentration (mg/dL)

Explanation: This formula calculates the volume of plasma cleared of creatinine per minute, providing a direct measurement of kidney filtration function.

3. Importance Of Creatinine Clearance

Details: Creatinine clearance is crucial for assessing renal function, monitoring kidney disease progression, and adjusting medication dosages for drugs eliminated by the kidneys.

4. Using The Calculator

Tips: Enter urine creatinine in mg/dL, urine volume in mL/min, and plasma creatinine in mg/dL. All values must be positive numbers greater than zero for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: How is 24-hour urine volume converted to mL/min?
A: Divide the total 24-hour urine volume (in mL) by 1440 (minutes in 24 hours) to get mL/min.

Q2: What are normal creatinine clearance values?
A: Normal range is typically 90-120 mL/min for young adults, decreasing with age due to natural decline in kidney function.

Q3: Why use 24-hour urine collection?
A: 24-hour collection accounts for diurnal variations in creatinine excretion and provides a more accurate assessment than spot urine measurements.

Q4: What factors affect creatinine clearance accuracy?
A: Incomplete urine collection, muscle mass variations, certain medications, and dietary protein intake can affect results.

Q5: When is creatinine clearance preferred over eGFR?
A: In patients with extreme body sizes, amputees, rapidly changing kidney function, or when precise drug dosing is critical.