1. What is the MDRD Creatinine Clearance Calculator?

The MDRD (Modification of Diet in Renal Disease) Creatinine Clearance Calculator adjusts the estimated glomerular filtration rate (eGFR) based on body surface area (BSA) to provide a more personalized creatinine clearance estimation.

2. How Does the Calculator Work?

The calculator uses the MDRD adjustment formula:

Where:

• \( eGFR \) — Estimated glomerular filtration rate (mL/min/1.73m²)
• \( BSA \) — Body surface area (m²)
• 1.73 — Standard body surface area reference value

Explanation: This adjustment accounts for individual body size differences, providing a more accurate creatinine clearance estimation for medication dosing and renal function assessment.

3. Importance of Adjusted CrCl Calculation

Details: Adjusted creatinine clearance is crucial for accurate medication dosing, particularly for drugs that are renally excreted, and for personalized assessment of renal function in clinical practice.

4. Using the Calculator

Tips: Enter eGFR in mL/min/1.73m² and BSA in m². Both values must be valid positive numbers for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: Why adjust eGFR with BSA?
A: eGFR is standardized to 1.73m² BSA. Adjusting for actual BSA provides individualized renal function assessment.

Q2: How is BSA typically calculated?
A: BSA is commonly calculated using formulas like DuBois, Mosteller, or Haycock based on height and weight measurements.

Q3: When is adjusted CrCl particularly important?
A: Essential for precise drug dosing in patients with extreme body sizes (very small or very large) and for medications with narrow therapeutic windows.

Q4: Are there limitations to this adjustment?
A: The adjustment assumes linear proportionality between BSA and GFR, which may not hold true in all physiological conditions.

Q5: Should adjusted CrCl replace standard eGFR reporting?
A: Both values have clinical utility - standardized eGFR for population comparisons and adjusted CrCl for individualized treatment decisions.