1. What is the MDRD Formula?

The MDRD (Modification of Diet in Renal Disease) equation estimates glomerular filtration rate (GFR) from serum creatinine, age, sex, and race. It was developed to provide a more accurate assessment of kidney function in patients with chronic kidney disease.

2. How Does the Calculator Work?

The calculator uses the MDRD equation:

Where:

• \( Scr \) — Serum creatinine (mg/dL)
• \( Age \) — Age in years
• 0.742 — Female multiplier
• 1.212 — Black race multiplier

Explanation: The equation uses serum creatinine, age, gender, and race to estimate kidney function, with different coefficients for different demographic groups.

3. Importance of eGFR Calculation

Details: Accurate GFR estimation is crucial for diagnosing chronic kidney disease, determining disease stage, monitoring disease progression, and guiding medication dosing decisions.

4. Using the Calculator

Tips: Enter serum creatinine in mg/dL, age in years, select gender and race. All values must be valid (creatinine > 0, age between 1-120 years).

5. Frequently Asked Questions (FAQ)

Q1: What is the difference between MDRD and CKD-EPI?
A: CKD-EPI is generally more accurate at higher GFR levels (>60 mL/min/1.73m²), while MDRD may be more accurate in advanced CKD. CKD-EPI is now more widely recommended.

Q2: What are the limitations of the MDRD equation?
A: Less accurate in elderly patients, extremes of body size, pregnant women, and populations with normal or near-normal kidney function.

Q3: When was the MDRD equation developed?
A: The MDRD equation was developed in 1999 and has been widely used for CKD staging and management.

Q4: Is the MDRD equation standardized?
A: Yes, the MDRD equation uses standardized creatinine measurements and has been validated in multiple populations.

Q5: Should MDRD be used for drug dosing?
A: For precise drug dosing, especially with narrow therapeutic windows, measured GFR or more specific equations may be preferred.