1. What is the CKD-EPI Creatinine Equation?

The CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) equation estimates glomerular filtration rate (GFR) from serum creatinine, age, and sex. This specific variant provides an accurate assessment of kidney function using updated coefficients.

2. How Does the Calculator Work?

The calculator uses the CKD-EPI equation:

Where:

• \( Scr \) — Serum creatinine (mg/dL)
• \( \kappa \) — 0.7 (female) or 0.9 (male)
• \( \alpha \) — -0.241 (female) or -0.302 (male)
• \( age \) — Age in years
• 1.012 — Female multiplier

Explanation: The equation accounts for non-linear relationship between creatinine and GFR, with different coefficients for males and females.

3. Importance of GFR Calculation

Details: Accurate GFR estimation is essential for evaluating kidney function, detecting early kidney disease, and monitoring treatment effectiveness.

4. Using the Calculator

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

5. Frequently Asked Questions (FAQ)

Q1: What is the difference between this equation and standard CKD-EPI?
A: This version uses updated coefficients (142, -1.200, 0.9938) for potentially improved accuracy in specific populations.

Q2: What are normal GFR values?
A: Normal GFR is generally ≥90 mL/min/1.73m². Values below 60 for 3+ months may indicate chronic kidney disease.

Q3: When is the best time to measure creatinine?
A: Morning fasting samples are preferred, but random samples can be used. Avoid testing after high-protein meals or intense exercise.

Q4: Are there limitations to this calculation?
A: The equation may be less accurate in elderly patients, those with extreme body composition, or rapidly changing kidney function.

Q5: Can this calculation be used for medication dosing?
A: While useful for screening, measured GFR may be needed for precise medication dosing in critical situations.