Egfr Calculator Kidney Health Australia

The estimated glomerular filtration rate (eGFR) is a key measure of kidney function. This calculator uses the CKD-EPI formula to estimate your eGFR based on your serum creatinine level, age, sex, and race. Understanding your eGFR can help you monitor kidney health and identify potential issues early.

What is eGFR?

The estimated glomerular filtration rate (eGFR) measures how well your kidneys are filtering blood. It's expressed in milliliters per minute per 1.73 square meters (mL/min/1.73m²). The eGFR helps assess kidney function and detect early signs of kidney disease.

Key Points

Normal eGFR range: 90 mL/min/1.73m² or higher
Mildly decreased: 60-89 mL/min/1.73m²
Moderately decreased: 30-59 mL/min/1.73m²
Severely decreased: 15-29 mL/min/1.73m²
Kidney failure: Less than 15 mL/min/1.73m²

Kidney function declines with age, so the eGFR formula accounts for age and other factors to provide a more accurate assessment. Regular monitoring of eGFR can help detect kidney problems early when treatment is most effective.

How to Use This Calculator

To calculate your eGFR:

Enter your serum creatinine level in micromoles per liter (µmol/L)
Select your sex (male or female)
Enter your age in years
Select your race (Black or non-Black)
Click "Calculate" to see your estimated eGFR

Example Calculation

For a 50-year-old Black female with a serum creatinine of 80 µmol/L:

eGFR = 141 × (min(SCr/κ, 1)^α) × (max(SCr/κ, 1)^-1.209) × 0.993^Age × 1.018 × 1.159

Where κ = 0.7 for Black females, α = -0.329

The calculator will display your eGFR result along with an interpretation of what this means for your kidney health.

Formula and Assumptions

The calculator uses the CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) formula for estimating eGFR:

CKD-EPI Formula

For males:

eGFR = 141 × (min(SCr/κ, 1)^α) × (max(SCr/κ, 1)^-1.209) × 0.993^Age × 1.018

For females:

eGFR = 141 × (min(SCr/κ, 1)^α) × (max(SCr/κ, 1)^-1.209) × 0.993^Age × 1.018 × 1.159

Where:

SCr = Serum creatinine level (µmol/L)
κ = 0.9 for non-Black males, 0.7 for Black males, 0.7 for non-Black females, 0.7 for Black females
α = -0.411 for non-Black males, -0.329 for Black males, -0.329 for non-Black females, -0.329 for Black females
Age = Age in years

This formula accounts for age, sex, and race to provide a more accurate estimate of kidney function. The calculator uses these standard coefficients based on clinical research.

Interpreting Your Results

Your eGFR result falls into one of these categories:

eGFR Range	Kidney Function	Recommendation
≥90 mL/min/1.73m²	Normal	Continue regular monitoring
60-89 mL/min/1.73m²	Mildly decreased	Monitor with healthcare provider
30-59 mL/min/1.73m²	Moderately decreased	Consult a nephrologist
15-29 mL/min/1.73m²	Severely decreased	Seek immediate medical attention
<15 mL/min/1.73m²	Kidney failure	Urgent medical evaluation required

If your eGFR is below normal, it may indicate kidney damage. Regular monitoring and medical advice are important for managing kidney health.

Important Note

This calculator provides an estimate. For precise diagnosis, consult with a healthcare professional who can perform additional tests and consider your complete medical history.

Frequently Asked Questions

What is the difference between GFR and eGFR?

GFR (glomerular filtration rate) is the actual measurement of how well your kidneys filter blood. eGFR (estimated GFR) is a calculation based on factors like serum creatinine, age, sex, and race. eGFR provides an estimate when GFR can't be directly measured.

How often should I check my eGFR?

If you're healthy, you may not need frequent checks. However, if you have risk factors for kidney disease (diabetes, high blood pressure, etc.), your doctor may recommend regular monitoring, typically every 1-2 years.

Can diet affect my eGFR results?

Yes, diet can influence kidney function. A balanced diet with controlled sodium, potassium, and phosphorus intake can help maintain healthy kidney function. Always consult with a healthcare provider for personalized dietary advice.

Is eGFR the same worldwide?

No, eGFR formulas can vary by region. The CKD-EPI formula used in this calculator is commonly used in Australia and other parts of the world. However, some countries may use different formulas based on local research.