Understanding GFR
Glomerular Filtration Rate (GFR) is a vital test that measures how well your kidneys are filtering waste products from your blood. It's expressed in milliliters per minute per 1.73 square meters of body surface area (mL/min/1.73m²).
Why is GFR Important?
Your kidneys are responsible for filtering waste and excess fluid from your blood. The GFR test provides an estimate of this filtering capacity. A declining GFR can indicate worsening kidney disease, while a stable or improving GFR suggests that your kidneys are functioning well.
The CKD-EPI 2021 Equation
The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) 2021 equation is a widely used formula for estimating GFR based on serum creatinine levels, age, sex, and race. This equation is considered more accurate than older formulas like the Cockcroft-Gault equation.
Interpreting Your GFR Results
- Normal GFR: Typically 90 mL/min/1.73m² or higher.
- Mildly decreased GFR: 60-89 mL/min/1.73m². This may indicate early kidney damage, but other factors should be considered.
- Moderately decreased GFR: 30-59 mL/min/1.73m². This usually signifies more significant kidney disease.
- Severely decreased GFR: 15-29 mL/min/1.73m². This indicates advanced kidney disease.
- Kidney Failure: Less than 15 mL/min/1.73m². This requires immediate medical attention, often dialysis or a kidney transplant.
Disclaimer: This calculator is for informational purposes only and should not be used to diagnose or treat any medical condition. Always consult with a qualified healthcare professional for any health concerns or before making any decisions related to your health or treatment.
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function calculateGFR() {
var serumCreatinine = parseFloat(document.getElementById("serumCreatinine").value);
var age = parseInt(document.getElementById("age").value);
var gender = document.getElementById("gender").value;
var race = document.getElementById("race").value;
var gfrResultElement = document.getElementById("gfrResult");
var gfrInterpretationElement = document.getElementById("gfrInterpretation");
if (isNaN(serumCreatinine) || serumCreatinine <= 0 || isNaN(age) || age = 90) {
interpretation = "Normal kidney function or mild decrease.";
} else if (gfr >= 60) {
interpretation = "Mildly decreased GFR. Consider further evaluation for kidney damage.";
} else if (gfr >= 45) {
interpretation = "Moderately decreased GFR. Kidney disease likely present.";
} else if (gfr >= 30) {
interpretation = "Moderately to severely decreased GFR. Significant kidney disease.";
} else if (gfr >= 15) {
interpretation = "Severely decreased GFR. Advanced kidney disease.";
} else {
interpretation = "Kidney failure. Requires immediate medical attention.";
}
gfrResultElement.innerText = gfr + " mL/min/1.73m²";
gfrInterpretationElement.innerText = interpretation;
}