Blood Test Creatinine and Calculated Glomerular Filtration Rate

Calculated Glomerular Filtration Rate (eGFR) Calculator

Male Female
African American Other

Estimated Glomerular Filtration Rate (eGFR):

Understanding Creatinine and eGFR

Your kidneys are vital organs responsible for filtering waste products and excess fluid from your blood. The Glomerular Filtration Rate (GFR) is a measure of how well your kidneys are performing this essential task. It represents the volume of fluid that is filtered by the glomeruli (tiny filtering units in the kidneys) per unit of time.

A direct measurement of GFR is complex and often impractical in routine clinical settings. Therefore, doctors often estimate it using a formula based on your serum creatinine level, age, sex, and race. This estimated GFR is known as eGFR.

Serum Creatinine:

Creatinine is a waste product produced by your muscles as they break down a compound called creatine. Healthy kidneys filter creatinine out of your blood and excrete it in your urine. A higher level of creatinine in your blood can indicate that your kidneys are not filtering efficiently, suggesting a decline in kidney function.

The CKD-EPI Formula:

The most commonly used formula for calculating eGFR is the CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) equation. This calculator uses a version of this formula. The equation takes into account:

  • Serum Creatinine: The measured level of creatinine in your blood (in mg/dL).
  • Age: Your age in years. Kidney function naturally declines with age.
  • Sex: Biological sex influences muscle mass, which affects creatinine production.
  • Race: Historically, race has been included in some eGFR calculations due to perceived differences in muscle mass. However, the inclusion of race in eGFR calculations is a subject of ongoing debate and evolving clinical practice. Many current guidelines recommend using race-neutral formulas. This calculator provides an option for African American race as per the original CKD-EPI formula, but it's crucial to discuss the implications with your healthcare provider.

Interpreting Your eGFR:

Your eGFR value is reported in milliliters per minute per 1.73 square meters of body surface area (mL/min/1.73 m²). Here's a general interpretation:

  • eGFR ≥ 90: Normal kidney function, though other factors might still be of concern.
  • eGFR 60-89: Mildly decreased kidney function. This may be normal for some individuals, especially if the decline is stable and there are no other signs of kidney damage.
  • eGFR 30-59: Moderately decreased kidney function. This stage warrants further investigation and management.
  • eGFR 15-29: Severely decreased kidney function.
  • eGFR < 15: Kidney failure. Dialysis or a kidney transplant may be needed.

Disclaimer: This calculator is for informational purposes only and is not a substitute for professional medical advice. Always consult with your doctor or a qualified healthcare provider for any questions you may have regarding your medical condition or test results. They can interpret your eGFR in the context of your overall health and medical history.

function calculateEGFR() { var creatinine = parseFloat(document.getElementById("creatinine").value); var age = parseInt(document.getElementById("age").value); var gender = document.getElementById("gender").value; var race = document.getElementById("race").value; var egfr = 0; // Input validation if (isNaN(creatinine) || creatinine <= 0 || isNaN(age) || age = 90) { interpretation = "Normal kidney function or mildly reduced."; } else if (egfr >= 60) { interpretation = "Mildly to moderately reduced kidney function."; } else if (egfr >= 30) { interpretation = "Moderately to severely reduced kidney function."; } else if (egfr >= 15) { interpretation = "Severely reduced kidney function (kidney failure)."; } else { interpretation = "Kidney failure."; } document.getElementById("egfrValue").innerHTML = egfr + " mL/min/1.73 m²"; document.getElementById("egfrInterpretation").innerHTML = "Interpretation: " + interpretation; } .calculator-container { font-family: sans-serif; max-width: 800px; margin: 20px auto; padding: 20px; border: 1px solid #ddd; border-radius: 8px; background-color: #f9f9f9; } .calculator-inputs { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 15px; margin-bottom: 20px; } .form-group { display: flex; flex-direction: column; } .form-group label { margin-bottom: 5px; font-weight: bold; color: #555; } .form-group input[type="number"], .form-group select { padding: 10px; border: 1px solid #ccc; border-radius: 4px; font-size: 16px; } button { padding: 12px 20px; background-color: #007bff; color: white; border: none; border-radius: 4px; cursor: pointer; font-size: 16px; transition: background-color 0.3s ease; } button:hover { background-color: #0056b3; } .calculator-result { background-color: #e9ecef; padding: 15px; border-radius: 4px; margin-top: 20px; text-align: center; } #egfrValue { font-size: 24px; font-weight: bold; color: #007bff; margin-bottom: 10px; } #egfrInterpretation { font-size: 16px; color: #333; } .calculator-explanation { margin-top: 30px; padding-top: 20px; border-top: 1px solid #eee; color: #444; line-height: 1.6; } .calculator-explanation h3, .calculator-explanation h4 { color: #333; margin-bottom: 10px; } .calculator-explanation ul { margin-left: 20px; margin-bottom: 15px; } .calculator-explanation li { margin-bottom: 8px; } /* Responsive adjustments */ @media (max-width: 600px) { .calculator-inputs { grid-template-columns: 1fr; } .calculator-container { margin: 10px; padding: 15px; } }

Leave a Comment