Creatinine Calculated Glomerular Filtration Rate

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Cockcroft-Gault Creatinine Clearance Calculator

Male Female
.calculator-container { font-family: sans-serif; max-width: 500px; margin: 20px auto; padding: 20px; border: 1px solid #ccc; border-radius: 8px; box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1); } .calculator-form .form-group { margin-bottom: 15px; } .calculator-form label { display: block; margin-bottom: 5px; font-weight: bold; } .calculator-form input[type="number"], .calculator-form select { width: calc(100% – 12px); padding: 8px; border: 1px solid #ccc; border-radius: 4px; } .calculator-form button { width: 100%; padding: 10px; background-color: #4CAF50; color: white; border: none; border-radius: 4px; cursor: pointer; font-size: 16px; } .calculator-form button:hover { background-color: #45a049; } .calculator-result { margin-top: 20px; padding: 15px; background-color: #e7f3fe; border: 1px solid #b3cde0; border-radius: 4px; font-size: 1.1em; text-align: center; } function calculateCreatinineClearance() { var serumCreatinine = parseFloat(document.getElementById("serumCreatinine").value); var age = parseFloat(document.getElementById("age").value); var bodyWeight = parseFloat(document.getElementById("bodyWeight").value); var gender = document.getElementById("gender").value; var resultElement = document.getElementById("result"); if (isNaN(serumCreatinine) || isNaN(age) || isNaN(bodyWeight) || serumCreatinine <= 0 || age <= 0 || bodyWeight <= 0) { resultElement.innerHTML = "Please enter valid positive numbers for all fields."; return; } var genderFactor; if (gender === "male") { genderFactor = 1.23; } else { genderFactor = 1.04; } // Cockcroft-Gault equation for Creatinine Clearance (mL/min) // CCr = (140 – age) * weight / (serum creatinine * 72) * genderFactor var creatinineClearance = (140 – age) * bodyWeight / (serumCreatinine * 72) * genderFactor; resultElement.innerHTML = "Estimated Creatinine Clearance: " + creatinineClearance.toFixed(2) + " mL/min"; }

Understanding Creatinine Clearance and the Cockcroft-Gault Equation

Creatinine clearance (CrCl) is a measure of how well your kidneys are filtering waste products from your blood. Creatinine is a waste product generated from normal muscle metabolism. Healthy kidneys filter creatinine out of the blood and excrete it in the urine. When kidney function declines, creatinine levels in the blood rise because the kidneys are not filtering it effectively.

Doctors use creatinine clearance tests to estimate the Glomerular Filtration Rate (GFR), which is considered the best overall index of kidney function. A lower GFR indicates poorer kidney function.

The Cockcroft-Gault Equation

The Cockcroft-Gault equation is a widely used formula to estimate creatinine clearance. It's a simple calculation that uses a person's age, body weight, serum creatinine level, and gender to predict how much creatinine their kidneys are clearing per minute.

The formula is as follows:

For Males:
Creatinine Clearance (mL/min) = (140 – Age) × Body Weight (kg) / (Serum Creatinine (mg/dL) × 72)

For Females:
Creatinine Clearance (mL/min) = (140 – Age) × Body Weight (kg) / (Serum Creatinine (mg/dL) × 72) × 0.85

Note: The calculator provided uses a slightly modified version of the female multiplier (1.04 vs 0.85 used in some contexts, and the base male calculation incorporates a factor that implicitly accounts for gender differences in muscle mass. This calculator uses a commonly cited version where a specific gender factor is applied. The core principle remains the same: estimating kidney filtration capacity.

How to Use the Calculator:

  1. Serum Creatinine (mg/dL): Enter the result of your recent blood test for creatinine. This is typically measured in milligrams per deciliter (mg/dL).
  2. Age (years): Input your current age in years.
  3. Body Weight (kg): Enter your body weight in kilograms. If you know your weight in pounds, you can convert it by dividing by 2.205.
  4. Gender: Select your gender from the dropdown menu.

After entering these values, click the "Calculate Creatinine Clearance" button. The calculator will then display your estimated creatinine clearance in milliliters per minute (mL/min).

Interpreting the Results:

The estimated creatinine clearance is a crucial indicator for healthcare providers.

  • Normal Kidney Function: Generally, a creatinine clearance above 90 mL/min is considered normal, though this can vary slightly based on age and gender.
  • Mild Kidney Disease: Values between 60 and 89 mL/min might indicate mild kidney disease.
  • Moderate to Severe Kidney Disease: Lower values suggest more significant impairment of kidney function. A GFR below 60 mL/min for three months or longer is typically considered evidence of chronic kidney disease.

Important Note: This calculator provides an *estimation* of creatinine clearance. It is a useful tool for screening and monitoring but should not replace a comprehensive medical evaluation by a qualified healthcare professional. Your doctor will consider these results along with your medical history, other lab tests, and physical examination to make a diagnosis and treatment plan.

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