Free AI MDRD GFR Calculator

The MDRD equation estimates kidney function in patients with chronic kidney disease (CKD) by adjusting serum creatinine for age, sex, and race. This calculator is critical for staging CKD, guiding treatment decisions, and predicting complications like electrolyte imbalances or cardiovascular risk.

How to Use the MDRD GFR Calculator

Follow these steps to generate a diagnostic report:

Patient Data Entry Guide

Step 1: Input Laboratory Values

1. Serum Creatinine (Scr): Enter value + unit (mg/dL or μmol/L).
   • Example: 1.2 mg/dL or 106 μmol/L

Step 2: Input Demographic Data

1. Age: Enter age in years.
   • Example: 60
2. Sex: Specify Male/Female/Other.
   • Example: Female
3. Race: Indicate if the patient is African American (Yes/No).

Step 3: Input Symptoms

1. Symptoms: Describe symptoms or clinical concerns.
   • Example: Fatigue, swelling in ankles, reduced urine output

Sample Diagnostic Report

MDRD GFR Calculation:

• Serum Creatinine: 1.4 mg/dL
• Age: 65 years | Sex: Male | Race: African American (Yes)
• Equation:eGFR=175×(Scr)−1.154×(Age)−0.203×Sex Factor×Race Factor
  • Sex Factor: 1.0 (Male)
  • Race Factor: 1.212 (African American)
  • eGFR=175×(1.4)−1.154×(65)−0.203×1.0×1.212=∗∗45mL/min/1.73m2∗∗

Interpretation:

• CKD Stage: Stage 3b (eGFR 30–44 mL/min/1.73 m²).
• Risk Implications: Increased risk for cardiovascular disease, anemia, and electrolyte imbalances.

Clinical Correlation:

• Symptoms like fatigue and ankle swelling align with reduced kidney function (fluid retention, anemia).

Recommendations:

1. Confirm CKD stage with repeat testing over 3 months.
2. Monitor blood pressure, hemoglobin, potassium, and phosphate levels.
3. Limit protein intake (0.6–0.8 g/kg/day) and sodium (<2 g/day).
4. Refer to nephrology if eGFR < 30 mL/min/1.73 m².

Key Considerations

• Unit Conversions:
  • μmol/L → mg/dL: Divide by 88.4 (e.g., 106 μmol/L = 1.2 mg/dL).
• Equation Limitations:
  • Validated for CKD patients only; less accurate in acute kidney injury (AKI) or healthy individuals.
  • Replaced by CKD-EPI equation for general use but remains relevant in CKD staging.
• Race Adjustment: Controversial; use clinical judgment if genetic ancestry is uncertain.

Equation

4-Variable MDRD GFR Formula:

eGFR (mL/min/1.73 m²)=175×(Scr (mg/dL))−1.154×(Age)−0.203×{0.7421.212​if Femaleif African American​

CKD Staging (KDIGO Guidelines)

Final Diagnosis: Combines eGFR, symptoms, and demographics to guide management (e.g., anemia workup in Stage 3b CKD with fatigue or urgent referral for eGFR < 15 mL/min/1.73 m²).