Cockcroft-Gault Formula
CrCl = [(140 − age) × weight (kg)] / [72 × creatinine (mg/dL)]. Multiply by 0.85 for females. Widely used for drug dosage adjustment.
CKD-EPI 2021 Formula
The CKD-EPI 2021 formula is the most current, recommended by nephrology societies. It estimates GFR without race variable, making it more universal and accurate near normal GFR values.
CKD Stages
CKD is classified in 5 stages by GFR: Stage 1 (≥90) = normal, Stage 2 (60-89) = mild, Stage 3a (45-59) = mild-moderate, Stage 3b (30-44) = moderate-severe, Stage 4 (15-29) = severe, Stage 5 (<15) = kidney failure.
Frequently Asked Questions
Cockcroft-Gault vs CKD-EPI?
Cockcroft-Gault estimates clearance (mL/min) and depends on weight. CKD-EPI estimates GFR (mL/min/1.73m²) and is more accurate near normal values.
What is GFR used for?
GFR evaluates kidney filtration capacity. It guides CKD diagnosis and drug dosage adjustments.
When to calculate clearance?
For patients over 65, diabetics, hypertensives, or before prescribing nephrotoxic drugs.
How to convert creatinine from µmol/L to mg/dL?
Divide µmol/L by 88.4. Example: 100 µmol/L = 1.13 mg/dL.