Creatinine Clearance Cockcroft and Gault Equation (mL/min) & CKD-EPI Creatinine Equation 2021 (eGFR mL/min/1.73m)

CrCl= [(140−Age) × Weight (kg)​ / (72 × Serum Creatinine (mg/dL))] × 0.85 [if female]

Reasoning for CrCl Selection

• If ABW > 120% of IBW → Use AdjBW
• If ABW < IBW → Use ABW
• If ABW ≈ IBW → Use IBW

Special Considerations:
– Some facilities may have their own guidelines for adjusting parameters (e.g., elderly patients). Ensure you review and apply your institution’s policy accordingly.

eGFRcr = 142 × min(Scr/κ, 1)ᵅ × max(Scr/κ, 1)⁻¹⋅²⁰⁰ × 0.9938ᴬᵍᵉ × 1.012 [if female]

• Scr = Serum Creatinine (SCr) (mg/dL & µmol/L)
• κ (Kappa) = 0.7 for females 0.9 for males
• α (Alpha): = -0.241 for females-0.302 for males
• min(Scr/κ, 1) selects the smaller value between (Scr/κ) and 1
• max(Scr/κ, 1) selects the larger value between (Scr/κ) and 1

Body Mass Index (BMI):
BMI = weight (kg) / [height (m)] ² or BMI = 703 x weight (lbs) / [height (in)] ²

Ideal Body Weight (IBW):
Males: 50kg + 2.3kg * (for each inch over 5 feet)
Females: 45.5 + 2.3kg * (for each inch over 5 feet)

Adjusted Body Weight (AdjBW):
AdjBW = Ideal Body Weight + 0.4 (Actual Body Weight – Ideal Body Weight)

Body Surface Area (BSA)
BSA = √[ (Height (cm) x Weight(kg) / 3600]

Cockcroft DW, Gault MH. Prediction of creatinine clearance from serum creatinine. Nephron. 1976;16(1):31-41. doi: 10.1159/000180580. PMID: 1244564.

Inker LA, Eneanya ND, Coresh J, Tighiouart H, Wang D, Sang Y, Crews DC, Doria A, Estrella MM, Froissart M, Grams ME, Greene T, Grubb A, Gudnason V, Gutiérrez OM, Kalil R, Karger AB, Mauer M, Navis G, Nelson RG, Poggio ED, Rodby R, Rossing P, Rule AD, Selvin E, Seegmiller JC, Shlipak MG, Torres VE, Yang W, Ballew SH, Couture SJ, Powe NR, Levey AS; Chronic Kidney Disease Epidemiology Collaboration. New Creatinine- and Cystatin C-Based Equations to Estimate GFR without Race. N Engl J Med. 2021 Nov 4;385(19):1737-1749. doi: 10.1056/NEJMoa2102953. Epub 2021 Sep 23. PMID: 34554658; PMCID: PMC8822996.

Buchkremer F, Segerer S. The 2009 and 2021 CKD-EPI Equations: A Graphical Analysis of the Effect of Refitting GFR Estimating Equations Without a Race Coefficient. Kidney Med. 2022 Mar 11;4(5):100448. doi: 10.1016/j.xkme.2022.100448. PMID: 35607637; PMCID: PMC9123604.Supplemental Files Available: Link to PMC Article & Supplements

Mosteller RD. Simplified calculation of body-surface area. N Engl J Med. 1987 Oct 22;317(17):1098. doi: 10.1056/NEJM198710223171717. PMID: 3657876.