Nephrology Question 5 Instructor

Using the Cockcroft-Gault and MDRD formulas, calculate the estimated glomerular filtration rate (eGFR) in the following patient:

A 70 year old Caucasian male with serum creatinine 250 micromol/L and weight of 70kg. BUN and albumin are unavailable.

In which populations and at what GFRs do these estimation formula perform poorly?

Cockcroft Gault creatinine clearance is 24.1 ml/min. MDRD estimated GFR is 23.7 ml/min.

The Cochcroft-Gault formula is:

Creatinine clearance
= (140-age[years]) * weight [kg]
(72 X serum creatinine)

For women, multiply by 0.85.

The abbreviated MRDRD formula:

GFR = 186.3 * (SCR)-1.154 * (age in years)-0.203 * 1.212 (if patient is black) * 0.742 (if female)

The CKD-EPI has been developed to be a more accurate tool to estimate GFR. It performs particularly well when GFR is relatively preserved.

MDRD and CKD-EPI eGFR can be calculated at:

iPhone, iPad, BlackBerry and Android users can get an eGFR calculator at

These formula may not be reliable in pregnant women, children, or patients with normal renal function, obesity,or prior amputations.


Cockcroft DW and Gault MH. Prediction of creatinine clearance from serum creatinine. Nephron 1976; 16(1): 31-41.

Levey et al. A more accurate method to estimate glomerular filtration rate from serum creatinine: a new prediction equation. Ann Intern Med. 1999; 130(6):461-70.

Levey AS, Stevens LA, Schmid CH, Zhang YL, Castro AF 3rd, Feldman HI, Kusek JW, Eggers P, Van Lente F, Greene T, Coresh J; CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration). A New Equation to Estimate Glomerular Filtration Rate. Ann Intern Med 150(9):604-12. (2009)

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