Today, clinical laboratories customarily calculate eGFR using either the
MDRD or CKD-EPI equation whenever a serum creatinine is obtained.
Abbreviations GFR --glomerular filtration rate cysC --cystatin C CKD --chronic kidney disease ESRD --end stage renal disease CV --cardiovascular DTPA --diethylenetriamine pentaacetate
MDRD --Modicifaction of Diet in Renal Disease CKD-EPI --The Chronic Kidney Disease Epidemiology Collaboration [Cre.sub.equ] --formulas for calculating the GFR from serum concentrations of creatinine [CysC.sub.equ] --formulas for calculating the GFR from serum concentrations of cystatin C PENIA --particle enhanced nephelometric immunoassay PETIA --particle enhanced turbidimetric immunoassay PE --preeclamspia DM --diabetes mellitus DN --diabetic nephropathy CCIMT --intimo-medial complex of the common carotid artery Review article
Reasons to use the
MDRD or CKD-EPI study equation to estimate GFR (5):
Caption: FIGURE 1: Scatter plots of the isotopic glomerular filtration rate (GFR) versus 1/creatinine, creatinine clearance, 1/cystatin C, Cockcroft-Gault formula,
MDRD equations with 4 and 6 variables, CKD-EPI-Cr, CKD-EPI-CysC, and CKD-EPI-Cr-CysC.
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MDRD estimates GFR based on age, race, sex, and serum creatinine.
Using the 4-parameter
MDRD equation, we compared the eGFR calculated from creatinine values obtained by various field methods between 2006 and 2011.
The two main formulas for the calculation of GFR are the Cockroft-Gault and
MDRD (Modification of Diet in Renal Disease), although currently the most widely used is a modification of the simplified
MDRD formula (sMDRD or simplified
MDRD).
The
MDRD study equation was developed in the USA using data from patients with CKD and there have been several versions of the equation.
Glomerular filtration rate was calculated using the Modification of Renal Diet (
MDRD) equation.
Estimated glomerular filtration rate (eGFR) was calculated by two formulas; Cockcroft-Gault (CG) and Modification of Diet in Renal Disease Study (
MDRD) (12, 13).
This equation is more accurate in determining kidney function than is the Modification of Diet in Renal Disease (
MDRD) study equation, said Dr.