My labs came back showing creatinine 0.8, no protein in my urine yet it showed my egfr as 73. I am a 54 Caucasian female and was wondering why my GFR shows 84 when I use an online gfr calculator. Why does my labs (blood work) show it much lower?

The online calculator calculates the estimated glomerular filtration rate (eGFR) in units that include your body size and is adjusted to a body surface area (BSA) of 1.73 meters squared.  The number can be changed by either including your body surface area or not including your body surface area.  It is also possible that the laboratory is using a different equation, such as the Cockcroft-Gault equation to calculate the creatinine clearance.  There are a number of different ways to estimate the eGFR.  Please see our web site at:


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