eGFR Calculator (CKD-EPI)

About eGFR Calculator (CKD-EPI)

This eGFR calculator uses the renal function CKD-EPI equation to estimate the rate of glomerular filtration (given patient age, gender, race and serum creatinine level).

The CKD-EPI equation

This is the recommended method for laboratory estimation of GFR based on serum creatinine, patient age, gender and race. CKD-EPI comes from Chronic kidney disease epidemiology collaboration.

By providing eGFR, the method helps assess renal function and can be used for patients over 18.

eGFR = 141 X min(Cr/κ,1)α X (max(Cr/κ,1)^-1.209) X (0.993^Age) X 1.018 [if female] X 1.159 [if black]

Where:

■ Cr- is serum creatinine in mg/dL;

■ k is 0.7 for women, 0.9 for men;

■ α is –329 for women and –0.411 for men.

eGFR levels and CKD stages

Chronic kidney disease is the name given to a series of conditions in which the kidneys gradually lose their function. According to the National Kidney Foundation, the two main causes of CKD are diabetes and high blood pressure.

Normal glomerular filtration rate should be 100 mL/min/1.73m2, but any value above 90 is considered to be normal function.

However, in case there are other signs of chronic disease, despite a theoretically healthy eGFR, the patient is likely to be in stage 1.

You can find the five stages of chronic kidney disease explained in the table below:
Stage eGFR (mL/min/1.73m2) Kidney function Other information
1 >90 Normal Some signs of kidney disease or damage like protein or blood in urine, kidney inflammation
2 60-89 Mildly reduced Some signs pointing to kidney disease, similar to stage 1;
If the eGFR coincides with stage 2 but there are no signs of kidney damage then there is no CKD.
3A 45-59 Moderately reduced Signs of kidney disease
3B 30-44 Possible in elderly people without specific CKD
4 15-29 Severely reduced Close to end stage renal failure
5 <15 Very severe or end stage kidney failure Established renal failure