What is considered a low GFR (glomerular filtration rate) reading?
- GFR < 60 ml/min is low and a concern, and may indicate chronic kidney disease (CKD)
- GFR <45 ml/min is a problem, and is CKD.
What is GFR, and what is it used for?
It is a blood test/number that reflects kidney function; the higher the GFR, the better the kidney function, the better.
The GFR is used to:
- Diagnose CKD
- Monitor – changes in kidney function over time
- Decide – whether you need dialysis or a kidney transplant.
What is a normal GFR?
A normal GFR number is 90-120 ml/min (in adults); according to something called the CKD/GFR classification. This ‘places’ a GFR level in a stage of CKD. Stage 1 is best and Stage 5 the worst.
How does GFR determine the stage of CKD?
This is summarised in this table.
CKD/GFR classification
Note. But, the big but. These number ranges (and what we have said is a ‘normal’ GFR’) are so neat, they are clearly made up (wrong) – as are all the CKD stages. But it is the simple table that doctors and nurses use to guide investigation and treatment.
Other resource
Here is more information on the problems with GFR on our sister CKD Explained website.
