Creatinine clearance: standard values
Creatinine clearance indicates how quickly the kidneys can excrete urinary substances – using creatinine as an example. Urinary substances are all substances that the body has to excrete via the urine. The clearance can be used to estimate the filtration rate of the renal glomeruli (glomerular filtration rate, GFR).
The creatinine clearance can be calculated from the measured values for creatinine in the urine and blood. The urine is collected over several hours for the measurement. A urine collection over 24 hours is the most meaningful.
Creatinine clearance can also be calculated from the creatinine value of the blood plasma using the Cockcroft and Gault formula. It is particularly accurate as it also takes into account the patient’s age and body weight.
|
Age |
Creatinine clearance (in ml/min x 1.73 m2 body surface area) |
|
1st to 2nd week of life |
25 – 35 |
|
3rd week to 2nd month |
25 – 55 |
|
3rd to 12th month |
35 – 80 |
|
older children |
> 90 |
|
approx. 25 years |
Women: 70 – 110, men: 95 -140 |
|
approx. 50 years |
Women: 50 – 100, men: 70 – 115 |
|
approx. 75 years |
Women: 35 – 60, men: 50 – 80 |
Creatinine clearance vs. creatinine: Which makes more sense?
Creatinine clearance, on the other hand, is more sensitive: it can indicate even mild renal dysfunction, which is a decisive advantage over creatinine measurement.
When is creatinine clearance low?
Creatinine clearance or the glomerular filtration rate (GFR) decreases in various kidney diseases. These include, for example
- Disturbance of the renal blood flow (e.g. due to a narrowing of the renal vessels)
- Glomerulonephritis (inflammation of the renal corpuscles, which usually affects both kidneys)
- Diabetic kidney disease (diabetic nephropathy)
- Nephrosclerosis
In addition, tumors, stones or inflammation in the urinary tract can also reduce creatinine clearance.
When is creatinine clearance increased?
Creatinine clearance is increased both during pregnancy and in the early stages of diabetes mellitus.