All iLive content is medically reviewed or fact checked to ensure as much factual accuracy as possible.
We have strict sourcing guidelines and only link to reputable media sites, academic research institutions and, whenever possible, medically peer reviewed studies. Note that the numbers in parentheses ([1], [2], etc.) are clickable links to these studies.
If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please select it and press Ctrl + Enter.
Serum creatinine
Medical expert of the article
Last reviewed: 05.07.2025
Creatinine is the end product of creatine breakdown, which plays an important role in the energy metabolism of muscle and other tissues. Creatine is synthesized mainly in the liver, from where it enters muscle tissue with the bloodstream. Here, creatine, phosphorylated, turns into creatine phosphate. Creatine phosphate is a macroergic compound and participates in the transfer of energy in the cell between mitochondria and myofibrils. The concentration of creatinine in the blood depends on its formation and excretion. Creatinine formation directly depends on the state of muscle mass. Creatinine is excreted by the kidneys through glomerular filtration, but, unlike urea, is not reabsorbed, which has found application in laboratory diagnostics (Reberg-Tareev test).
The concentration of creatinine in the blood of healthy people is a fairly constant value and depends little on nutrition and other extrarenal factors.
Determination of serum creatinine concentration is widely used in diagnostics of kidney diseases. Creatinine is less dependent on the level of catabolism, is not reabsorbed in the kidneys, and therefore reflects the degree of impairment of the excretory and filtration functions of the kidneys to a greater extent. A decrease in creatinine content in the blood has no diagnostic value.
Reference values (norm) of creatinine concentration in blood serum
Serum creatinine concentration |
||
Age |
µmol/l |
Mg/dl |
Newborns |
27-88 |
0.3-1.0 |
Children under 1 year |
18-35 |
0.2-0.4 |
Children from 1 year to 12 years |
27-62 |
0.3-0.7 |
Teenagers |
44-88 |
0.5-1.0 |
Adults: |
||
Men |
62-132 |
0.7-1.4 |
Women |
44-97 |
0.5-1.1 |
[ 1 ], [ 2 ], [ 3 ], [ 4 ], [ 5 ], [ 6 ], [ 7 ], [ 8 ], [ 9 ]