Cystatin C


5 mL blood in lithium heparin or plain tube.



Reference Interval:

1-18 years: 0.5-1.3 mg/L

Adults: 0.5-1.0 mg/L.


Assessment of glomerular filtration rate, see Creatinine clearance.


Cystatin C can be used for the diagnosis of impaired renal function. The reciprocal of the serum cystatin C concentration has been shown in several studies to have a better correlation to GFR than serum creatinine. In addition, significant increase in serum creatinine is not detected until after the GFR has fallen by 50 percent.

Cystatin C provides a good means of evaluating renal function in paediatric patients because it declines from neonatal levels to near adult values by one year of age.


Laterza OF et al. Clin Chem 2002; 48(5): 699-707.