Cystatin C

Cystatin C is a protein that is produced by the cells in your body. When kidneys are working well, they keep the level of cystatin C in your blood just right. If the level of cystatin C in your blood is too high, it may mean that your kidneys are not working well.

A blood test for cystatin C can help your healthcare provider find your GFR (glomerular filtration rate). Your GFR number helps your healthcare provider know how well your kidneys are working.

A cystatin C blood test can be helpful if:

  • A previous test for kidney function was inconclusive or needs to be confirmed. In this instance, your healthcare provider may give you cystatin C test to confirm whether or not you have kidney disease.
  • You are overweight, elderly or have lots of muscle (such as a body builder). Cystatin C-based estimates for GFR are believed to be less influenced by muscle mass or diet than creatinine-based estimates.
  • Sample of blood serum
  • We perform the test in 24 hours from sampling