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