How high is too high for cystatin C?

Under normal circumstances, the reference range for cystatin C is 0.6–2.5 mg/L; values above this range are considered elevated. A detailed explanation is as follows:

Cystatin C is a protein filtered by the kidneys and excreted in urine, commonly used as an indicator to assess kidney function. Normally, the level of cystatin C in plasma remains relatively stable, with a reference range of 0.6–2.5 mg/L. However, when kidney function is impaired, cystatin C levels rise above the normal range. It should be noted that determining whether elevated cystatin C levels are related to kidney disease usually requires comprehensive evaluation along with other clinical indicators and test results.

If there are any concerns regarding cystatin C levels, it is recommended to consult a physician promptly for professional advice.