Cystatin C

Cystatin C is a protein produced by all cells in your body at a relatively constant rate and filtered by the kidneys into urine. Measuring urine cystatin C levels helps assess kidney filtration function. Unlike creatinine, cystatin C is less affected by muscle mass and certain medications, making it a valuable marker for detecting early kidney disease or monitoring kidney function changes. This test is often used alongside other kidney markers to provide a more complete picture of kidney health.