Chronic kidney disease or a condition in which kidney function decreases based on abnormal renal filtration rate. In the initial stages, there are usually no abnormal symptoms. You don’t know if you don’t have the blood test and urinalysis. Two types of tests can be used: Cystatin C and Creatinine. This article will explain why Cystatin C is better.
What is Cystatin C ?
Cystatin C is a protein in the blood that is filtered by the kidneys and serves as an indicator of kidney function. It is found in both tissues and various body fluids.
Functions of Cystatin C :
It is responsible for protecting connective tissue from damage by enzymes that operate inside cells and plays a role in preventing bacterial and viral infections.
How is Cystatin C related to the screening of chronic kidney disease?
In normal people, Cystatin C is released into the bloodstream in constant quantities and filtered through the glomerulus, never returning to the bloodstream. If the ability of the kidneys to function and the filtration of the glomerulus decreases, the level of Cystatin C in the blood increases, or it can be said that kidney function deteriorates.
Comparison of Cystatin C and Creatinine tests
For the assessment of early-stage kidney disease, Cystatin C is a better marker than Creatinine, with accuracy and sensitivity in clinical use for kidney function testing, and is more related to eGFR (estimated Glomerular Filtration Rate) than Creatinine because Creatinine has interference factors from muscle mass, water intake, certain foods high in protein, supplements, and certain medications that affect Creatinine values, and reduce the accuracy of the calculated eGFR values in assessing chronic kidney disease. Cystatin C values have fewer interference factors, such as obesity, chronic inflammation, steroid use, and thyroid disease.
The creatinine test is not sensitive enough to monitor kidney disease in the early stages, and abnormalities can be detected when the kidney function has been damaged by 50%, but the Cystatin C test can be detected faster than the creatinine value.
For accurate and specific assessment of kidney function, both Cystatin C and Creatinin eGFR should be tested together.
Laboratory Examination
It can be detected from the blood, without abstaining from water and food.
Recommended programs for kidney disease screening:
- Kidney Function Test (BUN)
- Renal Function Test (Creatinine + eGFR)
- Uric acid level test
- Cystatin C
