Question

Serum cystatin C as a marker of kidney function, its role in diagnosis, prognosis, and detection of renal impairments, in addition include in you reports the pros and cons of cystatin C as a marker of kidney function

Answer 1

Serum Cystatin C is a protein that is produced by the cells in your body. When kidneys are works well, the level of cystatin C in the blood right. If the level of cystatin C in the blood gets too high, it may means that the kidneys are not working well. A blood test for cystatin C can help to find your GFR (glomerular filtration rate). GFR number helps to estimate about the kidney working.

serum cystatin C is considered as an endogenous marker of GFR. This protease inhibitor with a low molecular weight is produced at a constant rate by all nucleated cells. It is freely filtered across the glomerular membrane and reabsorbed and metabolized in the proximal tubule. In the opposite of serum creatinine, serum cystatin C does not depend on muscle mass, sex, and age. For medical purposes, serum cystatin C could be a better indicator of GFR.

Advantage of serum cystatin C has higher diagnostic accuracy. Serum cystatin C is a new endogenous marker of renal function and is believed to be superior to serum creatinine concentration as an indicator of renal function. It is protease inhibitor produced by nucleated cells at a constant rate and is freely filtered through glomerular membrane.

Disadvantage of serum cystatin is non-creatinine chromogens are present in serum that can't be found in urine. Thus, cystatin concentration is overestimated in serum, and the calculated clearance is underestimated (for 10–20%). Serum cystatin is also insensitive for detecting small decreases in GFR because of a non-linear relationship between serum concentration and GFR.