الوصف
Cystatin C is a 122-amino acid, 13-kD protein that is a member of the family of cysteine proteinase inhibitors. It is the product of a “housekeeping” gene expressed in all nucleated cells and is produced at a constant rate. Cystatin C is filtered by the glomerulus. It is not secreted, but is reabsorbed by tubular epithelial cells and subsequently catabolised so that it does not return to the blood flow. The use of serum Cystatin C to estimate glomerular filtration rate (GFR) is based on the same logic as the use of blood urea nitrogen and creatinine, but because it does not return to the bloodstream and is not secreted by renal tubules, it has been suggested to be closer to the “ideal” endogenous marker.
دواعي الإستعمال
This test is useful in the diagnosis of various renal pathologies, including primary and secondary glomerulonephritis, rheumatoid disorders, and diabetic nephropathy. Recent studies suggest that Cystatin C is an early indicator of mild renal failure. Cystatin C is reportedly more sensitive than serum creatinine for mild decreases in GFR and creatinine clearance. In addition to detecting post-transplant renal damage earlier than serum creatinine, Cystatin C has also been suggested to predict renal function recovery earlier than creatinine. In children, Cystatin C may perform better than creatinine in assessing GFR.
نوع العينة والكمية والشروط
1 ml Serum Room Temperature
إحتياطات خاصة
المعدل الطبيعي
Cys C: GFR: <1 year: 0.59 -1.97 mg/L 32-150 mg/L 1-17 years: 0.50 -1.27 mg/L 57-188 mg/L 18-49 years: 0.53 -0.95 mg/L 80-174 mg/L 50 years: 0.58 -1.05 mg/L 73-153 mg/L By Report
