Creatinine endogenous subsatance the most widely and traditionally
Creatinine 근육에서 생성되는 endogenous subsatance the most widely and traditionally used laboratory test to assess glomerular function and to identify renal disease 사구체에서 여과된 후 세뇨관에서 재흡수 되지 않으므로 GFR 측정법으로 흔 히 사용 also well known to be an insensitive marker that is influenced by numerous factors muscle mass physical activity gender and age The dependency of the serum Cr level on age and muscle mass makes it difficult to use this marker to measure renal function, particularly in children
To compensate for the variations in Cr production Cr clearance (CCr) has been adapted to estimate the glomerular filtration rate (GFR). However, substantial tubular excretion of Cr could also influence CCr. 측정법 오랫동안 사용되어 온 Jaffe reaction은 Hb, bil 등에 의한 interference가 문제 이를 개선한 enzymatic method로 대체되고 있음(우리병원도).
Cystatin C As a result of these limitations in using Cr, research has been aimed at identifying a more sensitive marker of impaired renal function. Serum cystatin C (Cys. C) has been proposed as a novel marker for estimating the renal function. Cys. C an inhibitor of lysosomal cystein proteinases a 121 -amino-acid, a non-glycated 13 -kilodalton basic protein produced at a constant rate in all nucleated cells produced by all nucleated cells multiple biological functions such as immune modulation and control of proteolysis
In contrast to Cr, Cys. C is not secreted by tubules even in cases with reduced GFR It is almost exclusively eliminated from circulation by glomerular filtration. Moreover, it is less influenced by muscle mass, gender or age than is Cr. Therefore, it is known to be a more superior marker than Cr for assessing glomerular function, especially in pediatric patients. Since Cys. C does not depend much on muscle mass, it has an important advantage over Cr in the pediatric group. Moreover, because its reference values are independent of age, Cys. C is currently being used as a test of choice to assess renal function in pediatric patients. Cys. C levels might be influenced by factors other than GFR, such as inflammation or drugs.
Neutrophil Gelatinase-Associated Lipocalin (NGAL) Kidney 의 Tn. I also known as human neutrophil lipocalin, lipocalin-2, siderocalin, 24 p 3, or LCN 2 small molecule of almost 25 kd superfamily of proteins called lipocalins This family includes several proteins, such as a 1 -microglobulin, retinolbinding protein 4, prostaglandin D synthase, and nitrophorines. NGAL is covalently bound to gelatinase from human neutrophils and generally expressed at very low concentrations in several human tissues, including kidney, trachea, lungs, stomach, and colon.
abundantly accumulated in the blood, urine, and renal proximal and distal tubules in acute renal failure of humans renal ischemia (sepsis, hypovolemia, and heart failure) nephrotoxin (antibiotics, cisplatin, bisphonate, nonsteroidal antiinflammatory drugs, radiocontrast, and hemoglobinuria) kidney-parenchymal damage (glomerulonephrits, minimal change disease, focal segmental glomerulosclerosis, and diabetic nephropathy), hemolyticuremic syndrome and posttransplant rejection as extremely early markers of acute kidney disease serum creatinine level or glomerular filtration rate is a marker for functional nephron numbers, whereas serum, urinary, or renal Ngal level indicates the extent of active lesion in the kidney. NGAL is a very unique protein endowed with iron-carrying activity and diagnostic and therapeutic utilities for renal failure.
Forest (kidney) is composed of trees (nephrons). Both models (a) and (b) have 60% viable trees (shown in green) and 40% of trees are burnt down (shown in gray, corresponding to sclerosis of glomeruli, and atrophy of tubules). However, model (a) has much stronger fire (shown in red, that is ongoing nephron damage) than model (b). We propose that serum creatinine level or glomerular filtration rate is a marker for functional nephron numbers (green trees), whereas serum, urinary, or renal Ngal level indicates the extent of active lesion in the kidney (red fire in Mori the forest). et al. Neutrophil gelatinase-associated lipocalin as the real-time indicator of active kidney damage. Kidney Int 2007; 71: 967 -970.
- Slides: 10