Kidney Biomarker

Legacy kidney biomarkers include serum creatinine (sCr), blood urea nitrogen (BUN), urinary albumin/protein and volume excretion. However, sCr or BUN cannot distinguish injury from hemodynamic changes in the kidney that lead to appropriate changes in glomerular filtration rate (GFR), particularly when the changes are acute. Furthermore, sCr or BUN cannot change quickly enough with injury since individuals with normal renal function have a functional reserve that is brought into play in response to nephron injury. Other nephrons increase their function so that sCr and BUN may not move out of the "normal range" until there is a great deal of injury and potentially irreversible loss of nephrons. Thus GFR, whether measured by sCr or by more direct methods such as iohexol clearance, is a measure of function of the kidney which is clearly important but which may not move in sync with injury under all circumstances.

Kidney Biomarkers