Estimating glomerular filtration rate.

摘要

Glomerular filtration is an effective indicator of kidney function. Blood, plasma or serum creatinine and urine albumin and creatinine are the most common laboratory tests used to assess glomerular function. The parameters of most physiologic interest are the glomerular filtration rate (GFR) and the albumin excretion rate (AER) both of which are difficult to derive from the corresponding laboratory measurements. GFR measured as clearance of creatinine and the excretion rate of albumin require 24 h urine collection which is inconvenient for patients and consequently poorly executed. Furthermore, creatinine has limitations as a filtration marker due to variable rates of production from muscle metabolism and secretion by the proximal tubules. Soares et al., in this issue provide an excellent review of GFR measurement and prediction equations, and urine albumin measurement (1). The Laboratory Working Group of the National Kidney Disease Education Program (NKDEP, USA) has published recommendations on both topics (2, 3).