New approach to evaluation of proteinuric states

Abstract

The use of immunonephelometric methods for measuring specific urinary proteins was evaluated. Using a nephelometer to detect light scattering (angle, 31°), we measured some proteins immunonephelometrically in serum and aliquots of 24-h urines from 50 apparently health children ages 2-17 years. The mean urinary excretion rate (mg/24 h) and the range of values was: for albumin 5.5 (range, 0-13.3) for transferrin 0.5 (0-1.9), for IgG 3.3 (0-12), and for α2-macroglobulin 0.6 (0-2.3). Direct comparison of the values for pathological urines with those for a reference population may offer more meaningful information concerning the integrity of the glomerular basement membrane than is provided by protein selectivity indices, and measuring a plasma protein such as albumin in urine may better define pathological proteinuria.