Vol 7, No 3 (2006): Practical Diabetology
Review article
Published online: 2006-05-22
Proteinuria and progression of chronic kidney disease. Does the kind of excreted protein affect progression of renal disease?
Diabetologia Praktyczna 2006;7(3):194-199.
Abstract
Massive proteinuria in the case of glomerular disease
is an effect of deragements in filtration barrier
and disorders of proteins resorption (concerning
mainly low-molecular proteins) by the epithelial cells
of proximal tubules. The barrier’s permeability is
selective and depends on the size of the molecules
in the plasma and their charge. The growing intensity
of disorders of structural integrity of glomerular capillary walls is accompanied not only by the
increased amount of proteins; proteins of larger
molecule radius and larger molecular weight appear
in the tubular lumens; the selectivity of the filtration
barrier is disturbed. Initially, selective proteinuria
appears, with albumin (molecular weight - 69 kD,
molecular radius - 36 Å) as the dominant protein.
With increasing damage to the glomeruli, a growing
amount of proteins with greater molecular weight
gets through the capillary walls and the amount of,
e.g., IgG (molecular weight - 150 kD, molecular
radius - 55 Å) in the tubular lumen increases rapidly.
It has been believed for a long time that the
sort of excreted proteins can be a better indicator
of the damage to the glomerular capillary walls than
the total protein excreted with urine; it can also affect
the response to treatment and prognostication
for patients with proteinuria. We would like to
discuss the problem in this paper.
Keywords: primary renal diseasesproteinuriasort of excreted proteininterstitial damage