Pathogenesis of edema with glomerulonephritis
Pathogenetically different three types of edema. developing at different kidney damage .
1. Edema in acute and chronic kidney failure. The main mechanism of their development is hydrostatic (hypervolemic). Reduction of the glomerular filtration rate, characteristic of renal failure, leads to a delay in sodium and water in the body (positive water balance) and, consequently, to hypervolemia. The latter, being the cause of the increase in hydrostatic pressure in the capillaries, causes the development of edema by the mechanism of Starling.
2. Nephrotic edema. The main mechanism of their development is oncotic (hypoproteinemic). Violations of the glomerular filter during nephrosis cause massive proteinuria, as a result of which hypoproteinemia develops and oncotic blood pressure falls. This, in turn, by the mechanism of Starling causes the passage of water from the vessels into the tissues - edema develops.
3. Nephritic edema. Develop with acute and chronic glomerulonephritis. The pathogenesis of these edema is complex and includes the following mechanisms:
a) inflammation of the glomeruli -> stagnation of blood in the vesselskidney -> hypoxia of the juxtaglomerular apparatus -> activation of the renin-angiotensin system -> secretion of aldosterone -> sodium retention in the body and increased osmotic blood pressure -> secretion of the antidiuretic hormone -> water retention -> hypervolemia -> edema;
b) inflammation of the glomeruli -> impaired renal circulation -> decreased glomerular filtration rate -> sodium and water retention in the body -> hypervolemia -> edema;
c) inflammation of the glomeruli -> increased permeability of the renal filter -> proteinuria -> hypoproteinemia -> edema.