A patient may progress over time. As azotemia develops and progresses, the magnitude of proteinuria may decrease. After immune complexes lodge, complement is fixed and activated resulting in chemotaxis of inflammatory cells, and release of lysosomal proteases which lead to glomerular damage. Platelets adhere to the damaged endothelium and activate the coagulation cascade leading to deposition of fibrin in the glomerulus. Cell mediated immunity also plays role in immune injury to the glomerulus.
Proliferative changes are active lesions, and potentially can be reversed.
Proliferation of parietal epithelial cells is called cresents and in humans is usually irreversible. Similar information about cresent formation in dogs and cats is not known. Membranous GN is a thickening of the basement membrane. Membranoproliferative is a combination of proliferative and membranous. Sclerosis is an end stage appearance and is irreversible.