Chronic glomerulonephritis is best considered a pool of endstage glomerular disease fed by a number of streams of specific types of glomerulonephritis.
Figure : Primary glomerular diseases leading to chronic glomerulonephritis (GN). The thickness of the arrows reflects the approximate proportion of patients in each group who progress to chronic glomerulonephritis: poststreptococcal (1% to 2%); rapidly progressive (crescentic) (90%), membranous (30% to 50%), focal glomerulosclerosis (50% to 80%), membranoproliferative glomerulonephritis (50%), IgA nephropathy (30% to 50%).
- The kidneys are symmetrically contracted and have diffusely granular, cortical surfaces.
- On section, the cortex is thinned, and there is an increase in peripelvic fat. There eventually ensure hyaline obliteration of glomeruli, transforming them into acellular eosinophilic masses.
- The hyaline represents a combination of trapped plasma proteins, increased mesangial matrix, basement membrane like material and collagen.
- Because hypertension is an accompaniment of chronic glomerulonephritis, arterial and arteriolar sclerosis may be conspicuous.
- Marked atrophy of associated tubules, irregular interstitial fibrosis, an mononuclear leukocytic infiltration of the interstitium also occurs.