Before this chapter

glomerulonephritis: an inflammation of the glomerulus that may involve an increase in the number of endogenous cells or in their extracytoplasmic matrix, or infiltration with exogenous cells, or both

• "Focal" is taken to mean less than 70% of glomeruli affected. (in a given histological section)

• "Diffuse": 70% or more glomeruli affected.

• "Segmental": a portion or lobule the glomerular tuft showing obliteration of capillary lumens by disease.

• "Global": all portion of a given glomerular tuft capillary obliteration.