Table 1.

Histopathological grading scale for degree of inflammation

GradeCondition of:
1Subepithelial cell inflammatory infiltration (focal and multifocal)Focal inflammation (cellular infiltration and/or edema in the pelvis)
2Edema and subepithelial inflammatory cell infiltration (diffuse)Focal inflammation (more severe) from pelvis to medulla, with and without moderate edema
3Marked subepithelial inflammatory cells with necrosis and neutrophils in and on bladder mucosal epitheliumMultifocal inflammation and cells from pelvis to medulla
4Inflammatory cell infiltrate extends into muscle in addition to criteria for grade 3Extensive segmental inflammation and necrosis evident from pelvis to cortex
5Loss of surface epithelium (necrosis with full-thickness inflammatory cell infiltration)Diffuse tissue necrosis and inflammatory cell infiltration extending from pelvis to cortex