Table 2 Histological partial scoring, with each compartment (glomeruli, tubules, interstitium) evaluated separately

1

Glomeruli: mild deposition of PTAH-positive eosinophilic material (fibrin) and reduced number of capillaries in a few glomeruli.

Tubules: <10 % of cortical tubules collapsed or degenerated.

Interstitium: few small mononuclear cell infiltrates and/or minimal fibrosis in the cortex.

2

Glomeruli: mild/moderate fibrin deposition and reduced number of capillaries in numerous glomeruli.

Tubules: 10–25 % of cortical tubules collapsed or degenerated.

Interstitium: multifocal small mononuclear cell infiltrates and/or mild fibrosis in the cortex.

3

Glomeruli: marked fibrin deposition and reduced number of capillaries in numerous glomeruli.

Tubules: 25–50 % of cortical tubules collapsed or degenerated.

Interstitium: multifocal larger mononuclear cell infiltrates and/or moderate fibrosis in the cortex.

4

Glomeruli: marked fibrin deposition and reduced number of capillaries in numerous glomeruli; glomerulosclerosis in a few to several glomeruli.

Tubules: 50–75 % of cortical tubules collapsed or degenerated; numerous dilated tubules.

Interstitium: multifocal larger mononuclear cell infiltrates and/or moderate fibrosis in the cortex and medulla; mild/moderate parenchymal collapse.

5

Glomeruli: majority of glomeruli sclerotic.

Tubules: >75 % of cortical tubules collapsed or degenerated; numerous dilated tubules.

Interstitium: severe parenchymal collapse, affecting cortex and medulla.