Quantitative Criteria for Tubulitis ("t") Score (assumes minimum sampling)
t0	No mononuclear cells in tubules
t1	Foci with 1 to 4 cells/tubular cross section or 10 tubular cells
t2	Foci with 5 to 10 cells/tubular cross section
t3	Foci with >10 cells/tubular cross section, or the presence of at least two areas of tubular basement membrane destruction accompanied by i2/i3 inflammation and t2 tubulitis elsewhere in the biopsy.

Quantitative Criteria for Mononuclear Cell Interstitial Inflammation ("i")
i0	No or trivial interstitial inflammation
i1	Up to 25% of parenchyma inflamed cells
i2	26 to 50% of parenchyma inflamed
i3	>50% of parenchyma inflamed

Quantitative Criteria for the Early Type of Allograft Glomerulitis ("g")
g0	No glomerulitis
g1	Glomerulitis in a minority of glomeruli
g2	Segmental or global glomerulitis in about 25 to 75% of glomeruli
g3	Glomerulitis (mostly global) in all or almost all glomeruli

Quantitative Criteria for Arteriolar Hyaline Thickening ("ah")
ah0	No PAS-positive hyaline thickening
ah1	Mild-to-moderate PAS-positive hyaline thickening in at least one arteriole
ah2	Moderate-to-severe PAS-positive hyaline thickening in more than one arteriole
ah3	Severe PAS-positive hyaline thickening in many arterioles

Quantitative Criteria for Intimal Arteritis ("v")
v0	No arteritis
v1	Mild-to-moderate intimal arteritis in at least one arterial cross section
v2	Moderate-to-severe intimal arteritis in more than one arterial cross section
v3	Severe intimal arteritis in many arterial cross sections and/or "transmural" arteritis, fibrinoid change and medial smooth muscle necrosis, often with patchy infarction and interstitial hemorrhage

Quantitative Criteria for Allograft Glomerulopathy ("cg")
cg0	No glomerulopathy
cg1	Mesangial matrix expansion and BM thickening, ± double contours, in capillary loops affecting up to 25% of nonsclerotic glomeruli
cg2	Increasd severity of changes described above affecting 26 to 50% of nonsclerotic glomeruli
cg3	Severe changes of classic transplant glomerulopathy affecting more than 50% of nonsclerotic glomeruli and with double contours in many capillary loops

Quantitative Criteria for Interstitial Fibrosis ("ci")
ci0	Interstitial fibrosis tissue in up to 5% of cortical area
ci1	Mild Interstitial fibrosis tissue in 6 to 25% of cortical area
ci2	Moderate interstitial fibrosis of 26 to 50% of cortical area
ci3	Moderate interstitial fibrosis of >50% of cortical area

Quantitative Criteria for Tubular Atrophy ("ct")
ct0	No tubular atrophy
ct1	Tubular atrophy in up to 25% of the area of cortical tubules
ct2	Tubular atrophy involving 26 to 50% of the area of cortical tubules
ct3	Tubular atrophy of >50% of the area of cortical tubules

Quantitative Criteria for Fibrous Intimal Thickening ("cv")
cv0	No chronic vascular changes
cv1	Vascular narrowing of up to 25% lumenal area by fibrointimal thickening of arteries ± breach of internal elastic lamina or presence of foam cells or occasional mononuclear cells
cv2	Increased severity of changes described above with 26 to 50% narrowing of vascular lumenal area
cv3	Severe vascular changes with >50% narrowing of vascular lumenal area

References Solez K, et al. International standardization of criteria for the histologic diagnosis of renal allograft rejection: The Banff working classification of kidney transplantation. Kidney Int 1993;44(2):411-22. Solez K, et al. Report of the third Banff conference on allograft pathology (July 20-24, 1995) on classification and lesion scoring in renal allograft pathology. Trans Proc 1996;28(1):441-4.