Diagnostic Categories for Renal Allograft Biopsies ('97)

Diagnostic Categories for Renal Allograft Biopsies ('97)*
1. Normal, see Definitions

2. Antibody mediated rejection-demonstrated to be due, at least in part, to anti-donor antibodies

Type Histopathological Findings

Immediate (Hyperacute) Polymorph accumulation in glomerular and peritubular capillaries with subsequent endothelial damage and capillary thrombosis

Delayed (Accelerated Acute)

3. Borderline Changes:"Suspicious" for acute rejection

Grade Histopathological Findings

"Suspicious" This category is used when no intimal arteritis is present, but there are foci of mild tubulitis (1 to 4 mononuclear cells/tubular cross section) and at least i1

4. Acute Rejection

Type (Grade) Histopathological Findings

IA Cases with significant interstitial infiltration (>25% of parenchyma affected) and foci of moderate tubulitis (> 4 mononuclear cells/tubular cross section or group of 10 tubular cells)

IB Cases with significant interstitial infiltration (> 25% of parenchyma affected) and foci of severe tubulitis (> 10 mononuclear cells/tubular cross section or group of 10 tubular cells)

IIA Cases with significant interstitial infiltration and mild to moderate intimal arteritis (v1)

IIB Cases with severe intimal arteritis comprising > 25% of the lumenal area (v2)

III Cases with "transmural" arteritis or fibrinoid change and necrosis of medial smooth muscle cells (v3 with lymphocytic inflammation)

5. Chronic/Sclerosing Allograft Nephropathy§

Grade Histopathological Findings

Grade I (mild) Mild interstitial fibrosis and tubular atrophy without (a) or with (b) specific vascular changes suggesting chronic rejection

Grade II (moderate) Moderate interstitial fibrosis and tubular atrophy without (a) or with (b) specific vascular changes suggesting chronic rejection

Grade III (severe) Severe interstitial fibrosis and tubular atrophy without (a) or with (b) specific vascular changes suggesting chronic rejection

6. Other

Changes not considered to be due to rejection, see Differential Diagnosis

§ Glomerular and vascular lesions help define type of chronic nephropathy; chronic/recurrent rejection can be diagnosed if typical vascular lesions are seen

* The recommended format of report is a descriptive narrative signout followed by numerical codes in parentheses. Categorization should in the first instance be based solely on pathologic changes, then integrated with clinical data as a second step. More than one diagnostic category may be used if appropriate

References

Solez K, et al. International standardization of criteria for the histologic diagnosis of renal allograft rejection: The Banff working classification of kidney transplant pathology. 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.
Racusen L, et al. The Banff 97 working classification of renal allograft pathology. Kidney Int 1999;55:713-723

Diagnostic Categories for Renal Allograft Biopsies ('97)*
1. Normal, see Definitions
2. Antibody mediated rejection-demonstrated to be due, at least in part, to anti-donor antibodies
Type	Histopathological Findings
Immediate (Hyperacute)	Polymorph accumulation in glomerular and peritubular capillaries with subsequent endothelial damage and capillary thrombosis
Delayed (Accelerated Acute)
3. Borderline Changes:"Suspicious" for acute rejection
Grade	Histopathological Findings
"Suspicious"	This category is used when no intimal arteritis is present, but there are foci of mild tubulitis (1 to 4 mononuclear cells/tubular cross section) and at least i1
4. Acute Rejection
Type (Grade)	Histopathological Findings
IA	Cases with significant interstitial infiltration (>25% of parenchyma affected) and foci of moderate tubulitis (> 4 mononuclear cells/tubular cross section or group of 10 tubular cells)
IB	Cases with significant interstitial infiltration (> 25% of parenchyma affected) and foci of severe tubulitis (> 10 mononuclear cells/tubular cross section or group of 10 tubular cells)
IIA	Cases with significant interstitial infiltration and mild to moderate intimal arteritis (v1)
IIB	Cases with severe intimal arteritis comprising > 25% of the lumenal area (v2)
III	Cases with "transmural" arteritis or fibrinoid change and necrosis of medial smooth muscle cells (v3 with lymphocytic inflammation)
5. Chronic/Sclerosing Allograft Nephropathy§
Grade	Histopathological Findings
Grade I (mild)	Mild interstitial fibrosis and tubular atrophy without (a) or with (b) specific vascular changes suggesting chronic rejection
Grade II (moderate)	Moderate interstitial fibrosis and tubular atrophy without (a) or with (b) specific vascular changes suggesting chronic rejection
Grade III (severe)	Severe interstitial fibrosis and tubular atrophy without (a) or with (b) specific vascular changes suggesting chronic rejection
6. Other
Changes not considered to be due to rejection, see Differential Diagnosis
§ Glomerular and vascular lesions help define type of chronic nephropathy; chronic/recurrent rejection can be diagnosed if typical vascular lesions are seen
* The recommended format of report is a descriptive narrative signout followed by numerical codes in parentheses. Categorization should in the first instance be based solely on pathologic changes, then integrated with clinical data as a second step. More than one diagnostic category may be used if appropriate
References Solez K, et al. International standardization of criteria for the histologic diagnosis of renal allograft rejection: The Banff working classification of kidney transplant pathology. 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. Racusen L, et al. The Banff 97 working classification of renal allograft pathology. Kidney Int 1999;55:713-723

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