Diagnostic Categories for Renal Allograft Biopsies ('95)
Kidney Transplantation

Diagnostic Categories for Renal Allograft Biopsies ('95)*
1. Normal, see Definitions
2. Hyperacute Rejection
Rejection presumed to be due to preformed antibody, usually characterized by polymorph accumulation in glomerular and peritubular capillaries at one hour post-transplant with subsequent endothelial damage and capillary thrombosis
3. Borderline Changes
Grade Histopathological Findings
"very mild acute rejection" This category is used when no intimal arteritis is present, but there is a mild or moderate focal mononuclear cell infiltration with foci of mild tubulitis (1 to 4 mononuclear cells/tubular cross section)
4. Acute Rejection
Grade Histopathological Findings
Grade I (mild) 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)
Grade II (moderate) Cases with (A) significant interstitial infiltration and foci of severe tubulitis (> 10 mononuclear cells/tubular cross section) and/or (B) mild or moderate intimal arteritis and/or (C) two foci of tubular basement membrane destruction with infiltrates of i2/i3 intensity
Grade III (severe) Cases with severe intimal arteritis and/or "transmural" arteritis with fibrinoid change and necrosis of medial smooth muscle cells. Recent focal infarction and interstitial hemorrhage without other obvious cause are also regarded as evidence for Grade III rejection
5. Chronic Allograft Nephropathy§
Grade Histopathological Findings
Grade I (mild) Mild chronic ischaemic or transplant glomerulopathy
Mild interstitial fibrosis and tubular atrophy
Grade II (moderate) Moderate chronic ischaemic or transplant glomerulopathy
Moderate interstitial fibrosis and tubular atrophy
Grade III (severe) Severe chronic ischaemic or transplant glomerulopathy
Severe interstitial fibrosis and tubular atrophy and tubular loss
6. Other
Changes not considered to be due to rejection, see Differential Diagnosis
§ Glomerular and vascular lesions help define type of chronic nephropathy; new-onset arterial fibrous intimal thickening suggests the presence of chronic rejection
* The recommended format of report is a descriptive narrative signout followed by numerical codes (Banff '93-95, Banff '97) 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
  1. 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.
  2. 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.


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Last Modified: Thu Jun 18 10:14:08 EDT 2009