2007 Banff Schema for Grading of Acute Pancreas Allograft Rejection
|
| |
|
Category |
Histopathology |
Comments |
Normal |
No inflammation OR inactive septal mononuclear inflammation not involving veins, arteries, ducts, or acini |
1. Fibrous tissue limited to septa in appropriate amounts; no injury or atrophy of acinar regions |
Indeterminate for Acute Rejection |
"Active" septal inflammation without other criteria for rejection (see below) |
1. Any venulitis or ductitis qualifies for at least mild acute rejection (or more depending on other features)
2. Active inflammation refers to blastic lymphoctyes with variable numbers of eosinophils |
Grade I (Mild acute cell-mediated rejection) |
"Active" septal inflammation with involvement of septal veins (venulitis) and/or ducts (ductitis)
AND/OR focal (1-2 foci/lobule) acinar "active" inflammation with minimal/no acinar cell injury |
1. Any venulitis or ductitis is sufficient for diagnosis; nerve branches usually involved but rarely sampled; focal acinar "active" inflammation alone also adequate for diagnosis |
| Grade II (Moderate acute cell-mediated rejection) |
Minimal intimal arteritis
AND/OR multiple (3 or more foci/lobule) foci of acinar "active" inflammation with single cell injury/dropout
|
1. Minimal intimal arteritis refers to occasional subendothelial lymphocytes without obvious endothelial swelling/activation or injury |
| Grade III (Severe acute cell-mediated rejection) |
Widespread acinar inflammation with confluent areas of acinar cell injury/necrosis
AND/OR moderate to severe intimal arteritis
AND/OR necrotizing arteritis |
1. Any of these three findings is sufficient for the diagnosis
2. Acinar inflammation may contain variable lymphocytes, eosinophils, and neutrophils as well as edema and/or hemorrhage
3. Moderate/severe intimal arteritis consists of more frequent subendothelial lymphocytes with evidence of intimal injury, such as cell swelling, fibrin leakage, etc.
4. Necrotizing arteritis may also occur in antibody-mediated rejection and C4d stain should be performed. |
Chronic Active Cell-Mediated Rejection (return to top) |
Category |
Histopathology |
Comments |
| Chronic active cell-mediated rejection |
Arterial luminal narrowing due to intimal proliferation of fibroblasts, myofibroblasts, smooth muscle cells, with admixed T lymphocytes and macrophages ("active" transplant arteriopathy) |
1. May represent transition between intimal arteritis and chronic transplant arteriopathy related to suboptimal immunosuppression
2. Rarely seen in needle biopsies, more often seen in allograft resection related to chronic rejection |
|
Category |
Histopathology |
Comments |
| Hyperacute antibody-mediated rejection |
Widespread deposition of immunoglobulin (usu. IgG) and complement (e.g., C4d) with resultant arteritis and venous thrombosis, hemorrhagic necrosis and allograft failure usually within 1 hour after revascularization |
1. In all cases, diagnosis is dependent upon demonstration of a) graft dysfunction, b) capillary complement deposition (i.e., C4d positivity), AND c) donor specific antibodies in serum.
2. If C4d and only 1 of the other 2 features is found, then the diagnosis"suspicious for" antibody-mediated rejection is more appropriate
3. In cases in which vascular thrombosis is the predominant finding, the differential diagnosis lies between antibody-mediated rejection and "technical failure". |
| Accelerated antibody-mediated rejection |
Similar to hyperacute, but changes evolve over hours to days after revascularization. |
| Acute antibody-mediated rejection |
Allograft dysfunction in first posttransplant weeks; histology varies from normal to margination of neutrophils and mononuclear cells to thrombosis and necrosis; |
Chronic Active Antibody-Mediated Rejection (return to top) |
Category |
Histopathology |
Comments |
| Chronic active antibody-mediated rejection |
Features of chronic rejection/graft sclerosis together with C4d positivity in capillaries |
1. May also have vascular fibrinoid necrosis/thrombosis indicating ongoing antibody-mediated rejection
2. C4d positivity, graft dysfunction, and donor-specific antibodies are all required for a diagnosis as in other forms of antibody-mediated rejection |
Chronic Rejection (Graft Sclerosis) (return to top) |
Category |
Histopathology |
Comments |
| Chronic allograft rejection Stage I (mild graft sclerosis) |
Fibrous septa expanded but comprise less than 30% of biopsy surface area. Acinar lobules have irregular contours due to erosion |
|
| Chronic allograft rejection Stage II (moderate graft sclerosis) |
Fibrous septa expanded to 30-60% of biopsy surface area. Most lobules have irregular contours and central areas are affected, with fibrous strands extending between lobules |
|
| Chronic allograft rejection Stage III (severe graft sclerosis) |
Fibrous septa comprise over 60% of biopsy surface area with only a few areas of residual acini and/or islets |
|
| Reference: Drachenberg CB et al. Banff schema for grading pancreas allograft rejection: Working proposal by a multi-disciplinary international consensus panel. Am J Transplant 8:1-13, 2008. |
