Histological grades of acute graft versus host disease
| Grade | Histological features |
|---|---|
| Grade I | Focal or diffuse vacuolar change of the basal keratinocytes |
| Grade II | Necrotic keratinocytes in the epidermis |
| Grade III | Widespread keratinocyte necrosis; separation of the dermo–epidermal junction |
| Grade IV | Complete necrosis of the epidermis |