Table 1.

Definition of intestinal injury grading

Grade	Histological findings
0—No significant abnormality	Congestion, oedema, very occasional intravillous neutrophils, occasional apoptosis, hyperplastic lymphoid follicles.
1—Mild	Superficial mucosal erosion, patchy mucosal haemorrhage, prominent germinal centres with apoptosis and intrafollicular haemorrhage, focal, acute inflammatory infiltrate within the lamina propria, cryptitis, and crypt abscesses.
2—Moderate	Mucosal ulceration, mucosal/submucosal haemorrhage, intact muscularis propria.
3—Severe (localised)	Mucosal ulceration, focal transmural haemorrhage involving muscularis propria and serosa.
4—Severe (generalised)	Mucosal ulceration and diffuse transmural haemorrhage involving muscularis propria and serosa.