Table 1.

Histological score system of colitis

Score	inflammation severity	inflammation extent	crypt damage	percent area involvement
0	normal colonic mucosa;	normal colonic mucosa and submucosa;	normal colonic mucosa;	0%
1	mild inflammation: either focal or wildly separated multifocal inflammation;	inflammation extent to mucos;	shortening and loss of the basal one-third of the actual crypts with mild inflammation and edema;	1–25%
2	moderate inflammation: either multifocal or locally extensive inflammation;	inflammation extent to mucosa and submucosa;	loss of the basal two-thirds of the crypts with moderate inflammation;	26–50%
3	severe inflammation: mucosal ulcers with monocytes and polymorphonuclear leukocytes;		loss of the entire crypts with severe inflammation in the mucosa, but with retention of the surface epithelium;	51–75%
4			loss of the entire crypt and surface epithelium;	76–100%