Table 1.

Colon and Ileum Histologic Examination Scoring

Region	Layer	Criteria	Score
Colon	Longitudinal muscle	Layered muscle cells with few collagen strands between, <10% collagen	0
Loss of muscle cells, with prominent collagen between, 10%–50% collagen	1
Substantial loss of muscle cells, some areas may have no muscle cells. Prominent collagen in muscle layer, >50% collagen	2
Circular muscle	Muscle cells plump, eight or more layers, <10% collagen	0
Muscle cells smaller and fewer, only four to seven layers, 10%–50% collagen	1
Muscle cells smaller and substantially fewer, less than four layers, >50% collagen	2
Submucosa	Thin with fibroblasts, no or extremely rare macrophages	0
Thickened with some macrophages	1
Thickened more than twofold normal with numerous macrophages	2
Mucosa	Goblet cells small at bases of glands and in gland walls, rare at surface	0
Goblet cells swollen and commonly observed at surface as well as at bases and in walls of glands	1
Ileum	Longitudinal muscle	Layered muscle cells with few collagen strands between, <10% collagen	0
Loss of muscle cells, with prominent collagen between, 10%–50% collagen	1
Substantial loss of muscle cells, some areas may have no muscle cells. Prominent collagen in muscle layer, >50% collagen	2
Circular muscle	Muscle cells plump, five or more layers, <10% collagen	0
Muscle cells smaller and fewer, only two to four layers, 10% to 50% collagen	1
Muscle cells smaller and substantially fewer, less than layers, >50% collagen	2
Submucosa	Thin with fibroblasts, no or extremely rare macrophages	0
Thickened with some macrophages	1
Thickened more than twofold normal with numerous macrophages	2
Mucosa	Mucosa intact	0
Disruptions to the mucosa	1

Scoring system designed to be objective, 8-point scale for each region [0 (normal); 7 (severely affected)].