Table 3.

The histologic activity index (HAI) scoring system for inflammation-associated histological changes in the colon.

Score	Infiltrate	Extent of inflammatory infiltrate	Goblet cell mucin depletion	Nature of mucosal changes
0	Normal/physiologic	None	None	None
1	Minimal elevation	Single or rare, scattered foci	Minimal	Minimal deterioration
2	Expanded within or beyond lamina propria	Patchy, moderately abundant	Moderate	More deterioration
3	Crypt abscesses or submucosal involvement	Extensive	Extensive	More thanatosis
4	Diffuse	Inflammatory cells in the gut lumen	N/A	N/A