Histopathological assessment of the microscopic activity in inflammatory bowel diseases: What are we looking for?

Table 5 Global Histology Activity Score

Histopathological variable	Grade
Epithelial damage	0 = Normal; 1 = Focal; 2 = Extensive
Architectural changes	0 = Normal; 1 = Moderate; 2 = Severe
Mononuclear cells in lamina propria	0 = Normal; 1 = Moderate increase; 2 = Severe increase
Neutrophils in lamina propria	0 = Normal; 1 = Moderate increase; 2 = Severe increase
Neutrophils in epithelium	1 = Surface epithelium; 2 = Cryptitis; 3 = Crypt abscess
Erosion or ulceration	0 = No; 1 = Yes
Granuloma	0 = No; 1 = Yes
Number of segmental biopsy specimens affected	1 = < 1/3; 2 = 1/3-2/3; 3 = > 2/3

Each variable is scored independently. The total score is the sum of all individual scores.