Diagnosis of inflammatory bowel disease: Potential role of molecular biometrics

Table 1 Microscopic features used for the diagnosis of Crohn’s colitis

Colon
Architecture
Crypt architectural irregularity	Focal
	Diffuse
Reduces crypt numbers/mucosal atrophy
Irregular surface
Chronic inflammation
Distribution I	Focal increased in intensity
	Patchy increase
Distribution II	Diffuse increase
	Superficial
Granulomas	Transmucosal
Mucin granulomas	Basal plasma cells
Polymorph inflammation
Lamina propria	Focal
Crypt epithelial polymorphs	Diffuse
Polymorph exudates
Epithelial changes
Erosion/ulceration
Mucin	Depletion
	Preservation
Paneth cells distal to hepatic flexure
Epithelial-associated changes
Increased intraepithelial lymphocytes > 15
Terminal ileum/Ileocecal /Cecum
Architecture	Villus irregularity
	Crypt architecture
Epithelial changes	Irregularity
	Pseudopyloric gland
	Metaplasia

Reproduced by permission of the publisher from ref. [38].

Table 2 Classic microscopic features in untreated ulcerative colitis (comparable Crohn’s colitis, hard criteria)

Feature	Ulcerative colitis	Crohn’s colitis
Diffuse	Continuous disease	Segmental disease
Rectal	Involvement	Variable rectal involvement
Disease	Worse distally	Variable disease severity
Fissures	No	Fissures, sinus, fistula
Transmural aggregates	No	Transmural lymphoid aggregates
Ileal involvement	No, exception during backwash ileitis	Ileal involvement
		Upper gastrointestinal involvement
Granulomas	No	Granulomas