Diagnosis of inflammatory bowel disease: Potential role of molecular biometrics

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