Inflammatory bowel disease in paediatrics: Navigating the old challenges and emerging frontiers

Table 2 Key differentiating factors between Crohn’s disease and ulcerative colitis

Feature	CD	UC	IBD-U
Location	Any part of the GI tract (mouth to anus)	Limited to the colon and rectum	Colon only
Inflammation pattern	Discontinuous (skip lesions)	Continuous	Colonic, but with features unclear for CD/UC
Depth of involvement	Transmural (full thickness)	Mucosal and submucosal (superficial)	Overlapping or ambiguous features
Rectal involvement	Often spared (rectal sparing)	Always involved (proctitis)	Variable, can be involved
Microscopic features	Non-caseating granulomas (characteristic)	Crypt abscesses (common), no granulomas	Ambiguous; may have some transmural features but no granulomas
Fistulas/strictures	Common	Rare (unless long-standing, severe disease)	Rare, but can develop features over time
Perianal disease	Common	Rare	Rare
Cobble stoning	Characteristic endoscopic appearance (CD)	Absent	Absent (classic UC)
Surgical cure	Not curative (disease can recur)	Curative for GI manifestations	Variable, depends on evolving phenotype

CD: Crohn’s disease; UC: Ulcerative colitis; IBD-U: Inflammatory bowel disease-unclassified; GI: Gastrointestinal.