Crohn's vs Ulcerative Colitis

The two inflammatory bowel diseases · Week 13
Both are long-term inflammatory bowel disease (IBD). But they act in different ways. Crohn's can strike anywhere from mouth to anus. It makes patchy "skip" lesions that burrow full-thickness, meaning through the whole wall. Ulcerative colitis stays in the colon only. It runs continuous from the rectum up, and it stays shallow. Click each one.

Where it hits the gut

Here is the whole GI tract, mouth to anus. The orange and blue patches show where each disease inflames. Watch the pattern.
Pick a disease to see its pattern.
Pick a diseaseCrohn's · Ulcerative Colitis

What's happening

Side by side

FeatureCrohn'sUlc. Colitis
LocationAnywhere: mouth→anusColon only
PatternPatchy "skip" lesionsContinuous, from rectum up
DepthFull thicknessMucosa + submucosa
ProblemsFistulae, abscess, perforation↑ colon cancer risk
DiarrheaWatery, plus poor nutrient uptake (malabsorption)Bloody, nutrient uptake is fine