Inflammatory bowel diseases: ulcerative colitis and Crohn’s disease, and other types of colitis

1. Big picture

Inflammatory bowel disease (IBD) mainly means ulcerative colitis (UC) and Crohn’s disease (CD). For a surgery state exam, the key question is not only “What is IBD?” but:

When does a medical disease become a surgical disease?

The surgical logic is:

Chronic diarrhoea ± blood/mucus + abdominal pain → suspect IBD → confirm with endoscopy/biopsy + exclude infection → treat medically first → operate for complications, cancer risk, emergency deterioration, or failed medical therapy.

The most important distinction:

| Feature | Ulcerative colitis | Crohn’s disease | | ----------------