Ulcerative colitis


  • Inflammation tends to be progressively more severe from proximal to distal colon
  • Rectum is almost always involved
  • Peak incidence occurs in second and third decades of life

Crohn's disease vs. ulcerative colitis

Finding Crohn's disease Ulcerative colitis
Depth of inflammation May be transmural, deep into tissues Shallow, mucosal
Distribution of disease Patchy areas of inflammation (skip lesions) Continuous area of inflammation
Terminal ileum involvement Commonly Seldom
Colon involvement Usually Always
Rectum involvement Seldom Usually (95%)
Involvement around anus Common Seldom
Stenosis Common Seldom

Clinical Features


  • Mild
    • <4 bowel movements per day
    • No systemic symptoms
    • Few extraintestinal manifestations
    • Occasional constipation and rectal bleeding
  • Moderate
  • Severe

Differential Diagnosis




  • CBC
  • Chemistry
  • LFTs/lipase
  • Consider:
    • ESR/CRP
    • Fecal calprotectin[1] (typically requested by GI)
    • Type and screen (if significant bleeding)
  • Imaging
    • Consider CT based on clinical features and need to rule out more concerning processes


  • Positive atypical p-ANCA and negative ASCA is specific for ulcerative colitis


  1. Rule-out complications:
  2. Steroids
    • Parenteral vs PO depending on severity
      • PO: prednisone 40mg x 2wks, then decrease by 5mg per week


  • Admit for severe complication or severe flare requiring IV steroids

See Also


  1. van Rheenen PF, Van de Vijver E, Fidler V. Faecal calprotectin for screening of patients with suspected inflammatory bowel disease: diagnostic meta-analysis. BMJ. 2010;15(341):c3369.