Ulcerative colitis


  • Neutrophil and lymphoplasmacytic inflammation through intestinal wall (mucosa and submucosa) with crypt abscesses
  • Onset typically in late teens or 50-60yo
  • M = F
  • Smoking protective
  • Usually insidious : recurrent diarrhoea, bloody stools, tenesmus, crampy abdo pain, low pyrexia, wt loss
  • Occasionally acute arthropathy, scleritis, erythema nodosum, and pyoderma gangrenosum
  • Rarely fulminant bleeding or massive colonic distension ± perforation

DDx rectal bleeding

  • Infectious colitis
  • Ischaemic colitis
  • NSAID enteropathy
  • Diverticulitis
  • C. difficile


  • FBC (anaemia, leukocytosis)
  • LFT (low albumin if protein losing enteropathy)
  • U&E (diarrhoea losses)
  • Baseline ESR and CRP
  • PFA (one of few indications) to exclude megacolon
  • CT if unsure of other pathology
    • Thick colonic wall, pericolic fat stranding
  • Definite Dx = sigmoidoscopy and Bx
    • CONTRA-indicated in megacolon


  • ABC re significant blood loss, perforation, sepsis etc
  • Rehydration
  • ± blood transfusion
  • Exclude / beware megacolon (involve surgeons EARLY)
  • Bowel rest
  • Steroids for acute flare
  • 5-aminosalicylic acid (ASA) to maintain remission
  • LMWH if not active bleeding (high risk VTE)
  • Immunomodulators (e.g. Infliximab) in refractory disease
  • Consider colectomy in severe cases

Content by Dr Íomhar O' Sullivan. Last reviewed by Dr ÍOS 12/04/23.