Ulcerative Colitis

• Ulcerative colitis (UC)


  The most common form of inflammatory bowel disease, alongside Crohn's disease (CD)
• There are approximately 5 million cases of ulcerative colitis around the world and incidence is increasing
• The peak age of onset is between those aged 15-40yrs old, however incident cases in people >60yrs are increasing (accounting up to 20% of new diagnoses)
• Males and females are affected equally
• Ulcerative colitis


  Typically follows a remitting and relapsing course
• A severe fulminant exacerbation may be life-threatening, resulting in severe systemic upset, toxic megacolon, colonic perforation, and even mortality
• Pathogenesis of ulcerative colitis

  • Complex and aetiology remains incompletely understood
  • Occurs after environmental exposures in individuals with a genetic predisposition
  • Epithelial barrier defects, dysregulated immune responses, and dysbiosis being key in initiating and perpetuating inflammation
• Ulcerative colitis


  Characterised by diffuse continual mucosal inflammation of the large bowel, beginning in the rectum and spreading proximally
• Up to 20% cases also having terminal ileal involvement, termed "backwash ileitis"
• Histological changes in ulcerative colitis


  • Non-granulomatous inflammation of the mucosa and submucosa
  • Crypt abscesses
  • Goblet cell hypoplasia
• Pseudopolyps


  Raised areas of inflamed tissue
• Smoking appears to have a protective role in Crohn's disease
• Differences between ulcerative colitis and Crohn's disease

  • Site involvement: large bowel vs entire GI tract
  • Inflammation: mucosal involvement only vs transmural involvement
  • Microscopic changes: crypt abcess formation, reduced goblet sells, non-granulomatous vs granulomatous (non-caseating)
  • Macroscopic changes: continuous inflammation (proximal from rectum), pseudopolyps and ulceration vs discontinuous inflammation (skip lesions), fissure and deep ulcers (cobblestone appearance), fistula formation
• Proctitis


  Inflammation confined to the rectum only
• Bloody diarrhoea, with visible blood in stool reported in more than 90% of cases
• Other symptoms of ulcerative colitis


  • Mucus discharge per rectum
  • Increased stool frequency and urgency
  • Tenesmus
• Patients presenting with more widespread colonic involvement may develop clinical features of dehydration or systemic symptoms such as malaise, anorexia, or low-grade pyrexia
• In patients with an acute severe flare of ulcerative colitis, or particularly with toxic megacolon or colonic perforation, patients will complain of severe abdominal pain
• Truelove and Witt criteria for grading severity of ulcerative colitis exacerbation

  • Mild: <4 bowel movements per day, minimal blood in stool, no pyrexia, pulse <90bpm, no anaemia, ESR ≤30mm/hr
  • Moderate: 4-6 bowel movements per day, mild to severe blood in stool, no pyrexia, pulse <90bpm, no anaemia, ESR 30mm/hr
  • Severe: >6 bowel movements per day, visible blood in stool, pyrexia, pulse >90bpm, anaemia, ESR >30mm/hr
• Extra-intestinal manifestations of ulcerative colitis

  • Musculoskeletal (e.g. enteropathic arthritis, osteoporosis, nail clubbing)
  • Skin (e.g. Erythema Nodosum, pyoderma gangrenosum)
  • Eyes (e.g. episcleritis, anterior uveitis, iritis)
  • Hepatobiliary (e.g. primary sclerosing cholangitis)
• Around 70% of patients with primary sclerosing cholangitis will have IBD, whilst around 5% of patients with IBD will have primary sclerosing cholangitis
• Differential diagnoses for ulcerative colitis


  • Crohn's disease
  • Chronic infections (schistosomiasis, giardiasis, or abdominal tuberculosis)
  • Mesenteric ischaemia
  • Radiation colitis
  • Malignancy
  • Irritable bowel syndrome
  • Coeliac disease
• Faecal calprotectin test


  Good sensitivity for inflammatory bowel disease
• Colonoscopy with biopsies


  Most sensitive and specific tool to establish a diagnosis of ulcerative colitis
• Endoscopic findings in ulcerative colitis


  • Mild: erythema and vascular congestion
  • Moderate to severe: complete loss of vascular patterns and mucosal friability, with ulcer and pseudopolyp formation
• Montreal score


  Used for quantifying disease extent
• Mayo score


  Used for quantifying disease severity
• Plain film abdominal radiographs (AXR) in an acute flare of ulcerative colitis may show mural thickening, thumb-printing, or, in chronic cases, a lead-pipe colon
• Urgent CT imaging may be required in the acute setting to assess for any evidence of bowel obstruction (from stricturing disease), toxic megacolon, or bowel perforation
• All patients with UC should be referred to IBD nurse specialists and patient support groups
• Enteral nutritional support should be considered, especially in young patients with growth concerns, and low residue diets can often be beneficial
• Due to increased risk of colorectal malignancy, endoscopic surveillance is offered to people who have had the disease for >10 years with >1 segment of bowel affected
• Medical management of mild to moderate ulcerative colitis

  1. Induction and maintenance of remission with mesalazine

  2. Corticosteroids if no response to mesalazine
• Medical management of moderate to severe ulcerative colitis


  1. Commence corticosteroids

  2. Use biologic agents (e.g. anti-TNF, vedolizumab) or thiopurines (e.g. azathioprine) to maintain remission
• Medical management of acute severe ulcerative colitis


  1. Intravenous corticosteroid therapy

  2. Ciclosporin or infliximab therapy if no response

  3. Fluid resuscitation and prophylactic heparin with anti-embolic stockings
• Surgical management is recommended if there is no improvement after 4–7 days of maximal medical treatment
• Indications for surgery in ulcerative colitis


  • Emergency: toxic megacolon, colonic perforation, uncontrolled bleeding
  • Elective: medically refractory disease, medication intolerance, colorectal cancer or endoscopically irresectable dysplasia
• Proctocolectomy and ileal-pouch anal anastomosis (IPAA)

  Staged surgical approach: 1) subtotal colectomy with end ileostomy, 2) completion proctectomy and IPAA formation with temporary loop ileostomy, 3) ileostomy reversal
• Proctocolectomy with end ileostomy

  Reasonable surgical option, with similar quality of life outcomes, requiring less operations and not associated with any complications from an IPAA
• Complications of ulcerative colitis


  • Toxic megacolon
  • Colorectal adenocarcinoma
  • Pouchitis (in those who have undergone an IPAA)