Ulcerative colitis

Definition

• • Intermittent form of inflammatory bowel disease affecting the colon, that includes characteristic ulcers in the colon

Risk Factors

• • Genetics

  • Diet

  • Recent smoking cessation

    • hydrogen cyanide from cigarette smoke reacting with hydrogen sulfide to produce the nontoxic isothiocyanate?

Differential diagnosis

Epidemiology

• • 35–100 / 100,000 in the United States

  • peak incidence 15 to 25

  • bimodal distribution in age of onset, with a second peak in incidence occurring in the 6th decade of life

  • Higher incidences are seen in northern locations

Aetiology

• • Autoimmune??

Clinical features

• • Often mucus-like faeces/diarrhoea with blood

• Tenesmus

  • Shallow, mucosal inflammation, limited to colon + rectum

  • Continuous area of inflammation

  • Non-peri-intestinal crypt granulomas not seen

• Extra-intestinal features:

  • • aphthous ulcers of the mouth

    • Iritis or uveitis

  • Episcleritis

  • Seronegative arthritis

  • Ankylosing spondylitis

  • Sacroiliitis

  • Erythema nodosum

  • Pyoderma gangrenosum

    • Deep venous thrombosis and pulmonary embolism

  • Autoimmune hemolytic anemia

  • clubbing

  • Primary sclerosing cholangitis

Pathophysiology

• • Unknown

  • An increased amount of colonic sulfate-reducing bacteria has been observed in some patients with ulcerative colitis

Investigations

• • A complete blood count

    • anemia; thrombocytosis occasionally seen

  • Electrolyte studies and renal function tests are done

    • chronic diarrhea may be associated with hypokalemia, hypomagnesemia and pre-renal failure.

  • Liver function tests

    • screen for bile duct involvement: primary sclerosing cholangitis.

• X-ray

• Urinalysis

  • Stool culture

    • rule out parasites and infectious causes.

  • Erythrocyte sedimentation rate

    • elevated sedimentation rate indicates that an inflammatory process is present.

• C-reactive protein

  • Endoscopy

Management

a) conservative

b) medical

• • Aminosalicylates

  • Corticosteroids

  • Immunosuppressive drugs

  • Biological treatment

c) surgical

• • Colectomy

    • necessary in the event of: exsanguinating hemorrhage, frank perforation or documented or strongly suspected carcinoma

Prognosis