Ulcerative colitis

Epidemiology:

• Incidence is stable at 6-15 per 100,000
• Worldwide distribution, but is more common in the West
• Incidence is lower in the non-whites with a particular penchant for Jews

Aetiopathogenesis:

Unknown aetiology but is thought to involve both genetic and environmental factors

Familial: UC is more common amongst relatives than in the general population

Smoking: ‘Protective’ to some degree (higher incidence of UC in non-smokers)

Pathology:

• Always affects the rectum (proctitis)
• May extend to infect the sigmoid and descending colon (left-sided colitis)
• May involve the rectum and entire colon (total colitis)

Macroscopic changes:

• The mucosa looks reddened, inflamed and bleeds very easily

Microscopic changes:

• The mucosa shows a chronic inflammatory cell infiltrate in the lamina propria
• Crypt abscesses
• Goblet cell depletion

Clinical features:

• Peak age of onset is 20-40yrs
• Women > men
• Diarrhoea with blood and mucus
• Lower abdominal discomfort
• Malaise
• Lethargy
• Anorexia
• Aphthous ulceration of the mouth

The disease may be mild, moderate or severe.

When the disease is confined to the rectum:

• Blood mixed in with the stool
• Urgency
• Tenesmus

In an acute attack:

• Bloody diarrhoea (occasionally just blood and mucus are passed)
• 10-20 liquid stools per day
• Diarrhoea also occurs at night

Examination:

• The abdomen may be slightly distended

Ulcerative colitis

• PR exam will show the presence of blood
• Sigmoidoscopy is always abnormal and shows an inflamed, bleeding, friable mucosa (a biopsy should be taken to confirm the dx)

Extra GI manifestations:

Eyes:

• Uveitis
• Episcleritis
• Conjunctivitis

Joints:

• Monoarticular arthritis
• Ankylosing spondylitis
• Sacroiliitis

Skin:

• Erythema nodosum
• Pyoderma gangrenosum

Other:

• Fatty liver
• Sclerosing cholangitis

Investigations:

1. Blood tests:

• Normocytic normochromic anaemia of chronic disease
• Fe/folate deficiency occurs
• Raised ESR/CRP/WCC
• Hypoalbuminaemia in severe disease

2. Stool cultures

3. Plain AXR:

• Look for signs of colonic dilatation

4. Colonoscopy

Complications:

• Toxic dilatation
• Perforation
• Severe haemorrhage
• Ca colon
• Perianal abscess

Medical Mx:

• All pts are rx with a 5-ASA (5-Amino Salicylic Acid) compound. It is used to decrease the no. of relapses when taken long-term.

Mild attacks: Local rectal steroids in the form of enemas or foam.

Moderate attacks: Prednisolone (40mg/daily po). Pts with their first attack or those who do not respond quickly should be admitted to hospital.

Ulcerative colitis

Severe attacks: Prednisolone (60mg/6h IV) or Hydrocortisone (100mg/6h IV). IV correction of fluid/electrolytes. A/Bs for concomitant sepsis.

Surgical Mx:

• In UC, the disease is confined to the colon and, therefore, a colectomy is curative.
• The usual indication for surgery is usually a severe attack which fails to respond to medical rx
• A prophylactic colectomy is sometimes performed in those who have a high cancer risk

Protocolectomy with an ileostomy:

• This is the standard operation in which the colon and rectum are removed and the ileum is brought out through an opening in the RIF

Problems associated with ileostomies include:

• Mechanical problems
• Dehydration (particularly in hot climates)
• Psychosexual problems
• Infertility in men

Colectomy with an ileorectal or ileoanal anastomosis:

• These procedures avoid the need for an ileostomy.
• Ileorectal anastomoses leave a diseased rectum in situ and frequent diarrhoea still occurs.