Diverticular Disease

Question 1

What is a diverticulum and where do they commonly occur?

Answer 1

1. Outpouching of the gut wall.

2. Sites entry of perforating arteries within the sigmoid colon.

Question 2

What is the difference between diverticulosis, diverticular disease, and diverticulitis?

Answer 2

1. Diverticulosis - diverticula are present (asymptomatic)
2. Diverticular disease - diverticula are symptomatic.
3. Diverticulitis - inflammation of a diverticulum.

Question 3

What is the pathology of diverticular disease?

Answer 3

1. Pouch of colonic mucosa herniated through muscularis propria, lying in subserosal fat.
2. Prone to perforation when they are obstructed or inflamed.
3. Within sigmoid colon as it has the narrowest lumen and suffers the highest pressure.

Question 4

What percentage of Caucasians have diverticulosis by the age of 60?

Answer 4

50%, majority are asymptomatic.

Question 5

What are the two main factors causing diverticula formation?

Answer 5

1. High intraluminal pressures

2. Areas of weakness in the colonic wall

Question 6

What causes the high intraluminal pressures causing diverticulosis?

Answer 6

Lack of dietary fibre = hard stools, this requires increased muscular effort = muscle hypertrophy and increased intraluminal pressure.

Question 7

Causes areas of weakness in the colonic wall closing diverticulosis?

Answer 7

Decreased muscle strength forces mucosa to herniate through muscle layers.

Question 8

Why is the sigmoid colon a common site for diverticula?

Answer 8

It has the smallest diameter of any portion of the large bowel and therefore is the site where intraluminal pressure is potentially the highest.

Question 9

How is diverticular disease diagnosed?

Answer 9

1. Incidental finding on colonoscopy

2. CT abdomen where is best to confirm acute diverticulitis - can identify extent of disease and complications.

Question 10

What are the risk factors for diverticular disease?

Answer 10

Low dietary fibre and >50-years old

Question 11

What is this a presentation of?

Altered bowel habit (constipation/diarrhoea), left sided colicky pain relieved by defecation, nausea, flatulence.

Answer 11

Diverticular disease

Question 12

What is the treatment for asymptomatic and symptomatic diverticular disease?

Answer 12

1. Asymptomatic - no treatment

2. Symptomatic - increase dietary fibre

Question 13

What causes acute diverticulitis?

Answer 13

Faeces lodges.in diverticula or erosion of diverticular wall from high intraluminal pressure.

Question 14

What is this a presentation of?
Fever, raised WCC/CRP/ESR, tender left lower quadrant and guarding, localised or generalized parasitism, rectal bleeding (abrupt, and profuse).

Answer 14

Acute diverticulitis

Question 15

How do you treat acute diverticulitis?

Answer 15

1. Mild attacks - bowel rest (just fluids) and antibiotics.
2. More severe - analgesia, antibiotics (co-amoxiclav or ciprofloxacin and metronidazole), IV antibiotics if no improvement with oral in 4 days.

Question 16

What are the complications diverticular disease?

Answer 16

1. Haemorrhage - sudden and painless
2. Perforation - ileus, peritonitis, shock
3. Fistulae - between sigmoid colon and bladder, frothy urine, UTIs
4. Abscesses - may path rate into abdominal cavity (peritonitis)
5. Post-infective strictures - fibrosis from repeated inflammation and healing smooth muscle hypertrophy and hyperplasia (rule out colon carcinoma with biopsy)