Diverticulitis

Question 1

Diverticula

Answer 1

• Outpouching of mucous membrane through muscle wall of bowel
• false diverticula: lack of normal muscle coats
• sigmoid and descending colon
• 60% of 70 years old

Question 2

Pathogenesis

Answer 2

• diverticulosis: hypertrophy of muscle of sigmoid colon

- sites of potential weakness in bowel wall corresponding to points of entry of supplying vessels to bowel

Question 3

Risk factor

Answer 3

• low fibre diet
• structural abnormalities: Marfan’s and Ehlers-Danlos syndrome, polycystic kidney disease
• abnormal motility and increased luminal pressure: chronic and excessive segmental contractions produce high intra luminal pressure, enteric neuropathy–> reduced number of pacemaker cells in myenteric plexus

Question 4

Complication of diverticula

Answer 4

1. diverticulitis –> perforation
   - General peritoneal cavity –> peritonitis
   - pericolic tissue –> pericolic abscess
   - adjacent structure (bladder, small bowel, bladder) –> fistula
2. Large bowel obstruction
   - due to muscular hypertrophy and inflammatory fibrosis
3. Haemorrhage
   - erosion of vessel within fundus of diverticulum

Question 5

Acute diverticulitis

Answer 5

• acute onset of low central abdominal pain which shift to LIF
• fever, vomiting, local tenderness and guarding
• a vague mass may be felt in LIF and rectal examination
• pericolic abscess: tender mass a/w swinging fever and leucocytosis

Question 6

Hinchey Classification of acute diverticulitis

Answer 6

• Grade I: mesenteric or pericolic abscess
• Grade II: pelvic abscess
• Grade III: purulent peritonitis
• Grade IV: faecal peritonitis

Question 7

Chronic diverticular disease

Answer 7

• change in bowel habit (diarrhoea alternating with constipation)
• large bowel obstruction (vomiting, distension, colicky abdominal pain, constipation)
• blood and mucus per rectum
• tenderness in LIF and thickened mass in region of sigmoid colon

Question 8

Less common presentation of diverticular disease

Answer 8

• profuse rectal bleeding
• colovesical fistula: diverticulitis –> fistula into bladder with passage of gas bubble (penumaturia) and faecal debris in urine

Question 9

Special investigation

Answer 9

• CT: in acute stage and help exclude other causes of lower abdominal pain
• sigmoidoscopy: fibreoptic–> full visualisation of sigmoid colon
• colonoscopy: inspect the affected sigmoid colon
• CT colonography and barium enema : diverticula –> signet ring appearance due to filling defect by faecoliths, diverticular disease: stricture formation (diverticular wall thickening involve long segment, low density and smooth)

Question 10

Treatment of acute diverticulitis

Answer 10

Conservatively

• fluid diet
• antibiotics (metronidazole with penicillin and gentamicin or ciprofloxacin)

Pericolic abscess

• diagnosed by CT
• drained percutaneously
• sepsis is controlled–> laparotomy and resection of diseased segment

General peritonitis

• perforation of diverticular abscess –> laparoscopic lavage and drainage/ laparotomy–> affected segment is resected–> colostomy (Hartmann’s procedure: sigmoid colectomy–> end colostomy–> rectum oversewn/ brought to surface–> can be restored by colorectal anastomosis)
• full antibiotic therapy

Acute obstruction
- laparotomy –> affected segment of colon is resected –> end colostomy

Question 11

Treatment of chronic diverticulitar disease

Answer 11

Symptoms are mild

• lubricant laxative (Milpar)
• high-roughage diet (fruit, vegetable, wholemeal bread and bran)

Symptoms are severe
- laparotomy and resection of sigmoid colon

Colovesical fistula

• resection of affected segment of colon and bladder wall–> primary colonic anastomosis –> defect in bladder oversewn
• covering loop ileostomy