Diverticular Disease and Diverticulitis

Question 1

What is a diverticulum? What is the pathology associated with them?

Answer 1

A herniation of bowel mucosa through the muscular layer that surrounds the intestines

• Most commonly in the sigmoid and descending colon
• The muscles they herniate through are the taeniae coli (3x bands of longitudinal smooth muscle running transversely the length of the colon, where they contract normally forms the rings/haustra that give the AXR appearance)
• C. 5-10mm (up to 2cm) in diameter

Diverticulosis:
- Presence of asymptomatic diverticula

Diverticular disease:
- Presence of symptomatic diverticula

Diverticulitis:
- Presence of diverticular inflammation +/- local signs and symptoms

Question 2

What is the epidemiology of diverticular disease?

Answer 2

Diverticulosis:

• Occurs in 5-10% of people 45yrs+ and up to 80% of people aged 85+
• 75% asymptomatic

Diverticular disease
- 25% of all people with diverticulosis, and 75% of these will have 1x episode of diverticulitis

Highest prevalence in USA, Europe and Australia

Low intake of dietary fibre is a significant risk factor

Obesity is a risk factor, especially in younger people

NSAIDs + paracetamol use and smoking are also risk factors

Question 3

How do diverticulosis and diverticular disease present?

Answer 3

Frequently incidental findings e.g. on screening for colon Ca

Non-specific abdo complaints e.g.

• Lower abdo pain, often on the left, exacerbated by eating and diminished by defecation or flatus
• Bloating, constipation, rectal bleeding…
• Fullness or mild tenderness in LLQ

Question 4

How does diverticulitis present?

Answer 4

Typically LLQ (though can be RLQ, esp in Asian patients) 
- Intermittent or constant 

Change in bowel habit

Anorexia, N+V

Fever + tachycardia

• Possible shock if perforation but rare
• Other signs of sepsis if severe

Examination:

• Localised tenderness
• Reduced/normal bowel sounds
• ?palpable mass
• DRE: tenderness or ?mass

Question 5

What are some important sequalae of diverticulitis?

Answer 5

Lower GI haemorrhage

• Usually abrupt, painless bleeding
• Possible mild lower abdo cramps, tenesmus
• Passage of red/maroon blood +/- clots
• Melaena is rare (due to location of bleed, but not impossible)
• May bleeds stop by themselves, but re-bleed c.20-40%

Partial colonic- or pseudo- obstruction may occur

Repeat episodes may cause stricture, fistula

• Colovesicular - pneumaturia, faecaluria
• Colovaginal - stool or flatus passage through vagina +/- infection or copious discharge

Question 6

How do you investigate diverticular disease?

Answer 6

Colonoscopy if symptomatic - to rule out other Dx, esp. bowel Ca

FBC to exclude infection and anaemia

Question 7

How do you investigate diverticulitis?

Answer 7

FBC- raised WCC, ?anaemia
U+E - possible abnormalities
CRP - raised

Contrast CT:
- <24hrs after admission if raised inflammatory markers (or high index of suspicion)
- Can do non-contrast/USS/
MRI if contrast contraindicated

If inflammatory markers not raised:

• ?Fistula - cystoscopy may be useful
• ?haemorrhage - flexi sig

Question 8

How do you manage diverticular disease?

Answer 8

• High fibre diet (whole grains, fruit, vegetables - may take weeks to work) + increased water intake = prophylaxis
• Bulk forming laxatives may supplement those struggling
• Smoking cessation and reduction in NSAID use
• Paracetamol for pain, antispasmodics e.g. buscopan may be useful for cramping

If bleeding has been frequent or significant and Hb is low - may need Fe supplementation or blood transfusion

Question 9

How do you manage diverticulitis? (at home, criteria for admission and hospital Mx)

Answer 9

At home:

• PO Abx if systemically unwell
• Multiple regimens e.g. 7 days coamox, or cefalexin + metronidazole
• PO paracetamol for pain
• Clear liquids only, re-introduce solid foods over 2-3 days

Admit when:

• Pain not managed with paracetamol
• Hydration cannot be maintained orally, nor PO Abx taken
• Person is frail with comorbidities
• Significant bleeding requiring transfusion
• Sx persist >48hrs despite conservative Mx at home

As an inpatient:

• IV Abx - same drugs as community or contact micro
• R/V in 48hrs and consider PO step down
• Uncomplicated pericolic abscess <3cm can be treated with Abx and bowel rest but may need CT guided drainage
• Haemorrhage may be managed acutely with vasopressin but benefit only temporary, in prep for ?angio/surg

Question 10

When is surgery indicated in diverticulitis?

Answer 10

In 15-30% of those with diverticulitis

Indications:

• Purulent or faecal peritontis
• Uncontrolled sepsis or bleeding
• Fistula
• Obstruction
• Inability to exclude Ca
• Perforation (high mortality)

Procedures:

• Primary anastomosis +/- diverting stoma OR
• Hartmann’s (resection of bowel with end stoma)