Diverticular disease Flashcards
What is diverticular disease?
Diverticula is characterised by having the presence of diverticula (small mucosal herniations) which protrude through the large intestinal wall and small muscle. Under normal physiological conditions these diverticula do not cause any problems - are asymptomatic (diverticulosis) however when they become inflammed they cause symptoms (diverticula disease) and when infected these cause symptoms of diverticulitis.
How common is diverticula disease?
Very common especially in Westernised countries due to changes in the diet.
How prevalent is diverticula disease in relation to gender?
Similar in males and females
How prevalent is diverticula disease in relation to age?
Increases with age
Rare in people aged <40 years
1/3 people >65 years, >65% people >85 yrs
What percentage of patients with diverticulum remain asymptomatic?
80-85%
What percentage of people develop diverticulitis?
About 5% patients with diverticulosis develop diverticulitis
What percentage of patients with diverticulitis need surgery?
15-20%
What is the increased risk of mortality with diverticulitis associated with?
Abscess formation (causing a passageway)
Intestinal rupture
Fistulas (inflammation/abscess causes passageway)
Peritonitis (inflammation in the lining abdominal wall and organs in abdomen such as the kidney)
Massive bleeding
Also more common in immunocompromised or on anti-inflammatories or co-morbidities
What is the cause of the formation of diverticulitis?
Causative agents are unknown but it is thought to relate to:
– Increased intraluminal pressure and weakening of muscle wall thought to be a primary cause, this relates to years of low dietary fibre which causes hypertrophy of the intestinal muscle wall. This causes an increase in pressure within the lumen
– Abnormal colonic motility (and associated conditions - IBS, use of opioids)
– Defective muscular structure
– Changes in collagen structure (ageing)
What are some of the other factors thought to be involved in diverticula development?
Genetics
* Left-sided diverticula predominate in the west (sigmoid colon)
* Right-sided predominant in Asians
Dietary factors
* Associated with a low fibre diet and constipation
* Associated with obesity
How do diverticulum form?
Years of low fibre within the diet leads to colonic muscular hypertrophy to compensate. This leads to a narrowing of the intestinal lumen.
Essentially if there is a weakness along the intestinal membrane (often at an area of dense capillaries) this can lead to a development of a small chamber with high pressure. Development of a hernia exploits the rich blood supply and subsequently diverticulum forms.
How does diverticulitis occur?
- Faecal material or undigested food collect in Diverticula and cause obstruction
- Mucus secretion and normal bacterial overgrowth lead to distension of diverticula
- Results in vascular compromise and perforations
- Increase in intraluminal pressure and stuck food particles may also damage diverticula wall, resulting in inflammation and necrosis and perforation
- Recurrent attacks lead to scar tissue formation and lumen narrowing
What is the management of diverticulosis?
Diverticulosis is when presence of the diverticula is asymptomatic and therefore there is no need for routine follow up
Emphasise having a high fibre diet (to prevent colonic muscular hypertrophy)
Advise of adequate fluid intake (prevent constipation straining)
Weight loss
Exercise
Stop smoking
Bulk forming laxative if constipated
What are some of the symptoms of diverticular disease?
- Intermittent pain in lower left quadrant (with constipation, diarrhoea, rectal bleeds)
- Abdominal pain worsened by eating, relieved by passing stool or wind
- Flatulence
- Lower left quadrant tenderness on palpation but may present on the right in Asian populations
- Symptom overlap with IBD
- No systemic symptoms
When is diverticular disease diagnosed?
Will often not be diagnosed until imaging/routine colonscopy due to symptom overlap with IBS
