Diverticulosis—the presence of diverticula that are asymptomatic
Diverticular disease—diverticula associated with symptoms
Diverticulitis—evidence of diverticular inflammation (fever, tachycardia) with or without localised symptoms and signs (LIF pain). Normally caused by gram negative bacteria.
Complicated diverticulitis—perforation*, abscess, fistula, stricture/obstruction
Diverticulitis affects over half of the population over 65years, with a prevalence that increases with age. You can get diverticulitis in young people.
85% of colonic diverticulitis will recover with treatment but some patients may have complications such as abscesses, fistulas, obstruction and perforation.
Recurrent diverticulitis is observed in 7-42% of people with diverticular disease and there is a 3% yearly risk of a further attack following resolution of the initial episode.
The pathogenesis incompletely understood. Inverse relationship between incidence and fibre content of the diet.
Once diverticula have formed, stool may become thickens within the neck. In a process similar to appendicitis, the obstructing faecalith promotes secretion of mucus and bacterial overgrowth, which distends and erodes the thin walled diverticulum. Localised ischaemia develops, enabling translocation of mucosal bacteria and eventual perforation.
Diverticulosis is the most common structural abnormality of the colon and in the Western world. It affects 5% of people in their fifth decade and up to 50% of those older than 80.
Diverticula arise mainly in the distal colon, with 90% of patients having sigmoid colon involvement compared with only 15% on the right side. In contrast, Asian populations show predominantly right sided involvement, this may have a genetic involvement
Colicky abdominal pain, normally left sided.
You can get a meckel's diverticulitis which causes right sided pain.
Patients get bloating, or flatulence, which is exacerbated by eating and relieved by passage of flatus or stool.
There is usually little to find on clinical examination of patients with diverticulosis.
- Diverticular disease mild left iliac fossa tenderness.
- Acute diverticulitis typically left iliac fossa tenderness + general signs of infection
- Remember coeliac disease can cause diarrhoea and may be associated with other conditions such as dermatitis herpetiformis - this is an itchy vesicular rash on the extensor surfaces of the arms and legs
Hinchey classification of acute diverticulitis:
stage 1a - phlegmon
stage 1b - diverticulitis with pericolic or mesenteric abscess
stage 2 - diverticulitis with walled off pelvic abscess
stage 3 - diverticulitis with generalised purulent peritonitis
stage 4 - diverticulitis with generalised faecal peritonitis
CT as good as USS but has slightly higher diagnostic accuracy. CT should be done in critically unwell patient without delay to rule out complicatied diverticulitis.
TreatmentUncomplicated diverticulitis might be treated as outpatient if:
- can tolerate POs
- no significant co-morbidities
- able to obtain antibiotics
- have adequate pain control
- access to follow up and social support
The role of antibiotics is controversial. One small study suggests diverticulitis might be a self-limiting process rather than one that requires antibiotics?
- High fibre diet
- Laxatives (controversial evidence)