Content provided by Jon Lund
Clinical Associate Professor, School of Graduate Entry Medicine & Health University of Nottingham

Diverticular Disease

1. Definitions
1.1 Diverticulum

A diverticulum is an abnormal outpouching of a hollow viscus into the surrounding tissues.
In regards to diverticulum of the colon, these are abnormal outpouchings of mucosa and submucosa through the muscle wall of the colon. These can be true or false diverticula.
1.1.1 True Diverticula
A diverticulum that contains all the layers of the wall of the viscus from which it protrudes e.g. Meckel's diverticulum, bladder diverticulum.
1.1.2 False Diverticula
A diverticulum that contain only some of the layers of the wall of the viscus
1.2 Diverticulosis
This is the condition of having diverticula in the large bowel, most commonly found in the sigmoid colon.
1.3 Diverticulitis
This condition develops from pre-existing diverticulosis, and results when diverticula become inflamed.
 
2. Epidemiology
 Incidence increases with age
Common in developed countries and uncommon in Africa and Asia
Left sided disease common in the West, right sided more common in Africa and Asia
5% affected in their 5th decade of life
50% affected by their 9th decade of life
 
3. Aetiology
Old age
Low fibre diet
Constipation
Obesity
High fibre diet + plenty of exercise = reduced risk of diverticulosis!
 
4. Pathophysiology

It is an acquired condition
Mucosa and submucosa herniates through the circular muscle layer at weak points in the wall.
Diverticula are thought to develop due to raised intraluminal pressure secondary to a low fibre diet and constipation.
Low fibre diet increases the frequency and intensity of colonic contractions leading to increases in intraluminal pressure
 
5. Complications of diverticulosis

Diverticulitis
Abscess formation
Strictures
Bleeding
Perforation
Peritonitis
Sepsis
Fistula
 
6. Symptoms

Majority of people remain asymptomatic
See the links at the bottom of the page to read patient experiences of diverticular disease

6.1 Diverticulosis

PR bleeding -
painless pr bleeding
due to erosion of a vessel at the base of the diverticulum
most frequent cause of pr bleeding in the elderly
classically co-existing inflammation is absent
can be severe and required hospitalisation
Bloating
Abdominal pain - colicky in nature
Change of bowel habit - diarrhoea/constipation

6.2 Diverticulitis
Abdominal pain - typically left sided
Fever
Constipation

6.3 Abscess

Abdominal pain
Swinging pyrexia

6.4 Fistula
Most common is a colo-vesical fistula
Recurrent UTI's
Pneumaturia
 
7. Diagnosis

History and examination
Bloods - should all be normal in uncomplicated diverticulosis
Typically a leucocytosis is seen in diverticulitis

7.1 Diverticulosis
7.1.1 Colonoscopy

Colonoscopy is the most useful test
It demonstrates diverticulae, mucosal inflammation, and most importantly excludes other pathology i.e. malignancy
Should be performed when patient is asymptomatic i.e. no acute symptoms are present
After an acute attack, should be performed 4-6 weeks post-discharge

7.1.2 Barium Enema
Contraindicated during acute episode
7.1.3 Computed Tomography Colonography
Role is still evolving
 
7.2 Diverticulitis + Other complications
7.2.1 Computed Tomography (CT)

With oral and intravenous contrast
Investigation of choice in acute episode
Can be used as a diagnostic and therapeutic tool
 
Diagnostic
Able to demonstrate the extent of inflammation, abscess formation and visualise fistulas
Therapeutic
CT guided percutaneous drainage can be performed on localised pericolic diverticular abscesses
 
8. Management
8.1 Conservative
8.1.1 Asymptomatic diverticulosis

No treatment is required
Dietary advice
increase fibre + vegetables in diet
increase fluid intake
Avoidance of constipation + constipating drugs
8.1.2 Diverticulitis
Nil by mouth (bowel rest)
IV Antibiotics (Cef & Met)
8.1.3 Pericolic Abscess
Nil by mouth
IV Antibiotics
Can be treated by CT guided percutaneous drainage
 
8.2 Surgical
8.2.1 Emergency
8.2.1.1 Indications

Peritonitis - usually secondary to either
perforated diverticulum leading to faecal peritonitis
pericolic abscess leading to purulent peritonitis
Pericolic abscess unresponsive to conservative management and not possible for percutaneous drainage

8.2.1.2 Hartmann's
This is the operation of choice for emergency left sided complicated diverticulitis
The diseased segment of bowel is removed and an end colostomy is formed
In the presence of sepsis, primary anastomosis is not possible due to the increased risk of anastomotic leak post-op
A temporary end colostomy is formed which will be reversed 3-6 months later once the patient has made a full recovery
 
8.2.2 Elective
8.2.2.1 Indications

All colonic fistulae
Recurrent attacks of diverticulitis
Strictures - leading to symptoms of sub-acute obstruction

8.2.2.2 Colonic resection + primary anastomosis
As sepsis is generally absent in the elective setting the operation of choice would be a colonic resection of the diseased segment of colon with primary anastomosis
 
9. Resources
National Organisation for Diverticular Disease - patient experiences
http://www.diverticulitis.org.uk/diverticulitis-stories.htm