Diverticular disease is a benign disease of the colon that consists of small pockets in the large bowel. It is a very common condition that increases with age. It is often an incidental finding on colonoscopy without any symptoms.

The pocket is a protrusion of the lining of the large bowel through the muscle layers. It most commonly occurs in the sigmoid colon but can occur anywhere in the large bowel.

Diverticular disease is associated with a low fibre diet and chronic constipation. Patients are often recommended to have a high fibre diet but otherwise no special diet is required. There is no evidence that seeds or nuts cause complications with diverticular disease.

Diverticular disease does not increase your risk of developing bowel cancer.

Complications of diverticular disease often cause symptoms and treatment is dependent on the nature and extent of the complication.

The pockets of diverticular disease can become inflamed and this is called diverticulitis. Patients with diverticulitis often presents with lower abdominal pain, change in bowel habits and fever. Diagnosis is often confirmed on CT scan and treated with antibiotics. Most patients can be treated as an outpatient but some may require hospitalisation. If complications such as perforation, abscess or fistula (abnormal connection between two structures) formation develops, other treatment such surgery may be required. Only a very small percentage of patients with diverticulitis would require surgery.

Following an episode of diverticulitis, most patients will require a follow up colonoscopy. This usually occurs at least 6 weeks after discharge from hospital. The aim of the colonoscopy is to confirm the presence of diverticular disease and to rule out any malignancy.

Another complication related to diverticular disease is rectal bleeding. This is due to small blood vessels in the wall of the pockets in the bowel being traumatised and bleed. Patients typically experience urge to defaecate and then pass blood via rectum without much stool. The blood is usually bright red and may contain some dark clots. The extent of bleeding varies and occasionally may be quite significant. Often, the bleeding will stop by itself without much intervention but somethings bleeding can be significantly enough to warrant intervention. Patients with significant bleeding will be initially supported with fluid resuscitation and transfusion of blood products if necessary. Interventions to stop bleeding may include angiography and embolisation, colonoscopy and surgery.

Stricture or narrowing of the large bowel due to diverticular disease is uncommon and is usually due to recurrent inflammation of the large bowel. Repeated episodes of diverticulitis may heal with scar tissue and these may cause the large bowel to narrow. Sometime the large bowel is too narrow that it causes blockage of the bowel. Diagnosis can be made on colonoscopy or imaging modality such as CT scan or barium enema. Treatment would depends on the extent and location of the stricter but would often involves surgery to remove the involved segment of the bowel.