Diverticular Disease

Diverticular disease is a non-cancerous condition that affects the wall of the large bowel (colon). It’s also known as diverticulosis. 

If you have diverticular disease, small out-pouches (diverticula) bulge through the wall of the bowel. It mostly tends to involve a section of the left side of the large bowel, called the sigmoid colon. 

In Australia, around 60% of 60-year-olds have the condition, making it very common. While it’s certainly more common in older people, it is possible for those much younger to be diagnosed with it. 

The biggest risk factor for developing diverticular disease is low fibre intake. 

This is because a low fibre diet results in smaller, harder stool that’s more difficult, and takes a longer time, to push out. This generates extra pressure on the bowel. Over time, it’s this extra pressure that can lead to “blow-outs” and the formation of diverticulum. 

Most people who have diverticular disease do not have any discomfort or symptoms.  It’s mostly a coincidental, harmless find during a colonoscopy. 

If diverticula become inflamed or infected, this is called diverticulitis. 

Symptoms of diverticulitis are typically lower abdominal pain, often on the left side, with a fever. A CT scan is often needed to diagnose diverticulitis and look for complications.

Diverticulitis can create complications such as abscess formation, and an abnormal connection between the affected area and a neighbouring part of the body such as the bladder or vagina. This is called a fistula. 

Repeated attacks of diverticulitis can scar the colon. This causes narrowing, and on rare occasions, leads to a bowel obstruction.

In most cases, diverticulitis is easily treated with oral antibiotics. Mild attacks can occasionally be managed by resting the bowel with a liquid diet, instead of taking antibiotics.

Severe cases of diverticulitis require an admission to hospital for antibiotics through an intravenous drip.  

Yes. Once you have had an attack of diverticulitis there is a roughly 20-25% chance you will have another one.  

The risk of another attack is higher if you are male, have a family history of diverticulitis, are obese and blood tests show high inflammatory markers. 

Guidelines do recommend you get a colonoscopy after an attack of diverticulitis, unless you have had one recently.  This is to confirm the diagnosis, and to exclude other rare possibilities such as colon cancer.

Surgery is not needed if you have no symptoms, or have infrequent, mild attacks of diverticulitis.

Elective surgery might be a good option if you have had recurrent attacks of diverticulitis, or if you’ve had a single attack with complications such as an abscess or fistula. Surgery would involve removing the affected part of the sigmoid colon, then joining the two ends back together. 

In very rare occasions, a severe attack of perforated diverticulitis will need emergency surgery. In these cases, the bowl is brought out to the skin in a stoma or bag for safety reasons. This is usually temporary and another operation is performed at a later date to join the two ends back together.