Patient information from BMJ

Diverticular disease

Last published:Jul 14, 2020

Diverticular disease is a common condition that can lead to painful cramps in your abdomen. Eating more fibre can sometimes help. There are also treatments that can improve your symptoms.

What happens?

Lots of people have small pouches of tissue that bulge outwards from their gut wall. Doctors call these pouches diverticula. If you get symptoms because of these pouches, your doctor may say you have diverticular disease.

If these pouches become inflamed or infected, this is called diverticulitis. Sometimes diverticulitis can lead to more serious problems, such as a hole in your bowel or a blockage that stops you passing stools.

Diverticula are a bit like an inner tube that pokes through weak places in a tyre. You can have just one of these pouches. But most people with diverticular disease have more than one. Some people have hundreds.

Although you can sometimes get these pouches in other places, such as your stomach, here we look only at diverticula in the last part of your large bowel (your colon). You may hear this called colonic diverticular disease.

No one knows exactly why people get diverticula. But you may be more likely to get them if you don't eat enough fibre. Fibre is the part of fruits, vegetables, and grains that your body can't digest.

What are the symptoms?

Most people with diverticula don't know they have these pouches, as they don't usually cause problems. Many people only find out they have diverticula when they're having tests for other conditions that affect their bowel.

When diverticula do cause symptoms, the most common problems are painful cramps in the lower part of the abdomen, usually on the left side.

The pain may come and go, or it may be constant. It often starts after you've had a meal and gets better when you pass wind or a stool. Other symptoms include:

• bloating

• constipation or diarrhoea

• blood in your stool. The bleeding may be heavy. If you see blood in your stool you should see your doctor straight away, as this can also be a sign of a more serious condition.

If one or more of these pouches become inflamed or infected (called diverticulitis), you may get other symptoms, such as:

• severe and constant pain in your lower abdomen, probably on your left side

• a high temperature (fever)

• nausea and vomiting.

The symptoms of diverticular disease and diverticulitis can resemble the symptoms of many other conditions. Your doctor will examine you and may test your blood for signs of inflammation and infection.

Depending on your symptoms, you may have other tests as well, such as a CT scan (a type of X-ray) or a colonoscopy. During a colonoscopy, doctors use a thin, flexible tube with a light and camera at the end to look at the inside of your colon.

What treatments work?

If your diverticula aren't causing problems

If you find out you have diverticula during tests for another condition and you don't have any symptoms, then you don't need any treatment. Your doctor may simply suggest that you eat plenty of high-fibre food, such as fruits and vegetables.

If your diverticula are causing mild symptoms

If your diverticula are causing mild symptoms, such as some cramping, your doctor will probably recommend:

• adding more fibre to your diet. This could involve eating more high-fibre foods and possibly taking a fibre supplement. You should also drink plenty of fluids.

• taking a course of antibiotics - if your doctor thinks you may have an infection.

If you have diverticulitis

If your diverticula are inflamed or infected, your doctor will recommend:

• taking antibiotics. You will probably take antibiotic tablets for a few days. If you don't improve, you will probably need treatment in hospital with antibiotics through a drip (an intravenous infusion or IV).

• taking painkillers to cope with any discomfort. These may be over-the-counter pain medicines, such as paracetamol, or stronger medicines that require a prescription.

• following a 'low residue diet' until your symptoms improve. This means eating foods that are easily digested and absorbed, leaving little to pass out of your body in stools. Examples include white bread, white rice, vegetable and fruit juice without pulp, and dairy products. These are all low-fibre foods.

If you have complications from diverticulitis

Diverticulitis can sometimes lead to other problems (complications), such as

• heavy bleeding

• a sac of infected pus (an abscess) forming in the bowel

• a blockage in the bowel, or

• an abnormal opening (called a fistula) forming between the bowel and another organ (such as the bladder).

These complications may require surgery to remove the affected part of bowel. However, sometimes other treatments can help. For example, a small abscess can sometimes be treated with antibiotics and a larger abscess can be drained.

What will happen to me?

Your symptoms may be mild and you may have long periods when you don’t have any problems. Or, your condition may be more severe, with symptoms almost constantly.

If you have had diverticulitis and recovered without having surgery, you have about a 1 in 3 chance of having another attack within five years. Second attacks are usually more serious than first attacks and are harder to treat.

If you get repeated attacks, your doctor may suggest you have surgery to remove the affected part of your bowel. This will help prevent more attacks.