Diverticula are small pouches in the wall of the large bowel — very common with age and usually without symptoms (diverticulosis). When they become inflamed or infected, diverticulitis develops, typically with pain in the lower left abdomen, often with fever. Simple, uncomplicated disease is usually managed conservatively (rest, diet and, in selected cases, antibiotics). Complications (abscess, perforation) or recurrent disease may need surgery. After the acute episode, a colonoscopy is usually recommended to confirm the diagnosis and rule out other causes.
Diverticular disease is one of the most common conditions of the large bowel, especially after age 50 — and often a source of confusion, because having diverticula is not the same as having diverticulitis. Let's clear that up.
What are diverticula and diverticulitis
Diverticula are small pouches that bulge out from the wall of the large bowel (most often in the sigmoid colon). Simply having them is called diverticulosis and is very common with age, usually with no symptoms at all. When one or more diverticula become inflamed or infected, the result is diverticulitis.
Symptoms
- Pain — typically in the lower left abdomen, persistent.
- Fever and a feeling of fatigue.
- Change in bowel habits (diarrhoea or constipation), bloating.
- Sometimes bleeding (diverticular bleeding) — see also "blood in the stool".
When it's urgent
See a doctor promptly if you have severe or worsening pain, a high fever with chills, an inability to pass gas or stool, persistent vomiting or significant bleeding. These may indicate a complication (abscess, perforation) that needs immediate assessment.
Diagnosis
In the acute episode, a CT scan is the test of choice, because it confirms the diagnosis and shows any complications. Colonoscopy is avoided in the acute phase but recommended later — once the inflammation has settled — to rule out other causes such as cancer.
Treatment
Uncomplicated diverticulitis. In most cases it is managed conservatively: resting the bowel with a graded diet (from clear liquids towards normal food), adequate hydration and — in selected cases — antibiotics. According to current evidence, antibiotics are not always needed in mild disease.
Complicated disease. An abscess may need drainage, while perforation with peritonitis is a surgical emergency.
Planned surgery. In recurrent or complicated disease, planned removal of the affected segment (usually a sigmoidectomy) may be advised, which today is often performed laparoscopically or robotically with small incisions and faster recovery. The decision is individualised.
Prevention and lifestyle
A diet rich in fibre (fruit, vegetables, legumes, whole-grain products), good hydration, regular physical activity, maintaining a healthy weight and not smoking all help. These reduce the risk of episodes and recurrences.
Recovery after surgery
When planned surgery is needed, the minimally invasive approach usually allows faster mobilisation and return to activities. The exact time is individualised. See the full page on diverticular disease and the services.
What is the difference between diverticula and diverticulitis?
Diverticula are small pouches in the wall of the large bowel (diverticulosis) — very common and usually without symptoms. Diverticulitis is the term for inflammation or infection of these pouches.
What are the symptoms?
Most commonly, pain in the lower left abdomen, often with fever and a change in bowel habits. Sometimes there may also be bleeding.
Does it always need surgery?
No. Uncomplicated diverticulitis is usually managed conservatively (rest, diet and, in selected cases, antibiotics). Surgery is for complications (abscess, perforation) or recurrent disease, and the decision is individualised.
Should I avoid nuts and seeds?
No. This old advice is outdated; current evidence does not support avoiding nuts, seeds or popcorn. A diet rich in fibre is generally beneficial once the acute inflammation has settled.
Is a colonoscopy needed after the episode?
Usually yes, after the acute phase has settled, to confirm the diagnosis and rule out other causes such as cancer. The exact timing is individualised.