Diverticulitis

Overview

Diverticulitis occurs when small pouches (diverticula) that can form in the wall of the colon become inflamed or infected. Most people with diverticula have no symptoms (diverticulosis), but in some the pouches become inflamed, causing pain, fever, and bowel changes.

How common is it?

Diverticulosis (having the pouches without symptoms) affects about half of people over 60 in Western countries. About 1 in 4 with diverticulosis will develop diverticulitis at some point.

Causes and risk factors

Increased pressure inside the colon, often from a low-fibre diet leading to hard stools and straining, is thought to cause the bowel wall to bulge outward. Diverticulitis occurs when these pouches become blocked and inflamed.

Common risk factors

• Low dietary fibre intake
• Age over 40
• Obesity
• Physical inactivity
• Red meat consumption
• Smoking
• Use of NSAIDs and steroids
• Constipation

Symptoms

• Sudden, often severe pain in the lower left abdomen
• Fever and chills
• Nausea and vomiting
• Change in bowel habit (constipation or diarrhoea)
• Tenderness over the affected area
• Blood in stools (uncommon in uncomplicated cases)

When to see a doctor

Go to hospital for severe abdominal pain with fever, especially if the abdomen becomes rigid (suggesting perforation). See a doctor promptly for a first episode of significant lower abdominal pain.

Diagnosis

CT scan with contrast is the preferred investigation. It confirms diagnosis, grades severity, and identifies complications such as abscess or perforation. Blood tests show infection markers.

Treatments

Self-care and lifestyle

• Increase dietary fibre gradually after recovery to prevent recurrence
• Maintain adequate hydration
• Exercise regularly to maintain bowel transit
• Avoid prolonged constipation

Prevention

High-fibre diet, plenty of water, regular exercise, and maintaining healthy weight reduce the risk of diverticulosis developing and of diverticulitis episodes.