Diverticulosis develops when small pouches form in the walls of the large intestine or colon, trapping undigested food or waste and leading to inflammation or infection.  


Diverticulitis is caused by inflammation or a small tear in a diverticulum, often the result of high or abnormal pressure in the colon. If the tear is large, stool in the colon can spill into the abdominal cavity, causing infection or inflammation.

Risk Factors

Diverticulitis is very common, affecting more than half of Americans over age 60. Risk factors include:
  • Older age
  • Low-fiber diet


  • Abdominal pain (typically in left lower abdomen)
  • Chills or fever
  • Nausea or vomiting
  • Weight loss

Diagnostic Tests

  • Abdominal palpation
  • CT scan
  • High white blood cell count


Acute diverticulitis is treated with antibiotics and after the infection has improved, eating high-fiber foods and using bulk additives like psyllium may help reduce the risk of reoccurrence. The involved portion of the colon may need to be removed for patients with:
  • Abscess
  • Hole (perforation) in the colon
  • Fistula (abnormal connections between different parts of the colon or the colon and another body area)
  • Repeated attacks of diverticulitis