Diverticulitis: causes, symptoms, diagnosis, and management

Diverticulitis is inflammation or infection of pouches (diverticula) in the intestinal wall. This article explains causes, signs, diagnosis, treatment, prevention, and notable distinctions.

Author: Leandro Alegsa Creation date: November 13, 2022 Last updated: May 24, 2026

Overview

Diverticulitis is a condition of the digestive tract in which small bulging pouches called diverticula become inflamed or infected. These pouches most commonly develop in the colon but can appear elsewhere in the gastrointestinal tract. The term is used to describe the inflamed state; the presence of pouches without inflammation is called diverticulosis. For general context see digestive disease resources and material on the digestive system.

Causes and characteristics

Diverticula form where the inner layers of the bowel push through weak spots in the outer muscular wall. When one or more of these pouches become irritated or infected, the condition is called diverticulitis. In most adults this affects the large intestine; for more on intestinal anatomy see large intestine references. Diverticula may also be found higher in the tract, including the stomach and esophagus or the small intestine, though this is less typical. Inflammation is a key feature—medical materials often discuss the role of inflammation in causing pain and localized complications.

Symptoms and complications

Common symptoms include lower abdominal pain (often on the left side), fever, changes in bowel habits, and tenderness. Complications can include abscesses, perforation, fistula formation, or bowel obstruction. Severity ranges from mild inflammation treated without hospitalization to severe infection requiring surgery and antibiotics.

Diagnosis and treatment

Diagnosis typically relies on clinical examination and imaging, most commonly computed tomography (CT) of the abdomen, which identifies inflamed diverticula and complications. Mild cases may be managed with dietary modification, rest, and oral antibiotics; more serious cases can require intravenous antibiotics, drainage of abscesses, or surgical resection of the affected segment.

Prevention and notable points

Preventive measures emphasize a high-fiber diet, adequate fluids, and regular activity to support bowel health. Not every person with diverticula will develop diverticulitis; many remain asymptomatic. Understanding distinctions—diverticulosis versus diverticulitis, uncomplicated versus complicated disease—helps guide appropriate care and follow-up.

See also: patient education and clinical guidelines at resource links.
Anatomy references: colon, stomach/esophagus, small intestine.

Questions and Answers

Q: What is diverticulitis?

A: Diverticulitis is a disease that affects the digestive system, caused by inflammation of pouches known as diverticula located in the walls of the bowel.

Q: Where does diverticulitis usually occur?

A: Diverticulitis usually occurs in the large intestine, though diverticula can be found in the upper digestive tract level of the esophagus, stomach and small intestine.

Q: What causes diverticulitis?

A: Diverticulitis is caused by the inflammation of diverticula, which are small pouches that form in the walls of the bowel.

Q: What are the symptoms of diverticulitis?

A: The symptoms of diverticulitis include abdominal pain, fever, nausea, constipation, and diarrhea, and sometimes rectal bleeding.

Q: What makes diverticulitis more likely to occur?

A: A diet low in fiber, age, obesity, and lack of physical activity are factors that make diverticulitis more likely to occur.

Q: How is diverticulitis diagnosed?

A: A diagnosis of diverticulitis is usually made by physical examination and medical history, and sometimes with the use of CT scans, ultrasound, or blood tests.

Q: What are the treatment options for diverticulitis?

A: Treatment for diverticulitis can include antibiotics, a liquid or low-fiber diet to rest the colon, and even surgery in severe cases. Prevention can involve maintaining a healthy diet high in fiber, regular exercise, quitting smoking, and managing weight.

Author

Creation date: November 13, 2022

Last updated: May 24, 2026