🔘 Diverticular Disease
Understanding diverticulosis, diverticulitis, and their management
Last reviewed: February 2026
📖 Understanding Diverticular Disease
Diverticular disease is a common condition affecting the colon (large intestine), particularly the sigmoid colon (the lower left portion). It encompasses a spectrum of conditions:
- Diverticulosis: The presence of diverticula (small pouches) in the colon wall. Most people have no symptoms.
- Diverticulitis: Inflammation or infection of one or more diverticula. Causes symptoms and requires treatment.
- Diverticular bleeding: When a blood vessel in a diverticulum ruptures, causing rectal bleeding.
- Symptomatic uncomplicated diverticular disease (SUDD): Chronic abdominal symptoms without acute inflammation.
Diverticula form when weak spots in the colon wall give way under pressure, creating small bulging pouches. They are most common in the sigmoid colon where pressure is highest.
🔬 Causes & Risk Factors
How Diverticula Form
The exact cause is not fully understood, but the process involves:
- Increased pressure inside the colon (from straining, low fiber diet)
- Weakness in the colon wall (at points where blood vessels penetrate)
- Age-related changes in the colon structure
- Diverticula push through at weak points, forming pouches
Risk Factors
| Risk Factor | Effect | Notes |
|---|---|---|
| Low fiber diet | High | Leads to harder stools, more straining |
| Age | High | Risk increases significantly after age 40 |
| Western diet | Moderate | Processed foods, low fiber, high red meat |
| Obesity | Moderate | Increases risk of diverticulitis and complications |
| Lack of exercise | Moderate | Physical activity reduces risk |
| Smoking | Moderate | Increases risk of complications |
| Certain medications | Variable | NSAIDs, steroids, opioids may increase risk |
🚨 Symptoms
Diverticulosis (Usually Asymptomatic)
Most people with diverticulosis have no symptoms. When present, symptoms may include:
- Mild cramping or bloating
- Constipation or irregular bowel habits
- Often discovered incidentally during colonoscopy or CT scan
Diverticulitis Symptoms
- Abdominal pain: Usually in left lower abdomen; often constant and persistent
- Fever: Low to moderate grade
- Change in bowel habits: Constipation or diarrhea
- Nausea and vomiting
- Loss of appetite
- Abdominal tenderness: Especially in left lower quadrant
- Bloating
Symptoms of Complications
- Abscess: High fever, severe localized pain, chills
- Perforation: Severe abdominal pain, rigid abdomen, signs of shock
- Fistula: Unusual symptoms like air in urine, stool in vagina
- Bleeding: Sudden, painless, large-volume rectal bleeding (usually maroon or bright red)
🔍 Diagnosis
For Suspected Diverticulitis
- Physical examination: Abdominal tenderness, especially left lower quadrant
- Blood tests: Elevated white blood cell count, CRP
- CT scan with contrast: Gold standard for diagnosing diverticulitis and complications
CT Findings in Diverticulitis
- Thickening of the colon wall
- Inflammation of fat around the colon (fat stranding)
- Presence of diverticula
- Abscesses if complicated
- Free air if perforation present
Classification of Diverticulitis
| Grade | Findings | Treatment Approach |
|---|---|---|
| Uncomplicated | Inflammation without abscess/perforation | Usually outpatient antibiotics |
| Complicated - Small abscess | Abscess smaller than 3-4 cm | Antibiotics; may resolve without drainage |
| Complicated - Large abscess | Abscess larger than 4 cm | CT-guided drainage + antibiotics |
| Complicated - Perforation | Free air, generalized peritonitis | Emergency surgery |
| Complicated - Fistula | Abnormal connection to another organ | Usually requires surgery |
Follow-up Colonoscopy
After an episode of diverticulitis, colonoscopy is recommended 6-8 weeks later to:
- Confirm diverticulosis
- Rule out colon cancer (which can mimic diverticulitis)
- Evaluate extent of disease
💊 Treatment
Uncomplicated Diverticulitis
Many cases can be treated at home:
- Antibiotics: Typically 7-10 days of oral antibiotics (though some mild cases may be managed without antibiotics)
- Clear liquids: Initially, then gradual diet advancement
- Pain management: Acetaminophen preferred; avoid NSAIDs
- Rest
Hospitalization Required For
- Severe symptoms or high fever
- Unable to tolerate oral intake
- Signs of complicated diverticulitis on CT
- Immunocompromised patients
- Failed outpatient treatment
- Elderly or significant comorbidities
Hospital Treatment
- IV antibiotics
- IV fluids
- Bowel rest (nothing by mouth initially)
- Pain management
- CT-guided drainage if abscess present
Surgery
Surgery may be needed for:
- Emergency: Perforation with generalized peritonitis, uncontrolled sepsis
- Elective: Recurrent episodes, persistent symptoms, fistula, stricture
Surgical options include:
- Sigmoid colectomy: Removal of affected sigmoid colon with reconnection
- Hartmann's procedure: Emergency removal with temporary colostomy
- Laparoscopic approach: Minimally invasive when possible
🥗 Diet & Prevention
High-Fiber Diet
A high-fiber diet is the cornerstone of preventing diverticulosis progression and diverticulitis:
- Goal: 25-35 grams of fiber per day
- Increase gradually: To avoid bloating and gas
- Drink plenty of water: Fiber needs fluid to work properly
High-Fiber Foods
| Food Category | Examples | Fiber Content |
|---|---|---|
| Whole grains | Oats, brown rice, whole wheat, jowar, bajra | High |
| Legumes | Lentils (dal), chickpeas, beans, rajma | Very high |
| Vegetables | Broccoli, carrots, spinach, drumstick | Moderate-High |
| Fruits | Apples, pears, berries, guava, papaya | Moderate |
| Nuts and seeds | Almonds, chia seeds, flaxseeds | High |
Diet Myths Debunked
No! The old advice to avoid nuts, seeds, and popcorn has been disproven by research. These foods do not increase the risk of diverticulitis and may actually be beneficial due to their fiber content.
Popcorn is safe and a good source of fiber. Corn is also fine. There is no scientific evidence that these foods cause diverticulitis or get "stuck" in diverticula.
Other Prevention Strategies
- Regular exercise: At least 30 minutes most days
- Maintain healthy weight
- Don't ignore the urge: Use the bathroom when you need to
- Quit smoking
- Limit red meat: High consumption may increase risk
- Avoid NSAIDs when possible: May increase complication risk
🩸 Diverticular Bleeding
Diverticular bleeding is the most common cause of significant lower GI bleeding in adults.
Characteristics
- Sudden onset, painless rectal bleeding
- Usually large volume (maroon or bright red blood)
- Typically self-limited (stops on its own in 70-80% of cases)
- Risk of recurrence about 25%
Management
- Hospitalization for monitoring and IV fluids
- Blood transfusion if significant blood loss
- Colonoscopy once bleeding slows to identify and treat source
- Angiography and embolization if bleeding continues
- Surgery if other methods fail
❓ Frequently Asked Questions
Once diverticula form, they do not go away. However, you can prevent new ones from forming and reduce the risk of diverticulitis through a high-fiber diet and healthy lifestyle.
After one episode of diverticulitis, about 20-30% of people will have another episode. However, with proper diet and lifestyle measures, recurrence can often be prevented.
There is some genetic component, with increased risk if family members have the condition. However, diet and lifestyle factors play a larger role than genetics.
Surgery is considered for emergency complications (perforation, uncontrolled infection), recurrent episodes significantly affecting quality of life, fistulas, or strictures causing obstruction. The decision is individualized.