What is the treatment for diverticulitis?

Treatment of Diverticulitis

For immunocompetent patients with uncomplicated diverticulitis, antibiotics should be used selectively rather than routinely, with management focusing on supportive care with clear liquid diet and pain control. 1, 2, 3

Classification of Diverticulitis

• Uncomplicated diverticulitis: Localized diverticular inflammation without abscess or perforation, typically confirmed by CT scan showing diverticula, wall thickening, and increased density of pericolic fat 2, 3
• Complicated diverticulitis: Involves abscess formation, perforation, fistula, or obstruction 3

Treatment Algorithm for Uncomplicated Diverticulitis

First-Line Management

• Clear liquid diet during the acute phase, advancing as symptoms improve 2, 3
• Pain management (typically acetaminophen) 4
• Observation without antibiotics for immunocompetent patients with mild uncomplicated diverticulitis 1, 2
• Re-evaluation within 7 days; earlier if clinical condition deteriorates 3

When to Use Antibiotics in Uncomplicated Diverticulitis

Antibiotics are indicated for patients with:

• Immunocompromised status 1, 2, 3
• Comorbidities or frailty 1, 2, 3
• Refractory symptoms or vomiting 1
• CRP >140 mg/L or WBC >15 × 10^9/L 1, 2, 3
• Fluid collection or longer segment of inflammation on CT 1, 2
• Advanced age (>80 years) 3, 4
• Pregnancy 3, 4
• Chronic medical conditions (cirrhosis, chronic kidney disease, heart failure, poorly controlled diabetes) 2, 4
• ASA score III or IV 1
• Duration of symptoms longer than 5 days prior to presentation 1

Antibiotic Selection When Indicated

• Outpatient setting: Oral amoxicillin-clavulanate or ciprofloxacin plus metronidazole for 4-7 days 1, 2, 4
• Inpatient setting: IV antibiotics with gram-negative and anaerobic coverage (ceftriaxone plus metronidazole, ampicillin-sulbactam, or piperacillin-tazobactam) 2, 4
• Duration: 4-7 days for immunocompetent patients; 10-14 days for immunocompromised patients 1, 2

Treatment of Complicated Diverticulitis

• For small abscesses (<4-5 cm): Antibiotic therapy alone for 7 days 3
• For large abscesses (>4-5 cm): Percutaneous drainage combined with antibiotic therapy 3
• After drainage of diverticular abscess: Oral step-down therapy with ciprofloxacin 500mg twice daily plus metronidazole 500mg three times daily for 4-7 days 5
• Surgical intervention if clinical deterioration occurs 3

Outpatient vs. Inpatient Management

Suitable for Outpatient Management

• Uncomplicated diverticulitis 2, 3, 6
• Ability to tolerate oral intake 3
• Adequate pain control 3
• Absence of significant comorbidities 3

Requiring Inpatient Management

• Complicated diverticulitis 3
• Significant comorbidities 3
• Inability to tolerate oral intake 3
• Severe pain or systemic symptoms 3
• Immunocompromised status 1, 2

Prevention of Recurrence

• High-quality diet (high in fiber from fruits, vegetables, whole grains, legumes; low in red meat and sweets) 2
• Regular physical activity, particularly vigorous exercise 2
• Achieving or maintaining normal body mass index 2
• Avoiding smoking 2
• Avoiding regular use of NSAIDs and opiates when possible 2

Important Considerations and Pitfalls

• Recent evidence suggests there is no benefit of routine antibiotics in immunocompetent patients with mild acute uncomplicated diverticulitis 1
• Unnecessary use of antibiotics in low-risk patients with uncomplicated diverticulitis provides no benefit and contributes to antibiotic resistance 1, 3
• Risk of progression to complicated diverticulitis is approximately 5% 1
• Immunocompromised patients are more likely to present with severe or complicated disease and require a lower threshold for CT imaging, antibiotic treatment, and surgical consultation 1, 2
• Corticosteroid use is a risk factor for diverticulitis and may contribute to complications including perforation 1
• Young patients (<50 years) and those with high pain scores have increased risk for complicated or recurrent diverticulitis and should be monitored more closely 3