What is the recommended treatment for diverticulitis?

Treatment of Diverticulitis

The recommended treatment for diverticulitis should be tailored based on disease severity, with antibiotics used selectively rather than routinely in immunocompetent patients with uncomplicated diverticulitis, while reserving antibiotics for complicated cases or high-risk patients. 1

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
• Complicated diverticulitis: Involves abscess formation, perforation, fistula, or obstruction 2

Treatment Algorithm for Uncomplicated Diverticulitis

First-line Management (Immunocompetent Patients)

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

When to Use Antibiotics in Uncomplicated Diverticulitis

Antibiotics should be reserved for patients with:

• Systemic manifestations of infection (persistent fever, chills) 1, 2
• Immunocompromised status 1
• Advanced age (>80 years) 2, 3
• Significant comorbidities (cirrhosis, chronic kidney disease, heart failure, poorly controlled diabetes) 2, 3
• Laboratory markers of severe inflammation (CRP >140 mg/L or WBC >15 × 10^9/L) 1, 2
• Longer segment of inflammation or fluid collection on CT 1, 2
• Pregnancy 3

Antibiotic Selection When Indicated

Outpatient Treatment

• Oral antibiotics are preferred whenever possible 1, 4
• First-line options:
  • Amoxicillin-clavulanic acid 3, 5
  • Ciprofloxacin plus metronidazole 6, 5
• Duration: 4-7 days for immunocompetent patients 1

Inpatient Treatment

• Intravenous antibiotics for patients unable to tolerate oral intake 1, 4
• Options include:
  • Ceftriaxone plus metronidazole 3
  • Piperacillin-tazobactam 3
  • Ampicillin-sulbactam 3
• Duration: 4-7 days, with transition to oral antibiotics as soon as possible 1, 2
• Extended duration (10-14 days) for immunocompromised patients 1

Treatment of Complicated Diverticulitis

• For small abscesses (<4-5 cm): Antibiotic therapy alone for 7 days 2
• For large abscesses (>4-5 cm): Percutaneous drainage combined with antibiotic therapy 2
• Surgical intervention if clinical deterioration occurs 2

Outpatient vs. Inpatient Management

Outpatient Management Criteria

• Uncomplicated diverticulitis 2, 6
• Ability to tolerate oral intake 6, 5
• Adequate pain control 2, 5
• Absence of significant comorbidities 6, 5
• Appropriate family support 5

Inpatient Management Criteria

• Complicated diverticulitis 2
• Significant comorbidities 2
• Inability to tolerate oral intake 2, 5
• Severe pain or systemic symptoms 2
• Immunocompromised status 1

Important Considerations and Pitfalls

• Failure to recognize high-risk patients who need antibiotics despite having uncomplicated disease can lead to progression to complicated diverticulitis 1, 2
• Unnecessary use of antibiotics in low-risk patients with uncomplicated diverticulitis provides no benefit and contributes to antibiotic resistance 1, 7
• Oral antibiotics are as effective as intravenous antibiotics for patients who can tolerate oral intake, with significant cost savings 6, 4, 7
• Outpatient management of uncomplicated diverticulitis is safe and effective in appropriate candidates, reducing healthcare costs by approximately €1,600 per patient 6
• Immunocompromised patients are at higher risk for complicated disease and treatment failure, requiring a lower threshold for imaging, antibiotics, and surgical consultation 1
• Follow-up colonoscopy should be considered for patients with diverticular abscesses to rule out underlying malignancy 2