What is the treatment for diverticulitis?

Treatment of Diverticulitis

For uncomplicated diverticulitis, antibiotics should be avoided in immunocompetent patients as they neither accelerate recovery nor prevent complications or recurrence. 1, 2

Classification and Diagnosis

• Diverticulitis is classified as either uncomplicated (localized inflammation without abscess or perforation) or complicated (involving abscess, perforation, fistula, or obstruction) 2, 3
• CT scan is the gold standard for diagnosis with 98-99% sensitivity and 99-100% specificity, showing diverticula, wall thickening, and increased density of pericolic fat 4
• Approximately 85% of acute diverticulitis cases are uncomplicated 4

Treatment Algorithm for Uncomplicated Diverticulitis

First-Line Management (No Antibiotics)

• Conservative treatment without antibiotics is recommended for uncomplicated diverticulitis in immunocompetent patients 1, 2
• Management should focus on supportive care with clear liquid diet during the acute phase, advancing as symptoms improve 3
• Pain control with acetaminophen is typically sufficient 4
• Re-evaluation within 7 days is recommended, with earlier follow-up if clinical condition deteriorates 5, 3

When to Use Antibiotics in Uncomplicated Diverticulitis

Antibiotics should be reserved for patients with:

• Immunocompromised status (receiving chemotherapy, high-dose steroids, post-transplant) 2, 5
• Systemic manifestations of infection (persistent fever, chills) 5, 4
• Increasing leukocytosis or WBC >15 × 10^9/L 5, 3
• Advanced age (>80 years) 3, 4
• Significant comorbidities (cirrhosis, chronic kidney disease, heart failure, poorly controlled diabetes) 5, 4
• CRP >140 mg/L 5, 3
• Longer segment of inflammation or fluid collection on CT 5, 3
• Symptoms lasting >5 days 5

Antibiotic Selection When Indicated

• Oral regimens (preferred whenever possible) 3:
  • Amoxicillin-clavulanate 5, 4
  • Ciprofloxacin plus metronidazole 5, 6
• Intravenous regimens (for those unable to tolerate oral intake) 5:
  • Ceftriaxone plus metronidazole 4
  • Ampicillin-sulbactam 4
  • Piperacillin-tazobactam (for severe cases) 5, 4
• Duration: 4-7 days for immunocompetent patients; 10-14 days for immunocompromised patients 5, 3

Treatment of Complicated Diverticulitis

• For small abscesses (<4-5 cm), antibiotic therapy alone for 7 days 1, 3
• For large abscesses (>4-5 cm), percutaneous drainage combined with antibiotic therapy 1, 3
• Surgical intervention if clinical deterioration occurs or for generalized peritonitis 1, 4

Outpatient vs. Inpatient Management

Outpatient Management Criteria

• Uncomplicated diverticulitis 3, 6
• Ability to tolerate oral intake 5, 6
• No significant comorbidities 5, 6
• Adequate family support 6
• Absence of severe pain or systemic symptoms 3, 7

Inpatient Management Criteria

• Complicated diverticulitis 3
• Significant comorbidities 3, 7
• Inability to tolerate oral intake 5, 3
• Severe pain or systemic symptoms 3
• Lack of adequate support at home 6

Prevention of Recurrence

• High-quality diet high in fiber from fruits, vegetables, whole grains, and legumes 5
• Regular physical activity 5
• Achieving or maintaining normal body mass index 5
• Avoiding smoking 5
• Avoiding regular use of NSAIDs and opiates when possible 5

Common Pitfalls to Avoid

• Overuse of antibiotics in uncomplicated cases without risk factors contributes to antibiotic resistance without providing clinical benefit 2, 3
• Failure to recognize high-risk patients who would benefit from antibiotics despite mild presentation 2, 3
• Unnecessarily restricting consumption of nuts, corn, popcorn, or small-seeded fruits, as they are not associated with increased risk of diverticulitis 5
• Inadequate follow-up to ensure resolution of symptoms 2
• Missing signs of progression to complicated diverticulitis 2, 5