What is the recommended treatment for simple diverticulitis?

Treatment of Simple Diverticulitis

For immunocompetent patients with uncomplicated diverticulitis without signs of systemic inflammation, antibiotics are not recommended as first-line therapy. 1

Diagnosis and Classification

• CT scan is the gold standard for diagnosing diverticulitis, with findings including intestinal wall thickening, signs of inflammation in the pericolonic fat, and thickening of the lateroconal fascia 2
• Uncomplicated diverticulitis is defined as localized diverticular inflammation without any abscess or perforation 1
• CT can detect signs of intestinal perforation or abscess in complicated cases 2

Treatment Algorithm for Uncomplicated Diverticulitis

First-Line Approach for Most Patients

• Observation with pain management (typically acetaminophen) and dietary modification with a clear liquid diet 3
• Outpatient management is appropriate for patients who can take fluids orally, have no significant comorbidities, and have adequate family support 4

When Antibiotics Are Indicated

Antibiotics should be reserved for patients with:

• Immunocompromised status 1, 4
• Systemic manifestations of infection (persistent fever, chills) 4, 3
• Increasing leukocytosis 3
• Age >80 years 3
• Pregnancy 3
• Chronic medical conditions (cirrhosis, chronic kidney disease, heart failure, poorly controlled diabetes) 3
• ASA score III or IV 2
• Symptoms longer than 5 days 2
• Presence of vomiting 2
• CRP >140 mg/L 2
• White blood cell count >15 × 10^9 cells per liter 1, 2
• Presence of a fluid collection or longer segment of inflammation on baseline CT (86 mm versus 65mm) 1

Antibiotic Regimens When Indicated

• Outpatient setting:

  • Oral ciprofloxacin 500 mg twice daily plus metronidazole 500 mg three times daily for 7-10 days 4
  • Alternative: oral amoxicillin-clavulanate 1, 3
  • Duration: typically 4-7 days 1

• Inpatient setting (for more severe cases):

  • IV antibiotics with gram-negative and anaerobic coverage 1
  • Options include:
    • Ciprofloxacin 400mg IV q12h plus metronidazole 5
    • Ceftriaxone plus metronidazole 3
    • Piperacillin/tazobactam 4g/0.5g q6h (for critically ill patients) 5
  • Duration: 4 days for immunocompetent, non-critically ill patients; up to 7 days for immunocompromised or critically ill patients 5

Special Considerations

Immunocompromised Patients

• Lower threshold for CT imaging, antibiotic treatment, and surgical consultation 1
• May present with milder signs and symptoms compared to immunocompetent patients 1
• Require longer duration of antibiotic treatment (10-14 days) 1
• After recovery, should consult with a colorectal surgeon to discuss elective resection 1

Monitoring Response

• Patients with inadequate response after 7 days warrant further diagnostic investigation 5, 4
• Monitor white blood cell count, C-reactive protein, and procalcitonin to assess response 5
• Follow-up CT may be needed for patients not improving on current therapy 5

Prevention of Recurrence

• High-quality diet (high in fiber from fruits, vegetables, whole grains, legumes; low in red meat and sweets) 1
• Achieve or maintain normal body mass index 1
• Regular physical activity, particularly vigorous activity 1
• Avoid smoking 1
• Note that approximately 50% of diverticulitis risk is attributable to genetic factors 1

Common Pitfalls to Avoid

• Overuse of antibiotics in uncomplicated cases without risk factors 1, 4
• Assuming antibiotics are needed for all cases of diverticulitis 2
• Restricting consumption of nuts, corn, popcorn, or small-seeded fruits (not associated with increased risk) 1
• Using fiber supplements as a replacement for a high-quality diet 1