What is the recommended treatment for diverticulitis?

Treatment of Diverticulitis

Most patients with acute uncomplicated left-sided colonic diverticulitis should be managed in an outpatient setting with observation, pain control, and dietary modification, with selective use of antibiotics only for specific high-risk patients. 1

Classification and Diagnosis

• Diagnostic Test: CT scan with IV contrast is the recommended diagnostic test with 98-99% sensitivity and 99% specificity 1, 2
• Alternative Imaging: Ultrasound or MRI when CT with contrast is contraindicated 1

Treatment Algorithm for Diverticulitis

Uncomplicated Diverticulitis (85% of cases) 2

1. First-line management:

   • Observation
   • Pain management (typically acetaminophen)
   • Dietary modification with clear liquid diet
   • Outpatient management for most patients 1

2. Antibiotic therapy - Reserved only for high-risk patients:

   • Patients with systemic symptoms (persistent fever/chills)
   • Increasing leukocytosis
   • Age >80 years
   • Pregnant patients
   • Immunocompromised patients (on chemotherapy, high-dose steroids, organ transplant recipients)
   • Patients with chronic medical conditions (cirrhosis, CKD, heart failure, poorly controlled diabetes) 1, 2

3. Antibiotic options for uncomplicated cases:

   • Oral regimens:
     • Amoxicillin/clavulanic acid or
     • Cefalexin with metronidazole or
     • Ciprofloxacin with metronidazole 2, 3, 4
   • Duration: 7-10 days 3, 4

Complicated Diverticulitis

1. Intravenous antibiotics:

   • Single-agent options: Piperacillin-tazobactam, ertapenem, meropenem, or imipenem/cilastatin
   • Combination therapy: Ceftriaxone + metronidazole, ciprofloxacin + metronidazole, or ampicillin + gentamicin + metronidazole 1, 2
   • Duration: 4-7 days 1

2. Additional interventions:

   • Percutaneous drainage for abscesses
   • Surgical intervention for:
     • Diffuse peritonitis
     • Persistent symptoms despite drainage
     • Failure of medical therapy with worsening inflammatory signs 1

Surgical Management When Indicated

• Stable patients: Primary resection and anastomosis (with/without diverting stoma)
• Unstable/high-risk patients: Hartmann's procedure
• Severe hemodynamic instability: Consider damage control procedure 1

Contraindications for Outpatient Management

• Suspected complicated diverticulitis
• Recent antibiotic use
• Unstable comorbid conditions
• Immunosuppression
• Signs of sepsis
• Inability to tolerate oral intake
• Inadequate family/social support 1

Evidence on Antibiotic Use

Recent evidence suggests that antibiotics may not be necessary for all cases of uncomplicated diverticulitis. A randomized clinical trial of 623 patients found that antibiotic treatment for acute uncomplicated diverticulitis neither accelerated recovery nor prevented complications or recurrence 5. This supports the selective use of antibiotics approach recommended in current guidelines.

Prevention of Recurrence

• High-fiber diet (fruits, vegetables, whole grains, legumes)
• Regular physical activity
• Smoking cessation
• Avoidance of NSAIDs, opiates, and corticosteroids
• Fiber supplementation may be beneficial 1

Important Considerations

• Outpatient success rate: Studies show >92% success rate for outpatient treatment of uncomplicated diverticulitis 3
• Follow-up: Plan early colonic evaluation (4-6 weeks) for patients with diverticular abscesses treated non-operatively to rule out malignancy 1
• Surgical timing: If surgery is needed, delay >60 hours increases mortality and need for relaparotomy 1

Common Pitfalls to Avoid

1. Overuse of antibiotics in uncomplicated cases without risk factors
2. Delaying surgical intervention when indicated (>60 hours increases mortality)
3. Failing to identify high-risk patients who need more aggressive management
4. Missing malignancy - ensure appropriate follow-up colonoscopy after resolution