What is the recommended treatment for diverticulitis?

Treatment of Diverticulitis

For immunocompetent patients with uncomplicated diverticulitis without signs of systemic inflammation, observation with pain management and dietary modification is recommended rather than antibiotics, as antibiotics do not improve outcomes. 1

Diagnosis

• CT scan with IV contrast is the recommended diagnostic test (sensitivity 98-99%, specificity 99%)
• Alternative imaging options for patients with contraindications to contrast:
  • Ultrasound
  • MRI
  • CT scan without contrast 1
• Laboratory markers:
  • Increased white blood cell count
  • Leukocyte shift to left (>75%)
  • Elevated C-reactive protein
  • Procalcitonin 1

Treatment Algorithm

Uncomplicated Diverticulitis (85% of cases)

1. First-line approach: Observation with pain management and dietary modification

   • Pain control: Typically acetaminophen 2
   • Diet: Clear liquid diet initially 1, 2
   • Avoid antibiotics in immunocompetent patients without systemic inflammation 1, 3

2. Reserve antibiotics only for:

   • Immunocompromised patients (transplant recipients, patients on chronic corticosteroids or chemotherapy)
   • Patients with persistent fever or chills
   • Increasing leukocytosis
   • Age >80 years
   • Pregnant patients
   • Patients with chronic medical conditions (cirrhosis, chronic kidney disease, heart failure, poorly controlled diabetes) 1, 2

3. Antibiotic options when indicated:

   • Oral therapy (preferred):
     • Amoxicillin/clavulanic acid or
     • Cefalexin with metronidazole 2
   • IV therapy (if unable to tolerate oral intake):
     • Cefuroxime or ceftriaxone plus metronidazole
     • Ampicillin/sulbactam 2
   • Duration: 5-7 days if good clinical response 1

Complicated Diverticulitis

1. Intravenous antibiotics:

   • Single-agent options:
     • Piperacillin-tazobactam
     • Ertapenem
     • Meropenem or imipenem/cilastatin (severe cases) 1
   • Combination therapy options:
     • Ceftriaxone + metronidazole
     • Ciprofloxacin + metronidazole
     • Ampicillin + gentamicin + metronidazole 1
   • Initial IV therapy for 3-5 days, then transition to oral therapy 1

2. Interventional management:

   • Percutaneous drainage for localized abscesses 1
   • Surgical intervention for perforated diverticulitis with diffuse peritonitis:
     • Stable patients: Primary resection and anastomosis (with/without diverting stoma)
     • Unstable/high-risk patients: Hartmann's procedure
     • Severe hemodynamic instability: Damage control procedure 1

Monitoring and Follow-up

• Reassess within 48-72 hours
• Transition to oral therapy when:
  • Clinically improving
  • Afebrile for 24 hours
  • Able to tolerate oral intake 1
• Expect pain resolution within 2-3 days of appropriate management
• Consider colonoscopy 4-6 weeks after resolution of complicated diverticulitis to rule out malignancy 1

Prevention of Recurrence

• High-fiber diet (fruits, vegetables, whole grains, legumes)
• Regular physical activity
• Smoking cessation
• Avoid NSAIDs, opiates, and corticosteroids 1
• Fiber supplementation and poorly absorbed antibiotics like rifaximin may benefit patients with symptomatic uncomplicated diverticular disease 1, 4

Important Caveats

1. Outpatient management is safe and effective for uncomplicated diverticulitis with success rates over 92% 5
2. Antibiotic overuse: Recent evidence shows antibiotics neither accelerate recovery nor prevent complications or recurrence in uncomplicated cases 3
3. Surgical consultation should be considered for:
   • Immunocompromised patients with history of diverticulitis
   • Recurrent symptomatic episodes
   • Complications (strictures, fistulae) 1
4. Elective colectomy is not advised for immunocompetent patients with uncomplicated diverticulosis or recurrent uncomplicated diverticulitis 1
5. Mortality rates differ significantly between elective (0.5%) and emergent (10.6%) colon resection 2