What is the appropriate treatment for a patient with diverticulitis?

Management of Diverticulitis

For patients with diverticulitis confirmed on CT scan, hospitalization with IV antibiotics, pain management, and clear liquid diet is indicated for complicated diverticulitis or uncomplicated diverticulitis with risk factors, while selective antibiotic use is appropriate for mild uncomplicated cases. 1

Classification and Initial Assessment

Diverticulitis is classified based on CT findings into:

• Uncomplicated diverticulitis: Colonic wall thickening and peri-colonic inflammation without abscess, perforation, fistula, or obstruction
• Complicated diverticulitis: Presence of abscess, peritonitis, obstruction, stricture, or fistula formation

Treatment Approach

Uncomplicated Diverticulitis

1. Antibiotic Selection:

   • Selective antibiotic use is recommended rather than routine use in immunocompetent patients with mild uncomplicated diverticulitis 2
   • Antibiotics are indicated if the patient has:
     • Comorbidities or frailty
     • Refractory symptoms or vomiting
     • CRP >140 mg/L or WBC >15 × 10^9 cells/L
     • Fluid collection or longer segment of inflammation on CT
     • Immunocompromise (receiving chemotherapy, high-dose steroids, organ transplant)
     • Age >80 years
     • Pregnancy
     • Chronic medical conditions (cirrhosis, CKD, heart failure, poorly controlled diabetes) 1, 3

2. Antibiotic Regimens:

   • Oral regimens (for patients who can tolerate oral intake):

     • Amoxicillin-clavulanate OR
     • Cefalexin with metronidazole OR
     • Ciprofloxacin with metronidazole 1, 3

   • IV regimens (for patients unable to tolerate oral intake):

     • Ceftriaxone plus metronidazole OR
     • Piperacillin-tazobactam OR
     • Ampicillin/sulbactam 1, 3

3. Diet:

   • Clear liquid diet during acute phase
   • Advance diet as symptoms improve 2

4. Pain Management:

   • Acetaminophen is typically recommended 3

Complicated Diverticulitis

1. Antibiotics: IV broad-spectrum antibiotics are mandatory

   • Ceftriaxone plus metronidazole OR
   • Piperacillin-tazobactam 1, 3

2. Abscess Management:

   • Small abscesses (<4-5 cm): Antibiotic therapy alone
   • Large abscesses (≥4-5 cm): Percutaneous drainage plus antibiotics 1

3. Surgical Intervention:

   • Immediate surgical intervention for peritonitis or hemodynamic instability
   • Fluid resuscitation and prompt antibiotic administration 1

Duration of Treatment

• Typical antibiotic duration: 7-10 days, individualized based on clinical response 1
• Hospitalization duration depends on clinical improvement and resolution of symptoms

Common Pitfalls and Caveats

1. Relying solely on clinical diagnosis without imaging:

   • Clinical suspicion alone is correct in only 40-65% of patients
   • CT scan with oral and IV contrast is the gold standard (95-99% sensitivity/specificity) 1

2. Overuse of antibiotics in mild uncomplicated cases:

   • Recent evidence shows no benefit in immunocompetent patients with mild uncomplicated diverticulitis 2

3. Delayed surgical consultation:

   • Immediate surgical consultation is essential in cases of peritonitis or hemodynamic instability 1

4. Inadequate follow-up:

   • Colonoscopy should be performed 4-6 weeks after resolution of complicated diverticulitis to rule out malignancy 1
   • Monitor for treatment failure (persistent symptoms or worsening clinical condition)

5. Overlooking ongoing inflammation:

   • Approximately 5% of patients experience persistent abdominal pain with continued evidence of inflammation on CT scan 1
   • Consider visceral hypersensitivity if no evidence of ongoing inflammation is found 2

Prevention of Recurrence

• High-fiber diet focusing on fruits, vegetables, whole grains, and legumes
• Regular physical activity
• Smoking cessation
• Avoidance of NSAIDs, opiates, and corticosteroids
• Weight management 1