What is the appropriate management for a patient diagnosed with diverticulitis?

Management of Diverticulitis

For patients with acute diverticulitis, management should be based on disease severity, with uncomplicated cases managed in outpatient settings without antibiotics in select patients, while complicated cases require antibiotics and possible surgical intervention. 1, 2

Classification and Diagnosis

• Diagnosis: CT imaging with IV contrast is recommended when there is diagnostic uncertainty (98% sensitivity, 99% specificity) 1, 2
• Classification:
  • Uncomplicated diverticulitis: Localized inflammation without abscess, perforation, fistula, or obstruction (85% of cases) 3
  • Complicated diverticulitis: Presence of abscess, phlegmon, fistula, obstruction, bleeding, or perforation (approximately 12% of cases) 1

Management of Uncomplicated Diverticulitis

Outpatient Management

• The American College of Physicians suggests managing most patients with acute uncomplicated left-sided colonic diverticulitis in an outpatient setting 1
• Suitable candidates for outpatient management:
  • Hemodynamically stable
  • No significant comorbidities
  • Able to tolerate oral intake
  • Adequate pain control
  • Good social support
  • Reliable follow-up

Antibiotic-Free Approach

• The ACP suggests initially managing select patients with acute uncomplicated diverticulitis without antibiotics 1, 2
• Appropriate candidates for observation without antibiotics:
  • Immunocompetent patients
  • No systemic inflammatory response
  • Not medically frail
  • No significant comorbidities

Supportive Care

• Pain management: Acetaminophen preferred over NSAIDs 2
• Diet: Initially clear liquid diet, advancing as tolerated 2
• Close monitoring with watchful waiting 2

Indications for Antibiotics in Uncomplicated Diverticulitis

• Systemic symptoms (persistent fever, chills)
• Increasing leukocytosis
• Immunocompromised status
• Age >80 years
• Pregnancy
• Significant comorbidities (cirrhosis, chronic kidney disease, heart failure, poorly controlled diabetes)
• Symptoms lasting >5 days
• Initial pain score >7
• Vomiting 2, 3

Antibiotic Regimens (if indicated)

• Oral: Amoxicillin/clavulanic acid or cefalexin with metronidazole
• IV (if unable to tolerate oral intake): Ceftriaxone plus metronidazole, piperacillin-tazobactam, or ampicillin/sulbactam 2, 3

Management of Complicated Diverticulitis

Abscess Management

• Small abscesses (<4-5 cm): Antibiotic therapy alone
• Large abscesses (≥4-5 cm): Percutaneous drainage plus antibiotics 2

Peritonitis Management

• Immediate surgical intervention with antibiotic therapy
• Fluid resuscitation and prompt antibiotic administration 1, 2

Surgical Options

• For peritonitis or failure of non-operative management:
  • Hartmann procedure (resection with end colostomy)
  • Primary anastomosis with or without diverting loop ileostomy 1, 4
• For distant free gas without diffuse intra-abdominal fluid:
  • Selected stable patients may be managed non-operatively with close follow-up 1

Prevention of Recurrence

• High-fiber diet or fiber supplementation (AGA conditional recommendation) 1
• Regular physical activity 1, 2
• The AGA suggests against routinely advising patients to avoid consumption of nuts and popcorn 1
• The AGA suggests advising patients to avoid non-aspirin NSAIDs if possible 1
• The AGA recommends against the use of mesalamine after acute uncomplicated diverticulitis 1
• The AGA suggests against the use of rifaximin or probiotics after acute uncomplicated diverticulitis 1

Follow-up

• Colonoscopy is recommended 4-6 weeks after resolution of complicated diverticulitis to rule out malignancy 2, 4
• Monitor for treatment failure (persistent symptoms or worsening clinical condition) 2

Special Considerations

• Elderly patients (>65 years): Higher risk of complications, lower threshold for CT imaging and antibiotic therapy due to atypical presentation 2
• Immunocompromised patients: More aggressive management with antibiotics and lower threshold for hospitalization 2, 3

Pitfalls and Caveats

• Failure to recognize complicated diverticulitis can lead to increased morbidity and mortality
• Overuse of antibiotics in uncomplicated cases contributes to antimicrobial resistance
• Patients with distant intraperitoneal gas have a high failure rate (57-60%) with non-operative management 1
• Postoperative mortality is significantly higher for emergency surgery (10.6%) compared to elective surgery (0.5%) 3