What are the recommended antibiotics for diverticulitis with perforation?

Antibiotic Therapy for Diverticulitis with Perforation

For diverticulitis with perforation, broad-spectrum antibiotics covering gram-positive, gram-negative, and anaerobic bacteria are mandatory, with a recommended duration of 4 days after adequate source control. 1

Recommended Antibiotic Regimens

• Antibiotic selection should be based on the severity of infection, presumed pathogens, and risk factors for resistance patterns 1
• For perforated diverticulitis with diffuse peritonitis, empiric coverage must include:
  • Gram-positive bacteria coverage
  • Gram-negative bacteria coverage
  • Anaerobic bacteria coverage 1, 2

Specific Regimen Options

• Inpatient IV options:

  • Piperacillin-tazobactam 3
  • Ceftriaxone plus metronidazole 3
  • Ertapenem (1g IV daily) - particularly effective for complicated intra-abdominal infections 4
  • Ampicillin-sulbactam 3

• Special considerations:

  • Anti-ESBL producer coverage should be included for patients with:
    • Prior antibiotic exposure
    • Comorbidities requiring concurrent antibiotic therapy 1, 2
  • Immunocompromised patients require broader coverage and longer treatment duration (10-14 days) 1

Duration of Therapy

• 4 days of antibiotic therapy is recommended after adequate source control 1, 2
• The STOP IT trial demonstrated that outcomes after 4 days of antibiotics were similar to longer courses extending until resolution of physiological abnormalities 1
• Patients with ongoing signs of peritonitis or systemic illness beyond 5-7 days warrant further diagnostic investigation 1

Management Algorithm

1. Initial assessment:

   • Evaluate for signs of sepsis or peritonitis (requires urgent surgical intervention) 1
   • Obtain CT scan to confirm perforation and assess extent 5

2. Source control:

   • Small abscesses: non-operative management with antibiotics 6
   • Larger abscesses (3-5 cm): percutaneous drainage plus antibiotics 6
   • Generalized peritonitis: surgical intervention with either Hartmann procedure or primary anastomosis 1, 6

3. Antibiotic therapy:

   • Start broad-spectrum antibiotics immediately upon diagnosis 1
   • Obtain intraperitoneal samples for microbiological evaluation 1
   • De-escalate antibiotics based on culture results when available 1
   • Continue for 4 days after adequate source control 1, 2

Special Patient Populations

• Elderly patients:

  • Empiric antibiotic regimen should account for higher likelihood of resistant organisms 1
  • Consider physiological age and comorbidities when selecting antibiotics 1

• Immunocompromised patients:

  • Higher risk for complications and treatment failure 1
  • Require longer antibiotic duration (10-14 days) 1
  • Early surgical consultation is recommended 1

Important Caveats

• Local epidemiological data and resistance profiles should guide antibiotic selection 1
• Right-sided colonic diverticulitis should be treated with the same antibiotic principles as left-sided diverticulitis 1, 2, 7
• Ineffective or inadequate antimicrobial treatment is significantly linked to poor outcomes in critically ill patients 1
• In patients with organ dysfunction and septic shock, broad empiric antimicrobial therapy should be started as soon as possible 1