Treatment of Diverticulitis
The treatment of diverticulitis should be tailored based on disease severity, with antibiotics used selectively rather than routinely in immunocompetent patients with mild uncomplicated diverticulitis, while antibiotics are mandatory for complicated cases or high-risk patients. 1, 2
Classification of Diverticulitis
- Uncomplicated diverticulitis: Localized diverticular inflammation without abscess or perforation, typically confirmed by CT scan showing diverticula, wall thickening, and increased density of pericolic fat 2
- Complicated diverticulitis: Involves abscess formation, perforation, fistula, or obstruction 2
Treatment of Uncomplicated Diverticulitis
Diet and Supportive Care
- A clear liquid diet is advised during the acute phase of uncomplicated diverticulitis 1
- Diet should be advanced as symptoms improve, typically within 3-5 days 1
- Pain management with acetaminophen is appropriate for most patients 3
Antibiotic Therapy
- Antibiotics can be used selectively, rather than routinely, in immunocompetent patients with mild uncomplicated diverticulitis 1
- Multiple high-quality studies have shown no difference in time to resolution, risk of readmission, progression to complications, or need for surgery between patients treated with or without antibiotics for uncomplicated diverticulitis 1, 4
Indications for Antibiotics in Uncomplicated Diverticulitis
Antibiotics are indicated for uncomplicated diverticulitis in patients with:
- Comorbidities or frailty 1
- Refractory symptoms or vomiting 1
- CRP >140 mg/L or WBC >15 × 10^9/L 1, 2
- Fluid collection or longer segment of inflammation on CT scan 1
- Immunocompromised status (receiving chemotherapy, high-dose steroids, post-transplant) 1, 3
- Advanced age (>80 years) 2, 3
- Systemic symptoms such as persistent fever or chills 2, 3
- Pregnancy 3
- Chronic medical conditions (cirrhosis, chronic kidney disease, heart failure, poorly controlled diabetes) 3
Antibiotic Selection When Indicated
- Outpatient treatment: Oral fluoroquinolone (e.g., ciprofloxacin) plus metronidazole, or amoxicillin-clavulanate monotherapy for 4-7 days 1, 5
- Inpatient treatment: IV antibiotics with gram-negative and anaerobic coverage (e.g., ceftriaxone plus metronidazole, ampicillin/sulbactam, or piperacillin-tazobactam) 3, 6
- Duration: 4-7 days for immunocompetent patients; 10-14 days for immunocompromised patients 1, 2
Treatment of Complicated Diverticulitis
- For small abscesses (<4-5 cm): Antibiotic therapy alone for 7 days 2
- For large abscesses (>4-5 cm): Percutaneous drainage combined with antibiotic therapy 2
- Surgical intervention if clinical deterioration occurs or for complications like perforation with generalized peritonitis 2, 3
- Intravenous antibiotics such as ceftriaxone plus metronidazole or piperacillin-tazobactam 3
Outpatient vs. Inpatient Management
Outpatient Management Criteria
- Uncomplicated diverticulitis 2, 5
- Ability to tolerate oral intake 2
- Adequate pain control 2
- Absence of significant comorbidities 2
- Reliable patient with good follow-up 5
Inpatient Management Criteria
- Complicated diverticulitis 2
- Significant comorbidities 2
- Inability to tolerate oral intake 2
- Severe pain or systemic symptoms 2
- Immunocompromised status 1
Special Considerations
Immunocompromised Patients
- Higher risk for severe or complicated disease 1
- Low threshold for cross-sectional imaging, antibiotic treatment, and surgical consultation 1
- Longer duration of antibiotic treatment (10-14 days) 1
- Consider consultation with a colorectal surgeon after recovery to discuss elective resection 1
Common Pitfalls to Avoid
- Unnecessary use of antibiotics in low-risk patients with uncomplicated diverticulitis provides no benefit and contributes to antibiotic resistance 2, 4
- Failure to recognize high-risk patients who need antibiotics despite having uncomplicated disease can lead to progression to complicated diverticulitis 2, 4
- Inadequate follow-up to ensure resolution of symptoms can lead to delayed diagnosis of complications 4
- Missing signs of progression to complicated diverticulitis can lead to delayed treatment 4