Treatment of Diverticulitis
Most immunocompetent patients with uncomplicated diverticulitis do NOT require antibiotics and should be managed with observation, clear liquid diet, and acetaminophen for pain control. 1
Initial Diagnostic Confirmation
- CT scan with IV contrast is the gold standard for diagnosing diverticulitis, with 98-99% sensitivity and 99-100% specificity 1, 2
- Uncomplicated diverticulitis is defined as localized inflammation without abscess, perforation, fistula, obstruction, or bleeding 1, 2
- Approximately 85-88% of acute diverticulitis cases are uncomplicated 1, 2
- Laboratory workup should include complete blood count, basic metabolic panel, and C-reactive protein 2, 3
Treatment Algorithm for Uncomplicated Diverticulitis
Step 1: Determine if Antibiotics Are Needed
Reserve antibiotics ONLY for patients with specific high-risk features: 1
- Immunocompromised status (chemotherapy, high-dose steroids, organ transplant) 1, 2
- Age >80 years 1, 2
- Pregnancy 1, 2
- Persistent fever or chills despite supportive care 1
- Increasing leukocytosis 1
- CRP >140 mg/L 1
- White blood cell count >15 × 10^9 cells/L 1
- Vomiting or inability to maintain oral hydration 1
- Significant comorbidities (cirrhosis, chronic kidney disease, heart failure, poorly controlled diabetes) 1, 2
- CT findings of fluid collection, longer segment of inflammation, or pericolic extraluminal air 1
- ASA score III or IV 1
- Symptoms lasting >5 days prior to presentation 1
This recommendation is based on multiple high-quality randomized trials, including the DIABOLO trial with 528 patients, demonstrating that antibiotics neither accelerate recovery nor prevent complications or recurrence in uncomplicated cases. 1
Step 2: Outpatient vs. Inpatient Management
Outpatient management is appropriate when patients meet ALL of the following criteria: 1
- Able to tolerate oral fluids and medications 1
- Temperature <100.4°F 1
- Pain score <4/10 (controlled with acetaminophen only) 1
- No significant comorbidities or frailty 1
- Adequate home and social support 1
- Ability to maintain self-care at pre-illness level 1
Hospitalization is required for: 1
- Complicated diverticulitis 1
- Inability to tolerate oral intake 1
- Systemic inflammatory response or sepsis 1
- Significant comorbidities or frailty 1
- Immunocompromised status 1
Step 3: Antibiotic Regimens (When Indicated)
Outpatient Oral Regimens (4-7 days for immunocompetent patients): 1
- First-line: Ciprofloxacin 500 mg orally twice daily PLUS metronidazole 500 mg orally three times daily 1, 2
- Alternative: Amoxicillin-clavulanate 875/125 mg orally twice daily 1, 2
Inpatient IV Regimens: 1
- Ceftriaxone PLUS metronidazole 1, 2
- Piperacillin-tazobactam 1, 2
- Transition to oral antibiotics as soon as patient tolerates oral intake 1
Duration of Therapy: 1
Step 4: Supportive Care for All Patients
- Clear liquid diet during acute phase, advancing as symptoms improve 1
- Acetaminophen for pain control (avoid NSAIDs and opioids) 1
- Adequate hydration 1
Treatment of Complicated Diverticulitis
Small abscesses (<4-5 cm): 1
- IV antibiotics alone for 7 days with gram-negative and anaerobic coverage 1
Large abscesses (≥4-5 cm): 1
- Percutaneous CT-guided drainage PLUS IV antibiotics 1
- Continue antibiotics for 4 days after adequate source control in immunocompetent patients 1
- Up to 7 days for immunocompromised or critically ill patients 1
Generalized peritonitis or sepsis: 1
- Emergent surgical consultation 1
- IV antibiotics (ceftriaxone plus metronidazole or piperacillin-tazobactam) 1, 2
- Source control surgery (Hartmann's procedure or primary resection with anastomosis) 1
Mandatory Follow-Up and Monitoring
- Re-evaluation within 7 days from diagnosis, or sooner if clinical condition deteriorates 1
- Colonoscopy 6-8 weeks after symptom resolution for: 1
Prevention of Recurrence
Dietary and Lifestyle Modifications: 1
- High-quality diet rich in fiber (>22.1 g/day) from fruits, vegetables, whole grains, and legumes 1
- Regular vigorous physical activity 1
- Achieve or maintain normal BMI (18-25 kg/m²) 1
- Smoking cessation 1
- Avoid regular use of NSAIDs and opioids when possible 1
Do NOT restrict nuts, seeds, or popcorn—this is not evidence-based and may reduce overall fiber intake. 1
Do NOT prescribe mesalamine, rifaximin, or probiotics for prevention—these have no proven benefit. 1
Surgical Considerations for Recurrent Diverticulitis
Elective sigmoidectomy should be individualized based on: 1
- Quality of life impact 1
- Frequency of recurrence (≥3 episodes within 2 years) 1
- Duration of persistent symptoms (>3 months) 1
- Patient preferences 1
The DIRECT trial demonstrated significantly better quality of life at 6 months and 5-year follow-up with elective surgery compared to continued conservative management in patients with recurrent/persistent symptoms. 1
The traditional "two-episode rule" for elective surgery is no longer accepted. 1
Critical Pitfalls to Avoid
- Do NOT routinely prescribe antibiotics for uncomplicated diverticulitis in immunocompetent patients without risk factors 1
- Do NOT assume all patients require hospitalization—outpatient management results in 35-83% cost savings 1
- Do NOT unnecessarily restrict nuts, seeds, and popcorn 1
- Do NOT apply the "no antibiotics" approach to complicated diverticulitis or immunocompromised patients 1
- Do NOT stop antibiotics early if they are indicated, even if symptoms improve 1
- Do NOT delay surgical consultation in patients with frequent recurrences affecting quality of life 1
Special Population Considerations
Immunocompromised patients: 1
- Lower threshold for CT imaging, antibiotic treatment, and surgical consultation 1
- Longer antibiotic duration (10-14 days) required 1
- May present with milder signs despite more severe disease 1
- Corticosteroid use specifically increases risk of perforation and death 1
Elderly patients (>65 years): 1