Criteria for Supportive Care Without Antibiotics in Diverticulitis
For immunocompetent patients with uncomplicated diverticulitis and no high-risk features, observation with supportive care alone (no antibiotics) is the recommended first-line approach. 1
Definition of Uncomplicated Diverticulitis
Uncomplicated diverticulitis is defined as localized diverticular inflammation without any of the following complications 1:
- Abscess formation
- Perforation with free air
- Fistula
- Obstruction
- Bleeding
This diagnosis should be confirmed by CT scan with contrast, which has 98-99% sensitivity and 99-100% specificity. 1
Patient Selection Criteria for Supportive Care Only
Patients must meet ALL of the following criteria to qualify for observation without antibiotics 1, 2, 3:
Clinical Status Requirements
- Able to tolerate oral fluids and medications 1
- Temperature <100.4°F (38°C) 1
- Pain score <4/10 on visual analogue scale, controlled with acetaminophen alone 1
- No persistent vomiting 1
- Able to maintain adequate hydration 1
Patient Characteristics
- Immunocompetent status (not on chemotherapy, high-dose steroids, or immunosuppression for organ transplant) 1
- Age ≤80 years 1
- Not pregnant 1
- No significant comorbidities or frailty (no cirrhosis, chronic kidney disease, heart failure, or poorly controlled diabetes) 1
- Adequate home and social support 1, 3
Laboratory and Imaging Criteria
- White blood cell count ≤15 × 10⁹ cells/L 1
- C-reactive protein ≤140 mg/L 1
- No fluid collection or abscess on CT 1
- No pericolic extraluminal air 1
- Shorter segment of inflammation (not extensive) 1
Clinical Course Indicators
- Symptoms present for ≤5 days prior to presentation 1
- ASA score I or II (not III or IV) 1
- No signs of systemic inflammatory response or sepsis 1
Evidence Supporting This Approach
Multiple high-quality randomized controlled trials, including the landmark DIABOLO trial with 528 patients, demonstrate that antibiotics neither accelerate recovery nor prevent complications or recurrence in uncomplicated cases. 1 At 24-month follow-up, there were no differences in recurrent diverticulitis rates, complicated diverticulitis, or need for sigmoid resection between antibiotic and non-antibiotic groups. 1 Hospital stays are actually shorter in observation groups (2 vs 3 days). 1
Research studies confirm that outpatient treatment without antibiotics is viable in approximately 95% of selected patients with uncomplicated diverticulitis, with treatment failure rates of only 5-10%. 4, 2, 5
Supportive Care Protocol
When antibiotics are not indicated, provide the following 1:
- Clear liquid diet during acute phase, advancing as symptoms improve 1
- Acetaminophen for pain control (avoid NSAIDs and opioids) 1
- Bowel rest initially 1
- Adequate oral hydration 1
Mandatory Follow-Up
Re-evaluation within 7 days is mandatory, with earlier assessment (within 48-72 hours) if clinical condition deteriorates. 1, 6 Patients should return immediately for fever >101°F, severe uncontrolled pain, persistent nausea/vomiting, inability to eat or drink, or signs of dehydration. 1
Common Pitfalls to Avoid
Do not apply the "no antibiotics" approach to patients with any of the following 1:
- Hinchey 1b or higher disease (abscess present, even if small) 1
- Any of the high-risk features listed above 1
- Immunocompromised status of any kind 1
- Signs of systemic infection or sepsis 1
The evidence supporting observation without antibiotics specifically excluded patients with abscesses and higher Hinchey stages—applying this approach to complicated disease is inappropriate and potentially dangerous. 1
Overusing antibiotics in truly uncomplicated cases without risk factors contributes to antibiotic resistance without providing clinical benefit. 1 However, failing to recognize high-risk features that predict progression to complicated disease can lead to serious complications. 1