From the Guidelines
Antibiotics should be used in patients with diverticulitis who have comorbidities, are frail, present with refractory symptoms or vomiting, or have a CRP >140 mg/L or baseline white blood cell count > 15 × 10^9 cells per liter, as well as in patients with complicated diverticulitis or uncomplicated diverticulitis with a fluid collection or longer segment of inflammation on CT scan. The use of antibiotics in diverticulitis is a topic of ongoing debate, with recent evidence suggesting that they may not be necessary for all patients with uncomplicated diverticulitis 1. However, certain patient populations, such as those with comorbidities or who are frail, may benefit from antibiotic treatment.
Patient Selection for Antibiotic Treatment
When selecting patients for antibiotic treatment, clinicians should consider the following factors:
- Presence of comorbidities or frailty
- Refractory symptoms or vomiting
- Elevated CRP (>140 mg/L) or white blood cell count (> 15 × 10^9 cells per liter)
- Complicated diverticulitis or uncomplicated diverticulitis with a fluid collection or longer segment of inflammation on CT scan
Antibiotic Regimens
For patients who require antibiotic treatment, the following regimens may be considered:
- Metronidazole (500 mg three times daily) plus either ciprofloxacin (500 mg twice daily) or trimethoprim-sulfamethoxazole (160/800 mg twice daily) for 7-10 days
- Amoxicillin-clavulanate (875/125 mg twice daily) as monotherapy
- Intravenous antibiotics such as ceftriaxone (1-2 g daily) plus metronidazole (500 mg every 8 hours), or piperacillin-tazobactam (3.375 g every 6 hours) for hospitalized patients with severe or complicated diverticulitis
Rationale for Antibiotic Use
The use of antibiotics in diverticulitis is intended to reduce the risk of complications, such as abscess formation or perforation, and to improve patient outcomes 1. However, the decision to use antibiotics should be made on a case-by-case basis, taking into account the individual patient's risk factors and clinical presentation.
From the Research
Treatment of Diverticulitis with Antibiotics
- The use of antibiotics in treating diverticulitis depends on the severity and classification of the disease 2, 3.
- For uncomplicated diverticulitis, antibiotics have no proven benefit in reducing the duration of the disease or preventing recurrence, and should only be used selectively 2.
- However, some studies suggest that antibiotics may be effective in obtaining symptom relief and improving symptoms in patients with uncomplicated diverticulitis 3.
- In patients with complicated diverticulitis, non-operative management, including bowel rest and intravenous antibiotics, is indicated for small abscesses 2.
- For patients with peritonitis and sepsis, rapid antibiotic administration and urgent surgery are recommended 2.
- The choice of antibiotic regimen may not significantly impact outcomes, with ceftriaxone and metronidazole showing non-inferior outcomes to piperacillin/tazobactam for treating complicated diverticulitis 4.
Outpatient Treatment with Antibiotics
- Outpatient treatment with oral antibiotics may be safe and effective for patients with uncomplicated acute diverticulitis who are able to tolerate oral intake and have adequate family support 5.
- A study found that ambulatory treatment was completed without complication in 97% of patients with uncomplicated acute diverticulitis 5.
- However, the evidence supporting outpatient treatment with oral antibiotics is limited, and more research is needed to determine the optimal treatment approach 6.
Classification and Diagnosis
- Radiological evidence of inflammation, using computed tomography (CT), is needed to diagnose the first occurrence of diverticulitis and to classify the disease as complicated or uncomplicated 2.
- CT scans can help identify patients who require more aggressive treatment, such as those with perforation or abscesses 2.
- The classification of diverticulitis as complicated or uncomplicated is used to direct management and guide treatment decisions 2.