What is the initial treatment for acute diverticulitis?

From the Guidelines

The initial treatment for acute diverticulitis should prioritize outpatient management without antibiotics for select patients with uncomplicated left-sided colonic diverticulitis, as suggested by the American College of Physicians (ACP) guideline 1. This approach is based on low-certainty evidence that shows no differences in diverticulitis-related complications, quality of life, need for surgery, or long-term recurrence between patients receiving and those not receiving antibiotics.

• The ACP guideline recommends that clinicians manage most patients with acute uncomplicated left-sided colonic diverticulitis in an outpatient setting, with a conditional recommendation based on low-certainty evidence 1.
• The guideline also suggests that clinicians initially manage select patients with acute uncomplicated left-sided colonic diverticulitis without antibiotics, with a conditional recommendation based on low-certainty evidence 1.
• A study published in the World Journal of Emergency Surgery in 2020 found that antibiotics can be safely omitted in patients with a first episode of uncomplicated acute left-sided colonic diverticulitis (Hinchey 1a) 1.
• Another study published in the same journal in 2022 suggested that antibiotic therapy can be avoided in immunocompetent elderly patients with uncomplicated left colonic diverticulitis without sepsis-related organ failures, with a conditional recommendation based on very low-quality evidence 1. However, it is essential to note that these recommendations do not apply to patients with complicated diverticulitis, systemic inflammatory response, immunosuppression, or ongoing or recent antibiotic treatment.
• Patients with symptoms lasting longer than 5 days, vomiting, systemic comorbidity, high C-reactive protein levels, or CT findings of pericolic extraluminal air, fluid collection, or a longer inflamed colon segment are at higher risk of progression to complicated disease and may require antibiotic treatment 1.
• The decision to use antibiotics should be based on individual patient circumstances, such as the availability of adequate home care, and should take into account the potential harms of antibiotic treatment, including increased costs, adverse events, and the risk of antimicrobial resistance 1.

From the Research

Initial Treatment for Acute Diverticulitis

The initial treatment for acute diverticulitis typically involves a combination of medical therapies aimed at resolving the infection and inflammation.

• The treatment often includes a liquid diet to rest the bowel and reduce symptoms.
• Antibiotics are commonly prescribed to treat the infection, with the choice of antibiotic depending on the severity of the disease and the presence of any complications 2, 3, 4.
• For uncomplicated cases, outpatient treatment with oral antibiotics has been shown to be safe and effective, with success rates of over 92% in some studies 2, 5, 6.
• The specific antibiotics used may include metronidazole, ciprofloxacin, and amoxicillin-clavulanic acid, among others 3, 4, 6.
• In more severe cases or when complications are present, hospitalization and intravenous antibiotics may be necessary 3, 5.

Outpatient Treatment

Outpatient treatment for uncomplicated acute diverticulitis has been demonstrated to be a viable option, with several studies showing its safety and efficacy.

• A study published in 2016 found that outpatient treatment with oral antibiotics was successful in over 92% of cases, with only 8% of patients requiring admission to the hospital 2.
• Another study from 2012 compared outpatient treatment with intravenous antibiotics and found no significant differences in complications or relapse rates between the two groups 5.
• Outpatient treatment has also been shown to be cost-effective, with one study estimating a savings of approximately 1,600 € per patient compared to inpatient treatment 5.

Antibiotic Selection

The selection of antibiotics for the treatment of acute diverticulitis is typically based on the severity of the disease and the presence of any complications.

• For uncomplicated cases, oral antibiotics such as metronidazole and ciprofloxacin are commonly used 2, 6.
• In more severe cases or when complications are present, intravenous antibiotics such as ampicillin, gentamicin, and piperacillin-tazobactam may be necessary 3, 4.
• The duration of antibiotic therapy is typically 7-10 days, although the optimal duration is not well established and may vary depending on the individual case 3.