Which antibiotics for mild left-sided diverticulitis?

Atualizado: 14 de abr. de 2023

Acute diverticulitis is a common entity surgeons must deal with. Although the severe and complicated disease is a possibility, some patients resort to the emergency department with uncomplicated diverticulitis. Depending on patients’ complaints, treatment can range from discharge home to hospital admission for intravenous antibiotics administration.

For left-sided acute uncomplicated diverticulitis (AUD) observational management seems to be safe, but strong data was lacking. So, antibiotics for left-sided AUD have been common practice for the last decades. Additionally, doctors feel safer by prescribing antibiotics for all grades of diverticulitis. Is this approach necessary? Is observational management safe for left-sided AUD?

Yunli Zhao et al. from China, Canada, and the USA, presented 2023 a meta-analysis of four RCTs evaluating the safety and effectiveness of antibiotics for mild left-sided AUD. They included 1809 patients with mild left-sided AUD (42.13% male vs. 64.59% female). Three studies included only inpatients, and one study only outpatients. The follow-up was one to twelve months. Antibiotics were given for 7 days in three studies and 10 days in one study. Antibiotics regimens were as follows:

Intravenous second- or third-generation cephalosporin plus metronidazole, or carbapenem, or piperacillin/tazobactam; switching to oral ciprofloxacin or cefadroxil plus metronidazole at discharge.
Intravenous amoxicillin/clavulanic acid for at least 48h, then switching to oral.
Oral amoxicillin/clavulanic acid.
Intravenous cefuroxime plus oral metronidazole for 48h, and then oral administration.

According to the authors, the results found in this meta-analysis support the idea of no antibiotics for left-sided AUD. Why? Compared to no antibiotics, antibiotics administration showed little or no impact on sigmoid resection, recurrent diverticulitis, duration of stay, and on mortality. The impact on readmission was probably little or none. Although with a low level of certainty, antibiotics administration in mild left-sided AUD probably decreases the risk of ongoing diverticulitis (data from just one study). The most common adverse effect of antibiotics was diarrhea. Yunli Zhao et al state that for mild left-sided AUD outpatient treatment is safe since no patient needed emergency surgery during follow-up.

According to the results published in BJS 2023 by this group of authors from China, Canada, and the USA, there is little evidence of the benefits of antibiotics administration (intravenous or oral) for the treatment of mild left-sided AUD. In my opinion, these results are important for clinical practice and to decrease the use of unnecessary antibiotics. Even so, I would advise close surveillance to avoid serious complications. As for inpatient or outpatient treatment, doctors must consider the patients’ complaints, patients’ capability of easily resorting to an emergency department if needed, and patients’ family support. Additionally, doctors must evaluate the patient-doctor relationship to understand the level of confidence the patient and family have in the outpatient treatment option.