Clinical impacts of utilizing ceftriaxone and metronidazole versus piperacillin/tazobactam in patients diagnosed with complicated diverticulitis.

Background: The optimal antibiotic regimen to empirically treat complicated diverticulitis has not been well established in guidelines.

Methods: A 5-year retrospective cohort study was conducted with 322 patients admitted to Mayo Clinic hospitals for complicated diverticulitis. Outcomes for 89 patients treated with ceftriaxone and metronidazole were compared to 233 patients treated with piperacillin/tazobactam. Patients were included if they received one of the treatment options for at least 96 ​h during hospital admission and did not receive any other diverticulitis antibiotic treatment regimen for at least 96 ​h.

Results: Ceftriaxone and metronidazole was found to be non-inferior to piperacillin/tazobactam for the combined primary outcome of 30-day readmission or all-cause mortality (21.4 ​% vs 15.9 ​%, P ​= ​0.12). No significant differences were found for 30-day antibiotic failure (P ​= ​0.30) or 90-day Clostridioides difficile infection rate (P ​= ​0.96). Patients who received oral antibiotic therapy in the 7 days prior to admission were found to have increased risk of mortality or readmission and antibiotic failure.

Conclusions: Ceftriaxone and metronidazole showed non-inferior outcomes to piperacillin/tazobactam for treating complicated diverticulitis.