Effectiveness of Treatment with Antibiotics Alone in Patients with Acute Diverticulitis and Pelvic Abscesses.

Introduction: The available evidence regarding the treatment of acute diverticulitis (AD) with pelvic abscess using antibiotics alone is very limited. The objective of this study was to determine whether the short- and long-term outcomes of AD with pelvic abscesses treated exclusively with antibiotics are comparable to those of pericolic abscesses. Methods: A retrospective study was conducted on patients diagnosed with AD and either pelvic or pericolic abscesses, as confirmed by computed tomography, who were treated solely with antibiotic therapy between 2011 and 2021. Cases involving percutaneous drainage as part of conservative treatment were excluded. Results: Fifty-eight patients met the inclusion criteria, comprising 12 with pelvic abscesses and 46 with pericolic abscesses. Both groups exhibited similar baseline characteristics and radiological findings, except for a more frequent presence of free fluid in pelvic abscesses. The success rate of antibiotic therapy was 91.7% for pelvic abscess cases and 96.7% for pericolic cases (p = 0.508). No significant differences were observed in recurrence or elective surgery. In the subgroup of abscesses with a diameter ≥4 cm, the evolution was similar in both locations (treatment success rate of 87.5% in pelvic and 94.4% in pericolic; p = 0.529), although recurrence was slightly higher for pericolic abscesses (38.4% vs. 14.3%; p = 0.362). Conclusions: Antibiotic therapy alone proves to be effective and safe for pelvic abscesses, demonstrating a course similar to pericolic abscesses, even in the case of large abscesses. Although the analyzed patient cohort is small, this study provides additional evidence that percutaneous drainage is not always essential for treating this complication.