To assess the effectiveness of EUS-guided transmural drainage in the treatment of postoperative intra-abdominal abscesses.

Retrospective evaluation of endoscopic treatment results in all patients with intra-abdominal abscesses following abdominal surgery between 2018 and 2023 at the Department of General, Gastroenterological and Oncological Surgery, Collegium Medicum, Nicolaus Copernicus University in Toruń, Poland. Patients were divided into two groups based on the time between surgery and the initiation of endoscopic treatment. The first group consisted of patients in whom EUS-guided transmural drainage of intra-abdominal abscesses was performed within 14 days of surgery. The second group consisted of patients in whom endoscopic treatment was initiated 14 days after surgery.

All 37 patients with intra-abdominal abscesses underwent active transmural (transgastric) EUS-guided drainage via a single approach. The first group included 21/37 (56.76%) and the second group included 16/37 (43.24%) patients with intra-abdominal abscesses. In both groups, intra-abdominal abscesses were a complication following urgent laparotomy for purulent or fecal peritonitis caused by colonic pathology. Active endoscopic drainage was performed for 6 (4-12) days in the first group and for 14 (7-22) days in the second group (p<0.05). Complications of endoscopic treatment were noted in 3/21 (14.29%) patients in the first group and in 2/16 (12.5%) in the second group (p=NS). Clinical success (resolution of clinical symptoms and complete regression of the abscess) was achieved in 20/21 (95.24%) patients in group 1 and 13/16 (81.25%) patients in group 2 (p<0.05). Long-term treatment success (no abscess recurrence in subsequent CT scans) was achieved in 19/21 (90.48%) patients in group 1 and 12/16 (75%) patients in group 2 (p<0.05).

EUS-guided transmural drainage seems effective treatment for postoperative intra-abdominal abscesses. Early endoscopic drainage is associated with better endoscopic outcomes in this group of patients.