Safety and efficacy of endoscopic ultrasound-guided pelvic abscess drainage with lumen-apposing metal stents for complicated acute diverticulitis

Background and aims: Endoscopic ultrasound-guided pelvic abscess drainage (EUS-PAD) with lumen-apposing metal stents (LAMS) is an alternative approach for post-surgical and inflammatory pelvic collections. We assess the safety and efficacy of EUS-PAD with LAMS in a large population of complicated acute diverticulitis (AD). Methods: We retrieved consecutive patients who underwent EUS drainage attempts for complicated AD from 2019-2023 in three referral centers. All cases have been considered suitable for EUS-PAD after multidisciplinary discussion. Continuous variables are expressed as median [interquartile range]. Results: Sixty-six patients were retrieved; in 13 cases EUS-PAD was not indicated since no or small abscess was found. Fifty-three patients (29 female; age 74 [62-83] year-old] were finally included. Forty (75.5%) patients had pelvic abscess, while 13 (24.5%) had a para-colonic abscess, with a median size of 50 [40-60] mm. Trans-rectal and trans-colonic EUS-PAD were performed in 34 (64.2%) and 19 (35.8%) cases, respectively. Technical and clinical success rates were 92.5% and 88.7%; incidence of adverse events was 3.8% (one bleeding, one late migration). LAMS were removed after 19 [14-28] days. Median follow-up was 12 [8-12] months. Four (7.5%) patients underwent urgent Hartmann sigmoidectomy, while 12 (22.6%) patients required elective surgery; two (3.8%) patients presented recurrent diverticular abscesses. No procedure-related or disease-specific mortality was observed. Conclusion: EUS-PAD could be considered a safe and effective rescue strategy in case of failed or contraindicated percutaneous approach for the management of complicated AD to reduce the need for urgent surgery. Comparative data is necessary to confirm these observations.