Endoscopic transgastric necrosectomy for infected necrotizing pancreatitis extending from the lesser Sac to the paracolic gutter in a pediatric patient: a case report.

Endoscopic transgastric necrosectomy (ETN) has emerged as a preferred minimally invasive approach for managing walled-off necrosis (WON); however, its conventional indication remains confined to necrosis limited to the lesser sac. The applicability of this technique for extensive necrosis extending to the paracolic gutter and pelvic cavity remains poorly characterized, particularly in pediatric patients. We herein report the case of a 7-year-old boy with infected necrotizing pancreatitis, in whom imaging demonstrated necrosis extending from the lesser sac to the bilateral paracolic gutters, iliac fossae, and pelvic cavity. Following initial conservative management and CT-guided percutaneous drainage, endoscopic ultrasonography (EUS)-guided transmural drainage was performed at week 4, followed by ETN on day 40. During the procedure, the conventional indication was extended by leveraging the flexibility of the endoscope to navigate from the pancreatic tail into the left paracolic gutter and pelvic cavity, thereby achieving successful debridement without the need for additional percutaneous sinus endoscopy or video-assisted retroperitoneal debridement. The patient recovered uneventfully, with post-procedural CT confirming complete resolution and stents removed three months later. This case suggests that extended ETN may represent a safe and effective option for managing extensive WON beyond the lesser sac in children, potentially obviating the need for more invasive combined procedures.