S5294 Novel Use of EUS-Guided Diverting Gastroduodenostomy in a Patient With Chronic Gastric Outlet Obstruction and Ulcerations Due to Post-Surgical Deformity of the Stomach With Inverted J-Shaped Positioning

Introduction: Retrosternal colonic interposition is a standard procedure for patients, particularly children, with damage/underdevelopment of the esophagus. However, many long-term complications have been reported, including gastric outlet obstruction (GOO). GOO may lead to ulceration, perforation, and fistula formation. Traditional surgical revisions can be challenging in patients with complex anatomy. We present a case highlighting the novel use of endoscopic ultrasound (EUS)-guided gastroenterostomy to treat GOO and a gastrocutaneous fistula in a patient with a significant post-surgical gastric deformity. Case Description: A 54-year-old woman with a history of esophagectomy and retrosternal colonic interposition following caustic ingestion as a toddler presented with 1 month of oral intolerance, abdominal pain, and chest wall erythema that progressed to a draining cutaneous opening. She had recently been diagnosed at another hospital with GOO and a gastrocutaneous fistula. Initial esophagogastroduodenoscopy (EGD) showed an esophago-colonic anastomotic stricture (11 mm) with ulceration. A second anastomosis at 38 cm showed friable mucosa and a 5 × 5 mm fistulous tract. Biopsies were benign. The stricture was dilated to 18 mm. Fluoroscopy revealed severe gastric malpositioning, with the fundus displaced inferiorly toward the pelvis and the pylorus positioned superiorly and contralateral to the ulcerated site, forming an inverted J-shape. EUS-guided gastroenterostomy was performed by accessing the most dependent portion of the stomach, puncturing the stomach wall and small bowel via 22-gauge needle, and deploying a 15 × 15 mm lumen-apposing metal stent (LAMS) to create a gastrojejunostomy. Follow-up EGD showed the fistula, which was cauterized. Closer with an over-the-scope clip was unsuccessful due to fibrosis. Discussion: The gastrojejunostomy effectively diverted gastric content away from the ulcerated anastomosis, allowing the fistula to close spontaneously. The patient remained on total parental nutrition (TPN) and proton pump inhibitors for 3 weeks before initiating oral intake. She gradually advanced to a full diet. Repeat EGD at 2 and 4 months showed a closed fistula and a well-positioned, patent LAMS. This case demonstrates a successful, minimally invasive management strategy for post-surgical GOO and fistula formation in the setting of extreme gastric malrotation. EUS-guided bypass avoided the need for high-risk surgical intervention in a complex anatomical landscape.