BS P01 Case Report: Emergency Laparotomy for Retrograde Intussusception after Roux-en-Y Gastric Bypass

Abstract

Abstract Background Roux-en-Y gastric bypass (RYGB) is a common operation performed to treat obesity and associated co-morbidities. When done with weight management programs, it is associated with 60% excess weight loss. A rare complication is retrograde intussusception (RI), which can require emergency surgery due to risk of bowel ischaemia and necrosis. We report a case of a 66-year-old female who developed intermittent then acute RI, requiring urgent laparotomy for reduction of the intussusception and small bowel resection of the perforated invaginated segment. Her case is compared to the literature available, and a pathophysiological mechanism aiming to explain post-RYGB RI is proposed. Methods We compare the case of a patient with RI post-RYGB, to the available literature. The literature search was done on PubMed: “retrograde intussusception AND Roux-en-Y”. Results were limited to English language and human species. Paediatric and Maternity journals were excluded. The patient is a 66-year-old female who had a laparoscopic RYGB for obesity in 2018; and lost 106% excess weight. In 2022, she presented with laparoscopic evidence of a resolved intussusception. In 2023, she was re-admitted with CT and laparotomy-confirmed RI and small bowel obstruction at the jejuno-jejunal anastomosis. She was managed with small bowel resection and anastomosis. Results The non-specific clinical presentation of RI makes prompt diagnosis challenging. Usually, patients have abdominal pain and lack peritonism. Severe cases may present with bowel ischaemia, as the intussuscepted segment can have compromised vascularity. Hence, prompt diagnosis and timely management is essential to reduce morbidity and mortality. CT-AP is the diagnostic imaging test of choice, but delay in diagnosis of >48h may increase mortality to 50% due to delayed intervention. The surgical management is emergency surgery with gentle reduction of the intussusception. Resection of the invaginated small bowel segment with anastomosis may be indicated if there is bowel ischaemia. Conclusions We report the case of a patient with RI post-RYGB, with evidence of gut dysmotility prior to intussusception. The literature suggests that dysmotility disorders could underpin RI, as 80% of cases are anti-peristaltic. Obesity has a strong association with slow gastric and intestinal motility, likely due to impaired gut-brain biochemical messaging and altered gut microbiota. RYGB will disrupt these pathways, and we hypothesize that this may lead to further motility dysregulation. However, further research is necessary to provide supporting evidence. Nevertheless, this report provides a helpful reminder to prompt urgent investigation in patients who present with non-specific abdominal pain post-RYGB.