Intra-abdominal bleeding as a rare complication after colonic endoscopic mucosal resection in a patient taking direct oral anticoagulants.

We describe the case of an 84-year old female who was taking rivaroxaban 30 mg/day and had a medical history of atrial fibrillation. She underwent endoscopic mucosal resection of a 5-mm adenoma located in the hepatic flexure of the transverse colon. Following the procedure, she developed gradually intensifying abdominal pain, with the appearance of small amount of blood in the feces. For that reason, she visited our facility on the 5th day post-endoscopic mucosal resection. At the time of the visit, contrast-enhanced abdominal computed tomography revealed no extravasation or free air; however, bloody ascites was confirmed in the peritoneal cavity. Thus, the patient was diagnosed with post-endoscopic mucosal resection intra-abdominal hemorrhage and hospitalized the same day. After admission, rivaroxaban was discontinued and patient condition monitored. Because subsequent abdominal computed tomography revealed no distinct increase in bloody ascites, no interventional radiological or surgical procedure was performed, and the patient was discharged after providing only conservative treatment. While hemorrhage and perforation are the main complications after colonic endoscopic mucosal resection, so far, there have been a few reports on the occurrence of intra-abdominal hemorrhage following endoscopic mucosal resection. Emergency treatment is sometimes required in patients with intra-abdominal hemorrhage. It is important to keep in mind that this complication, although very rare, may occur, particularly in patients taking anticoagulants.