Gastroenterology clinical image challenge: An 80-year-old woman presented with signs of lower GI bleeding under oral anticoagulation with apixaban. Previous history was significant for chronic atrial fibrillation, cholecystectomy and right hemicolectomy owing to colon ascendens cancer (UICC stage 2) one year before. Although her hemoglobin levels were only 6.7 g/dL, upper endoscopy was unremarkable. The initial ileocolonoscopy revealed large amounts of fresh blood and clots with a maximum at the surgical anastomosis. However, at the time no clear-cut bleeding source could be determined. Capsule endoscopy excluded a potential bleeding site in the higher small bowel, indeed reproducing the finding of fresh blood at the anastomosis.
Repeat ileocolonoscopy after apixaban cessation and regular preparation revealed some small black pigmented lesions just above the side-to-end ileotransversostomy tightly adhering to the mucosa resistant to exuberant water flushing (figure). In addition, some of the lesions appeared to submerge into the deeper colonic wall and were surrounded by subtle ulcerative reaction most likely representing the bleeding source.
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