Question: A 73-year-old man with a history of hypertension presented with the first attack of approximately 300 mL volume of hematochezia. The patient was afebrile with stable vital sign and physical examination was normal. The laboratory test showed that the hemoglobin level was 7.7 g/dL and serum platelet count, coagulation factors, and other chemistry tests were all within normal limits. There was no obvious bleeding source on esophagogastroduodenoscopy and colonoscopy. Computed tomography (CT) enterography demonstrated 2 long segments of jejunal and ileal aneurysmal dilatation, measuring about 6 and 4 cm in luminal diameter, with mild concentric wall thickening (Figure A, B, arrows).