[Embolic stroke due to ascending aortic thrombus in a patient with treatment-resistant ulcerative colitis].

The patient was a 49-year-old man presenting with recurrent melena due to progressive ulcerative colitis. One day, he developed left lower facial weakness and dysarthria, and the next day, he was transferred to our hospital because of muscle weakness in his left upper and lower extremities. On admission, neurological findings revealed left hemiplegia, including left facial palsy, dysarthria, and left hemispatial neglect. Brain MRI with diffusion-weighted image showed a fresh infarction in the right anterior and middle cerebral artery territory. Contrast-enhanced CT showed thrombus in the ascending aorta in addition to occlusion of the right internal carotid artery, suggesting the diagnosis of cerebral infarction with an embolic source in the aortic lesion. The intra-aortic thrombus disappeared after 48th day of antithrombotic therapy. Laboratory findings revealed elevated blood viscosity, proteinase-3-anti-neutrophil cytoplasmic antibody (PR3-ANCA), and β2GP1-IgG antibodies, suggesting that the cause of the aortic thrombus may be due to elevated blood viscosity and autoantibodies, as well as highly active ulcerative colitis.