Arterial Thrombosis in Severe Ulcerative Colitis: A Case-Based Narrative Review of Current Evidence.

Inflammatory bowel disease is a recognized risk factor for venous thromboembolism, whereas arterial thrombotic events remain underappreciated despite their substantial clinical consequences. We report a 45-year-old man without significant comorbidities who developed severe ulcerative colitis complicated by diffuse arterial thrombosis, including cerebral infarctions, an ascending aortic mural thrombus, iliac artery thrombosis, and multi-organ infarctions. After stabilization with supportive care and anticoagulation, remission-directed ulcerative colitis therapy and a vascular safety-oriented maintenance strategy were initiated, including vedolizumab and individualized secondary thrombosis prevention. To contextualize this presentation, we integrate current evidence on the epidemiology, clinical phenotypes, underlying mechanisms, and risk factors for arterial thrombosis in inflammatory bowel disease, highlight disease activity as a dominant trigger, and summarize therapy-specific vascular safety considerations across IBD treatment classes.