Abstract
We report a patient with history of recurrent invasive rectal adenocarcinoma complicated by obstructive uropathy requiring nephro-ureteral catheter placement. Two years later during a regular catheter exchange, the patient developed unusually bloody urine raising suspicion for possible vascular injury. CT angiogram and conventional angiogram were negative. However, an antegrade nephrostogram revealed a fistulous communication between the right ureter and the right internal iliac artery. Subsequently, the artery was sacrificed using detachable coils. We discuss the rare encounter of a silent arterio-ureteral fistula, the value of antegrade nephrostogram as a diagnostic tool, and the management options in such scenario.