Uretero-iliac Artery Fistula: A rare, life-threatening condition

Uretero-iliac artery fistula is an uncommon finding, which typically occurs following abdominal surgery, trauma, radiation, or ureteral stent placement. This usually presents in a patient with intermittent hematuria, making it difficult to diagnosis. Computed tomography angiography (CTA) is gold-standard for diagnosis, but a high-degree of clinical suspicion must be present to make the diagnosis. This often does not occur until there is massive hemorrhage leading to anemia and, not uncommonly, can be fatal. There are multiple proposed mechanisms of fistula formation, which are discussed here. We present a case of nonfatal fistula formation and the difficulties of diagnosing the condition.