Editorial Comment: Arterioureteral fistulas occur as a result of inflammatory or ischemic conditions involving the ureter, iliac vessels or both. Secondary (iatrogenic) causes such as surgery for pelvic malignancy or vascular reconstruction predominate (85%). Ureteral obstruction requiring chronic stent placement appears to hasten fistula development (often within 4 months). Massive or pulsatile gross hematuria during stent exchange should suggest the diagnosis. Intraureteral balloon catheter placement across the bleeding site is the first step. Selective iliac angiography often demonstrates pseudoaneurysm but sensitivity is less than 50%. Iliac arterial embolization with vascular bypass grafting has been the traditional surgical approach.1 However, because these patients are notoriously poor operative candidates, endovascular stent-graft technology has recently been attempted and is quickly emerging as a viable alternative to open surgical options, although long-term followup is lacking. The authors recommend proximal urinary diversion and stent removal in conjunction with arterial stent-graft placement as first line therapy. 1. Vandersteen, D. R., Saxon, R. R., Fuchs, E., Keller, F. S., Taylor, L. M., Jr. and Barry, J. M.: Diagnosis and management of ureteroiliac artery fistula: value of provocative arteriography followed by common iliac artery embolization and extraanatomic arterial bypass grafting. J Urol, 158: 754, 1997