IMAGING

Arterioureteral fistulas: a clinical, diagnostic, and therapeutic dilemma
Madoff DC, Gupta S, Toombs BD, Skolkin MD, Charnsangavej C, Morello FA Jr, Ahrar K, Hicks ME
Division of Diagnostic Imaging, The University of Texas M D Anderson Cancer Center, Houston, Texas, USA
AJR Am J Roentgenol. 2004; 182: 1241-50

Review article: no abstract available

• Editorial Comment
  Arterioureteral fistula is a rare entity and a potentially life-threatening cause of hematuria with a 23% mortality rate. Although rare, it is being diagnosed more frequently because of the increase of predisposing factors such as radiation therapy and major surgery in the pelvis, presence of previous vascular surgery and presence of double-J-stent (1,2). These patients usually present intermittent episodes of gross hematuria. Arterioureteral fistula represents abnormal communications between a major artery and the mid or distal portion of the ureter. Frequently the fistula occurs between the external iliac artery and the ureter. This entity is a diagnostic challenge for the radiologist given the intermittent nature of the bleeding. Thus, various techniques have been used in attempt for its diagnosis: cystoscopy , intravenous urography, ureterography, abdominal and pelvic CT, renal arteriography, and selective iliac arteriography. Selective iliac arteriography although presents low sensitivity (less than 50%), is considered the most sensitive technique. The cause of false negative examination is due to the fact of examining the patient when the fistula is partially occluded by a thrombus(quiescent phase). True positive findings are arterial pseudoaneurysms at the point where the ureter crosses the iliac artery and gross extravasation of contrast material into the ureter. Classic treatment of this entity is based on open surgery, which is usually unsuccessful and frequently associated with increased morbidity and mortality. In patients explored surgically without a preoperative diagnosis, the mortality rate is 64% in comparison to 8%, when the correct diagnosis is made pre-operatively.
  Option treatments are quite variable: nephrectomy or nephroureterectomy, ureteral reconstruction, ureterostomy (surgical or percutaneous) or pyelonephrostomy, ligation of the ureter, embolization of the renal artery, renal irradiation, and autotransplantation. Recently a sonographically guided percutaneous nephrostomy followed by antegrade insertion of multiple metallic coils into the ureteral lumen just proximal to the fistula was reported. Vascular surgical procedures includes local reconstruction (i.e., arteriorrhaphy, patch closure, interposition graft, bypass), ligation with or without extra anatomic bypass (if arterioureteral fistulas arise from either common or external iliac artery), and ligation of the internal iliac artery.
  Recently successful endovascular treatment of arterioureteral fistula using graft covered stent have been described and it seems to be a promising alternative to surgical procedures because presents less morbidity and mortality. Long-term follow-up after this endovascular treatment technique is needed.

References
1. Marco Perez LM, Vigues Julia F, Trilla Herrera E, Dominguez Elias J, Ponce Campuzano A, Gonzalez Satue C, et al.: Hematuria secondary to arterioureteral fistula. Endovascular treatment. Actas Urol Esp. 2001; 25: 668-671.
2. Sherif A, Karacagil S, Magnusson A, Nyman R, Norlen BJ, Bergqvist D: Endovascular approach to treating secondary arterioureteral fistula, Scand J Urol Nephrol. 2002; 36: 80-82.

Dr. Adilson Prando
Department of Radiology
Vera Cruz Hospital
Campinas, São Paulo, Brazil