Arterio-venous fistula with pseudoaneurysm of renal artery.

INTRODUCTION The authors describe a rare but potentially severe, sometimes even life-threatening complication occurring after various invasive renal interventions. The cause that gives rise to a fistula formation between close branches of renal artery and vein is an injury of these vessels during resection of a localised renal tumour, renal biopsy, percutaneous nephrostomy, and even blunt injury of the kidney. Blood flows under pressure from renal artery, pushes the surrounding renal parenchyma open, and creates a cavity varying in size and shape. This pseudoaneurysm may communicate with the collecting system of the kidney, in which case it may lead to haematuria, one of the typical symptoms of arteriovenous fistula. MATERIAL AND METHODS The authors observed this complication in 8 patients (6 males aged from 56 to 70, average 61.7, and two females aged 28 and 54). In 7 patients, the fistula developed after resection of a localised renal tumour, in one patient after percutaneous nephrolitholapaxy of a stone in the kidney. The fistulae manifested themselves between 7 an 21 days after surgery by massive haematuria in 4 patients and by intermittent macroscopic haematuria in 3 patients. In one patient the fistula was asymptomatic while the pseudoaneurysm at the place of pathological connection of renal veins was found during ultrasonographic examination after renal resection. RESULTS In all patients, the diagnosis of arteriovenous fistula and pseudoaneurysm of renal artery was achieved by ultrasonographic and/or CT examinations. The highest diagnostic value can be ascribed to digital subtraction renoangiography by Seldinger method that subsequently allowed active treatment by introducing an endovascular coil. By this method we cured 5 fistulae. In two patients, urgent nephrectomies were needed because of massive life-threatening haematuria. One of arteriovenous fistulae underwent spontaneous thrombosis. CONCLUSION The symptomatic arteriovenous fistula requires fast and precise diagnosis subsequently enabling efficient treatment. Endovascular manipulation is a method allowing the preservation of kidney affected by arteriovenous fistula with renal artery pseudoaneurysm (Fig. 7, Ref. 21).