Major complex pelvic arteriovenous malformation in a patient with Down syndrome.

Pelvic arteriovenous malformations (AVM) are rare, and the treatment of this condition presents an interesting challenge. We report the first case of a major AVM in a patient with Down syndrome which was revealed by a massive hematuria. Arteriography showed a bilateral complex iliac artery malformation. The first proximal embolization (unilateral) did not prevent bladder hemorrhage, and the second distal (bilateral) immobilization produced bladder necrosis. However, the patient died despite an emergency cystectomy.