A case of gross hematuria arising during embolization for renal arteriovenous malformation.

A cirsoid type of arteriovenous malformation was treated successfully by superselective embolization using a platinum micro coil and absorbable gelatin sponge. During the procedure, as soon as the arteriovenous shunt had disappeared, an arteriopelvic shunt appeared. The pyelogram showed that the high pressure arterial blood flow drained directly into the pelvic cavity. Massive gross hematuria occurred immediately accompanied by a sudden blood pressure drop to 60 mm Hg, necessitating blood transfusion. Fortunately this complication was managed successfully. To our knowledge, there are only a few reported cases that make reference to gross hematuria occurring on embolization. We discuss the possible causes of this complication and the mechanism of occurrence of gross hematuria in renal arteriovenous malformation.