Abstract
We report a case of a 49-year-old man with acquired renal arteriovenous fistula (RAVF) caused by blunt renal injury. The patient fell down stairs and hit his right lower back, his lower back pain worsened, and therefore he consulted a local hospital 5 days after injury. The doctor diagnosed renal injury, and the patient was transferred to our hospital. Contrast-enhanced computed tomography (CT) revealed subcapsular hematoma and small renal parenchyma hematoma, corresponding to type Ib renal injury according to the Japanese Association for the Surgery of Trauma 2008 classification. His pain and hematuria improved and he was discharged from hospital 13 -days after injury. However, 29 days after injury his hematuria reappeared. Contrast-enhanced CT imaging findings suggested RAVF. However, because his vital signs were stable , he returned home. After another 4 days, his hematuria worsened, and therefore we performed angiography. Selective renal arteriography revealed RAVF and a pseudoaneurysm in the upper part of his right kidney. Transcatheter arterial embolization (TAE) was performed for the fistula with a coil and his hematuria improved. In mild renal injury as in the present case, it is routine to observe and not perform surgery. However, if hematuria caused by blunt renal injury remains, we must consider the possibility of RAVF or a pseudoaneurysm. TAE was useful in the present case.
