Renal arteriovenous fistula after renal biopsy: a case report and literature review.

Acquired renal arteriovenous fistulas (AVF) are rare conditions in which an anomalous connection arises between the arterial and venous systems. Renal AVFs can be classified into three main groups: idiopathic, congenital, and acquired, the last of which are the most common. Incidence has been increasing, due to the growing number of renal biopsies.