Retroaortic Left Renal Vein: Three Case Reports

A left renal vein passing behind the abdominal aorta is termed a retroaortic left renal vein (RLRV). RLRV is a relatively uncommon congenital anomaly. It has been suggested the RLRV can sometimes cause symptoms such as hematuria and abdominal/flank pain. We report three patients with this anomaly: one case of type I RLRV and two cases of type III RLRV. Abdominal pain, flank pain, fever and hematuria were the major symptoms and signs in our cases. The urological symptoms were probably due to the increased pressure of the LRV, secondary to posterior nutcracker phenomenon. RLRV can be easily diagnosed by using ultrasound, computed tomography or magnetic resonance imaging; however, ultrasound is the most convenient imaging modality.