Left renal vein hypertension as a cause of persistent gross hematuria.

Left renal vein hypertension as a source of persistent gross hematuria has been described in the literature. This type of hematuria is postulated to result from an elevation of left renal vein pressure leading to calyceal-venous communications. We report a case of left renal vein hypertension in which surgical and radiologic findings identify the cause of the hypertension as an aberrant peripheral nerve. To our knowledge, this etiology has never been described. A review of the literature with emphasis on the pathophysiology of renal-vein hypertension is also presented.