Rare origin of supernumerary renal vessels supplying the lower pole of the left kidney.

The current observations have documented rare vascular anomalies in the right and left kidneys from a male and female cadaver, respectively. In the female left kidney in addition to being supplied by the normal renal artery and vein it contained a left lower polar renal artery and vein. The polar artery took origin from the inferior mesenteric artery to supply the lower pole and was drained by the left lower polar vein that opened into the left common iliac vein. The right kidney from a male cadaver showed supernumerary renal arteries and veins. The supernumerary upper renal artery took origin from the aorta and after a short course it gave rise into a cranial branch that took a long course to supply the lower pole and a caudal branch that entered the right kidney at the hilum. The supernumerary lower renal artery also took origin from the aorta and passed to supply the lower pole of the right kidney. Therefore, the lower pole of the right kidney received two arteries, but was not associated with a polar vein. The right kidney in addition to the normal right renal vein contained a supernumerary right renal vein. The vein was seen at the hilum and was the most posterior structure; passing behind the supernumerary lower renal artery to open into the posterior surface of the inferior vena cava. The anomalies described in the current observation present a unique pattern of congenital renal vascular abnormalities that may be of surgical importance.