A 30-year-old woman with end stage renal disease received a cadaveric horseshoe kidney transplant. The horseshoe kidney embryologically represents the fusion of the lower poles of the kidneys in 95% of occasions. Another characteristic is the abnormal blood supply thought to be persistent from the embryonic period. Because each renal artery supplies its own area, there is no collateral circulation between the areas—an artery ligated by accident will always cause an infarction. This often happens in the fusion bridge, which receives its separate blood vessels from the distal aorta, or even the lilac artery.
*Department of Radiology, University of Texas Medical Branch, Galveston, Texas
†Department of Surgery, University of Texas Medical Branch, Galveston, Texas