Left renal haematuria by compression of an unusual vein.

A 55-year-old female had an episode of massive haematuria. An abnormal venous branch was under compression just before it joined a persisting left inferior vena cava. The main renal vein was not occluded and peri-ureteral varices had not been formed. Although it is a complicated anomaly which has not been reported, a variety of venous abnormalities might be responsible for unexplained renal haematuria.