Crossed fused renal ectopia with a single ureter: a rare anomaly.

A rare case of crossed fused renal ectopia is presented where the fused kidneys were present on the right side and there was a single ureter opening into the right side of the bladder. To the best of our knowledge, this variant of crossed fused ectopia has not been reported previously. This case challenges the embryological theory that deviation of one of the ureteric buds to the opposite side results in crossed fused renal ectopia.