Crossed ectopia of left vas deferens, leaving ipsilateral seminal vesicle in normal position

A 19-year-old man with crossed ectopia of the vas deferens was investigated with special reference to right hydronephrosis and renal dysfunction. There was no vesicoureteral reflux. The left kidney was hypoplastic or dysplastic and the left ureter emptied into the left seminal vesicle. The right malrotated hydronephrotic kidney was in the lumbar position. The right lower ureter communicated with either the right seminal vesicle or the ampullary portion of the left vas deferens and drained into the bladder at the normal site. The end of the right vas deferens was dilated. The left vas deferens crossed the midline and opened into the right seminal vesicle, leaving the ipsilateral seminal vesicle in the normal position. A search of the literature failed to reveal any similar anomalies.