Ventriculo-peritoneal shunt pseudocyst causing ureteropelvic junction obstruction in a child with myelomeningocele and retrocaval ureter.

We report on a boy with myelomeningocele and a ventriculo-peritoneal shunt, who presented with progressive ureteropelvic junction obstruction and an enlarging right upper quadrant mass. Exploration revealed a large pseudocyst around the distal portion of the shunt, causing obstruction of an unsuspected retrocaval ureter. To our knowledge this is the first reported case of an upper urinary tract complication due to a ventriculo-peritoneal shunt as well as the first case of a retrocaval ureter associated with myelomeningocele.