Causes of Ureteropelvic Junction Obstruction

Congenital abnormalities are the most common cause of UPJ obstruction in young children. The condition often results from an abnormality in the muscles that surround the UPJ. It may also be caused by an abnormality in the structure or position of the ureter, kidney, and renal blood vessels.

In older children, UPJ obstruction may be caused by the following:

  • Compression of the ureter caused by inflammation
  • Condition in which scar tissue forms in the renal cavity (retroperitoneal fibrosis)
  • Kidney stones
  • Scar tissue from previous surgery to correct UPJ obstruction

Publication Review By: Stanley J. Swierzewski, III, M.D.

Published: 09 Jun 1998

Last Modified: 13 Oct 2015