Ureteropelvic Junction Obstruction

The Northwestern Medicine Congenital Urology Program provides comprehensive treatment and care for patients with Ureteropelvic Junction (UPJ) obstruction.

UPJ obstruction happens when there is a partial or total blockage in the location where the kidneys and the ureter, the tube that carries urine to the bladder, meet. The flow of the urine is affected as the urine builds up because of the blockage. The buildup can damage the kidneys.

The flow of your urine may be affected. UPJ causes urine to build up, which can damage the kidneys.

The condition is more common in children than adults. It often happens while a baby is developing in the womb.


  • Common symptoms for an adult include a sudden pain in the side, back or stomach. You may also feel upset to your stomach or vomit.
  • Hematuria (blood in the urine)
  • Kidney infection
  • Kidney stones
  • Children may have no symptoms


A UPJ obstruction can be diagnosed using imaging tests such as ultrasound and computerized tomography (CT) scans. To confirm an obstruction, a nuclear medicine scan may be done.


If the obstruction is large, surgery may be required. A procedure called a pyeloplasty removes the blockage that is keeping urine from reaching the bladder. This surgery may be done with a minimally invasive approach. The surgeon may use a robotic device to help with the surgery.