Ureteropelvic junction (UPJ) obstruction occurs from partial or total blockage where the pelvis and ureter (the tube leading to the bladder) meet. More common in children and often resulting from a congenital abnormality, UPJ obstruction impedes the flow of urine, causing it to build up.
Symptoms do not always present themselves, even when a UPJ obstruction is present. When symptoms do occur, they may include:
Abdominal and flank pain
Nausea and vomiting
Urinary tract infections
High blood pressure
Over time, if UPJ obstructions go untreated, deteriorated kidney function can become a serious problem.
When the obstruction is mild, it is usually left to correct itself. Antibiotics may be used to prevent infection. Because there is the potential for kidney damage, more severe cases tend to require pyeloplasty, a surgical procedure that removes the blockage and reconnects the ureter and the renal pelvis.