Ureteral Stricture Facts

April 15, 2025

This page was reviewed under our medical and editorial policy by Kevin G. Chan, M.D., clinical professor, division of urology and urologic oncology, Department of Surgery, City of Hope^® Cancer Center Duarte

The ureter is a muscular tube that carries urine from the kidney to the bladder. A ureteral stricture is an unusual narrowing of this tube that may cause damage to the kidney over time.

What Is the Ureter?

The ureter transports urine from the kidneys, where it's collected in an area called the renal pelvis (or pelvis of the kidney), to the bladder. The renal pelvis is the point where the ureter enters the kidney and widens into a funnel shape. It's connected to the ureter at a point called the ureteropelvic junction.

After it leaves the renal pelvis, the ureter passes behind the other organs in the abdomen in a space called the retroperitoneum. It then goes toward the bladder, running parallel to the aorta and inferior vena cava (the main vein that brings blood back from the legs). Finally, the ureter connects to the bladder at a site called the ureteral orifice.

What Is Ureteral Stricture?

A ureteral stricture is a narrowing of the ureter. This narrowing may cause an obstruction, which prevents the kidney from functioning normally and may cause more significant damage over time. A ureteral stricture may also lead to dilation of the kidney (known as hydronephrosis) — a condition where urine collects in the kidney and causes the organ to stretch abnormally.

Ureteral Stricture Causes

The most common cause of a ureteral stricture is a congenital obstruction, meaning an obstruction that is genetically inherited and present from birth. However, ureteral strictures may also be caused by certain other health conditions, injuries or treatments.

Some of the causes of ureteral strictures include those listed below.

A congenital obstruction: Usually discovered in early childhood, a congenital obstruction is the most common cause of a ureteral stricture. It may occur at the point where the ureter enters the bladder (the ureteral orifice) or at the point where the ureter meets the kidney (the ureteropelvic junction).

Kidney stones: Strictures may also be caused by passing a kidney stone or by surgery to remove kidney stones.

Other surgical procedures: An iatrogenic ureteral stricture is a stricture that happens as the result of another abdominal surgery. Most often, any injury caused during surgery is repaired at the same time, however, some injuries may only be discovered later.

Radiation therapy: Receiving radiation therapy for certain abdominal cancers may lead to narrowing of the ureter.

Retroperitoneal fibrosis: This condition, which may cause scar tissue to develop in the retroperitoneum (the cavity at the back of the abdomen) and may also lead to a narrowing of the ureter.

A malignant obstruction: Certain kinds of advanced cancers can put pressure on the ureter, causing it to narrow. While this is not technically a ureteral stricture, it may cause similar symptoms.

Common Sites of Ureteral Strictures

Ureteral strictures may affect different parts of the ureter. Where a stricture develops usually depends on what is causing it, as detailed below.

Ureteropelvic junction (UPJ) obstructions: These are usually a congenital problem that may not be diagnosed until adulthood. The symptoms include pain in the back, infections and kidney stones.

Proximal ureteral strictures: These occur close to the top of the ureter and kidney. They are generally associated with kidney stones or having undergone previous procedures to repair ureteropelvic junction obstructions.

Pan-ureteral strictures: These are those that extend from the kidney to the bladder, or that cause narrowing at multiple sites along the ureter. They are most commonly seen in patients who have recurrent kidney stones.

Distal ureteral strictures: These occur close to the bladder or at the ureteral orifice. They can be caused by injuries, kidney stones or radiation therapy to the pelvic organs. Distal ureteral strictures at the ureteral orifice are usually congenital or occur during treatment for bladder tumors.