Ureteral Strictures

What is ureteral strictures?

A ureteral stricture is an abnormal narrowing of a ureter. The ureters are the two thin, muscular tubes that carry urine from each kidney down to the bladder. When part of a ureter becomes scarred or squeezed, urine cannot drain freely. It backs up toward the kidney, causing the kidney to swell. Doctors call this swelling hydronephrosis. If the blockage lasts long enough, the kidney on that side can lose function.

People often ask, what is ureteral strictures in plain terms? The simplest answer is that it is a scarred, tight segment in the drainage pipe of a kidney. Strictures can be short or long, partial or nearly complete, and may affect one ureter or, less commonly, both. They can develop at any age, but in adults they are most often seen in people who have had kidney stones, previous surgery or procedures on the urinary tract, radiation therapy to the pelvis, or certain infections. In children, a narrowing where the ureter joins the kidney or the bladder is more often present from birth.

Ureteral strictures are usually managed by urologists, the specialists in kidney, bladder and urinary tract conditions. At Acibadem, this condition is evaluated and treated within the urology department, often working with radiologists and kidney specialists.

Ureteral strictures symptoms

Ureteral strictures symptoms vary widely. Some people have clear, sudden pain. Others have no symptoms at all, and the narrowing is found by chance on a scan done for another reason. The kidney can quietly lose function over months or years in these silent cases, which is why follow-up imaging matters after any known injury to the ureter.

Common symptoms include:

• Flank pain – a dull ache or sharp pain in the side or back, between the ribs and the hip, on the affected side
• Pain that comes and goes, sometimes worse after drinking large amounts of fluid
• Blood in the urine (hematuria), which may be visible or found only on a urine test
• Repeated urinary tract infections, because trapped urine is more likely to become infected
• Fever and chills when infection develops above the blockage
• Nausea or vomiting during episodes of severe pain
• Reduced urine output, mainly if both ureters are narrowed or if the person has only one working kidney
• High blood pressure, which can develop when a kidney is under long-term pressure

How symptoms feel often depends on how fast the narrowing formed. A stricture that develops quickly after an injury or procedure tends to cause noticeable pain because the kidney swells rapidly. A stricture that forms slowly, for example after radiation, may stretch the kidney gradually and cause little or no discomfort. Strictures near the kidney tend to cause flank pain, while narrowing near the bladder may also cause a need to urinate more often or discomfort low in the abdomen. If the affected kidney has already lost most of its function, symptoms may fade, which does not mean the problem has resolved.

Causes and risk factors

Ureteral strictures causes fall into two broad groups: intrinsic, meaning the problem is in the wall of the ureter itself, and extrinsic, meaning something outside the ureter is pressing on it. Most acquired strictures are the result of scar tissue forming after the lining of the ureter has been injured or inflamed.

Frequent causes include:

• Kidney stones – a stone that sits in the ureter for a long time can irritate the wall and leave scar tissue after it passes or is removed
• Previous procedures on the ureter – ureteroscopy (passing a thin telescope into the ureter), stone removal or stent placement can occasionally injure the lining
• Surgery in the abdomen or pelvis – operations on the uterus, bowel, blood vessels or prostate lie close to the ureters, and the ureter can be cut, clamped, stitched or have its blood supply disturbed
• Radiation therapy to the pelvis for cancers of the cervix, prostate, rectum or bladder, which can cause scarring that appears months or years later
• Infections – including tuberculosis of the urinary tract and, in some regions, the parasitic infection schistosomiasis
• Tumors – a cancer of the ureter itself, or a tumor nearby that presses on or grows into the ureter
• Retroperitoneal fibrosis – a rare condition in which scar-like tissue forms behind the abdominal organs and wraps around the ureters
• Congenital narrowing – present from birth, most often at the junction between the kidney and the ureter
• Kidney transplantation – the transplanted ureter has a delicate blood supply and can narrow over time

Risk factors are situations that make a stricture more likely rather than direct causes. They include a history of multiple stone episodes, repeated instrumentation of the urinary tract, prior pelvic radiation, previous pelvic or abdominal surgery, long-term urinary infections, and having a kidney transplant. Smoking is a known risk factor for cancers of the urinary tract, which can in turn cause a stricture. Not everyone with these risk factors will develop a narrowing, and some people develop a stricture with no obvious cause.

Ureteral strictures diagnosis

Ureteral strictures diagnosis starts with a conversation about symptoms, past surgeries, stone history, infections and any radiation treatment. A physical examination may show tenderness over the kidney. Because symptoms overlap with stones, infection and other conditions, imaging and laboratory tests are needed to confirm a stricture and to judge how much it is affecting the kidney.

Tests your doctor may use include:

• Urine tests – to look for blood, infection or abnormal cells
• Blood tests – including creatinine, a waste product that rises when overall kidney function falls
• Ultrasound – a painless scan that shows whether the kidney is swollen with trapped urine; it is often the first imaging test but does not always show the exact point of narrowing
• CT urography – a CT scan performed with a contrast dye that is filtered by the kidneys and outlines the ureters, showing where and how long the narrowing is and whether a stone or tumor is present
• Retrograde pyelography – during cystoscopy (a telescope examination of the bladder), the doctor injects dye up the ureter from below and takes X-rays; this gives a detailed picture of the stricture
• Antegrade pyelography – dye is injected through a small tube placed into the kidney through the skin, useful when the ureter cannot be reached from below
• Nuclear medicine renal scan – a scan that measures how much each kidney is working and how well it drains; this helps decide whether the kidney is worth saving
• Ureteroscopy – direct inspection of the ureter with a thin telescope, sometimes with a biopsy (tissue sample) if a tumor is suspected

To call a narrowing a true stricture, doctors generally look for a fixed segment that does not open up, combined with evidence that urine is held back above it. The renal scan is important because a kidney that has lost almost all function may be better managed differently from one that is still working well. If there is any concern about cancer, tissue sampling and further staging scans may be arranged before treatment is chosen.

Ureteral strictures treatment options

Ureteral strictures treatment options depend on where the stricture is, how long it is, what caused it, how well the kidney is working, and the person’s overall health. There is no single right approach, and your urologist may discuss more than one option. The goals are to relieve the blockage, protect kidney function and, where possible, restore normal drainage without a permanent tube.

Observation. A very mild narrowing that is not causing swelling of the kidney, pain or infection may simply be monitored with periodic ultrasound and kidney function tests. This is more common when the stricture was found by chance.

Relieving the blockage urgently. If there is infection above the blockage or the kidney is severely swollen, the first step is often to drain it. This may be done with a ureteral stent, a soft hollow tube placed through the bladder that keeps the ureter open, or with a nephrostomy tube, a thin tube placed through the skin of the back directly into the kidney. Both are usually temporary measures that buy time for the infection to settle and for planning.

Medication. Medicines do not remove scar tissue, but they play a supporting role. Antibiotics treat infection, pain relief is given during acute episodes, and medicines to control blood pressure may be needed. In retroperitoneal fibrosis, medicines that reduce inflammation are often part of the plan alongside drainage.

Endoscopic (telescope-based) procedures. For short strictures, treatment through natural passages without any external incision is often tried first. Balloon dilation involves passing a deflated balloon across the stricture and inflating it to stretch the narrowing. Endoureterotomy involves making a controlled cut through the scar from inside using a small blade or laser, after which a stent is left in place for several weeks while the ureter heals in a wider shape. These procedures have shorter recovery times, but the stricture can return, particularly if it is long, dense or caused by radiation, and repeat treatment may be needed.

Reconstructive surgery. When endoscopic treatment fails or the stricture is long, surgeons may remove the scarred segment and rebuild the ureter. Common operations include ureteroureterostomy (cutting out the narrowed piece and stitching the healthy ends together), ureteral reimplantation (reattaching the ureter to the bladder, sometimes with a flap of bladder tissue to bridge a gap), pyeloplasty (reshaping the junction between the kidney and ureter), and, for very long defects, replacing a segment with a piece of the person’s own intestine or tissue from the inside of the cheek. In selected cases the kidney may be moved lower in the abdomen to reduce the gap. Many of these operations can be performed through small incisions using laparoscopic or robot-assisted techniques, which may mean less pain and a shorter hospital stay for suitable patients; more information about the approach is available on the robotic surgery page. Open surgery through a larger incision remains appropriate in some situations.

Long-term stents or tubes. Some people are not well enough for major surgery, or the stricture is caused by an advanced cancer. In these cases a stent or nephrostomy tube that is exchanged at regular intervals can keep the kidney draining indefinitely.

Removing the kidney. If the affected kidney has lost nearly all its function and the other kidney is healthy, removing it (nephrectomy) may be considered, especially if it causes recurrent infections or pain. This is a decision made carefully with your specialist team.

Recovery varies with the procedure. After endoscopic treatment, most people return to normal activities within days, with a stent removed in the clinic a few weeks later. After reconstructive surgery, a stent is usually kept in place while the repair heals, and follow-up imaging is scheduled to confirm the ureter is draining well. Stents can cause bladder irritation, urgency and mild blood in the urine while they are in place; these effects usually settle after removal.

Living with ureteral strictures and outlook

The outlook for ureteral strictures depends heavily on the cause and the health of the kidney at the time of treatment. Short strictures from stones or minor procedure-related injury often respond well to endoscopic treatment or surgical repair, and many people recover normal drainage. Longer strictures, and those caused by radiation or poor blood supply, are harder to treat and more likely to come back. Strictures caused by cancer follow the course of the cancer itself.

Because scar tissue can slowly re-form, follow-up is a normal part of care. Your doctor may arrange ultrasound scans and blood tests at intervals for a year or more after treatment, sometimes longer, to catch any return of narrowing before the kidney is harmed again. Some people need more than one procedure over time.

Day to day, most people with a treated stricture live without restriction. Staying well hydrated, treating urinary infections promptly, and following any advice on preventing kidney stones can support kidney health. If you have a stent in place, your doctor will explain what to expect and when it must be changed or removed; a forgotten stent can itself cause serious problems. People with reduced kidney function may be advised to avoid certain medicines that stress the kidneys and to have their blood pressure monitored. Living with a long-term nephrostomy tube involves learning to care for the skin site and drainage bag, and nursing support is usually offered for this.

Frequently asked questions

What is ureteral strictures in simple terms?

A ureteral stricture is a narrowed, scarred section of the tube that carries urine from a kidney to the bladder. Because urine cannot pass easily, it builds up and stretches the kidney. Over time this pressure can damage the kidney, so the narrowing is usually treated once it is confirmed.

What are the most common ureteral strictures symptoms?

Flank or back pain on one side is the most frequent complaint, often coming and going. Blood in the urine, repeated urinary infections, fever, and nausea during painful episodes are also common. Some people have no symptoms, and the narrowing is discovered only on a scan, which is one reason follow-up imaging is advised after ureter injury.

What are the main ureteral strictures causes?

Most acquired strictures are caused by scar tissue forming after the ureter is injured or inflamed. Kidney stones, procedures inside the ureter, pelvic or abdominal surgery, and radiation therapy are the leading causes in adults. Less often, tumors, infections such as tuberculosis, or a condition called retroperitoneal fibrosis are responsible. Some strictures are present from birth.

How is ureteral strictures diagnosis confirmed?

Doctors usually start with an ultrasound to see whether the kidney is swollen, then use a CT scan with contrast dye or X-rays taken while dye is injected into the ureter to pinpoint the narrowing. A nuclear medicine scan measures how well the kidney is working, and a telescope examination with biopsy may be added if cancer is a concern.

What are the ureteral strictures treatment options?

Options range from monitoring a mild narrowing, to temporary stents or drainage tubes, to procedures done through a telescope such as balloon stretching or laser cutting of the scar, to reconstructive surgery that removes the scarred segment and rejoins healthy tissue. The choice depends on the length and location of the stricture, its cause and how well the kidney is functioning.

Can a ureteral stricture come back after treatment?

Yes, it can. Scar tissue may re-form, particularly after balloon dilation or in strictures caused by radiation. Surgical reconstruction generally has a lower chance of recurrence than endoscopic treatment for longer strictures, but no approach can guarantee the narrowing will never return. Regular follow-up scans are used to detect any recurrence early.

Is a ureteral stricture dangerous if left untreated?

It can be. Ongoing blockage may lead to permanent loss of function in the affected kidney, and trapped urine is prone to infection, which can become serious. If both ureters are affected, or a person has only one kidney, overall kidney function can fall. Early evaluation and treatment aim to prevent these outcomes.

When to see a doctor

Persistent pain in the side or back, visible blood in the urine, or urinary infections that keep returning should be discussed with a doctor, especially if you have a history of kidney stones, urinary tract procedures, pelvic surgery or radiation. Anyone who has been treated for a stricture should keep the follow-up appointments and scans that were recommended.

Seek urgent medical care if you notice any of the following red-flag signs:

• Fever, chills or shaking together with flank pain, which may indicate infection in a blocked kidney
• Severe pain that is not relieved by usual pain medicine or that comes with repeated vomiting
• Passing very little or no urine, particularly if you have one kidney or a known problem on both sides
• Heavy bleeding in the urine or urine with large clots
• Confusion, rapid breathing, dizziness or feeling faint, which can be signs of a serious infection spreading to the bloodstream
• A nephrostomy tube that stops draining, falls out or has a red, swollen or leaking skin site
• Pain, fever or inability to pass urine after a stent has been placed

These situations can worsen quickly and need prompt assessment so that the kidney can be drained and any infection treated.