A ureteral obstruction is a blockage in one or both of the tubes (ureters) that lead from the kidneys to the bladder. Ureteral obstruction can be a curable condition. However, if it's not treated, symptoms can quickly move from mild (pain, fever, infection) to severe (loss of kidney function, sepsis, even death).

  • Experience. Mayo Clinic urologists have extensive experience in treating ureteral obstructions, including minimally invasive procedures and robot-assisted surgery as well as ureteral reconstruction of all types, depending on your need.
  • Outcomes. As a high-volume center, Mayo Clinic has a long history of success using advanced procedures that improve your surgical outcomes and speed your recovery.
  • Comprehensive care. Urology and kidney specialists (nephrologists) work together to diagnose and treat your condition.
  • Research. Mayo Clinic researchers continue to evaluate new ways to treat ureteral obstructions.

Mayo Clinic in Rochester, Minn., ranks No. 1 for urology in the U.S. News & World Report Best Hospitals rankings. Mayo Clinic in Scottsdale, Ariz., and Mayo Clinic in Jacksonville, Fla., are ranked high performing for urology by U.S. News & World Report.

The job of the urinary system is to eliminate waste from the body. The normal urinary system consists of two kidneys, with a tube (ureter) connecting each kidney to the bladder and another tube (urethra) that drains urine from the bladder out of the body. A ureteral obstruction is a blockage that occurs anywhere in the tubes that carry urine from your kidneys to your bladder.

Certain conditions make you more likely to have a ureteral obstruction, including conditions present from birth (congenital), a tendency to make kidney stones or recent cancer surgery.

Duplication of the ureter. This common congenital condition causes two ureters to form on the same kidney. The second ureter can be normal or only partially developed. If either of these ureters doesn't function properly, urine can back up into the kidney and cause damage.

Ureteropelvic junction. This abnormality is a blockage in the connection between the kidney and ureter that stops urine flow and causes the kidney to swell and eventually stop working. This abnormality can be congenital, can develop with normal childhood growth, can result from an injury or scarring, or in rare cases, can develop from a tumor.

Ureterovesical junction. In this condition, the blockage occurs between the ureter and the bladder, causing urine to back up into the kidneys.

Ureterocele. When the ureter is too narrow and doesn't allow urine to flow normally, a tiny hernia (ureterocele) will develop, usually in the section of the ureter closest to the bladder. This hernia blocks urine flow, causing urine to back up into the kidney, which can damage the kidney.

Intrinsic or extrinsic ureteral obstruction. This condition refers to a blocked ureter by various causes inside the ureter (intrinsic) or outside the ureter (extrinsic). They might include:

  • Ureteral stones
  • Severe constipation, which happens primarily in children but also occurs in adults
  • Cancerous and noncancerous tumors
  • Internal tissue growth, such as endometriosis in females
  • Long-term swelling of the ureter wall, usually due to diseases such as tuberculosis or a parasite infection called schistosomiasis

Retroperitoneal fibrosis. This rare disorder occurs when fibrous tissue grows in the area behind the abdomen. The fibers may grow due to cancers or may result from taking certain medicines used to treat migraines. The fibers encircle and block the ureters, causing urine to back up into the kidneys.

Mayo Clinic works with hundreds of insurance companies and is an in-network provider for millions of people. In most cases, Mayo Clinic doesn't require a physician referral. Some insurers require referrals or may have additional requirements for certain medical care. All appointments are prioritized on the basis of medical need.

At Mayo Clinic in Arizona, specialists in urology and nephrology and hypertension treat ureteral obstructions in adults.

For appointments or more information, call the Central Appointment Office at 800-446-2279 (toll-free) 8 a.m. to 5 p.m. Mountain Standard Time, Monday through Friday or complete an online appointment request form.

At Mayo Clinic in Florida, specialists in urology and nephrology and hypertension treat ureteral obstructions in adults.

For appointments or more information, call the Central Appointment Office at 904-953-0853 8 a.m. to 5 p.m. Eastern time, Monday through Friday or complete an online appointment request form.

At Mayo Clinic in Minnesota, specialists in urology and nephrology and hypertension treat ureteral obstructions in adults and children.

For appointments or more information, call the Central Appointment Office at 507-538-3270 7 a.m. to 6 p.m. Central time, Monday through Friday or complete an online appointment request form.

At the Mayo Clinic Children's Center, specialists in pediatrics, urology, and nephrology and hypertension have expertise in diagnosing and treating ureteral disorders in infants and children.

For appointments or more information, call 855-MAYO-KID (855-629-6543) toll-free from 7 a.m. to 6 p.m. Central time, Monday through Friday or use an online appointment form below.

See information on patient services at the three Mayo Clinic locations, including transportation options and lodging.

Frequently, doctors diagnose ureteral obstruction disorders before birth during routine prenatal ultrasounds, which can show details of the developing fetus, including the kidneys, ureters and bladder. Doctors often perform another ultrasound after birth to reevaluate the kidneys.

If your doctor suspects you have an obstructed ureter, you may have some of these tests and scans to reach a diagnosis:

  • Blood and urine tests. Your doctor checks samples of your blood and urine for signs of infection and the presence of creatinine, which signals that your kidneys aren't working properly.
  • Ultrasound. An ultrasound of the area behind your abdominal organs (retroperitoneal ultrasound) allows your doctor to view the kidneys and ureters.
  • Voiding cystourethrogram. To test for abnormal urine flow, your doctor inserts a small tube (catheter) through the urethra, injects dye into your bladder, and takes X-rays of your kidneys, ureters, bladder and urethra before and during urination.
  • Intravenous pyelogram (IVP) or excretory urogram. Your doctor or a technician injects dye into a vein in your arm and takes X-rays as the dye moves into your kidneys, ureters and bladder.
  • Renal nuclear scan. Similar to an IVP, your doctor or a technician injects dye that contains a small amount of radioactive material into your arm. A special camera detects the radioactivity and produces images that your doctor uses to evaluate the urinary system.
  • Cystoscopy. A small tube with a camera and light is inserted into your urethra or through a small incision. The optical system allows the doctor to see inside the urethra and bladder.
  • Computerized tomography (CT) scan. A CT scan combines a series of X-ray views taken from many different angles and computer processing to create cross-sectional images of your kidneys, ureter and bladder.
  • Magnetic resonance imaging (MRI). Abdominal MRI uses a magnetic field and radio waves to create detailed images of the organs and tissues that make up your urinary system.

The goal of ureteral obstruction treatment is to remove blockages, if possible, or bypass the blockage, which may help repair damage to the kidneys. Because of the complexity of the urinary system, you may need more than one type of treatment.

Drainage procedures

A ureteral obstruction that causes severe pain may require an immediate procedure to remove urine from your body and temporarily relieve the problems caused by a blockage. Your doctor (urologist) may recommend:

  • A ureteral stent, which involves inserting a hollow tube inside the ureter to keep it open.
  • Percutaneous nephrostomy, which involves inserting a tube through your back to drain the kidney directly.
  • A catheter, which involves inserting a tube through the urethra to connect the bladder to an external drainage bag. This may be especially important if your bladder also plays a role in poor drainage of your kidneys.

Your doctor can tell you which procedure or combination of procedures is best for you. Drainage procedures may be temporary or permanent treatment options, depending on your condition. For instance, many people with kidney blockages have stents or percutaneous nephrostomies placed while receiving chemotherapy for cancer treatment, to ensure that their kidneys are functioning at their best during treatment.

Endoscopic surgery

Endoscopic surgery, a minimally invasive procedure, involves passing a lighted scope through the urethra into the bladder and other parts of the urinary tract. The surgeon makes a cut (incision) into the damaged or blocked part of the ureter to widen the area and then places a hollow tube (stent) in the ureter to keep it open. This procedure may be done to both diagnose and treat a condition.

Other surgical procedures

Surgical procedures to correct ureteral obstruction include:

  • Ureterolysis. Ureterolysis (u-ree-tur-OL-ih-sis) is a procedure that exposes the ureter and frees it from abnormal fibrous or scar tissues (adhesions).
  • Pyeloplasty. During pyeloplasty (PIE-uh-low-plas-tee), the surgeon reopens or repairs the ureter and inserts a hollow tube (stent) to keep the ureter open. The stent remains in place for up to six weeks and is removed during an office visit.
  • Partial nephrectomy. During a partial nephrectomy, the surgeon removes the damaged part of the kidney caused by the ureteral obstruction.
  • Ureterectomy. In this procedure, the surgeon removes all or part of a ureter, then reconstructs the urinary tract by lowering the kidney and stretching the bladder up or replacing the ureter using other body tissue.
  • Ureteral reimplantation. In this surgery, a poorly functioning section of the ureter is removed and the remaining healthy sections are reconnected and reattached to the bladder.
  • Transureteroureterostomy. During transureteroureterostomy (trans-u-ree-tur-oh-u-ree-tur-OS-tuh-me), the surgeon joins one ureter to the other, resulting in sustained improvement in long-term renal function.This procedure isn't recommended if you have stone disease or cancer in the ureters.

These surgical procedures may be performed through any one of these surgical approaches:

  • Open surgery, during which your surgeon makes an incision in your abdomen to perform the procedure.
  • Laparoscopic surgery, which is performed through a small tube with a light and a camera that allows your surgeon to see inside you. The surgeon makes one or more small incisions through your skin to insert the lighted tube and other instruments needed for the procedure.
  • Robot-assisted laparoscopic surgery, during which your surgeon uses a robotic system to perform a laparoscopic procedure.

The main differences among these surgical approaches are your recovery time after surgery and the number and size of incisions used for the procedure. Your doctor (urologist) determines the type of procedure and the best surgical approach to treat your condition.


Ureteral obstructions may be associated with infections that also need to be treated.

Your doctor may prescribe a single-dose of an antibiotic medication when you have a ureteral obstruction treatment procedure performed. A longer course of antibiotics may be needed if infection is a part of the original problem that damaged your kidneys. Antibiotics may also be recommended when a stent or percutaneous nephrostomy tube is removed.

If having a stent in place causes severe abdominal pain, which can sometimes happen, your doctor may prescribe an alpha blocker to manage this side effect.


See a list of publications by Mayo Clinic doctors on ureteral obstructions on PubMed, a service of the National Library of Medicine.

Feb. 15, 2014