What is ureteral obstruction?

A ureteral obstruction is a blockage in one or both of the ureters. Ureters are the tubes that carry urine from the kidneys to the bladder. Ureters can become blocked for a variety of reasons.

A ureteral obstruction prevents urine from moving into your bladder and out of your body. If this blockage isn’t treated, urine can back up and damage your kidneys. This can cause pain and put you at risk of infection. In severe cases, a ureteral obstruction can lead to kidney failure, sepsis (life-threatening infection) or death.

How common is ureteral obstruction?

Ureteral obstructions are fairly common. They are more common in men over 60 because the prostate (a gland that only men have, located around the outflow of the bladder) becomes enlarged as men age. The enlarged prostate can block the flow of urine and result in buildup of urine in the bladder. It can also push up against the ureter and cause a blockage. Another form of bladder outflow blockage is by buildup of pressure in the urinary bladder because of an injury to the nerves or weak muscles—which makes it more difficult for the ureters to empty.

Other causes of blockages can include:

  • Kidney stones: This form of blockage is very common and can happen to both men and women. Kidney stones can affect young and old patients.
  • Scarring: When the tube that transfers urine from the kidney to the bladder is scarred on the inside, you can experience a blockage. This can also be caused by a birth defect.
  • Pressure from outside structures: You can also have a blockage when something outside of the ureter presses on it. This could be caused by a tumor or another nearby organ.

Who is affected by ureteral obstruction?

People of all ages can have a blocked ureter. Patients with kidney stones, can have a blockage at any age. These blockages can happen in both men and women. Older men with enlarged prostates can also affected. In babies and children who have a ureteral obstruction, the cause is usually a birth defect that affects their urinary tract.

What are the symptoms of ureteral obstruction?

Signs of ureteral obstruction reveal themselves in different ways. Patients who have stones may have severe pain. When the blockage is gradual and slow, it usually come on slowly and builds over time. In some cases symptoms may be mild at first, but can quickly get worse. Symptoms of a blocked ureter or urinary tract obstruction include:

  • Pain in your abdomen, lower back or sides below your ribs (flank pain).
  • Fever, nausea or vomiting.
  • Difficulty urinating or emptying your bladder.
  • Frequent urination.
  • Recurring urinary tract infections (UTI).
  • Urine that is bloody or cloudy.
  • Swollen leg(s).

How do people get ureteral obstruction?

There are many different reasons why the ureter can become blocked. Causes of a ureteral obstruction include:

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