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Learning About Hydronephrosis

Kidneys, ureters, bladder

What is hydronephrosis?

Hydronephrosis is swelling of the kidneys. It is caused by a buildup of urine. This condition can happen if a tube that drains urine from your kidneys is blocked. The blockage can come from within the urinary tract or from pressure outside of the tract. Pregnancy is an example of an outside (external) cause.

This condition is often caused by a blockage such as a kidney stone, tumour, or blood clot. It also can be caused by a problem in your urinary system that you were born with (congenital problem).

What are the symptoms?

Some of the common symptoms are:

  • Pain in one or both sides.
  • Stomach pain.
  • Blood in your urine.

Some people have no symptoms.

How is it diagnosed?

Your doctor will do an ultrasound to look for a blockage in your urinary system. An ultrasound allows your doctor to see a picture of the organs and other structures in your belly (abdomen). You also may need blood and urine tests.

How is it treated?

Your treatment depends on the cause of the swelling. If it is caused by a blockage, your treatment will depend on the type of blockage you have. If the blockage is caused by a kidney stone, you may wait for the stone to pass. If hydronephrosis happens during pregnancy, it usually clears up on its own.

You may need to have urine drained from your bladder or kidneys. A urinary catheter is a small, flexible tube that can be inserted through the urethra and into the bladder, allowing urine to drain. A nephrostomy catheter is a thin tube placed into your kidney to drain urine. Sometimes surgery is needed to clear the blockage.

If you have a blockage, you should begin to feel better after the blockage is gone.

Many people recover and have no long-term problems. But some may have kidney damage. If hydronephrosis was left untreated for a long time, the damage can be severe. Severe damage will require further treatment.

Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor or nurse advice line (811 in most provinces and territories) if you are having problems. It's also a good idea to know your test results and keep a list of the medicines you take.

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