Top of the page
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).
Some of the common symptoms are:
Some people have no symptoms.
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.
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.
Current as of: March 1, 2023
Author: Healthwise Staff
Medical Review:Kathleen Romito MD - Family Medicine & Christopher G. Wood MD, FACS - Urology, Oncology
Care instructions adapted under license by your healthcare professional. If you have questions about a medical condition or this instruction, always ask your healthcare professional. Healthwise, Incorporated disclaims any warranty or liability for your use of this information.
©2006-2023 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.