Hydronephrosis—Adult
Condition
Definition
Hydronephrosis is a backup of urine in one or both kidneys. This leads to swelling and pressure in the tube that connects the bladder and kidneys. It needs care right away.
Causes
Hydronephrosis happens when urine cannot drain from the kidney to the bladder. It may be caused by a blockage from:
- Kidney stones
- Blood clots
- Growths or tumors
- Scarring from an accident or surgery
- An enlarged prostate
- Pregnancy
- A urinary tract infection
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Risk Factors
Things that may raise the risk of hydronephrosis are:
- Having any of the health problems that cause the condition
- Cancer treatments
- Neurogenic bladder
Symptoms
Some people do not have symptoms. Those who do may have:
- Pain in the back, waist, lower belly, or groin
- Problems urinating, such as:
- Pain
- Urgency
- Urinating more or less than usual
- A bladder that does not feel emptied after passing urine
- Fever
- Nausea and vomiting
Diagnosis
The doctor will ask about symptoms and health history. A physical exam will be done. You may need to see a doctor who treats kidney diseases.
Blood and urine tests will be done to look for problems with how the kidneys are working.
Pictures of the kidneys may be taken. This can be done with:
- Ultrasound
- X-rays
- CT scan
- MRI scan
A cystoscopy may also be done. It uses a lighted scope to view the bladder.
Other tests will be done to find a cause.
Treatment
The cause of hydronephrosis will need to be treated. This will allow urine to flow as it should. Some options are:
- Fixing defects in the kidney
- Removing a kidney stone that will not pass on its own
- Medicines to treat infection or ease pain
- Inserting a tube to drain excess urine
- Taking out of all or part of the kidney (rare)
Prevention
The risk of hydronephrosis may be lowered by managing health problems that can harm the kidneys.
National Institute of Diabetes and Digestive and Kidney Diseases
National Kidney Foundation
CANADIAN RESOURCES:
Health Canada
The Kidney Foundation of Canada
National Institute of Diabetes and Digestive and Kidney Diseases
National Kidney Foundation
CANADIAN RESOURCES:
Health Canada
The Kidney Foundation of Canada
References
- Hydronephrosis. Cleveland Clinic website. Available at: https://my.clevelandclinic.org/health/diseases/15417-hydronephrosis.
- Hydronephrosis. National Kidney Foundation website. Available at: https://www.kidney.org/atoz/content/hydronephrosis.
- Hydronephrosis. NHS Choices website. Available at: https://www.nhs.uk/conditions/hydronephrosis.
- Nephrolithiasis in adults. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/nephrolithiasis-in-adults-24.
- Nuraj, P and Hyseni, N. The diagnosis of obstructive hydronephrosis with color doppler ultrasound. Acta Inform Med. 2017 Sep; 25(3): 178–181.
- Obstructive uropathy. Merck Manual Professional Version website. https://www.merckmanuals.com/professional/genitourinary-disorders/obstructive-uropathy/obstructive-uropathy.
Contributors
- Mark S. Itzkowitz, MD, JD
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