Your urinary tract is made up of your kidneys, ureters, bladder, and urethra. The actions of these structures are coordinated to remove toxins, wastes, and excess fluid from your body. When a blockage occurs that prevents urine outflow or causes a backflow, the urine builds up and your kidneys become enlarged. This condition is called hydronephrosis.*

What are the symptoms of hydronephrosis?

Hydronephrosis doesn’t always cause noticeable symptoms. When it does, those symptoms can include:

• Fever
• Nausea
• Pain in the side, back, abdomen, and/or groin
• Pain during urination 
• Increased urge to urinate 
• Increased frequency of urination
• Incomplete urination 
• Incontinence (loss of bladder control) 

The presence and severity of symptoms can depend on the cause and severity of the blockage.

What causes hydronephrosis?

A urinary blockage resulting in hydronephrosis is usually caused by an underlying condition, such as:

• Blood clot
• Kidney stone
• Abnormality present at birth
• Adhesion (scar tissue) 
• Tumor (cancerous or noncancerous)
• Enlarged prostate 
• Pregnancy
• Urinary tract infection (UTI) or other inflammatory condition

How is hydronephrosis diagnosed?

In addition to testing blood and urine samples, a hydronephrosis diagnosis is usually achieved by using one or more of the following imaging tests:

• Ultrasound 
• X-rays 
• Computerized tomography (CT)
• Magnetic resonance imaging (MRI) 

Your doctor may also perform a cystoscopy, in which a long tube with a light and camera mounted at the end is used to view the inside of your urethra and bladder.

What is the treatment for hydronephrosis?

Treating hydronephrosis typically involves treating the cause of the condition. Depending upon the situation, this may mean:

• Taking antibiotics
• Having your bladder mechanically drained
• Undergoing surgery or some other procedure

If the underlying cause is a kidney stone, it can either be passed on its own or severe enough to require surgical removal. Regardless of the cause, hydronephrosis should be treated in a timely fashion, as it can lead to kidney damage and possibly kidney failure. Recovery is likely when the condition is identified and addressed early.

*National Kidney Foundation. (2020, June 12). Hydronephrosis. https://www.kidney.org/atoz/content/hydronephrosis