What Is a “Swollen Kidney”? A Guide to Bilateral Hydronephrosis

Enlarged kidneys can develop at any age, affecting not only adults and children but also the kidneys of prenatal infants. This swelling develops when the ureters used to drain the kidneys get blocked, causing a buildup of urine that leads to enlargement of the kidneys.

Bilateral hydronephrosis occurs when blockages develop in both kidneys. While a case of bilateral hydronephrosis may pose greater health concerns due to the impacted health and functioning of both kidneys, most cases of this condition can be remedied by identifying the underlying cause and seeking out treatment in a timely manner.

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What causes bilateral hydronephrosis?

Blockages leading to kidney hydronephrosis can have many different causes. In most cases, this condition develops in relation to another existing risk factor or illness. Common causes of hydronephrosis include the following:

  • Kidney stones
  • Urinary tract infections
  • Congenital blockages
  • Enlarged prostate
  • Tumors or cancer (particularly cancers in the lower abdomen affecting the bladder, prostate, colon or cervix)

In addition, hydronephrosis may be triggered by blood clots, scar tissue or pregnancy. However, this is far from a comprehensive list of illnesses and conditions that may cause kidney hydronephrosis. Bilateral hydronephrosis occurs when both kidneys are affected.

What are the symptoms of a swollen kidney?

One of the challenges of diagnosing hydronephrosis is that symptoms don’t always develop right away. While some cases of hydronephrosis are mild and pose no serious threat to your health, others may require medical intervention.

Typically, though, symptoms will develop if your kidney hydronephrosis becomes serious and requires a visit to a doctor or specialist. Here are some of the common symptoms:

  • Pain in one or both sides, including pain that extends into the lower abdomen and even the groin
  • Fever
  • Painful urination, frequent urination or other urinary issues
  • Nausea
  • Vomiting
  • Failure to thrive (in infants)
  • A bladder condition or injury preventing the bladder from being emptied

In most cases, pain will be the most common symptom of bilateral hydronephrosis. If you notice any of these symptoms, contact your doctor or a urologist to receive a diagnosis.

How do you treat an enlarged kidney?

In many cases, hydronephrosis is best treated by addressing the underlying cause of this condition. Infections, for example, can be treated with antibiotics to relieve the swelling and inflammation that is likely causing hydronephrosis. In cases where a kidney stone is causing the blockage, your doctor may recommend a wait-and-see approach to see if the stone is passed on its own.

In severe cases of an enlarged kidney, or in cases where the blockage isn’t resolved by treating the underlying health issue, a medical intervention may be necessary. Your doctor may recommend using a catheter to drain urine from the bladder, or even a special procedure to drain urine directly out of the kidney, if lasting kidney damage is a concern.

Ultimately, your doctor will want to manage the blockage and ensure that drainage is provided before the buildup of urine causes damage requiring dialysis or a kidney transplant. In a limited number of cases, this will involve using surgery to remove a blockage that won’t resolve on its own.

Is hydronephrosis a disability?

While severe cases of kidney hydronephrosis may be cause for alarm, hydronephrosis on its own will not cause disability. It is possible that, in some cases, untreated hydronephrosis will result in permanent kidney damage, which may result in a continued need for dialysis. It’s also possible that a severely swollen kidney will suffer so much damage that it needs to be removed, which may have a permanent impact on your quality of life.

Keep in mind, though, that such incidents are rare and unlikely to occur with proper medical treatment. The consequences of delaying medical assistance should serve as strong motivation to alert your doctor to any new symptoms that may suggest an enlarged kidney–especially if you’re currently dealing with another health condition that can increase your risk of hydronephrosis.

In some cases, an individual may develop a mild case of bilateral hydronephrosis that resolves itself before that person even realizes they’ve developed this condition in both of their kidneys. If you or your baby do develop symptoms, though, talk to your doctor or pediatrician right away. You might need to visit a urologist to determine the exact cause of your symptoms and to get an accurate diagnosis.



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