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Hydronephrosis is a condition in which a baby's urine doesn't flow like it should through the urinary system. Urine can back up into the kidneys and cause swelling. Ultrasounds can reveal hydronephrosis before birth. Sometimes doctors discover it after birth.

In many children who are diagnosed prenatally, the condition disappears by the time of birth or soon after.

Hydronephrosis isn't a disease in itself. It's a secondary condition that results from another underlying disease. If continued after birth, or if noticed in other young children, a doctor may perform testing to determine why it is present.

Who gets hydronephrosis?

Hydronephrosis occurs in about one in 100 babies. It is one of the most common diagnoses on prenatal imaging.

What causes hydronephrosis?

Other underlying conditions cause hydronephrosis. For babies, causes might include blockage of the kidney or bladder, urine backing up from the bladder to the kidney, urinary tract infection or other diseases that can cause inflammation of the urinary tract.

What are the symptoms of hydronephrosis?

Hydronephrosis may or may not include symptoms. If present, the main symptom is pain, either in the side, back or abdomen. Abnormal flow of urine also increases the chances your child can get a urinary tract infection. Such infections are a common complication of hydronephrosis.

How is hydronephrosis diagnosed?

If your doctor diagnoses hydronephrosis in your baby before birth, your medical team might administer appropriate tests after birth. Often, your child might have a kidney and bladder ultrasound performed shortly after birth. An ultrasound uses sound waves to create an image of the child's kidneys and bladder. Your child's doctor may prescribe low-dose antibiotics to prevent urinary infections while more testing is being done.

Other tests might include a bladder X-ray and a renal (kidney) scan to determine how the kidneys are functioning.

Early diagnosis is important. Your child's kidneys can be permanently damaged if the condition is left untreated for too long.

How is hydronephrosis treated?

Hydronephrosis is treated by addressing the underlying disease or cause. Most children do not require surgery, as they often outgrow the underlying condition over the first few months to years of life.  After careful review of your baby's initial testing, you and your child's doctor will create a plan and discuss the role of surgery in your child's care.  In rare cases, your baby may need to have surgery during infancy to correct the problem.

What is the long-term outlook?

If your child receives treatment early, the outlook is excellent. However, if hydronephrosis is left untreated, the affected kidney may be permanently damaged and lose all function.

More information on hydronephrosis

We're here to help.

If your child has been diagnosed, you probably have lots of questions. We can help. If you would like to schedule an appointment, refer a patient or speak to our staff, please call our offices.

Call 682-303-0376