Pediatric Kidney Disorders

A multicolored toy caterpillar with a smile on its face.

Our team at OHSU Doernbecher Children’s Hospital offers advanced expertise in treating children and teens with kidney disorders.

You’ll find:

  • The most complete pediatric kidney services in Oregon.
  • Providers who specialize in treating children’s kidney conditions.
  • The latest minimally invasive treatment options, including robot-assisted surgery.

Understanding kidney disorders

What do the kidneys do?

The kidneys are two fist-size organs just below the rib cage that:

  • Filter waste and pass it as urine.
  • Regulate minerals in the blood.
  • Keep fluids in the body balanced.
  • Produce hormones important to red blood cells, blood pressure and bone health.

Kidney anatomy

A diagram showing the anatomy of the human kidneys.

Types of kidney disorders

Most children with kidney disorders are born with them. Often, the kidneys function normally. Other times, a disorder can lead to serious health problems. With treatment, most children with kidney disorders can live full lives.

Types include:

  • Congenital kidney disorders are those a child is born with.
  • Acute kidney disorders, such as kidney stones, strike suddenly and are usually successfully treated.
  • Chronic kidney disorders are ongoing conditions that can worsen over time.

Horseshoe kidney and pelvic kidney

Horseshoe kidney

Horseshoe kidney, also called renal fusion, is a birth defect that occurs in about 1 in 500 babies. The kidneys fuse at the lower end during fetal development, forming a U. They also may not move as high as normal kidneys.

About one-third of children with horseshoe kidney have one or more other conditions, such as fluid on the brain (hydrocephalus) or spina bifida.

Horseshoe kidneys may work normally. However, some children have complications, increasing the risk of kidney damage, such as:

  • Kidney stones
  • Urinary tract infections
  • Swollen kidneys
  • Urine backing up into the kidneys

Pelvic kidney

Pelvic kidney, a birth defect also known as ectopic kidney, happens when the kidney doesn’t move up during fetal development. A kidney can also move to the other side of the body. It affects about 1 in 1,000 children.

Many children with this condition have kidneys that work normally. Others have problems with urine flow, which can cause infections, a swollen kidney, and kidney damage. If the kidney sits especially low in the body, your child may need to wear protective gear to prevent injury during sports or other activities.

Signs of horseshoe and pelvic kidney

Horseshoe and pelvic kidney can cause complications such as urinary tract or kidney infections, kidney stones or backed-up urine. These may result in:

  • Fever, chills or nausea
  • Sharp pain in the back, side or lower abdomen
  • Pain while urinating
  • Cloudy or bloody urine
  • Changes in urination frequency

Diagnosing horseshoe and pelvic kidney

Horseshoe kidney may show up on an ultrasound before your baby is born. But most of the time, these conditions aren’t found until your child has tests for something else. Tests include:

  • Blood tests
  • Urine tests
  • Ultrasound
  • X-ray with contrast dye

Learn more about our urology tests.

Treating horseshoe and pelvic kidney

Your child probably doesn’t need treatment if the kidneys work fine. In unusual cases, with kidney damage or persistent complications, we may recommend surgery.

Our pediatric urologists offer expertise in minimally invasive methods. Options include moving a pelvic kidney or moving the ureter (the tube that connects the kidney to the bladder).

Duplex kidneys and ureters

Duplex kidneys and ureters are also called a duplex collection system. One or both kidneys have two tubes (ureters), not one, draining to the bladder.

This is a birth defect and is usually found in childhood. It affects about 1% of the U.S. population, and it’s more common in girls. Causes are unclear but may be genetic.

    Types of duplex kidneys and ureters

    • Incomplete: The two ureters are separate leaving the kidney but join at some point and enter the bladder as one.
    • Complete: The two ureters remain separate between the kidney and bladder.

    Related conditions

    Duplex ureters may be small or malformed, leading to complications. These can also happen in children without duplex kidneys and ureters:

    • Ureterocele: The ureter’s opening into the bladder is so small that urine collects above it. The end of the ureter balloons, usually inside the bladder.
    • Vesicoureteral reflux: Urine flows back into the kidney, sometimes because of a ureterocele. This may result in a kidney infection or kidney damage.
    • Ectopic ureter: One of the ureters isn’t connected to the bladder properly. This can cause urine to drain outside the bladder. It usually goes into the urethra, which carries urine outside the body. In girls, it can leak into the vagina.

    Signs and symptoms

    If both ureters are connected to the bladder, children usually don’t show symptoms. When they do, symptoms can include:

    • Back or side pain
    • Dribbling or difficulty urinating
    • Urinary tract infections
    • Kidney infections
    • High blood pressure

    Diagnosing duplex kidneys and ureters

    Duplex kidneys and ureters are usually found during tests for other conditions, such as an ultrasound. Your child’s doctor may recommend further tests, such as blood tests or an X-ray that uses dye put into the bladder.

    Treating duplex kidneys and ureters

    The kidneys and ureters themselves typically need no treatment. But complications may need treatment, such as antibiotics for infections or surgery for more serious conditions. Our pediatric urologists are experts in minimally invasive techniques such as laparoscopy, with only two small incisions.

    Surgical options include:

    • Endoscopy: This may be used to treat a ureterocele. A thin tube with a camera is guided through the urethra into the bladder. The balloon of urine is drained with a small incision.
    • Ureteral reimplantation: The surgeon attaches an ectopic ureter to the bladder.
    • Partial nephrectomy: Part of the kidney connected to an ectopic ureter is removed.
    • Ureteropyelostomy: An ectopic ureter in the upper kidney is connected to the normally functioning lower kidney. Urine then flows normally through the remaining ureter.
    • Flap valve: The surgeon lengthens the ureter where it connects to the bladder. This lets urine flow from the kidney but not back up into the bladder (vesicoureteral reflux).

    Learn more

    For families

    Call 503-346-0640 to:

    • Request an appointment.
    • Seek a second opinion.
    • Ask questions.


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    Doernbecher Children’s Hospital
    700 S.W. Campus Drive
    Portland, OR 97239
    Map and directions

    We also offer locations in Eugene and Salem.

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