Understanding Ectopic Kidneys

An ectopic kidney is a birth defect where a kidney is out of place. It often causes no symptoms but may affect urine flow, leading to complications. Treatment is needed if it causes problems.

What is an ectopic kidney?

An ectopic kidney is a kidney that is out of place.  An ectopic kidney is caused by a birth defect.

What causes an ectopic kidney?

An ectopic kidney happens while a baby is growing in the womb. Normally, the kidneys form a kidney bud within the pelvis (hip bones). When a signal is released from the kidney tissue, the kidneys should move into their position behind the ribcage.

In the case of an ectopic kidney, one of the kidneys does not move to the right place. It may remain in the pelvis. It may move upward but stop before it reaches its usual position. It may move higher than its normal position. A kidney may even cross over so that both kidneys are on the same side of the body. Sometimes it may even connect with the second kidney. Some of the causes for this birth defect are:

  • Genetic defects: Genes carry information. A genetic defect is a problem within the genes when the baby is growing within the womb. It is passed from the parents to the child. It may cause issues with many organs and other processes in the body.
  • Defects in the kidney tissue that would normally “tell” the kidneys to move into position
  • Under developed kidney.
  • An infection, illness, or substance that disturbs a baby’s growth in the womb. It is usually something the mother is exposed to during pregnancy. Certain chemicals, drugs, or diseases can do this.

Are there symptoms of an ectopic kidney?

Most people do not have symptoms. The kidney may function normally, even though it is not in right place. Most often, people only find out by accident that they have an ectopic kidney, usually when they are tested for other illnesses or health concerns. In some cases, an ectopic kidney could cause pain in the abdomen (stomach area). It may also cause urinary problems. Most people live a full and normal life without ever really knowing they have an ectopic kidney.

What are the complications of having an ectopic kidney?

The most common complication involves the flow of urine. Your urine comes from the kidneys and flows down into the bladder through tubes called ureters. In an ectopic kidney, this process may not work as well. The urine may back up in your kidney. If it is serious enough, it causes a problem called vesicoureteral reflux (VUR).

When the flow of the urine becomes a problem, the following issues may occur:

  • Urinary tract infection (UTI). Normally, urine washes out germs. This keeps them from growing. But if urine stays in the urinary tract too long, germs can grow and spread. That can cause infections.
  • Kidney stones. A kidney stone is a hard object that forms from chemicals in the urine. If urine stays too long in the urinary tract, these chemicals may have time to form stones.
  • Kidney damage: The kidneys can get damaged from infections. If infections happen too often, or are left untreated, it can lead to kidney failure.
  • Hydronephrosis: When the urine is blocked, it builds up in the kidney. This causes swelling. It is called hydronephrosis. VUR can cause hydronephrosis.

What is the treatment for an ectopic kidney?

An ectopic kidney only needs treatment if it causes problems with your urine flow. If this is the case, your healthcare provider will need to evaluate your kidney. If the problem is caught soon enough, your healthcare provider can treat it. This includes treating the infection, removing the blockage, or fixing the urine flow before kidney damage happens. Sometimes surgery may be needed. This can correct the position of the kidney. That will lead to better drainage of urine.

If the kidney is severely damaged and not working properly, your healthcare provider may suggest removing it. This will only be done if your other kidney is working well.

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This content is provided for informational use only and is not intended as medical advice or as a substitute for the medical advice of a healthcare professional.
© 2024 National Kidney Foundation, Inc.