Ectopic Kidney

What is an ectopic kidney?

An ectopic kidney is a birth defect in which a kidney is located in an abnormal position. In most cases, people with an ectopic kidney have no complaints. In other cases, the ectopic kidney may create urinary problems, such as urine blockage, infection, or urinary stones. Researchers estimate that ectopic kidney occurs once in every 1,000 births.

What are the kidneys?

Kidneys are bean-shaped organs, each about the size of your fist. Most people have two kidneys located near the middle of the back, just below the rib cage. The kidneys filter wastes and extra fluid from your blood. The wastes and extra fluid become urine, which drains from the kidneys to the bladder through tubes called ureters. Urine is stored in the bladder until it is released from the body when you urinate.

What causes an ectopic kidney?

During fetal development, a baby's kidneys first appear as buds inside the pelvis, near the bladder. As the fetal kidneys develop, they climb gradually toward their normal position near the rib cage in the back. Sometimes, one of the kidneys fails to make the climb. It may stop after making part of the climb. Or it may remain in the pelvis. Rarely does a child have two ectopic kidneys.

Some kidneys climb toward the rib cage, but one may cross over so that both kidneys are on the same side of the body. When a crossover occurs, the two kidneys may grow together and become fused.

What are the symptoms of an ectopic kidney?

An ectopic kidney may not cause any symptoms and may function normally, even though it is not in its usual position. Many people have an ectopic kidney and do not discover it until they have tests done for other reasons. Sometimes, a doctor may discover an ectopic kidney after feeling a lump in the abdomen during an examination. In other cases, an ectopic kidney may cause abdominal pain or urinary problems.

What are the possible complications of an ectopic kidney?

When a kidney is out of the normal position, drainage problems are likely. Sometimes, urine can even flow backwards from the bladder to the kidney, a problem called vesicoureteral reflux, or simply reflux. Abnormal urine flow can set the stage for a number of problems.

What tests will the doctor order?

Your doctor can get the most information about your condition by looking at pictures of the ectopic kidney. Several different imaging tests are available.

In addition to imaging tests, the doctor may order blood tests to determine how well your kidneys are working. These tests are almost always normal in patients with an ectopic kidney, even if it is badly damaged, because the other kidney usually has completely normal function.

What are the treatments for an ectopic kidney?

If your urinary function is normal and the doctor finds no blockage, no treatment for ectopic kidney is needed. Your doctor should continue to monitor your condition in case a change occurs.

If tests show that obstruction is present, you may need surgery to correct the position of the kidney to allow for better drainage of urine. To correct reflux, the surgeon may reattach the ureter to the bladder so that urine can't reflux into the kidney.

If extensive kidney damage has occurred, the surgeon may need to remove the kidney. As long as the other kidney is working properly, losing one kidney is not a problem. Many people live a normal life after donating a kidney for transplant. Some people are even born with only one kidney and lead full, healthy lives without discovering their condition.

With the right testing and treatment, if needed, an ectopic kidney should cause no serious long-term health problems.