Kidney Dysplasia

Kidney dysplasia at a glance

  • Kidney dysplasia is the enlargement of the kidney due to abnormal tissues that form fluid-filled cysts in one or both kidneys of a baby as it grows in the womb.
  • This damage to the kidney’s structure causes it to fail in its role of processing urine and purifying the body, requiring the child to live on one functioning kidney.
  • Kidney dysplasia (or multicystic dysplastic kidney) usually only occurs in one of the baby’s kidneys; in cases where it occurs in both kidneys the fetus usually dies before birth or can only live on dialysis or via a kidney transplant.
  • Kidney dysplasia affects 1 in 3,500 babies, although it may affect more because it often goes undiagnosed.
  • There is no treatment for most cases of kidney dysplasia.
  • Many of those affected with kidney dysplasia live normal lives with only one kidney, but do need to see a urologist regularly.

What is kidney dysplasia?

A dysplasia is the enlargement of an organ or tissue due to an increase in abnormal cells or tissue. Kidney dysplasia is a disease that begins before birth in the fetus and involves enlargement of the kidney. This swelling renders the kidney ineffective due to fluid-filled sacs (cysts) forming in place of normal kidney tissue.

With kidney dysplasia — also called renal dysplasia or multicystic dysplastic kidney — the kidney is malformed as the baby grows in the womb. The resulting child will usually have the disease throughout adulthood.

The kidneys play a vital role, filtering the body’s wastes from the blood stream and processing it into urine. This urine travels from the kidneys through ureter tubes to the bladder, then out of the body through the penis or vagina

In kidney dysplasia, as the baby develops in the womb the kidney’s structure is disrupted, causing malformation of the ureter tubes that makes the kidney incapable of processing urine. That urine in the kidney has nowhere to go and it forms cysts that shut down the kidney’s function.

Kidney dysplasia is diagnosed in only 1 in 3,500 babies. However, physicians think it actually affects many more because it has no symptoms and can often go undiagnosed.

Usually only one kidney is affected by kidney dysplasia. People can live with only one kidney, which generally adapts to take over the functions of the other kidney. The non-functioning kidney usually disappears and is absorbed in the body. In kidney dysplasia affecting only one kidney, the child’s long-term prognosis is excellent for a normal life with only one kidney, experiencing few to no health problems.

If both kidneys are affected by kidney dysplasia, the fetus spontaneously aborts because of a lack of amniotic fluid, which nurtures a normal pregnancy. This vital fluid is produced by the kidneys during gestation, and with no functioning kidneys to produce it, the pregnancy will not last. In rare cases, a baby with both kidneys affected by kidney dysplasia can be born and survive on immediate dialysis (a mechanical means of purifying body waste) or with a kidney transplant.

It is important for someone with kidney dysplasia to be under the care of a urologist because problems in the urinary tract can affect the normal kidney. A person with kidney dysplasia should not take any chances of something going wrong with the one functioning kidney.

Causes of kidney dysplasia

Most cases of kidney dysplasia are unpredictable and sporadic. Many biological events have to occur precisely for the kidneys to develop correctly, and just one anomaly in the process can result in kidney dysplasia.

There can be a genetic cause of kidney dysplasia, as it appears to be an inherited trait in some families. Some drugs taken by the mother during pregnancy can also lead to kidney dysplasia, such as some medications for blood pressure and seizures. Pregnant women should consult their physician about medications they are taking.

Diagnosis, treatment & complications of kidney dysplasia

Since kidney dysplasia does not cause any symptoms in the affected person’s health, it often goes undiagnosed. Diagnosis often occurs during an ultrasound exam of the fetus in the pregnant mother, using an x-ray-like machine that emits very high-frequency sound waves.

A physician may also feel an abnormal mass during a physical exam of the baby for a urinary tract infection or for some other problem.

There are no treatments for kidney dysplasia except in cases where the good kidney begins to fail and a kidney transplant or dialysis is recommended. This is usually only considered when the kidney causes pain, results in high blood pressure or shows abnormal changes when scanned by ultrasound.

Children and adults with kidney dysplasia should follow these precautions:

  • Regular checkups
  • Regular evaluations of blood pressure and kidney function
  • Urine testing for protein
  • Periodic ultrasounds to monitor the healthy kidney
  • Antibiotics for children with urinary tract infections.

Complications for people with kidney dysplasia include:

  • High blood pressure
  • Increased risk of kidney cancer (rare)
  • Kidney disease or failure in children with urinary tract problems.