• Renal dysplasia is a condition in which the internal structures of either one or both of the fetal kidneys do not develop normally in the uterus. Two thin, muscular tubes called ureters grow into the kidneys and branch out to form networks of small structures called tubules during normal development.
  • Renal dysplasia occurs when one or both kidneys do not develop properly while the fetus is growing in the womb. This is sometimes called polycystic dysplastic kidney or renal dysplasia. A typical adult has two kidneys.
  • Affected kidneys do not function normally. In other words, it does not function as well as a normal kidney. You may have cysts that are usually smaller than usual and look like fluid-filled sacs.
  • Renal dysplasia is a problem with intrauterine kidney development. Multiple cysts replace normal kidney tissue and cannot filter blood. The National Institute of Diabetes, Digestive and Kidney Diseases estimates that kidney dysplasia occurs in 1 in 4,300 newborns.
  • Renal dysplasia can be detected on prenatal ultrasound at 20 weeks before birth or shortly after birth. It can also be found in older children with some symptoms.
  • Affected kidneys are called dysplastic kidneys. Renal dysplasia rarely causes problems during pregnancy or childbirth.
  • When it occurs in one kidney, it is called unilateral renal dysplasia. If it happens in one kidney, it is called unilateral renal dysplasia. Although one of their kidneys won’t work properly, in most cases children have no serious problems. They will however need monitoring for possible long-term effects.
  • If this occurs in both kidneys, it is called bilateral renal dysplasia. This is more serious, and will even need follow-up during the pregnancy to find out how the baby is affected. 


What Causes Renal Dysplasia?

  • Genetic factors may cause renal dysplasia. Genes pass information to the child from both parents and determine the child’s characteristics. Sometimes parents can pass on a gene that is altered or mutated to cause kidney dysplasia. Genetic syndromes affecting multiple body systems can also cause renal dysplasia.
  • A syndrome is a group of seemingly unrelated symptoms or disorders that are thought to have the same genetic cause. Babies with inherited syndromes of kidney dysfunction may also have problems with the gastrointestinal tract, nervous system, heart and blood vessels, muscles and bones, or other problems with the urinary tract.
  • In the majority of cases, it is not caused by anything the mother did during her pregnancy and a future pregnancy is not likely to lead to renal dysplasia or other kidney problems. But the use of illegal drugs such as cocaine by pregnant women during pregnancy can also cause kidney dysplasia in the fetus.

How Common is Renal Dysplasia?

Renal dysplasia is a common condition. Scientists estimate that kidney dysplasia affects 1 in 4,000 children. Because some people with kidney dysplasia have never been diagnosed with the disease, this estimate may be underestimated. About half of children diagnosed with this condition have other urinary tract defects. 2 Rarely, polycystic kidney dysplasia has a familial history due to its genetic nature.

Who Is Most Likely To Have Renal Dysplasia?

Infants most likely to develop renal dysplasia include:

  • whose parents have the genetic features of this condition
  • with certain genetic syndromes affecting multiple body systems
  • whose mother used certain prescription or illegal drugs during pregnancy

What Are The Signs Of Renal Dysplasia?

Many children with renal hypoplasia have only one kidney with no signs of the disease. In some cases, the affected kidney may enlarge at birth and may cause pain.

What Are The Complications Of Renal Dysplasia? 

Complications of renal dysplasia may include

  • active hydronephrosis.
  •  Babies with renal hypoplasia with only one kidney may have other urinary tract abnormalities. When other urinary tract defects block the flow of urine, urine collects and causes the kidneys and ureters to swell, a condition called hydronephrosis. If left untreated, hydronephrosis can damage working kidneys and reduce their ability to filter blood. Kidney damage can lead to chronic kidney disease (CKD) and kidney failure. 
  • urinary tract infection (UTI). 
  • A blockage of urine can increase the risk of a UTI in the baby. Recurrent UTIs can also lead to kidney damage.
  • High Blood Pressure.
  • slightly increased risk of developing kidney cancer. 

How Is Renal Dysplasia Diagnosed?

  • Health care providers can diagnose renal hypoplasia during a woman’s pregnancy with a fetal ultrasound, also known as a fetal ultrasound. Ultrasound uses a device, called a transducer, that broadcasts painless, safe sound waves from organs to create images of their structures. An ultrasound is done to visualize and check the growth of the fetus in the uterus. 
  • Fetal ultrasound is a test done during pregnancy to create pictures of the fetus in the womb. A specially trained technician performs the procedure in a healthcare provider’s office, emergency care center, or hospital, and an obstetrician or radiologist explains the procedures. 
  • Sometimes the doctor will notice an abnormality in the fetus’s kidneys. However, ultrasound does not always detect renal hypoplasia before the baby is born. An obstetrician is a doctor who specializes in pregnancy and childbirth. A radiologist is a doctor who specializes in medical imaging. 
  • The patient – in this case, the mother of the unborn baby – does not need anesthesia for this procedure. Imaging can show defects in the fetus’s kidneys and other parts of the urinary tract.


  • Your doctor may detect renal dysplasia during a routine ultrasound or while checking for another condition. Usually, renal dysplasia occurs in only one kidney. In this case, the child will have limited symptoms and problems as he grows up.
  •  If there is renal dysplasia in both kidneys, treatment and monitoring will be required. There is also a chance that the fetus will not survive the pregnancy. 

How Is Renal Dysplasia Treated?

If the condition is limited to one kidney and the baby shows no signs of renal dysplasia, treatment may not be needed. However, your baby should have regular checkups, including

  • blood pressure check.
  • blood tests to measure kidney function.
  • a urine test to look for albumin, a protein commonly found in the blood. Albumin in the urine can be a sign of kidney damage.
  • perform periodic ultrasounds to monitor damaged kidneys and make sure that working kidneys continue to grow and remain healthy.


If both kidneys are affected, close monitoring is needed to determine the extent of kidney function. If the kidneys don’t work at all, babies who survive pregnancy will need a kidney transplant or dialysis to stay healthy.

How To Prevent Renal Dysplasia?

Researchers have not yet found a way to prevent hereditary renal dysplasia or specific genetic syndromes. Pregnant women can prevent renal dysplasia by avoiding certain prescription or illegal drugs during pregnancy. Maintaining a good diet and abstaining from certain medications during pregnancy can help prevent medical conditions, such as renal dysplasia, from developing in your baby. Pregnant women should consult their healthcare provider before taking any medication during pregnancy.

People who are more likely to develop renal dysplasia include:

  • Children whose parents have features of renal hypoplasia
  • children with other genetic syndromes
  • children exposed to illicit drugs and certain prescription drugs in utero

What Is The Long-Term Outlook For A Child With Renal Dysplasia Of Both Kidneys? 

  • The long-term outlook for a child with bilateral renal dysplasia is different from the long-term outlook for a child with uni renal dysplasia. A child with renal dysplasia in both kidneys are more likely to develop CKD.
  • This child should be closely monitored with a pediatric nephrologist, a doctor who specializes in the care of children with kidney disease. Children living in areas where a pediatric nephrologist is not available can see a nephrologist who treats both children and adults and may eventually require dialysis or a kidney transplant.

Can Renal Dysplasia Be Cured Completely?

There is no cure for renal dysplasia except when the good kidneys begin to fail and a kidney transplant or dialysis is recommended. This is usually only considered when the kidneys are causing pain, causing high blood pressure or abnormal changes during an ultrasound scan.

How Long Can You Live With Renal Dysplasia?

If your child has renal hypoplasia on one kidney, their outlook is usually good. The child may experience some health problems, such as an increased risk of UTIs, but they will most likely live a normal life.

Is Renal Dysplasia Serious?

A polycystic dysplastic kidney has no function and nothing can be done to save it. This condition usually affects only one of the kidneys, with the other healthy kidney usually growing larger to compensate for the cyst.

What Are The Two Types Of Renal Dysplasia?

Unilateral renal dysplasia

In unilateral renal dysplasia, a kidney does not develop properly in the uterus. (“One side” means one side.) Most children born with a hypoplastic kidney have no complications and do not need special treatment. Sometimes the remaining kidney becomes larger than normal to compensate for the dysplastic kidney. However, they may be at risk for urinary tract infections (UTIs) and/or hypertension (high blood pressure) later in life.

Bilateral renal dysplasia

In bilateral renal dysplasia, both kidneys do not develop normally. (“Bilateral” means bilateral.) Some babies born with two dysplastic kidneys have no immediate complications. Others need more support at birth, including ventilation to help them breathe.

All children with bilateral renal dysplasia should be monitored, as some may develop kidney failure. It sometimes occurs when a baby or a child is young, but it is more likely to happen later in life, especially during puberty when children’s bodies are developing rapidly. Children should return to the hospital or clinic during childhood to check that their kidneys are working properly. Treatment can be started as soon as needed to help your baby grow and stay healthy. Eventually, the kidneys may stop working and dialysis may be required.









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