Pyelectasis and Pelviectasis

Pyelectasis, or pelviectasis, is when urine gathers in the center of the kidney, called the pelvis. This makes the kidney larger than normal. This condition can affect one or both kidneys.

What is Pyelectasis or Pelviectasis?

Pyelectasis, or pelviectasis, is when urine gathers in the center of the kidney, called the pelvis. This makes the kidney larger than normal. This condition can affect one or both kidneys.

Pyelectasis/pelviectasis happens in about 1% of all pregnancies. It affects males more than females.

What Causes Pyelectasis or Pelviectasis?

In most cases, the cause of pyelectasis, or pelviectasis, is not known. It is usually not related to any major medical problems. However, there are some conditions that can cause it, including:

  • Ureteropelvic junction obstruction (UPJO)
  • Vesicoureteral reflux  

What are the Signs and Symptoms of Pyelectasis or Pelviectasis?

Signs pyelectasis, or pelviectasis, can usually be seen on the 20-week prenatal ultrasounds. This shows that the pelvis of the kidney is bigger than normal.

How is Pyelectasis or Pelviectasis Diagnosed?

A 20-week anatomy ultrasound can diagnose pyelectasis or pelviectasis.

How is Pyelectasis or Pelviectasis Treated?

You will have an ultrasound every 4 weeks to watch the condition until your baby is born. Treatment depends on the cause of the condition and how severe the swelling is. In most cases, the swelling goes away on its own, and no other treatment is needed. If the condition is caused by a severe blockage or reflux, surgery may be needed to fix the issue. 

Possible Problems

Your baby will be watched for hydronephrosis (kidney swelling), low amniotic fluid, and lung development.

Amniotic fluid is partly made up of your baby’s urine. If they have trouble urinating, there will be less amniotic fluid. Your baby practices breathing in the womb by breathing in the amniotic fluid. This helps the lungs grow and makes them stronger.  Low fluid levels can make it harder for the lungs to develop.

Lifelong Considerations

In most cases, pyelectasis, or pelviectasis goes away on its own before a baby is born. These babies have normal urinary function and kidney health.

When the swelling does not go away on its own before delivery, further tests may be needed after birth. This is to see if there are other problems with the urinary tract.

Most children that have pyelectasis or pelviectasis when they are born will only need to be closely watched. A small number of these babies may need surgery.

For children who need surgery, kidney health will be watched over time. If the kidneys are not damaged from the swelling or blockage, most of these children have normal long-term urinary health.