Health Library

What Is Chylous Ascites?

Chylous ascites is when chyle collects in the belly. Chyle is a milky fluid made in the bowels (intestines) during digestion.

Depending the cause, doctors can treat chylous ascites (KYE-lus uh-SYE-teez) and often cure it.

What Happens in Chylous Ascites?

Chyle (KYE-ul) is made of lymph and tiny fat droplets. Lymph (LIMF) is a clear fluid that carries fats and proteins, helps fight germs, and keeps the body’s fluid levels normal.

Lymph vessels take chyle to the bloodstream. From there, the blood carries lymph and fats where they are needed.

When the lymphatic system is damaged or isn’t working as it should, this normal flow can’t happen. The chyle can’t get into the blood, and instead leaks into other places. In chylous ascites, it leaks into the belly.

What Are the Signs & Symptoms of Chylous Ascites?

While there’s only a little fluid in the belly, chylous ascites may not cause any symptoms. But as the fluid builds up, it can cause:

• a large, rounded belly
• a swelling or bulge at the belly button (umbilical hernia)
• loss of appetite
• one or more lumps in the groin (from a hernia or swollen lymph nodes)
• swelling of the genitals or legs
• trouble breathing
• vomiting

Kids with chylous ascites also can have trouble fighting infections and may get blood clots.

What Causes Chylous Ascites?

Children with the condition usually have it because of:

• a problem in the lymphatic system that the child is born with
• trauma that injures the lymphatic vessels

Less often, a child may get it after belly surgery, from cancer, or from other medical problems.

How Is Chylous Ascites Diagnosed?

Before a baby is born, doctors might suspect chylous ascites when a routine prenatal ultrasound shows fluid in the baby’s belly. They’ll do more tests to be sure.

In infants and children, doctors test the fluid in the belly. They use a needle to take a sample and send it to a lab for testing. If the fluid has chyle, they’ll do other tests to find out how it’s getting into the belly, such as an X-ray, ultrasound, CT scan, or MRI.

If they need more information, doctors can do minimally invasive surgery (laparoscopy). They make small cuts in the belly and use a tiny camera and instruments to look for problems.

How Is Chylous Ascites Treated?

If a fetus has chylous ascites, doctors will watch the mother’s pregnancy closely. When she gives birth, they’ll care for the baby in the NICU.

Treating the condition depends on what’s causing it. Chylous ascites caused by a leak in the lymphatic system may heal on its own.

Treatment, if needed, may include:

• removing fluid from the belly with a needle
• placing a drain in the belly so the fluid can flow out
• helping the body make less chyle with medicine, a low-fat diet, or IV nutrition (total parenteral nutrition, or TPN)
• interventional radiology to fix the lymph vessel

How Can Parents Help?

If your child has chylous ascites, be sure to:

• Take your child to all doctor’s visits.
• Make sure your child takes any prescribed medicines.
• Help your child with any prescribed diet changes.