Key Takeaways

  • A cystic hygroma is a growth commonly located on a baby’s neck.
  • A cystic hygroma occurs as a result of a blockage in the lymphatic system, which circulates fluids, fats, and white blood cells throughout the body.
  • Cystic hygromas range in size and severity. They can potentially obstruct breathing.

What is a cystic hygroma?

A cystic hygroma, otherwise known as a lymphangioma, is a birth defect that causes a large fluid-filled sac to form in the nuchal region (around the head and neck). The cyst is made of lymphatic tissues and white blood cells, and it could also potentially form in the armpit and groin area.

Cystic hygroma is different from nuchal translucency, which is a fluid-filled space behind the neck visible during ultrasounds in the first trimester. This structure is found on every baby, and its size is used to diagnose other genetic disorders.  

What causes cystic hygromas in children?

While the precise cause of cystic hygromas is unknown, doctors believe that they can be attributed to environmental and genetic factors that affect development of the lymphatic vascular system. Cystic hygromas usually form on their own, though they may also occur at the same time as other chromosomal abnormalities such as Down syndrome, Noonan syndrome, or Turner syndrome. Maternal viral infections and excessive drug/ alcohol use during pregnancy may also cause cystic hygroma. When cystic hygroma is diagnosed in adults, it is more likely that it has occurred as a result of trauma or upper respiratory infection.

Cystic hygromas are created when lymph sacs and vessels develop incorrectly in the womb. Lymph sacs start forming in the baby around the fifth week of pregnancy, where they first appear in the head, neck, chest, and arms. From there, lymphatic vessels form to serve as channels that transport fluid, fats, and white blood cells throughout the body. Blockages in this lymphatic system stop fluids from circulating properly, instead causing cells to build up and create a cyst.

What are the symptoms of cystic hygromas? 

Depending on the size of the cystic hygroma, symptoms vary. Some possible symptoms include:

  • Soft bulge under skin with blue tint
  • Growth on neck that suddenly changes in size as the child grows
  • Disfigurement around head and neck
  • Impairment of surrounding organs
  • Obstructive sleep apnea
  • Obstructed airway/ respiratory distress
  • Deformed teeth or bones
  • Webbed neck
  • Tissue swelling

If your child has any sort of cyst, you should contact your doctor immediately. Never try to puncture or drain a growth yourself. This can cause infection and severe bleeding.