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Tuberous Sclerosis


The Manual's Editorial Staff

Last full review/revision May 2020| Content last modified May 2020
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What is tuberous sclerosis?

"Tuberous" refers to an abnormal growth shaped like a tuber, which is a root vegetable like a potato or yam. "Sclerosis" means hardening of something soft, like growths or organs.

Tuberous sclerosis is a rare genetic disorder in which many hard, tuber-shaped tumors grow in your child's brain and sometimes other organs such as the heart, kidneys, and lungs. Some of the growths are cancerous.

  • The most common symptoms include seizures (usually infantile spasms), skin growths and colored patches, and learning and behavior problems

  • Doctors suspect the disorder based on your child's symptoms and confirm it by genetic tests

  • There's no cure but medicines sometimes help relieve symptoms

  • Repeat imaging studies help identify new tumors early on, when treatment is more likely to be successful

What causes tuberous sclerosis?

Tuberous sclerosis is caused by an abnormal gene.

Sometimes, the baby inherits the abnormal gene from a parent. Other times, the baby is the first person in the family to have the abnormal gene.

What are the symptoms of tuberous sclerosis?

The symptoms vary and are more severe in some children than in others.

  • The first symptom may be seizures, particularly the type of seizures called infantile spasms

  • Often your child's skin has colored patches, flat spots, lumps, and bumps

  • Patches may form at the back of your child's eye (retina), which can affect vision

  • Often in children, the surfaces of the permanent teeth are pitted

Tumors cause symptoms that vary depending on where the tumor grows:

  • Brain tumors can cause headaches, seizures, or intellectual disabilities and can slow a child’s development

  • Kidney tumors can cause high blood pressure, stomach pain, and blood in the urine

  • Lung tumors (often in teenage girls) can cause breathing problems

  • Heart tumors form before birth and have no symptoms

How do doctors know my baby has tuberous sclerosis?

Doctors may suspect tuberous sclerosis if your baby has seizures and delayed development along with certain skin changes.

  • Your child’s doctor will do an eye exam to check for eye problems

  • The doctor will order an MRI or ultrasound (scans showing detailed pictures of the inside of your body) to check for tumors

  • A genetic test to check for the damaged gene may be done to confirm the diagnosis

Sometimes, doctors see tumors in a baby’s heart or brain during an ultrasound done before the baby is born.

How do doctors treat tuberous sclerosis?

There's no cure for tuberous sclerosis.

Doctors will recommend treating your child’s symptoms with:

  • Drugs to treat seizures or high blood pressure

  • Sometimes surgery to remove tumors

  • Sometimes a drug to shrink the tumors

  • Special schooling and physical therapy, occupational therapy, and speech and language therapy for developmental difficulties

  • Procedures to remove skin growths

How can I prevent tuberous sclerosis in my baby?

Tuberous sclerosis can't be prevented.

However, if tuberous sclerosis runs in your family and you're planning on having children, you can get genetic tests to see if you carry the gene that can causes tuberous sclerosis. Genetic counseling can help determine the risk of your child having the disorder.

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