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Tuberous Sclerosis Complex

By

M. Cristina Victorio

, MD, Akron Children's Hospital

Reviewed/Revised Sep 2021 | Modified Sep 2022
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Tuberous sclerosis complex is a hereditary disorder that causes abnormal growths in the brain, changes in the skin, and sometimes tumors in vital organs, such as the heart, kidneys, and lungs.

  • Tuberous sclerosis complex is caused by mutations in a gene.

  • Children may have abnormal skin growths, seizures, delayed development, learning disorders, or behavioral problems and may be intellectually impaired or autistic.

  • Life expectancy is usually unaffected.

  • Because the disorder is lifelong and new problems can develop, people must be monitored for their entire life.

  • The diagnosis is based on established criteria, symptoms, imaging tests, and sometimes genetic tests.

  • Treatment is focused on relieving symptoms.

Tuberous sclerosis complex is a neurocutaneous syndrome. A neurocutaneous syndrome causes problems that affect the brain, spine, and nerves (neuro) and the skin (cutaneous).

In tuberous sclerosis complex, tumors or other abnormal growths develop in several organs, such as the brain, heart, lungs, kidneys, eyes, and skin. The tumors are usually noncancerous (benign). The disorder is named for the typical long and narrow tumors in the brain, which resemble roots or tubers.

Tuberous sclerosis complex is usually present at birth, but symptoms may be subtle or take time to develop, making the disorder difficult to recognize early.

In most cases, the disorder results from mutations in one of two genes. If either parent has the disorder, children have a 50% chance of having it. However, tuberous sclerosis complex often results from spontaneous—new (not inherited)—mutations in the gene, rather than an inherited abnormal gene. This disorder occurs in 1 in 6,000 children.

Symptoms of Tuberous Sclerosis Complex

Symptoms of tuberous sclerosis complex vary greatly in severity.

The skin is often affected, sometimes causing disfigurement:

  • Light-colored, ash-leaf–shaped patches may appear on the skin during infancy or early childhood.

  • Rough, raised patches resembling orange peel (shagreen patches), usually on the back, may be present at birth or develop later.

  • Medium-brown, flat spots that are the color of coffee with milk (café-au-lait spots) may also develop.

  • Red lumps consisting of blood vessels and fibrous tissue (angiofibromas) may appear on the face later during childhood (called adenoma sebaceum).

  • Small fleshy bumps (fibromas) may grow around and under the toenails and fingernails (Koenen tumors) at any time during childhood or early adulthood.

Examples of Skin Problems in Tuberous Sclerosis Complex

Before birth, benign heart tumors called rhabdomyomas may develop. Sometimes these tumors cause heart failure in newborns. These tumors typically disappear over time and do not cause symptoms later in childhood or in adulthood.

In many children, permanent teeth are pitted.

Patches and benign tumors may develop on the retina, located at the back of the eye. If the patches or tumors are located near the center of the retina, vision may be affected.

Tubers in the brain may become tumors, which sometimes become cancerous, and enlarge, causing headaches or making other symptoms worse.

Diagnosis of Tuberous Sclerosis Complex

  • Established criteria

  • A doctor's evaluation

  • Magnetic resonance imaging or ultrasonography

  • Sometimes genetic testing

Doctors can use an established set of criteria to help them diagnose tuberous sclerosis complex (for more information, see diagnosis of tuberous sclerosis). Before they apply the criteria, doctors first do a physical examination to determine whether people have certain symptoms, such as seizures, delayed development, or typical skin changes.

Genetic testing may be done for the following reasons:

  • To confirm the diagnosis when symptoms suggest it

  • To determine whether people who have a family history of the disorder but who do not have symptoms have the abnormal gene

  • To check for the disorder before birth (prenatal diagnosis) if the family history includes the disorder

Prognosis for Tuberous Sclerosis Complex

How well affected people do depends on how severe the symptoms are. If symptoms are mild, infants generally do well and grow up to live long, productive lives. If symptoms are severe, infants may have serious disabilities.

Nonetheless, most children continue to develop, and life expectancy is usually unaffected.

Treatment of Tuberous Sclerosis Complex

  • Treatment of symptoms and complications

  • Sirolimus or everolimus

Treatment of tuberous sclerosis complex is focused on relieving symptoms:

Sirolimus and everolimus are being studied to determine whether they can effectively treat or prevent some of the complications of tuberous sclerosis complex. In some people, these drugs taken by mouth have been shown to shrink brain and heart tumors and facial growths and to lessen seizures. Sirolimus applied to the skin may be helpful for skin growths on the face. These drugs are currently used to treat certain cancers and to prevent rejection of transplanted organs.

Genetic counseling is recommended for affected people and family members when they are considering having children.

Screening for new problems

Because tuberous sclerosis complex is a lifelong disorder and new problems can develop, affected people must be closely monitored for the rest of their life.

Monitoring typically includes the following:

  • MRI of the head

  • Ultrasonography or MRI of the abdomen to check for kidney tumors

  • Periodic computed tomography (CT) scan of the chest for women age 18 and older

  • Echocardiography (scan of the heart using ultrasound)

  • Detailed testing of mental function (neuropsychologic testing) for children to help plan for support at school and behavior management

Drugs Mentioned In This Article

Generic Name Select Brand Names
HYFTOR, Rapamune
Afinitor , Afinitor DISPERZ, Zortress
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