Tuberous Sclerosis

Experts divide the signs and symptoms into two categories: major and minor features. A confirmed diagnosis of TSC requires two or more major features. Because symptoms may appear over time, a healthcare provider can classify your diagnosis as “possible TSC” if you have only one major feature or at least two minor features.

Major features

• At least three ash leaf spots, each at least 5 millimeters (mm) at their widest point.
• At least two facial fibromas or a fibroma plaque on your face or head.
• At least one fingernail or toenail fibroma.
• At least one Shagreen patch.
• More than one growth on your retinas.
• Certain types of tissue growth in or on your brain.
• A certain type of growth in your heart.
• Certain types of benign tumors affecting your lungs, kidneys or lymph nodes.

Minor features

• Confetti skin lesion.
• Four or more pits in the enamel on your teeth.
• Two or more growths in your mouth.
• Growths on your retinas.
• More than one cyst in your kidneys.
• Benign growths in other organs or areas.

What tests will be done to diagnose tuberous sclerosis?

Because TSC can cause so many different symptoms and effects, there are many possible tests. The tests often vary depending on your symptoms. Because so many factors can affect the tests you’ll undergo, your healthcare provider is the best person to tell you what tests they recommend and why. Some common tests for tuberous sclerosis are listed below. Genetic testing ultimately confirms the diagnosis of TSC and helps identify the specific mutation in the TSC genes.

Tests for brain-related symptoms

Diagnostic imaging and other forms of testing are most likely for brain-related symptoms. This is especially true if you have seizures (or any evidence that suggests you could have seizures). Imaging scans and tests that are possible include:

• Computed tomography (CT) scan.
• Magnetic resonance imaging (MRI scan).
• Electroencephalogram (EEG).

If a provider suspects an intellectual disability, they might recommend undergoing certain types of cognitive tests. These tests help identify problems with how your brain and thinking processes work. They usually include questions or tasks related to memory, judgment and decision-making.

Tests for skin-related symptoms

A physical examination is a key part of identifying TSC. Many of the signs and symptoms of this condition are visible at an early age. A healthcare provider can use certain tests to help them confirm or rule out TSC. The most likely tests include:

• Wood’s lamp examination (a noninvasive test that uses ultraviolet light to make ash leaf spots glow).
• Skin biopsy.

Tests for changes elsewhere inside your body

Genetic testing is a key tool that can help detect TSC. Between 75% and 95% of cases will have a TSC1 or TSC2 mutation. You can still have it without a detectable mutation, but this is less common.

Many changes with TSC start when a person is still a fetus developing in the uterus. Healthcare providers can sometimes detect those changes during routine prenatal care, especially ultrasound tests, or with CT or MRI scans soon after birth.