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Patient Story

A 2-year-old girl was brought to her pediatrician for her well child visit. On exam, she was noted to have several hypomelanotic lesions over her trunk (Figures 205-1 to 205-3). Based on the presence of these lesions, the pediatrician orders an MRI of the brain, which revealed subependymal tubers, which also projected into the ventricles. She was diagnosed with Tuberous sclerosis, and a renal ultrasound and cardiac echocardiogram were obtained, which did not reveal any abnormalities. A multidisciplinary approach to her care was planned and included a pediatric neurologist, developmental pediatrician, and dermatologist.

FIGURE 205-1

Hypomelanotic, or “ash leaf” lesion on the abdomen of a 2-year-old girl found to have tuberous sclerosis. She presented with over five hypomelanotic lesions on exam. This prompted the physician to order an MRI of the brain. Tubers were found to confirm the diagnosis. (Used with permission from Richard P. Usatine, MD.)

FIGURE 205-2

Hypomelanotic, or “ash leaf” lesion on the back of the same child as in Figure 205-1. (Used with permission from Richard P. Usatine, MD.)

FIGURE 205-3

Hypomelanotic or “ash leaf” lesion in axilla of the child in Figure 205-1. (Used with permission from Richard P. Usatine, MD.)


Tuberous sclerosis (also called Tuberous sclerosis complex-TSC) is an inherited neurocutaneous and multisystemic disorder characterized by hamartomas (sclerotic tubers), which most notably affect the skin, brain, kidneys, heart and eyes.1,2 TSC results in a wide spectrum of clinical manifestations and neurologic sequelae.


  • Bourneviller Pringle Syndrome, Epiloia, Phakomatosis TS, Tuberose sclerosis, Tuberous Sclerosis-1, and Tuberous Sclerosis Complex (TSC).


  • TSC affects both sexes equally and all ethnic groups.

  • The prevalence is estimated to be one per 6,000 to 10,000 individuals.3

  • With one affected parent, the recurrence risk is 50 percent. When both parents appear to be unaffected, the recurrence risk is 1 in 22 after one affected offspring and 1 in 3 after two affected offspring.

  • Only 7 to 37 percent of newly diagnosed cases have a family history of TSC.

Etiology and Pathophysiology

  • TSC is caused by mutations on two genes, named TSC1 and TSC2. Only one of the genes needs to be affected for TSC to be present.

  • TSC has an autosomal dominant mode of inheritance with almost complete penetrance, but a variable expressivity range in terms of the age of onset, severity of disease, and different signs and symptoms that result from a specific genotype.

  • The variability is due to multiple causes. These include somatic ...

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