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Early diagnosis and monitoring can make all the difference for patients living with TSC-associated seizures

Epilepsy impacts most patients living with TSC, and may often have devastating consequences1-4

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Epilepsy affects 70% to 90%

of patients living with TSC. After just one seizure, patients living with TSC have a nearly 100% chance of developing recurring seizures.1-3

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A greater likelihood of developmental disabilities

is correlated with epileptic spasms, a history of seizures, greater seizure frequency, earlier seizure onset, and pharmacoresistant epilepsy.3,5

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Approximately 90% of patients living with TSC

are affected by TSC-associated neuropsychiatric disorders (TAND), which may include behavioral difficulties, psychiatric disorders, and variations in intellectual ability.6,7

With multiple neurological and clinically observable symptoms, a diagnosis of TSC can start in your office.8

Patients living with TSC-associated seizures may present with numerous neurological signs and symptoms, including multiple seizure types that vary over time.9,10 Guidelines recommend that parents should be educated to recognize TSC-associated seizures, which can be highly variable.3,9,11-13

Initial events may often begin as subtle EEG changes or seizures, which may easily be overlooked by parents2,14

  • Partial-onset seizures,* also known as focal seizures, are likely to be encountered in over 2/3 of patients during infancy9
  • Partial-onset seizures can be seen with or without impairment of awareness or can progress to generalized seizures15
  • Infantile spasms may occur in 39% to 47% of patients9

*Partial-onset seizures (focal) included simple partial seizures (focal motor seizure), complex partial seizures (focal impaired), and secondary generalized tonic-clonic seizures (focal to bilateral tonic-clonic).16

Patients will likely progress to more than one seizure type, including9,10:

  • Partial-onset seizures
  • Atonic
  • Tonic
  • Clonic
  • Tonic-clonic
  • Despite an often early presentation, it is not uncommon for patients to receive a diagnosis of TSC in adolescence or adulthood3,11
  • 12% of patients living with TSC may develop seizures in adulthood3,5

Experts recommend obtaining a baseline EEG and monitoring in all patients living with a TSC diagnosis, even in the absence of recognized or reported clinical seizures.13,17

Kierstin is a 15 year old EPIDIOLEX patient living with TSC

Kierstin, at age 15 | EPIDIOLEX patient living with TSC

Diagnosing TSC is achievable through several observable clinical features8

A definite diagnosis of TSC requires 2 major features or 1 major feature with 2 minor features.
A possible diagnosis of TSC may be made with either 1 major feature or ≥2 minor features.


Central nervous system

  • Multiple cortical tubers and/or radial migration lines
  • Subependymal nodules (SEN) (≥2)
  • Subependymal giant cell astrocytomas (SEGA)


  • Multiple retinal hamartomas


  • Angiomyolipomas (≥2)


  • Hypomelanotic macules (≥3, at least 5 mm in diameter)
  • Angiofibromas (≥3) or fibrous cephalic plaque
  • Ungual fibromas (≥2)
  • Shagreen patch


  • Cardiac rhabdomyoma


  • Lymphangioleiomyomatosis (LAM)


Skin and teeth

  • Confetti skin lesions
  • Dental enamel pits (≥3)
  • Intraoral fibromas (≥2)


  • Retinal achromic patch


  • Multiple renal cysts


  • Nonrenal hamartomas


  • Sclerotic bone lesions

A combination of the LAM and angiomyolipomas without other features does not meet criteria for a definite diagnosis.

Consider confirming a TSC diagnosis through genetic testing identifying a TSC1 or TSC2 pathogenic mutation.8

Treatment considerations for TSC-associated seizures

Despite trial of multiple ASMs, many patients living with TSC may continue to experience multiple seizure types that vary over time9,18

64% of patients

will eventually initiate 3 or more ASMs in search of seizure reductions—and 35% try 5 or more for their TSC-associated epilepsy.18

More than 1 in 3 patients

who have surgery for their epilepsy will undergo multiple procedures.18

For 38% of patients

in a large TSC study, partial-onset seizures remained uncontrolled.9

The information provided is not intended to supersede independent clinical judgment or institutional protocols.