Tuberous Sclerosis and epilepsy

Tuberous Sclerosis Complex (TSC) is a rare genetic disorder that affects multiple organ systems and causes tumours to develop in different parts of the body. These tumours are mostly benign (non-cancerous), and commonly affect the brain, heart, kidneys, eyes, lungs and skin. TSC affects 1 in every 6,000 people and can present at any age. 

How does epilepsy affect people with TSC? 

The vast majority of people who develop TSC will also develop epilepsy. Over 90% of those with TSC will also be diagnosed with epilepsy, which may even progress to the point where they are intractable to medication. This means finding effective treatment can be difficult. 

The reason for this commonality is most likely tumours within the brain, which is a cause of many types of epilepsy. These could be:

• Cortical tubers, which are regions of the brain with abnormal development
• Giant cell astrocytoma, which are lesions that can block the flow of spinal fluid
• Subependymal nodules, which is small regions of abnormal brain tissue found in the ventricles

What type of seizures do people with TSC normally have? 

People with TSC who also develop epilepsy can have varied seizures: 

Infantile spasms are one of the most typical and can be often seen in the first year of life. Infantile spasms last just seconds at a time and can be characterised by sudden flexions of the arms and legs. These flexions will often occur multiple times over a matter of minutes in clusters and are most common as the infant is going to sleep or waking up. 

Focal (partial) seizures are also a common seizure type for those with TSC. These are characterised by rhythmic jerking, as well as eye and head deviations. In more extreme cases, these can evolve to a tonic-clonic seizure. 

Tonic and atonic seizures may also arise as a result of TSC. Tonic seizures result in a stiffening of the body, arms and legs. An atonic seizure is in many ways the opposite of a tonic seizure, whereby the body, arms and legs will go limp and the person will fall forwards to the floor, hence why they are less formally called “drop attacks”.

Myoclonic and absence seizures may also occur in people who have TSC. Myoclonic seizures result in brief jerks of the extremities and/or the head that may cause the person to fall, whereas absence seizures are characterised by brief periods of unconsciousness.  

Get more detailed descriptions of each of the seizure types here in an earlier blog post. 

What types of epilepsy treatment are available to those with TSC? 

As previously mentioned, many people with TSC will progress to become intractable, which means that anti-epileptic medications (AEDs) may become less effective over time. However, until this happens a number of AEDs can be effective at helping to manage seizures and limit their frequency. 

Should the person become intractable there are other treatment options. The ketogenic diet, for example, could prove effective. As could epilepsy surgery or vagus nerve stimulation. 

National Epilepsy Training can help

For more information and advice on TSC and epilepsy, please call us on 01706 373075 or email admin@nationalepilepsytraining.co.uk.