About childhood epilepsy

What is epilepsy?

Epilepsy is a chronic neurological disorder characterized by recurrent epileptic seizures.
These seizures are caused by sudden, abnormal electrical activity in the brain. Beyond the seizures themselves, epilepsy significantly affects a patient’s cognitive, psychological, and social functioning.

In children, epilepsy can therefore impact learning, development, and behavior. In Flanders, it is estimated that at least 15,000 children live with epilepsy.

Short Circuit in the Brain

To understand what epilepsy is, we need insight into how our brain works. Everything we do and think is controlled by billions of brain cells, or neurons. Our brain consists of gray matter (the cerebral cortex) and white matter (axons and dendrites). The gray matter contains the cell bodies of neurons that process different types of information. The white matter consists of the extensions of these neurons, forming nerve pathways responsible for transmitting information.

Neurons are essentially electrical cells: to send messages to other cells and organs, electrical discharges occur and chemical substances are released. For example, when you want to move your leg, the signal from the brain is transmitted to the appropriate muscles in the leg.

During an epileptic seizure, we speak of a “short circuit”: a sudden abnormal discharge occurs in a group of neurons in the brain, causing an unwanted effect in the person^1,2. This can happen in a relatively small area of the cortex—called focal seizures—or involve both hemispheres, which are then called generalized seizures. An epileptic seizure causes a temporary change in perception, behavior, or consciousness, over which we have no control. How this manifests depends on where the abnormal discharges originate in the brain.

There are different types of seizures: a person may stiffen, experience hand cramps, smell a strange odor, or briefly lose awareness, among others. Some patients have only one type of seizure, while others may experience two or more types.

We only speak of epilepsy as a disease when someone has recurrent, unprovoked epileptic seizures. A seizure can also be triggered by other causes, such as brain trauma, withdrawal from alcohol and/or drugs, fever, or medication. Epilepsy is also diagnosed when doctors determine that the patient has a high risk of recurrent seizures or when an epileptic syndrome is diagnosed after a first seizure².

In about two-thirds of children with epilepsy, seizures can be well controlled with medication. Unfortunately, in about one-third of cases, seizures persist despite treatment—this is called therapy-resistant or refractory epilepsy³. For these patients, other therapeutic options are available.

Types of seizures

Recognizing and distinguishing the type of seizure is crucial for selecting the appropriate anti-epileptic medication.

Seizure classification has evolved over the years to integrate new knowledge and meet the requirements of different clinical settings. The current classification, introduced in April 2025, includes three main types of seizures: generalized seizures, focal seizures, and unknown onset seizures⁴.

Generalized seizures

Generalized seizures begin across both hemispheres of the brain. By definition, all generalized seizures involve impaired consciousness, meaning the patient does not remember what happened during the seizure.

There are several types of generalized seizures:

Typical absence seizure: A sudden, brief loss of consciousness, usually lasting less than 30 seconds. These seizures can occur multiple times a day and may be accompanied by slight movements of the eyes or hands.
Myoclonic seizure: A brief, sudden contraction of nearly all muscles.
Tonic seizure: A sudden stiffening of the muscles, accompanied by loss of consciousness.
Clonic (rhythmic myoclonic) seizure: Repeated, rhythmic jerking of muscles in the arms and legs.
Generalized tonic-clonic seizure: A sudden loss of consciousness with stiffening of all muscles (including respiratory and jaw muscles), followed by jerking movements. There may also be urinary incontinence and foaming at the mouth, though this is not always the case.
Atonic seizure: A sudden loss of muscle tone, causing the person to collapse if standing.

Focal seizures

A focal seizure begins in one specific area of the brain. With this type of seizure, loss of consciousness does not always occur. Sometimes the patient remains aware and alert, while in other cases there may be a decrease or loss of awareness or consciousness.

There are three types of focal seizures:

Focal seizure with intact awareness
Focal seizure with impaired awareness
Focal to bilateral tonic-clonic seizure

Focal Seizure with Intact Awareness

In this type of seizure, the patient remains conscious and is aware that a seizure is occurring. Symptoms can vary depending on the part of the brain where the seizure starts:

Motor seizures: sudden jerking or twitching of muscles
Sensory seizures: sudden sensations, such as tingling, flashes of light or colors, hearing sounds, smelling odors, or tasting flavors
Autonomic seizures: physical reactions such as paleness or flushing, sweating, goosebumps, heart palpitations, etc.
Emotional seizures: feelings such as fear, a strange sensation, altered sense of time, or déjà vu

In babies, toddlers, and children with language difficulties, these seizures are often hard to recognize. They usually manifest through changes in behavior or in the way the child looks.

Focal Seizure with Impaired Awareness

In this type of seizure, there is a decrease or loss of awareness or consciousness. A focal seizure with intact awareness can evolve into a focal seizure with impaired awareness. These seizures can manifest in different ways, depending on the affected area of the brain. Possible symptoms include:

No response when spoken to
No reaction to painful stimuli
Failure to recognize people
Unconscious automatic movements (e.g., rubbing hands, fiddling, wandering)
A vacant stare
Unusual facial movements (grimacing, lip smacking, swallowing)
Repeating the same action or words
Shouting
Pedaling movements with both legs
An arm that stiffens

Focal to Bilateral Tonic-Clonic Seizure

These seizures start as a focal seizure with intact or impaired awareness. However, the localized “short circuit” in the brain spreads to bilateral, widespread networks. During a focal to bilateral tonic-clonic seizure, the patient becomes unconscious and experiences jerking movements. This type of seizure is also known as a “grand mal” or major seizure. It is the type most commonly recognized as epilepsy.

Unknown Onset (Focal or Generalized)

Epileptic seizures with unknown onset are classified as seizures where insufficient clinical or EEG information is available to determine whether they originate from a focal or generalized source.

Triggering Factors

To confirm an epilepsy diagnosis, seizures must be recurrent and not acutely provoked. However, in patients with epilepsy, various factors can contribute to more frequent seizures. For example, some children experience more seizures during periods of stress, such as illness, fever, exams, or lack of sleep. Other factors, such as excessive alcohol consumption and the menstrual cycle, can also play a role⁵.

In addition, certain stimuli—such as heat, flashing lights, sounds with specific frequencies, or other sensory triggers—can provoke seizures in some patients. This form of epilepsy is called reflex epilepsy⁵.

It is important to understand that these triggering factors are not the cause of epilepsy but merely triggers for seizures. Identifying individual triggers in a child is essential for therapy.

Therefore, we recommend a healthy lifestyle for all children with epilepsy, including sufficient sleep, proper management of fever, and a regular daily routine. Only when photosensitive epilepsy is confirmed do we discuss specific guidelines for television viewing and video games with the child and their parents.

Causes

The clinical team’s task is to classify the type of seizures as accurately as possible and to search for a potential underlying cause of epilepsy⁶. This stage of diagnosis is crucial because it determines the optimal treatment and provides important information about the prognosis.

Congenital or acquired brain disorders, as well as genetic and polygenic abnormalities, can play a role in the development of epilepsy—and sometimes these factors are interconnected. The causes of epilepsy can be summarized into several groups⁶:

Genetic/Polygenic: This cause is related to a defect in one or more genes, where seizures are often just one of several disease manifestations. It is important to note that “genetic” does not always mean inherited from parents. Sometimes a change in genetic material occurs only after conception, meaning the parents do not carry the mutation. Almost daily, new genes linked to epilepsy are being discovered.
Structural: This cause involves an abnormality or damage in the brain, which can be congenital or acquired later, for example, due to a brain tumor, head trauma, or oxygen deprivation at birth. These lesions are usually visible on a brain scan (MRI).
Infectious: Globally, epilepsy most often occurs as a result of infection, though this is not the case in Belgium and Western Europe. Seizures may result from infections caused by certain viruses, bacteria, parasites, or fungi. Well-known examples include tuberculosis, HIV, cerebral malaria, infection with the pork tapeworm, and congenital infections such as Zika virus and cytomegalovirus.
Metabolic defects: In some patients with a metabolic disorder, seizures occur as a direct consequence of the condition.
Immunological: This type of epilepsy is the direct result of a defect in the immune system, where seizures are a core symptom. In these immune disorders, cells that normally protect the body against infections mistakenly attack the brain as if it were a harmful microorganism or foreign substance.
Unknown: Sometimes the cause of epilepsy in a patient is not yet known. When new information becomes available from tests or clinical development, the physician can reassess whether the cause can be classified.

Investigating the cause is sometimes straightforward, but for some patients, it can take years.

References

1. Fisher RS, Boas WVE, Blume W, et al. Epileptic Seizures and Epilepsy: Definitions Proposed by the International League Against Epilepsy (ILAE) and the International Bureau for Epilepsy (IBE). Epilepsia. 2005;46(4):470-472. doi:10.1111/j.0013-9580.2005.66104.x

2. Fisher RS, Acevedo C, Arzimanoglou A, et al. ILAE Official Report: A practical clinical definition of epilepsy. Epilepsia. 2014;55(4):475-482. doi:10.1111/epi.12550

3. Kwan P, Arzimanoglou A, Berg AT, et al. Definition of drug resistant epilepsy: Consensus proposal by the ad hoc Task Force of the ILAE Commission on Therapeutic Strategies. Epilepsia. 2010;51(6):1069-1077. doi:10.1111/j.1528-1167.2009.02397.x

4. Beniczky S, Trinka E, Wirrell E, et al. Updated classification of epileptic seizures: Position paper of the International League Against Epilepsy. Epilepsia. Published online April 23, 2025:epi.18338. doi:10.1111/epi.18338

5. Kasteleijn‐Nolst Trenité DGA. Provoked and reflex seizures: Surprising or common? Epilepsia. 2012;53(s4):105-113. doi:10.1111/j.1528-1167.2012.03620.x

6. Scheffer IE, Berkovic S, Capovilla G, et al. ILAE classification of the epilepsies: Position paper of the ILAE Commission for Classification and Terminology. Epilepsia. 2017;58(4):512-521. doi:10.1111/epi.13709