Neurological disease in a child: Epilepsy

Question 1

Define epilepsy.

Answer 1

Two or more seizures unprovoked by an immediately identifiable cause.

Question 2

How does the International League Against Epilepsy (ILAE) classify seizures?

Answer 2

By localisation (in which part of the brain the epileptic activity starts) and aetiology.

Question 3

What are the different classifications for seizures?

Answer 3

Generalised: Large part of cortex is involved, consciousness in impaired

Localised (focal, local, partial): Begins in a focal area of the cerebral cortex

Symptomatic epilepsy: Cause is known

Cryptogenic epilepsy: Presumed to be symptomatic but the etiology is not known

Idiopathic epilepsy: No apparent cause

Question 4

Explain the pathophysiology of epilepsy.

Answer 4

Imbalance between excitatory and inhibitory neurotransmission resulting in high-frequency burst activity seen as spike and wave on EEG. Seizure propagates if sufficient surrounding neurons are recruited.

Question 5

What are risk factors and associations with epilepsy?

Answer 5

Idiopathic: Many have positive family history

Symptomatic: Head trauma, encephalitis, meningitis, CNS tumours, hypoxic-ischaemic injury, intrauterine infections, cerebral dysgenesis and specific aetiologies

Associations: Non-epileptiform attack disorder (also known as pseudo-seizures)

Question 6

Summarise the epidemiology of epilepsy.

Answer 6

1% of children suffer from epilepsy

Question 7

What are the symptoms of an absence seizure?

Answer 7

Onset 4-12 years.

Short episodes (<20 seconds) during which the child stares or blinks, with no apparent awareness of the surrounding.

No aura of postictal phase. May present as ‘day dreaming’ in class and reduced performance in school. Usually undergo spontaneous remission during adolescence.

Question 8

What are the symptoms of a myoclonic seizure?

Answer 8

Sudden brief muscle contractions; often cluster within a few minutes.

If they evolve into rhythmic jerking movements, they are classified as a clonic seizure.

Question 9

What are the symptoms of an atonic seizure?

Answer 9

Consist of brief loss of postural tone, often resulting in falls and injuries. This seizure type occurs in people with significant neurological abnormalities.

Question 10

What are the symptoms of a clonic seizure?

Answer 10

Rhythmic, jerking movements

Question 11

What are the symptoms of a tonic seizure?

Answer 11

Sudden-onset tonic extension or flexion of the head, trunk and/or extremities for several seconds.

Question 12

What are the symptoms of a generalised tonic-clonic seizure?

Answer 12

Tonic extension lasting for a few seconds followed by clonic rhythmic movements and a prolonged postictal phase.

Often associated with tongue biting, urinary or faecal incontinence.

Question 13

What are the symptoms of status epilepticus?

Answer 13

A generalised convulsion lasting > 30 minutes or repeated convulsions occurring over 30 minutes without recovery of consciousness between each convulsion.

Question 14

What are the symptoms of a simple partial seizure?

Answer 14

Seizure with preservation of consciousness; includes sensory, motor, autonomic and psychic experiences. Tonic or clonic movements are initially localised but may move to different parts of the body if the seizure is propagated.

Question 15

What are the symptoms of a complex partial seizure?

Answer 15

Similar to simple partial seizure but consciousness is impaired and the episode is followed by postictal phase.

Question 16

What are symptoms of a partial seizure with secondary generalisation?

Answer 16

Focal seizure is followed by GTCS.

Question 17

What are symptoms of Lennox-Gastaut syndrome?

Answer 17

Affects children aged 1-3 years. Characterised by multiple seizure types (tonix-axial, atonic and absence seizures), developmental regression and learning disability. Often chronic epilepsy resistant to therapy.

Question 18

What are symptoms of benign childhood epilepsy with centrotemporal spike?

Answer 18

Affects children aged 4-10 years. Clonic seizures affecting face and upper limbs usually during sleep; may progress to GTCS. Also known as benign Rolandic epilepsy. Usually undergo spontaneous remission during adolescence.

Question 19

What are symptoms of juvenile myoclonic epilepsy?

Answer 19

Affects adolescents; idiopathic generalised epileptic syndrome characterised by myoclonic jerks, GTCS and sometimes absence seizures, usually on awakening. Usually require lifelong treatment but not associated with intellectual impairment.

Question 20

What are appropriate investigations for epilepsy?

Answer 20

General and neurological examination must be performed to rule out specific aetiologies and focal neurological signs.

EEG: Epileptiform spike and wave activity correlates with different forms of epilepsy (hypsarrhythmia in infantile spasms)

MRI: To rule out underlying pathology, e.g. glial tumour

Lumbar puncture: If infective cause suspected ECG/ECHO/lying/standing

BP: To exclude other causes of fit, faints and funny turns

Question 21

What is the management for epilepsy?

Answer 21

Education: Explain nature of epilepsy to parent and child. Aim is to give child the most confidence and independence possible. Avoid precipitating factors such as alcohol, sleep deprivation, drugs. Supervision when in swimming pools or baths. Information on driving and insurance. Advice on sudden unexpected death in epilepsy (SUDEP). Side effects of AED (e.g. teratogenicity of sodium valproate).

Follow-up: All children with epilepsy should have structured review at least yearly.

Acute treatment of seizure: Long-term antiepileptic medication

Question 22

What anti-epileptic medication can be used for generalised epilepsy?

Answer 22

Absence seizures: Sodium valproate, lamotrigine, ethosuximide, topiramate. Exacerbated by carbamazepine.

Myoclonic: Sodium valproate, lamotrigine, topiramate, levetiracetam (adjunct).

Tonic-clonic: Sodium valproate (first-line), topiramate, lamotrigine, levetiracetam (adjunct).

Question 23

What anti-epileptic medication can be used for partial epilepsy?

Answer 23

Carbamazepine (first-line), topiramate, lamotrigine, gabapentin.

Question 24

What anti-epileptic medication can be used for epilepsy syndromes?

Answer 24

Infantile spasms: ACTH, prednisolone, vigabatrin.

Lennox–Gastaut syndrome: Lamotrigine, topiramate, vigabatrin.

Benign childhood epilepsy with centrotemporal spike: Carbamazepine (problematic or daytime seizures only).

Juvenile myoclonic epilepsy: Sodium valproate.

Question 25

When may the ketogenic diet be considered for children with epilepsy?

Answer 25

Children with drug-resistant epilepsy

Question 26

What are complications associated with epilepsy?

Answer 26

Developmental delay

Poor school performance

SUDEP (500 deaths/year)

Question 27

What is the prognosis of epilepsy?

Answer 27

Remission depends predominantly on the type of epilepsy.

Patients with epilepsy have a mortality rate 2–3 x that of the general population.