Epilepsy

Early Childhood (infancy – 2 years)

Benign sleep myoclonus

These are myoclonic jerks that occur during sleep in young children, which stop if the child is woken up

– They are complete benign and not real seizures and self-limiting, so only need to provide reassurance to parents.

Infantile spasms (West’s syndrome)

This is a rare form of epilepsy in children which is usually 2nd to a serious neurological abnormality.

– it is thought to be due to malfunction of the regulation of GABA transmission

Symptoms:

– Triad of muscle spasm attacks

– Lightning attacks –> (rapid flexion of head, trunk and limbs)

– Nodding attack –> convulsions of throat and neck flexor muscles where chin jerks down and head drawn in

– Salaam/jack-knife attack –> flexor spasms which resembles the Muslim salaam greeting

– Patient also have intellectual disabilities

Diagnosis:

EEG shows hypsarrthymia, a chaotic and disorganised electrical activity with no pattern

Management:

– Hormonal therapy such as steroid or ACTH

– Can also use Vigabatrin, which inhibits GABA breakdown to increase inhibitory transmission

Mid-Childhood (2-9 years)

Lennox-Gastaut Syndrome (LGS)

This is a rare condition which gives epilepsy in children around the age of 3-5 and persists into childhood

– Around 20% of children with West’s syndrome will go on to develop LGS)

Symptoms:

– Seizures –> mostly tonic seizures which occur during non-REM sleep

– Seizures can occur daily and are difficult to treat with anticonvulsive medication

– Maybe a clinical history of West’s syndrome

– Eye problems –> 90% also have eye dysfunction e.g., refractive error, strabismus

Diagnosis;

EEG shows characteristic slow wave spike

Management:

– 1st line is sodium valproate

– Ketogenic diet –> helps to decrease frequency of seizures

Childhood Absence Epilepsy

This is an idiopathic epilepsy disorder which caused absence seizures in normally healthy children

– Children have absence seizures which are brief but can occur up to hundreds of times a day

– Can cause some automatisms, but the presence of major motor symptoms excludes the diagnosis

Symptoms:

– Multiple short (4-20s) absence seizures with quick recovery

– Apart from this they have normal development (most will become seizure free in adolescence)

– No major motor symptoms

Diagnosis:

– MRI is normal

– EEG shows characteristic 3Hz, generalised symmetrical spikes

Management:

– Sodium valproate or ethosuximide

Benign Rolandic epilepsy

This is the most common epilepsy syndrome in children, starting around 3-13 and stops about 14-18 years

– The seizures start around the central sulcus of the brain, around the Rolandic Fissure

– These children usually have normal intelligence and development, and learning can remain unimpaired

Symptoms:

Single focal seizures giving unilateral face paraesthesia when waking up

Diagnosis:

EEG shows characteristic spikes in the centro-temporal area

Management:

As so mild, treatment often unnecessary –> but 1st line is Carbamazepine for the focal seizure

Febrile Convulsions

This is a seizure associated with a fever of greater then 38 degrees Celsius in an otherwise healthy child.

– They usually occur before the age of 5 and rarer to see in older children. The key point is that they are a consequence of the acute infection and not associated with underlying neurological problems.

Symptoms:

– Brief tonic-clonic seizures lasting less than 5 minutes

– Typically, are provoked by a viral infection, so there will be signs of a concurrent illness.

Typically, febrile convulsions are divided according to their duration:

i) Simple –> last <15 minutes and will resemble a generalised seizure. They do not recur within 24 hours

ii) Complex –> they last 15-30 minutes and resemble a focal seizure

– Can have repeats within 24 hours and recovery maybe incomplete (Todd’s palsy)

iii) Status epileptics –> this is a febrile seizure which lasts >30 minutes

Diagnosis:

Based on the history, no real need to blood test, MRI, or EEG

Management:

– If it is the first seizure, or any features of a complex seizure –> admit to hospital

– If recurrences, parent should be taught how to use rectal diazepam or buccal midazolam

– For the acute seizure, management is the same.

Reflex anoxic seizures

These are seizures that occur in healthy children in response to painful or emotional stimuli.

– They are caused by neurally-mediated transient asystole in children with very sensitive vagal cardiac reflexes and are not epileptic seizures or epilepsy

Symptoms:

Child turns pale and falls to floor, followed by rapid recovery

Diagnosis:

Clinical diagnosis of exclusion

Management:

No treatment needed, and it has a very good prognosis

Late-Childhood (> 9 years)

Juvenile Myoclonic epilepsy (Janz Syndrome)

This is a common form of generalised epilepsy in teenage children aged 12-18 which is more common in girls

– Disorder typically involves infrequent generalised seizures early in the morning as it is associated with sleep deprivation

Symptoms:

– Brief episodes of involuntary muscle contractions in morning or before falling asleep

– The myoclonic jerks are more common in arms than legs (may result in dropping objects)

– These myoclonic jerks are followed by generalised tonic-clinic seizures after a few months

Diagnosis:

EEG shows characteristic 4-6Hz polyspike and slow wave discharges

Management:

1st line is Sodium Valproate, and avoid sleep deprivation