Epilepsy

Question 1

Describe an epileptic seizure

Answer 1

-Discrete episode of symptoms
-Reflecting brain disturbance
-Due to paroxysmal abnormal electrical activity (often presumed)

Question 2

Describe epilepsy as a condition

Answer 2

-A continuing tendency to unprovoked (can have a event as trigger) epileptic seizures

Question 3

Conditions associated with epilepsy

Answer 3

-cerebral palsy: around 30% have epilepsy
-tuberous sclerosis
-mitochondrial diseases

Question 4

Classification of epileptic seizures

Answer 4

1. Where seizures begin in the brain
2. Level of awareness during a seizure (important as can affect safety during seizure)
3. Other features of seizures

-Focal onset
=Features reflect site of origin, look for underlying focal cause
=Awareness: affected or not?
=Motor onset or other?

-Generalised onset
=Reflect generalised disorder e.g. genetics
=Motor: GTCS, GTS, GCS, other (myoclonic)
=Absences

Question 5

Classification of epilepsy

Answer 5

-Primary
= Not a symptoms of underlying disease
=Generally genetic

-Secondary
= Due to some other disease (trauma, infection, tumour, stroke)

Question 6

Describe auras

Answer 6

-Precede a seizure
-Due to focal epileptic disturbance which then spreads to become generalised
=Aura itself a seizure so a focal cause

Question 7

Examples of epilepsy classification

Answer 7

Primary:
=Primary absence seizure disorder of childhood
=Juvenile Myoclonic Epilepsy

Secondary:
=Focal motor epilepsy with secondary generalisation due to glioma
=Temporal lobe seizures due to mesial temporal lobe sclerosis

Question 8

Presentation of epilepsy

Answer 8

As well as the seizure activity described above patients who have had generalised seizures may
bite their tongue
experience incontinence of urine

Asking about such features can be useful way of detecting epileptic seizures when taking a history from a patient who presents with a ‘blackout’ or ‘collapse’.

Following a seizure patients typically have a postictal phase where they feel drowsy and tired for around 15 minutes.

Question 9

Questions for diagnostic steps

Answer 9

-Episode(s) epileptic seizure(s) or not?
-If so, what types of seizures ?
-Is there a continuing tendency to unprovoked seizures ?
-Primary or Secondary ?
-If Primary: what is the Epilepsy Classification ?
-If Secondary: what is the Epilepsy classification & cause ?

Question 10

Investigations for epilepsy

Answer 10

-Brain imaging (cause)
-Routine EEG (classification- where seizure began, level of awareness during seizure, other features), after second simple tonic-clonic, abnormal electrical activity
-Ambulatory EEG
-Video-Telemetry EEG recording
-MRI brain (first seizure under child 2yrs, focal, no response to first line antiepileptic)
-ECG to exclude heart problems, electrolytes, glucose, cultures, urine culture, LP.

Question 11

Common triggers of epilepsy

Answer 11

Sleep deprivation
Excessive Alcohol
Intercurrent illness / pyrexia
Hormonal factors
[Flashing Lights]

Question 12

Management of epilepsy

Answer 12

-Antiepileptic after second seizure
=After 1st seizure of neurological deficit, structural abnormality in brain imaging
-patients who drive: generally patients cannot drive for 6 months following a seizure. For patients with established epilepsy they must be fit free for 12 months before being able to drive
-Patients taking other medications: antiepileptics can induce/inhibit the P450 system resulting in varied metabolism of other medications, for example warfarin
-Women wishing to get pregnant: antiepileptics are generally teratogenic, particularly sodium valproate. It is important that women take advice from a neurologist prior to becoming pregnant, to ensure they are on the most suitable antiepileptic medication. Breastfeeding is generally considered safe for mothers taking antiepileptics with the possible exception of the barbiturates
-Women taking contraception: the possible interactions of the contraceptive and anti-epileptic medication need to be considered

Question 13

Examples of anti-epilepsy drugs

Answer 13

-Lamotrigine (female): sodium channel blocker
=SE: SJS

-Sodium Valproate (males): increases GABA activity, generalised seizures.
=SE: appetite and weight gain, alopecia, P450 enzyme inhibitor, ataxia, tremor hepatitis, pancreatitis, thrombocytopenia, teratogenic

-Carbamazepine: binds to sodium channels increasing refractory period, second line focal.
=SE: P450 enzyme inducer, dizziness and ataxia, drowsiness, leucopenia and agranulocytosis, SIADH, visual disturbances (diplopia)

-Levetiracetam

-Phenytoin: binds to sodium channels increasing refractory periods
=SE: P450 inducer, dizziness and ataxia, drowsiness, gingival hyperplasia, hirsutism, megaloblastic anaemia, peripheral neuropathy, osteomalacia, lymphadenopathy

-Phenobarbitone

For women taking phenytoin,carbamazepine, barbiturates, primidone, topiramate, oxcarbazepine:
UKMEC 3: the COCP and POP
UKMEC 2: implant
UKMEC 1: Depo-Provera, IUD, IUS

For lamotrigine:
UKMEC 3: the COCP
UKMEC 1: POP, implant, Depo-Provera, IUD, IUS

If a COCP is chosen then it should contain a minimum of 30 µg of ethinylestradiol.

Question 14

Epilepsy: pregnancy and breastfeeding

Answer 14

-aim for monotherapy
-there is no indication to monitor antiepileptic drug levels
-sodium valproate: associated with neural tube defects, neurodevelopmental delay
-carbamazepine: often considered the least teratogenic of the older antiepileptics
-phenytoin: associated with cleft palate
-lamotrigine: studies to date suggest the rate of congenital malformations may be low. The dose of lamotrigine may need to be increased in pregnancy
-Breast feeding is generally considered safe for mothers taking antiepileptics with the possible exception of the barbiturates
-It is advised that pregnant women taking phenytoin are given vitamin K in the last month of pregnancy to prevent clotting disorders in the newborn

Question 15

What is included in an assessment of drug therapy?

Answer 15

Seizure frequency
Seizure severity
Side effects
Quality of Life

Question 16

General advice for patients with epilepsy

Answer 16

Occupation
Hobbies
Driving- cannot drive for 6 months following seizure with no relevant structural abnormalities, established epilepsy= fit free for 12 months until able to drive
Insurance matters
Contraception & Pregnancy
Telling others/Stigma
SUDEP

Question 17

Describe epilepsy surgery

Answer 17

-For focal onset epilepsy
-Affecting a person’s life
-where drug treatment has failed

=Removing a focal part of the brain where seizures are arising
=Stopping spread of seizures from a focus

Question 18

What is SUDEP?

Answer 18

Sudden, Unexpected, Death
=In patients with epilepsy
=No other cause of death identified
=[No trauma, not overdose, no other disease etc]

-Seems to occur during or after a seizure
=But may be no seizure witnessed
=Often happens in sleep
[Not due to status epilepticus]

-600 SUDEP instances per year- 1:1000 risk on average

Question 19

What is status epilepticus?

Answer 19

CONVULSIVE STATUS
A Generalised Convulsive Seizure that lasts >5 minutes
Or
A second seizure occurring without person regaining consciousness after the first (within 5 minutes)
NON-CONVULSIVE STATUS

Question 20

Status epilepticus management

Answer 20

-Medical emergency

-ABC
=Airway adjunct
=High conc Oxygen
=Check blood glucose
-Benzodiazepine buccal midazolam or rectal diazepam (prehospital)/ IV lorazepam
=Repeat after 10 mins
=If persists use IV levetiracetam, phenytoin, or SV
=If no response (refractory status) within 45 mins, consider intubation and ventilation in ITU under GA , phenobarbital

Question 21

Describe generalised tonic-clonic seizure and drugs

Answer 21

these engage or involve networks on both sides of the brain at the onset
consciousness lost immediately. The level of awareness in the above classification is therefore not needed, as all patients lose consciousness
-generalised seizures can be further subdivided into motor (e.g. tonic-clonic) and non-motor (e.g. absence)

-Grand Mal
–Loss of consciousness
-Muscle tensing and muscle jerking
-Tongue biting
-Incontinence
-Groaning
-Irregular breathing
-Post-ictal period of confusion
-Drowsiness
-Irritable

=Sodium valproate (males). girls aged under 10 years and who are unlikely to need treatment when they are old enough to have children or women who are unable to have children may be offered sodium valproate first-line
=Lamotrigine, levetiracetam (females)
=Carbamazepine

Question 22

Describe focal seizure and drugs

Answer 22

-Temporal lobe= affects hearing, speech, memory, emotions
-Previously termed partial seizures
-the level of awareness can vary in focal seizures. The terms focal aware (previously termed ‘simple partial’), focal impaired awareness (previously termed ‘complex partial’) and awareness unknown are used to further describe focal seizures
=Last around 1 minute
-Hallucinations
-Memory flashbacks, déjà vu
-Lip smacking, grabbing, plucking
-Doing strange things on autopilot
-Aura= rising epigastric sensation

-Frontal= head or leg movements, posturing, post-ictal weakness, Jacksonian march (clonic movements travelling proximally)

-Parietal= paraesthesia

-Occipital= floaters/flashes

=1st: lamotrigine or levetiracetam
=2nd: carbamazepine

Question 23

Describe absence seizure and drugs

Answer 23

-Children
-Petit mal
-Blank and staring into space
-Unaware and no response

=first line: ethosuximide
=second line: sodium valproate (male), female: lamotrigine or levetiracetam
=carbamazepine may exacerbate absence seizures

Question 24

Describe atonic seizure and drugs

Answer 24

-Drop attacks
-Brief lapses in muscle tone

=SV male /Lamotrigine female

Question 25

Describe myoclonic seizure

Answer 25

Sudden brief muscle contractions like sudden jump, jerk

=SV male, levetiracetam female

Question 26

Clinical features of febrile convulsions

Answer 26

-Usually occur early in viral infection (first day, soon after onset of fever) as temperature rises rapidly (average 39)
-Seizures are usually brief, lasting less than 5 minutes
-Commonly tonic-clonic/ generalised tonic
-6months to 5 years, around 3% of children will have at least one febrile convulsion
-Seizures provoked by fever in otherwise normal children

Question 27

History of febrile seizure

Answer 27

When the fever started, peak temperature and duration, and any associated symptoms to suggest an underlying cause of febrile illness.
The relationship of the onset of fever to the seizure.
The characteristics and duration of the seizure to help classify whether it is simple or complex.
The duration of any post-ictal drowsiness.
Any previous seizure episodes.
Any recent antibiotic use (may mask signs of central nervous system infection).
Any recent immunizations, missed immunizations, or unknown immunization history. See the CKS topic on Immunizations - childhood for more information.
Neurodevelopmental history and any concerns.
Whether the child attends daycare such as nursery (source of potential exposure to infection).
Any family history of febrile seizures or epilepsy.

-Red flags:
=Irritability, neck stiffness, petechial rash, photophobia, bulging fontanelle, decreased consciousness, prolonged post0ictal period, focal neurological deficit

Question 28

Describe simple febrile convulsions

Answer 28

-Less than 15 minutes (usually less than 5)
-Generalised tonic-clonic type (muscle stiffening followed by rhythmical jerking or shaking of the limbs, which may be asymmetrical); twitching of the face, rolling back of the eyes, staring and losing consciousness.
-There may be foaming at the mouth, difficulty breathing, pallor, or cyanosis.
-A brief post-ictal period of drowsiness, irritability, or confusion, with complete recovery within 1 hour.
-Typically no recurrence within 24 hours

Question 29

Describe complex febrile convulsions

Answer 29

-15-30 minutes
-Focal seizure; A partial onset or focal feature (movement limited to one side of the body or one limb).
-May have repeat seizures within 24 hours
-There is incomplete recovery within 1 hour, and there may be prolonged post-ictal drowsiness or transient hemiparesis (Todd’s palsy).

-Febrile status epilepticus= >30 minutes

Question 30

Management of febrile convulsions

Answer 30

-First seizure/ complex seizure/less than 28 months= paediatrics
-First aid: cushion head, recovery position, time and observe
-Ambulance after 5 minutes
-Regular antipyretics not shown to reduce chance of febrile seizure occurring
-Benzodiazepines for recurrent convulsions (rectal diazepam, buccal midazolam)

Question 31

Advice to parents about febrile convulsions

Answer 31

Febrile seizures are not the same as epilepsy, and the risk of a child developing subsequent epilepsy is low.
Short-lasting seizures are not harmful to the child.
Most febrile seizures stop on their own within 2 to 3 minutes without any treatment.
About 1 in 3 children will have another febrile seizure.
The risk of febrile seizure reduces with age as the brain matures, and they are rare beyond 6 years of age.
Not all illnesses and episodes of fever will provoke a febrile seizure.

Question 32

Prognosis of febrile convulsions

Answer 32

the overall risk of further febrile convulsion = 1 in 3. This varies widely depending on risk factors for further seizure, including:
=age of onset < 18 months
=fever < 39ºC
=shorter duration of fever before the seizure
=a family history of febrile convulsions

-link to epilepsy
=risk factors for developing epilepsy include a family history of epilepsy, having complex febrile seizures and a background of neurodevelopmental disorder
=children with no risk factors have a 2.5% risk of developing epilepsy
=if children have all 3 features the risk of developing epilepsy is much higher (e.g. 50%)

Question 33

Alcohol withdrawal seizures

Answer 33

-Occur in patients with a history of alcohol excess who suddenly stop drinking, for example following admission to hospital
-Chronic alcohol consumption enhances GABA mediated inhibition in the CNS (similar to benzodiazepines) and inhibits NMDA-type glutamate receptors.Alcohol withdrawal is thought to be lead to the opposite (decreased inhibitory GABA and increased NMDA glutamate transmission)
-The peak incidence of seizures is at around 36 hours following cessation of drinking
-Patients are often given benzodiazepines following cessation of drinking to reduce the risk

Question 34

Psychogenic non-epileptic seizures

Answer 34

-Previously termed pseudoseizures, this term describes patients who present with epileptic-like seizures but do not have characteristic electrical discharges
-Patients may have a history of mental health problems or a personality disorder