Epilepsy Flashcards
Define epilepsy
Recurring tendency to have seizures
- At least 2 unprovoked seizures >24 hours apart
- 1 unprovoked seizure + probability of further seizures similar to general recurrence risk (60%) after 2 unprovoked seizures occurring over the next 10 years
Define seizure
Excessive, abnormal and synchronised electrical activity that leads to external manifestations. Can be provoked or unprovoked
What defines a prolonged and pseudo-seizure
Prolonged seizure = seizure activity ≥5 minutes
Pseudo-seizure= The patient believes to be having a seizure
What is the cause of epilepsy
Most epilepsy (70-80%) is genetic/idiopathic with complex inheritance
Primary epilepsy syndromes e.g. idiopathic generalised, temporal lobe, juvenile myoclonic
Secondary: tumours, CNS infection, vasculitis, electrolyte abnormalities, drugs, haemorrhage/infarction, malignant hypertension, TBI
What are the childhood epileptic syndromes
Infantile spasms (West syndrome)
Lennox-Gastaut
Childhood absence epilepsy
Epilepsy with centro-temporal spikes (Childhood rolandic epilepsy)
Panayiotopoulos syndrome (early-onset benign occipital epilepsy)
Juvenile absence epilepsy
Juvenile myoclonic epilepsy
What is the difference between generalised and focal epilepsy and which types of epilepsy fall in each group
Generalised: Discharge arises from both hemispheres
- Convulsive: tonic, clonic, tonic-clonic, myoclonic
- Non-convulsive: absent, atonic
Focal: Seizures arise from one or part of one hemisphere. Each one will produce different symptoms. Originates in a relatively small group of dysfunctional neurones
- Simple partial: no loss of consciousness
- Complex partial: May have a loss of consciousness
What is the classification of epilepsy according to the International League Against Epilepsy 2017
- Where they begin: focal, unknown, generalised, focal to bilateral
- Level of awareness: focal aware, focal impaired, awareness unknown, generalised
- other features
- Focal: motor onset (twitching, jerking, stiffening, automatisms) or non-motor (cognitive, emotional, sensory)
- Generalised onset: motor (tonic clonic) or non-motor (absence, awareness changes, automatisms)
What is the aetiology and risk factors of epilepsy
Most genetic/idiopathic (70-80%)
Family history
Perinatal asphyxia
Metabolic disorders
Febrile seizure
Head trauma
CNS infection or tumour
Cerebral palsy
Learning disabilities
Down’s syndrome
What is the epidemiology of epilepsy
0.05% incidence (less common during the first year of life) and a prevalence of 0.5%
Peak age of onset in early childhood or in the elderly <20, >60
Males > females
What are the signs and symptoms that suggest a generalised seizure
Before: Epileptic aura, triggers e.g. flashing lights
During: stiffness, jerking, incontinence, tongue-biting, sweating, palpitations, mouth frothing, pallor, cyanosis
After: Muscle ache, post-ictal confusion, drowsiness
Describe absence seizures
Transient loss of consciousness
Abrupt onset and termination
May see flickering of the eyelids and minor alteration in muscle tone, otherwise NO motor phenomena
May be precipitated by hyperventilation
Describe myoclonic seizures
Brief, repetitive, jerking movements of the limbs, neck or trunk
Includes benign rolandic epilepsy and juvenile myoclonic epilepsy
Describe the types of childhood myoclonic epileptic disorders
Benign Rolandic Epilepsy (BRE) (most common childhood epilepsy) / Sylvian seizures
3-12yo
S/S: seizures of face / upper limbs during sleep with hypersalivation & speech arrest
Childhood (age 3-12yo) seizures – outgrown at end of puberty
Juvenile myoclonic epilepsy
12-18yo
Usually involving neck, shoulders, upper arms, most occur after waking up
Begin around puberty
Describe tonic epileptic seizures
Generalised increase in tone
Describe tonic-clonic seizures
- Tonic phase - children may fall to the ground, sometimes injuring themselves
- May not breathe → cyanosis - Clonic phase - Rhythmical contraction of muscle groups → jerking of limbs
- Breathing may be irregular as cyanosis persists and saliva accumulates in the mouth
- May show biting of the tongue and incontinence of urine - Post-ictal phase:
- followed by unconsciousness or deep sleep for up to several hours
Describe atonic seizures
Often combined with myoclonic jerk, followed by a transient loss of muscle tone causing a sudden fall to the floor or drop of the head
Describe frontal focal epileptic seizures
Behavioural changes
Motor: posturing, peddling, motor arrest (dysphasia, speech arrest)
± Jacksonian March: As the seizure increases in size, more of the homunculus becomes affected i.e. hand shaking → elbow shaking → Arms shaking
± Todd’s paralysis: Post-ictal flaccid weakness
Describe temporal focal epileptic seizures
Aura (visceral and psychic symptoms - fear or deja-vu sensation)
Hallucinations (smell, taste)
Emotional disturbance
Depersonalisation
Automatisms e.g. lip-smacking, fumbling, fiddling, chewing, singing, kissing)
Describe parietal focal epileptic seizures
Sensory disturbances: tingling, numbness
Motor symptoms: abnormal movements, rhythmic muscle contractions
Describe occipital focal epileptic seizures
Visual phenomena: spots, lines, flashes
What investigations should be done for epilepsy
Bedside: ECG, urine dip, BM
Bloods: Glucose, U&Es, FBC, genetic testing, toxicology, serum prolactin, CRP/ESR
Other: MRI brain, EEG (inter-ictal, ictal, sleep-deprived), /CT head/PET/SPECT, ± LP
What is the management for a child with a first fit
Urgent referral to hospital for paediatric assessment
Referral to first fit clinic
What is the long term management for epilepsy
Advice and safety netting
MDT management (paeds, neuro, school nurse, epilepsy nurse, GP)
Anti-epileptic monotherapy (usually valproate)
Rescue therapy (seizures >5mins): Buccal midazolam
What anti-epileptics are indicated in tonic-clonic seizures
First line: sodium valproate, carbamazepine
Second line: clozabam, levetiracetam, Topiramate
What anti-epileptics are indicated in myoclonic seizures
First line: sodium valproate, levetiracetam
Second line: clozabam, clonazepam
What anti-epileptics are indicated in absence seizures
First line: valproate, ethosuximide
Second line: clozabam, lecetiracetam, topiramate
What anti-epileptics are indicated in focal seizures
First line: carbamazepine, valproate, levetiracetam, lamotrigine
Second line: clozabam, topiramate, gabapentin
What are the treatment options for intractable epilepsy
Ketogenic (low-carb, fat-based) diets
Vagus nerve stimulation or responsive neurostimulation system
- delivered using externally programmable stimulation of a wire implanted around the afferent (left) vagus nerve
Resective epilepsy surgery (lobectomy, hemispherotomy
- For epilepsy has a well-localised structural cause or epileptogenic zone
- Demonstrated by good concordance between ictal EEG, MRI, functional imaging findings
What advice should be given for children with epilepsy
How to recognise a seizure
Video record future seizure
Avoid dangerous activities (i.e. swimming or deep baths) unsupervised
Ensure school is informed
Support: epilepsy action
Adolescents → 1 year free of seizures is safe to drive, may interact with contraception, affects pregnancy outcomes
Avoid alcohol, drugs, poor sleep
Define status epilepticus
Continuous seizure activity ≥ 30 minutes or repetitive seizures with no intervening recovery of consciousness
What is the management for status epilepticus
0mins:
- A-E
- High flow oxygen if available
- Check BM and confirm it is epileptic seizure
5mins:
- Buccal midazolam / rectal diazepam
- IV established: IV lorazepam
15mins:
- IV lorazepam
- Call senior
- Re-assess, confirm epilepsy
25mins:
- IV phenytoin/IV phenobarbitone (if already on phenytoin)
- Call anaesthetics and inform ICU
45mins: Rapid sequence induction of anaesthesia with thiopental, PICU transfer
What are the complications of epilepsy
Falls and injuries → Fractures
Aspiration
Status epilepticus - respiratory arrest
SUDEP - sudden death in epilepsy
Depression and anxiety disorders
Absence from school, learning difficulties
What is the prognosis for epilepsy
50% remission at 1 year
Mortality 2 in 100,000/year
Related to seizure or secondary to injury
Children with epilepsy do less well educationally, with social outcomes and future employment compared to others with chronic conditions e.g. diabetes
2/3 of children go to mainstream school but some may need educational help for associated learning difficulties.
1/3 go to special schools but often have multiple disabilities and their epilepsy is part of a severe brain disorder.
Few children require residential schooling
What are the side effects of anti-epileptics
Valproate: weight gain, hair loss, rare idiosyncratic liver failure, teratogenic (DO NOT give to female children/adolescents, women of childbearing potential or pregnant women
Carbamazepine: rash, neutropoenia, hyponatraemia (SIADH), ataxia, inducer
Lamotrigine: severe skin rash (SJS)
Levetiracetam: sedation (rare)
