Epilepsy Flashcards
What is the differential diagnosis for a blackout?
- Syncope
- First seizure
- Hypoxic seizure
- Concussive seizure
- Cardiac arrhythmia
- Non-epileptic attack
- Less common reasons (narcolepsy, movement disorders, migraine)
How do you differentiate between the causes of blackout?
- Detailed history from patient
- Detailed history from witness
- (Tests)
What history should you try to take from the patient?
- What were they doing at the time?
- What, if any, warning feelings did they get?
- What were they doing the night before?
- Have they had anything similar in the past?
- How did they feel afterwards?
- Any injury, tongue biting or incontinence?
What history should you try and take from the witness?
- Detailed description of observations before and during attacks - including level of responsiveness, motor phenomena, pulse, colour, breathing, vocalisation
- Detailed description of behaviour following attacks
What information about the patient may be relevant to differentiate the cause of a blackout?
- Age
- Sex
- Past medical history including head injury, birth trauma and febrile convulsions
- Past psychiatric history
- Alcohol and drug use
- Family history
What is the most common cause of fainting?
Vasovagal syncope
What is the prodrome to syncope?
- Light-headed, nausea
- Hot, sweating
- Tinnitus
- Tunnel vision
What are the potential triggers for vasovagal syncope?
- Prolonged standing
- Standing up quickly
- Trauma
- Venepuncture
- Watching/experiencing medical procedures
- Micturition
- Coughing
In what posture does syncope usually occur?
Upright posture
In what posture does seizure usually occur?
Any posture
What is the onset speed of syncope?
Gradual onset
What is the onset speed of seizure?
Sudden onset
Does injury usually occur in syncope?
It is rare
Does injury usually occur in seizure?
It is quite common
Does incontinence usually occur in syncope?
It is rare
Does incontinence usually occur in seizure?
It is common
What is the recovery speed of syncope?
Rapid recovery
What is the recovery speed of seizure?
Slow recovery
Does syncope usually have a precipitant?
It is common
Do seizures usually have precipitants?
It is rare
Does pallor usually occur in syncope
It is common
Does pallor usually occur in seizure?
It is uncommon
When do hypoxic seizures occur?
Occur when individuals are kept upright in a faint
Where can hypoxic seizures occur?
Can occur in aircraft, at the dentist, when well-meaning passersby help people to their feet….
What may occur in hypoxic seizures?
- Patient may have a succession of collapses
- Seizure like activity may occur
When can concussive seizures occur?
After any blow to the head
What can cause cardiac arrhythmias?
- Structural cardiac abnormalities
- Functional cardiac problems e.g. Long QT syndromes
When should cardiac arrhythmias be considered as the cause of blackout?
Consider particularly when there is a family history of sudden death, when there is a cardiac history and when collapse occurs with exercise
What can initiate a cardiac arrhythmia?
Seizure
Who do non-epileptic attacks usually affect?
Women
Hoe do non-epileptic attacks usually present?
- Can be frequent
- May look bizarre
- Can be prolonged
What may there be a history of in non-epileptic attacks?
- May have a history of other medically unexplained symptoms
- May have history of abuse
What may non-epileptic attack resemble?
- May superficially resemble a generalised tonic-clonic seizure
- May resemble a swoon
What investigations should be carried out for a possible first seizure?
- Blood sugar
- ECG
- Consider effects of alcohol and/or drugs
- CT head
What advice should be given to patients following a possible first seizure?
- Give copies of safety information sheets and information about the first seizure clinic
- Enquire about their employment – they may need to inform their employer
- Enquire about potentially dangerous leisure activities
- Explain the driving regulations
What are the driving regulations for someone who has suffered a seizure?
- After a first seizure, a patient may drive a car after 6 months if their investigations are normal and they have had no further events
- They may drive an HGV or PSV after 5 years if their investigations are normal, they have no further events and they are not on anti-epileptic medication
When is epilepsy usually diagnosed?
Normally diagnosed after a second unprovoked attack but sometimes on taking the history after a first seizure, it is clear that they have undiagnosed epilepsy.
What features are suggestive of epilepsy?
- History of myoclonic jerks, especially first thing in the morning, absences or feeling strange with flickering lights – in keeping with a primary generalised epilepsy
- History of “deja vu”, rising sensation from abdomen, episodes where look blank with lip-smacking, fiddling with clothes – suggest a focal onset epilepsy
What is an epileptic seizure?
An epileptic seizure is an intermittant stereotyped disturbance of consciousness, behaviour, emotion, motor function or sensation which, on clinical grounds, is believed to result from abnormal neuronal discharges
What is epilepsy?
A condition in which seizures recur, usually spontaneously
What is the incidence of epilepsy?
Incidence: 50 - 120 per 100 000 per year
What is the prevalence of epilepsy?
Prevalence: 5 – 8 per 1000 (Aberdeen 0.9%)
What is the correlation between learning disabilities and epilepsy?
22% of people with learning difficulties have epilepsy
How is epilepsy classified?
- The International League Against Epilepsy (ILAE) have classified epileptic seizures into groups using clinical data and electroencephalography (EEG) evidence
- They have also produced a classification of epilepsy syndromes
What are the ILAE epilepsy classifications of generalised seizures?
- Generalised Seizures:
- Tonic-clonic seizures
- Myoclonic seizures
- Clonic seizures
- Tonic seizures (stiffening movements)
- Atonic seizures (really rapid drop to the floor)
- Absence seizures (looks as if they aren’t paying attention/may not even notice, short lasting)
What are focal seizures characterised according to?
- Aura
- Motor features
- Autonomic features
- Degree of awareness or responsiveness
What can focal seizures evolve into?
Generalised convulsive seizure
Do you get a warning with a primary generalised seizure?
No warning
Who is usually affected by primary generalised seizures?
<25 years
What may there be a history of in primary generalised seizures?
May have history of absences and myoclonic jerks as well as GTCS e.g in juvenile myoclonic epilepsy
What may be seen on EEG of primary generalised seizures?
Generalised abnormality on EEG
Is there a family history in primary generalised seizures?
May have a family history
What may you get before a focal/partial seizure?
May get an aura
Who is usually affected by focal/partial seizures?
At any age as cause can be any focal brain abnormality
What can simple partial and complex partial seizures become?
Secondarily generalised
What may be seen on EEG of a focal/partial seizure?
Focal abnormality on EEG
What may an MRI show with regards to focal/partial seizures?
MRI may show underlying cause
How can epilepsy present in learning difficulties?
- Patients can have unclassifiable seizures which are unique to them
- They can also have repetitive movements and apparently fairly stereotyped events which are behavioural but which can be difficult to diagnose
What investigations should be carried out when diagnosing epilepsy?
- EEG for primary generalised epilepsies including hyperventilation and photic stimulation: sometimes sleep deprivation
- MRI for patients under age 50 with possible focal onset seizures: CT usually adequate to exclude serious causes over this age
- Video-telemetry if uncertainty about diagnosis
What is the first line treatment for primary generalised seizures?
- Sodium valproate
- Lamotrigine
- Levetiracetam
What is the first line treatment for partial and secondary generalised seizures?
Lamotrigine or carbamazepine
What is the first line treatment for absence seizures?
Ethosuximide
What is the first line treatment for status epilepticus?
- Midazolam: 10mg by buccal or intra-nasal route, repeated after 10mins if necessary
- Lorazepam: 0.07mg/kg, usually 4mg bolus repeated once after 10 mins
- Diazepam: 10 - 20mg iv or rectally, repeated after 15 mins if necessary
What is the second line treatment for status epilepticus?
- Phenytoin - slow infusion of 15 – 18mg/kg at 50mg/min
- Valproate – 20 -30mg/kg iv at 40mg/min
What can be used IV for status/near status?
Levetiracetam
What is the second line treatment for generalised epilepsy?
- Topiramate
- Zonisamide
- (Carbamazepine)
What is the second line treatment for partial seizures?
- Sodium valproate
- Topiramate
- Leviteracetam
- Gabapentin
- Pregablin
- Zonisamide
- Lacosamide
- Perampanel
- Benzodiazepines
What are the possible side effects of sodium valproate?
- Tremor
- Weight gain
- Ataxia
- Nausea
- Drowsiness
- Transient hair loss
- Pancreatitis
- Hepatitis
What are the possible side effects of carbamazepine?
- Ataxia
- Drowsiness
- Nystagmus
- Blurred vision
- Low serum sodium levels
- Skin rash
What are the possible side effects of lamotrigine?
- Skin rash
- Difficulty sleeping
What are the possible side effects of levetiracetam?
- Irritability
- Depression
What are the possible side effects of topiramate?
- Weight loss
- Word-finding difficulties
- Tingling hands and feet
What are the possible side effects of zonisamide?
- Bowel upset
- Cognitive problems
What are the possible side effects of lacosamide?
-Dizziness
What are the possible side effects of pregablilin?
-Weight gain
What are the possible side effects of vigabatrin?
Behavioural problems and visual field defects
What is the driving restriction for someone with epilepsy?
- Patients can hold a Group 1 licence once they have been seizure free for a year or have only had seizures arising from sleep for a year. If they have ever had a day time seizure but then the pattern becomes noctural, this must be established for three years before they can drive
- They can only hold a HGV or PSV licence if they have been seizure free for 10 years and are not on anti-epileptic medication
What is status epilepticus?
Prolonged or recurrent tonic-clonic seizures persisting for more than 30 minutes with no recovery period between seizures
How many cases of status are there a year?
9,000 - 14,000 cases /year in the U.K
Who does status usually occur in?
Usually occurs in patients with no previous history of epilepsy (stroke, tumour, alcohol)
What is the mortality rate of status?
5-10%
What is the 3rd line treatment for status epilepticus?
Anaesthesia usually with propofol of thiopentone
What is the outcome of status?
- Mortality greatest in very young and very old (29% of those < 1 year)
- 90% of deaths are a result of the underlying cause
- Mortality is highest secondary to strokes, encephalitis, mass lesions and trauma
- However in children the status itself is important - neurological problems reported in 24% following episode of status.
What does SUDEP stand for?
Sudden unexplained death in epilepsy
