Epilepsy and Epileptic Syndromes
Tis very like: he hath the falling sickness-Julius Caesar, by William Shakespeare
It is thought Caesar was prone to seizures, where uncoordinated electrical activity in his brain caused him to experience complex prodromal symptoms such as Aura or Deja vu, before falling unconscious to the floor, convulsions wracking his body, first by stiffening(Tonic), then jerking wildly(Clonic), followed by a post-ictal phase of drowsiness & headache.
- First ever seizure: Is this really the first? Can they think of anything that might have triggered it(Drugs, Diabetes)
- Absence: Pauses of conciousness < 10s
- Tonic Clonic: Loss of conciousness, limbs stiffen then jerk. Post ictal confusion and drowsiness
- Atonic (drop): Sudden fall as tone is lost, no loss of conciousness
- Simple: No change in awareness. Focal motor/ sensory, no post-ictal phase
- Complex: Impaired awareness. May have aura. Post-Ictal confusion
- Partial leading to General in 2/3 of patients, see above.
Driving Guidance (Class 1)
- First seizure- No driving for 6 months.
- Epilepsy- no driving for 12 months post seizure. Antiepileptics may also cause drowsiness, preventing driving.
Note that treatment is not started after the first epileptic event. Specialist referral, followed by EEG, may diagnose epilepsy, indicating the following treatments:
- Sodium Valproate/Lamotrigene: For Generalised Tonic Clonic, Absence, Atonic, Myoclonic
- Carbamazepine: For partia, Partial→Generall, and second line for above except atonic and myoclonic.
Beware Status Epilepticus- prolonged tonic clonic seizure > 30 mins may cause brain damage. Remember your ABCs, then Benzodiazepines & Phenytoin play a role in management.
- Idiopathic (majority)
- Congenital defects
- Space occupying lesion
- Raised Intracranial Pressure
- Alcohol/ Diazepam withdrawal
- Infection: Meningitis, Encephalitis, Syphilis
- Drugs: Cocaine
- Tuberous Sclerosis
- Systemic Lupus Erythematous
Paediatric Epileptic Syndromes
- Signs: bradycardia, and are usually atonic or tonic clonic. Eye deviation, disorientation and agitation are common. Usually followed by sleep.
- Causes: Include reflex anoxic seizures in ages 12-24 months. These immediately follow a fright and can feature a brief period of asystole. Blue breath holding is also a common cause between 6 months and 5 years, after a cyanotic period due to crying, featuring a brief loss of consciousness. Other causes include vasovagal syncopy and cardiac pathology (such as long QT syndrome).
- Signs: Child or parent fabricated seizure
- Causes: The child may be emulating a family member.
- Signs: Occur during sleep, particularly in slow wave sleep. Can feature night terrors, which are particularly distressing for child and parent.
- Causes: Benign neonatal sleep myoclonus is a rare cause.
Metabolic/ Drug-related Seizures
- Causes: Hypoglycaemia and substance abuse are differential diagnoses of seizures in childhood. Moreover, child or adolescent use of carbamazepine can induce an oculogyral crisis.
Classification of Epileptic Seizures
Epileptic seizures can be classified as generalised, which always feature a loss of consciousness, or focal. Types of generalised seizures include:
- Absence: Transient, no motor phenomena
- Myoclonic: brief, jerking movements of limbs, neck and trunk
- Tonic: generalised increase in tone
- Tonic-clonic: Rigid tonic phase, with rhythmic contractions. This is followed by irregular breathing and cyanosis, and can feature tongue biting.
- Atonic: myoclonic jerk and decreased muscle tone
- Age: 4-6 months
- Signs: violent flexor spasms of head, trunk and limbs. May occur 20-30 times during one episode.
- Associated with: developmental problems and epilepsy
- Treatment: vigabatrin/corticosteroids
- Age: 1-3 years
- Signs: Frequent seizures of multiple types. Myoclonic episodes with single jerks. Drop attacks occur with neurodevelopmental arrest.
- Associated with: Poor progression
Benign Epilepsy with Rolandic Spikes
- Age: Until teenage years
- Signs: Generalised tonic-clonic, with face distortion, on one side, with an abnormal sensation in the tongue.
- Associated with: Cessation at mid-teens
Juvenile Myoclonic Epilepsy
- Age: 10-20 years
- Signs: Myoclonic/ absence/ tonic-clonic seizures, especially after waking. This is often described as 'cornflake throwing'.
- Associated with: Increased incidence in females, and in patients with family history. Learning is unimpaired and there is good treatment response.