Epilepsy

• Chronic disorder characterised by recurrent seizures
• May vary from brief lapse in attention or muscle jerks to severe and prolonged convulsions
• Seizure: clinical phenomenon due to abnormal, synchronous, cortical discharges
• Working definition of epilepsy: two or more seizures w/o clear symptomatic provocation
• 400,000 people in UK

Vasovagal syncope

Seizure

Cardia syncope

Cataplexy

Hypoglycaemic attack 

• Syncope= sudden impairment of consciousness and loss of tone
• Due to reduced blood/O2 to brain
• Often a provoking factor- clood, pain, deghyr=dration etc
• Presyncopal symptoms
  • Light-headness, warmth, dizziness building in intensity, possible loss of vision/hearing
• Stiffening and jerking common
• Urinary and faecal incontinence may occur

• Sudden LOC w/ brief/no warning and rapid recovery
• Cardiac Hx
• FHx of sudden death
• Thus, all pt w/ transient LOC should have ECG
• ECG “clues”
  • Long QT interbal
  • Prior MI
  • Anterior (V1-3) T inversion
  • QRS duration in V1-3/V4-6 > 1.2 = RV dysplasia
  • Ectopy
  • Bradycardia
  • AV delay/block
  • Bifascicular block
  • Ventricular hypertrophy

• No LOC
• Provoked by emotion
• Nearly always in context of narcolepsy
• Assoc freq dreams, sleep paralysis
• Dx- sleep latency test- rapid falling asleep + rapid onset of REM
• CSF shows decr/absent hypocretin
  • = neuropeptide that regulates arousal, wakefulness, and appetite

• collateral history important
• if suspect syncopal:
  • ECG
• if suspect seizure
  • MRI
    • good for subtle abnormalities e.g. hippocampal sclerosis > temporal lobe epilepsy
  • EEG (maybe)

• UK- start therapy after 2 spontaneous seizures as high risk of further seizure
• Start after 1 tonic-clonic if Hx of partial, absence or myoclonics or if risk to safety if another seizure occurs e.g. if need to drive
• Do not start if very infrequent tonic-clonic, simple/complex partial seizures, woman of child bearing age (teratogenicity)
• NB- DVLA to drive need:
• Single seizure w/ imaging and EEG unsupportive of epilepsy – 6 months
• Epilepsy – 12 months seizure free

• Barbiturates – incr GABA – partial
• Benzodiazepines – incr GABA – status
• Carbamazepine – inhib Na channels – TC
• Phenytoin – inhib Na and Ca channels – status
• Valproate – incr GABA and inhib NA channels – partial, TC, absence
• Levetiracetam – inhib synaptic conduction – partial
• Lamortrigine – inhib Na channels – partial, TC
• Topiramate – prob decr glutamate (NK) 
  • Lev, lam and top are new- more ££, not more effective, improved s/e, interaction, tolerability, some a/e found after years of use