Epidemiology

Etiology

Etiologies are broadly categorized as provoked (acute symptomatic) or unprovoked (related to a static or progressive underlying condition).

Common Causes (VITAMINS mnemonic):

• Vascular: Stroke (ischemic or hemorrhagic) is the most common cause in adults, especially the elderly. AVMs.
• Infection: Meningitis, encephalitis, brain abscess, neurocysticercosis (most common cause worldwide).
• Trauma: TBI can cause acute seizures or lead to post-traumatic epilepsy.
• Autoimmune: e.g., Anti-NMDA receptor encephalitis, lupus cerebritis.
• Metabolic: Hypoglycemia, hyponatremia, hypocalcemia, uremia, hepatic encephalopathy.
• Idiopathic/Genetic: Significant portion of childhood-onset epilepsies. Examples include juvenile myoclonic epilepsy, childhood absence epilepsy.
• Neoplasms: Primary or metastatic brain tumors. Seizures can be the presenting symptom.
• Substances:
  • Withdrawal: Alcohol, benzodiazepines, barbiturates.
  • Toxicity/Overdose: Cocaine, amphetamines, TCAs, bupropion, tramadol, theophylline.

Etiology by Age

• Neonates (<1 mo): Hypoxic-ischemic encephalopathy (HIE), intracranial hemorrhage, CNS infection, metabolic disturbances (hypoglycemia, hypocalcemia), congenital brain malformations.
• Infants/Children (1 mo - 12 yr): Febrile seizures (most common), genetic epilepsy, CNS infections, trauma, developmental disorders.
• Adolescents (12 - 18 yr): Trauma, genetic epilepsy (e.g., JME), infection, illicit drug use, brain tumors.
• Young Adults (18 - 35 yr): Trauma, alcohol withdrawal, illicit drug use, brain tumors.
• Older Adults (>35 yr): Cerebrovascular disease (stroke), brain tumors, alcohol withdrawal, metabolic disorders (e.g., hypoglycemia).

Pathophysiology

Clinical features

Diagnostics

Treatment

Acute management

• Early status epilepticus (5–20 minutes): first-line therapy
  • IV benzodiazepine (lorazepam OR diazepam)
• Persistent status epilepticus (20–40 minutes): second-line therapy
  • IV fosphenytoin
  • IV valproic acid
  • IV levetiracetam
• Refractory status epilepticus (40–60 minutes)
  • Options include repeat second-line therapy or induction of coma (e.g., with IV propofol, thiopental, midazolam, or pentobarbital).

Long-term management

• Focal
  • Lamotrigine
  • Levetiracetam
  • Phenytoin
  • Carbamazepine
  • Oxcarbazepine
  • Phenobarbital (children)
• Generalized
  • Tonic-clonic
    • Lamotrigine
    • Valproate
    • Phenobarbital (children)
  • Typical absence
    • Ethosuximide
    • Valproate
  • Atypical absence
    • Valproate
  • Myoclonic
    • Valproate
    • Lamotrigine
    • Topiramate
  • Atonic
    • Valproate