Epilepsy: Causes

Pathogenesis (development of disease)

Epilepsy represents a functional disorder of the brain characterized by pathologic excitatory spreading. This involves seizure-like explosive discharges of central neurons (nerve cells). This can then manifest itself in very different symptoms depending on the exact location of the disorder. Triggers for an epileptic seizure are sleep disturbances (seizure triggering by arousal/degree of activation of the central nervous system, which is accompanied by increased sympathetic tone, which occurs when apnea (cessation of breathing) ends and causes unstable sleep), flickering light, fever (especially in children), discontinuation of anticonvulsants (antiepileptic drugs), and alcohol excesses. In women, seizure frequency is related to the menstrual phase. In this regard, estrogens are thought to have a seizure-promoting effect and progesterone (progestin) a seizure-inhibiting effect:

  • Perimentrual (around the time of menstruation) with a typical drop in progestin at the end of the cycle (day 3).
  • Periovulatory peak (increase at the time around ovulation) (day 10-13).
  • Second half of the cycle in disorders of luteal function (corpus luteum insufficiency/gelboreal hormone deficiency); day 10 to day 3 of the subsequent cycle.

Note: Pediatric patients with status epilepticus have known neurologic history or epilepsy in approximately 50% of cases, and status predisposition is usually already known.

Etiology (causes)

Biographic causes

  • Genetic burden from parents, grandparents
    • Causes of epilepsies in children include mutations in the sodium channel gene SCN2A
    • Idiopathic generalized epilepsy: altered genes encoding inhibitory GABAA receptors.

Behavioral causes

  • Nutrition
    • Micronutrient deficiency (vital substances) – see Prevention with micronutrients.
  • Consumption of stimulants
  • Drug use
  • Sleep deprivation – willful or involuntary deprivation of sleep.

Disease-related causes

  • Alzheimer’s disease
  • Abnormalities (malformations) of the central nervous system.
  • Circulatory disorders in the brain
  • Electrolyte shifts – changes in water balance.
  • Developmental disorders in children
  • Encephalitides (brain inflammations): including autoimmune encephalitis – encephalitis triggered by immunoglobulin class G (IgG) antibodies against the body’s own tissues; immunoglobulins against NMDA receptors and the so-called leucine-rich glioma inactivated protein 1 (LGI1) have been identified as the most common triggers of antibody-mediated encephalitis; the different triggers lead to different clinical pictures:
  • Fever → febrile convulsion, prolonged (thus complicated) (about 30% of cases in children with status epilepticus).
  • Cerebral hemorrhage
  • Brain tumors
  • Brain metastases (daughter tumors from other parts of the body).
  • Hormonal disorders (affecting women: estrogens are thought to have a seizure-promoting effect; progesterone has a seizure-inhibiting effect).
  • Infections
  • Intoxications (poisonings)
  • Liver failure
  • Drug withdrawal
  • Kidney failure
  • Pyridoxine (vitamin B6) deficiency in the newborn baby.
  • Traumatic brain injury (TBI)
  • Toxoplasmosis – 2.25 times higher risk of epilepsy.
  • Vasculitides (vascular inflammation due to autoimmune diseases).

Laboratory diagnoses – laboratory parameters that are considered independent risk factors.

  • Hyperglycemia (hyperglycemia).
  • Hypernatremia (excess sodium)
  • Hypocalcemia (calcium deficiency)
  • Hypoglycemia (hypoglycemia)
  • Hyponatremia (sodium deficiency)
  • Hypomagnesemia (magnesium deficiency)

Medication

Operations

  • Surgery on the brain may result in a seizure as a complication

Environmental pollution – intoxications (poisonings).

  • Strobe lights in clubs → patients with known photosensitive epilepsy should avoid such events or take precautions

Other causes

  • Contrast agent in radiology