Epilepsy: Pathogenesis
Genetic susceptibility
Angelman syndrome, Fragile X syndrome, Tuberous sclerosis, neurofibromatosis
Chromosomal abnormalities cause abnormal neural patterns
Neural
Cerebral palsy, focal cortical dysplasia
Malformation of cortical development
Cerebrovascular
Intracranial hemorrhage, ischemic stroke
Other Acquired
Head trauma, cerebral infection (i.e., HSV1, VZV, cysticercosis)
Neoplasm
Metabolic
Inborn errors of metabolism
Inherited enzyme deficiencies
Neurodegenerative
Alzheimer’s Disease
Protein-rich plaque build-up and brain atrophy
Inflammation and formation of scar tissue irritates neural tissue
Infiltration of mass, grey matter irritation
Damage to the brain and subsequent alteration of neuronal circuitry
Neurotransmitter imbalances (i.e. ↑ glutamate, ↓ GABA, ↓ serotonin, ↓ dopamine, ↓ noradrenaline)
Abbreviations:
• HSV1 – Herpes Simplex Virus 1 • VZV – Varicella Zoster Virus
↑ Inflammatory cytokines (e.g. interleukin-6, tumor necrosis factor-α)
Altered neurogenesis and gliosis
Ion channel and receptor dysfunction causes imbalance of ion channel charges
Authors: Keerthana Pasumarthi Christopher Li Reviewers: Negar Tehrani, Ephrem Zewdie, Ran (Marissa) Zhang, Carlos R. Camara-Lemarroy* * MD at time of publication
Neurons fire in burst activity (referred to as paroxysmal depolarization shift) and often in groups (hypersynchrony)
Abnormal neural activities eventually create self-reinforcing circuits and transform neural network over time
Injuries from
falls, bumps, operating heavy machinery
Involuntary contractions Loss of consciousness
Post-ictal confusion
Recurrent seizures
Sudden Unexplained Death of Epilepsy Patient (SUDEP)
Loss of airway reflexes
Aspiration of saliva or food contents
Aspiration Pneumonia
Legend:
Pathophysiology
Mechanism
Sign/Symptom/Lab Finding
Complications
Published July 5, 2022 on www.thecalgaryguide.com