Seizures and epilepsy
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A seizure refers to a one-time event caused by abnormal, excessive, and synchronous electrical activity in the brain that can result in autonomic, sensory, and motor symptoms. When seizures specifically involve motor activity, like jerking, we call them convulsions. Most seizures last less than 5 minutes, but if the seizure continues for 5 minutes or more, it’s called status epilepticus.
Keep in mind that seizures are a symptom, not a diagnosis, meaning they can occur due to various underlying causes, such as trauma, infections, and metabolic imbalances. However, when seizures arise without a clear cause, they are considered unprovoked. And if someone experiences two or more unprovoked seizures, at least twenty-four hours apart, think epilepsy.
Normally, the brain and its neurons rely on a balance between excitatory and inhibitory neurotransmitters. Think of excitatory neurotransmitters like green traffic lights that speed things up, encouraging the neuron to pass electrical impulses to the next one. On the other hand, inhibitory neurotransmitters act like red traffic lights that slow traffic down, stopping the further propagation of electrical impulses.
Now, whether there’s too much excitation or not enough inhibition, neurons can begin firing impulses simultaneously. This leads to abnormal, excessive, and synchronous electrical activity in the brain, which results in a seizure.
Now, there are various causes of seizures, and you can remember the most important ones using the mnemonic “VITTAMINS”. “V” stands for Vascular conditions, like strokes and intracranial hemorrhage, and “I” covers Infection, including meningitis, encephalitis, and brain abscess. Next, the first “T” refers to head Trauma, while the second “T” refers to Toxins, such as cocaine or amphetamine overdose, but also alcohol withdrawal. “A” is for Autoimmune conditions, such as CNS vasculitis and lupus; and “M” is for Metabolic conditions, including hepatic- and uremic encephalopathy, as well as electrolyte disturbances, such as hyponatremia. The second “I” is for Idiopathic, meaning no identifiable cause, which refers to epilepsy. Finally, “N” is for neoplasm or brain tumors, and “S” covers differential diagnoses like Syncope, pSychogenic seizures, and migraineS.
- "Davidson's Principles and Practice of Medicine. Available from: ClinicalKey Student, (24th Edition). Page 1152 – 1157 " Elsevier Limited (UK), (2022)
- "Conn's Current Therapy 2024. Available from: ClinicalKey Student, Page 803 – 812 " Elsevier Limited (UK) (2023)
- "Netter's Neurology. Available from: ClinicalKey Student, (3rd Edition). Page 278 – 292 " Elsevier Health Sciences (US)
- "USMLE Step 1 Secrets in Color. Available from: ClinicalKey Student, (5th Edition). Page 437 " Elsevier Limited (UK) (2022)
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