Seizures
Definition: excessive abnormal electrical activity of the brain leading to a clinical event
-Epilepsy is a condition where a person has recurrent seizures due to a chronic, underlying process
-Status epilepticus – patient has recurrent seizures without regaining consciousness between each episode, can be fatal
Etiology:
-Idiopathic
-Infections of the CNS: bacterial meningitis, fungal meningitis, herpes encephalitis
-Structural abnormalities: primary or metastatic CNS tumors, toxoplasmosis, AVM
-CNS inflammatory process: CNS lupus, CNS vasculitis
-Cerebral infarction: more common in embolic stroke
-Acute or preexisting brain injury: trauma, hemorrhage (subarachnoid hemorrhage, subdural hematomas)
-Nonstructural precipitants include: electrolyte abnormalities (hyponatremia, hypocalcemia, hypoglycemia), uremia, liver failure, hypoxia, fever (mostly in children), medication (alcohol withdrawal, illicit drugs, cyclosporine)
History:
-Ask about: biting of tongue, urinary or fecal incontinence, aura, postictal confusion
-Ask about: Prior history of head trauma, stroke, tumor, vascular malformation
-Evaluate for: Sleep deprivation, systemic disease, electrolyte derangements, acute infection, drugs that lower seizure threshold, alcohol use
Types of seizures:
Partial/Focal: involves discrete areas of the cerebral cortex, affects one part of the body (can secondarily generalize
-Simple Partial:
-Clinical presentation: no altered consciousness, present with motor, sensory or psychic symptoms. Post-ictal state can include Todd’s paralysis (transient hemiparesis)
-Complex Partial:
-Clinical presentation: present with transient altered consciousness, unable to respond to verbal or visual commands. Impaired recollection or awareness of ictal phase. Will also have automatisms (lip smacking, chewing, foot shuffling, hand fumbling)
Generalized: both cerebral hemispheres simultaneously are involved
Types of generalized seizures and their clinical presentation:
-Absence (petit-mal):
-sudden, brief stare (10 seconds), lapse of consciousness without loss of postural control, usually in children, ages 4-8 years old. Child can present like he/she is “daydreaming” or has a decline in school, will also have mild automatisms, no post-ictal state
-Tonic/clonic (grand mal):
-tonic phase with contraction of muscles (causing expiratory moan, cyanosis, pooling of secretions, tongue biting) à clonic phase with intermittent relaxing and tensing of muscles
-Atonic:
-sudden loss of postural tone lasting 1-2 seconds, no postictal confusion. Can be dangerous since patient just drops, can have trauma
`-Myoclonic:
-sudden, brief muscle contraction in metabolic disorders, degenerative CNS disease, anoxic brain injury
Evaluation (especially for first time seizure)
-consider syncope, migraine, TIA or psychogenic seizures (often convulsion disorder response to stress) in your differential
-perform a full neurological exam
-obtain electrolyes including sodium, calcium, potassium and BUN/creatinine.
-obtain random blood glucose
-obtain FBP
-obtain a CT scan of head if possible
-if patient has history of HIV à perform lumbar puncture after looking for papilledema
-if patient has meningeal signs (nuchal rigidity, fevers) à perform lumbar puncture
Treatment:
-lower patient to the ground or a flat surface
-protect head to prevent head trauma
-place patient on the side to decrease risk of aspiration
-start oxygen therapy by facemask
-make sure there is nothing in the mouth
-suction the mouth if there are any contents
-give diazepam 10 mg IV immediately if actively seizing
-status epilepticus: if patient continues to seize, can give another dose of diazepam à if seizing continues, give phenytoin à if seizing continues, give Phenobarbital, consider intubation
-for chronic medications, please see below
-remember that when giving phenytoin to control seizures, you have to give a loading dose of 1 gram then 300 mg OD after that
Ideal Medications:
| Seizure type | 1st line drug | 2nd line drug |
| Absence (petit-mal) | Ethosuximide | Valproic acid |
| Myoclonic | Valproic acid or clonazepam | Ethosuximide |
| Tonic-clonic (grand mal), simple or complex partial | Phenytoin | Primidone or Phenobarbital |
At Bugando, diazepam, phenytoin, phenobarbital and carbamazepime are primarily available.
Case 1
A 30 year old female with history of HIV (CD4 count is unknown) is brought in to Bugando by her family after she has a seizure at her home. They tell you that she was shaking both of her arms and legs and the entire episode lasted about 1 minute. She was confused afterwards for at least 30 minutes. They deny any fevers or chills or chest pain or shortness of breath. The family does tell you that she complained of intermittent headaches for past 2 weeks. She has not taken any medications for her HIV.
On physical exam, she is afebrile, PR 90 BP 120/70. She is minimally responsive. She is pale. Her pupils are equal and reactive. Fundoscopic exam reveals papilledema. Her heart, lung and abdominal exam are normal. She is moving all four extremities spontaneously and her reflexes are normal. She is unable to cooperate with full neurological exam.
1. What is your differential diagnosis for her seizure?
-viral meningitis, fungal meningitis, toxoplasmosis, CNS lymphoma, other primary CNS lesions
2. What kind of seizure is the family most likely describing?
-grand mal (tonic-clonic)
3. What laboratory evaluation and imaging do you want to order?
-FBP, sodium, calcium, potassium, RBG, creatinine, lumbar puncture, CT brain
4. What is the single most important diagnostic tool as this point?
-CT brain
As you examine the patient, she starts to have another seizure. Both of her arms and legs start shaking?
5. What would you like to do immediately?
-lower patient to the ground or a flat surface, , place patient on her side, make sure nothing is in the mouth,suction mouth if any contents, start oxygen therapy by face mask, suction the mouth, give diazepam 10 mg IV
6. Would you like to start anticonvulsive medication? If yes, which one?
-yes, start phenytoin à give a loading dose of 1 g, then start 300 mg OD
The patient stops seizing. You transfer her to the ICU. She has no more seizures overnight. The next day her FBP returns with leucopenia and anemia. Her creatinine, sodium, calcium and potassium are normal. Her RBG is 6.5. You send her for a CT scan of the brain which shows multiple ring enhancing lesions.
7. What is the most likely etiology of her seizures?
-toxoplasmosis
8. What treatment would you like to give?
-clotrimaxazole
Case 2
A 20 year old male is brought to the clinic by his relatives for several episodes of “shaking” movements. His family reports that over the past 6 months he has had attacks of shaking that initially involve his right arm and leg and then progress to involve his whole body. The episodes last less than a minute. He is typically is confused for about an hour after these episodes. No fever. He takes no medications. Upon further questioning, his family reports that urinary incontinence and tongue biting is associated with these episodes. On physical exam, T 36.4 PR 70 BP 110/80. He is alert and oriented. His fundoscopic, cardiovascular, respiratory, abdominal and neurologic exams are all normal.
1. What is your differential diagnosis?
-epilepsy, CNS tumor, viral infection, vasculitis
2. What type of seizures is the family describing?
-partial complex seizure that generalizes to a grand mal (tonic clonic)
3. What investigations would you like to perform?
-FBP, RBG, ESR, creatinine, sodium, CT scan of the brain (with contrast if available)
His FBP, ESR, RBG, creatinine and sodium are all normal. CT scan of the brain shows no intracranial abnormalities.
4. What is the most likely diagnosis?
-epilepsy
5. What treatment would you like to start?
-phenytoin
6. How would you like to counsel the patient and his family?
-he should not drive or operate any heavy machinery, you should counsel his family that when he has a seizure to place him on a flat surface on his side to prevent aspiration and protect his head to prevent head trauma
One month later you see the patient in the clinic. His family reports that is still having episodes of seizures.
6. What would you like to do next?
-increase dose of phenytoin to 300 mg BD
One month later you see the patient in the clinic again. He reports that he has not had any more seizures since his last clinic visit.
7. How will you counsel him?
-he should continue the current dose of phenytoin and follow up in the clinic regularly every few months, if he begins to have more seizures again he should return to the clinic for medication adjustments and/or further investigations
-if he remains seizure-free for at least 1 year, then he begin to drive and use heavy machinery again however there is still a risk
