First-time seizure

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Background

Seizure Types

Classification is based on the international classification from 1981[1]; More recent terms suggested by the ILAE (International League Against Epilepsy) task Force.[2]

Focal seizures

(Older term: partial seizures)

  • Without impairment in consciousness– (AKA Simple partial seizures)
    • With motor signs (ex. facial twiching or rhythmic ipsilateral extremity movements)
    • With sensory symptoms (ex. tingling or pereiving a certain smell)
    • With autonomic symptoms or signs (ex. tachycardia or diaphoresis)
    • With psychic symptoms (including aura, ex. sense of déjà-vu)
  • With impairment in consciousness - (AKA Complex Partial Seizures--Older terms: temporal lobe or psychomotor seizures)
    • Simple partial onset, followed by impairment of consciousness
    • With impairment of consciousness at onset
    • These seizures may be accompanied by automatism (such as lip smacking and chewing, hand wringing, patting and rubbing)
  • Focal seizures evolving to secondarily generalized seizures
    • Simple partial seizures evolving to generalized seizures
    • Complex partial seizures evolving to generalized seizures
    • Simple partial seizures evolving to complex partial seizures evolving to generalized seizures

Generalized seizures

  • Absence seizures (Older term: petit mal; brief dissociative states without postural changes)
    • Typical absence seizures
    • Atypical absence seizures (last longer and often include more motor involvement)
  • Myoclonic seizure (violent muscle contractions)
  • Clonic seizures (rhythmic jerking)
  • Tonic seizures (stiffening)
  • Tonic–clonic seizures (Older term: grand mal)
  • Atonic seizures (loss of muscle tone -> drop attacks)

SUDEP[3]

  • Sudden Unexpected Death in Epilepsy
  • Generalized tonic-clonic seizure is the major risk factor for SUDEP, and seizure freedom is strongly associated with decreased risk
    • Annual incidence of SUDEP in children is 1 in 4500
    • Incidence in adults is 1 in 1000

Clinical Features

  • Abrupt onset, may be unprovoked
  • Brief duration (typically <2min)
  • AMS
  • Jerking of limbs
  • Postictal drowsiness/confusion (typically lasting <30 minutes)
  • Todd paralysis
  • Lateral tongue biting - 100% specificity
  • Incontinence

Differential Diagnosis

Causes of first-time seizure

Seizure

Diagnosis

Work-up

  • Glucose
  • CBC
  • Chemistry
  • Pregnancy test
  • Utox
  • Head CT
  • LP (if SAH or meningitis/encephalitis is suspected)

Indications for Head CT due to Seizure[4]

  • If patient has returned to a normal baseline:
    1. When feasible, perform a neuroimaging of the brain in the ED on patients with a first-time seizure
    2. Deferred outpatient neuroimaging may be used when reliable follow-up is available

Evaluation

Management

Several states have mandatory DMV reporting requirements

  • No anticonvulsant treatment necessary if patient has[5]:
    • Normal neuro exam
    • No acute or chronic medical comorbidities
    • Normal diagnostic testing (including normal imaging)
    • Normal mental status
  • Treatment generally indicated if seizure due to an identifiable neurologic condition

Disposition

  • Discharge (no need to start antiepileptic[5]) with neuro follow up
  • Risk for recurrent seizure is greatest within the first 2 years after a first seizure (21%-45%)

See Also

External Links

References

  1. Proposal for revised clinical and electroencephalographic classification of epileptic seizures. From the Commission on Classification and Terminology of the International League Against Epilepsy. Epilepsia 1981; 22:489.
  2. Epilepsia 2015; 56:1515-1523.
  3. Harden C et al. American Academy of Neurology and the American Epilepsy Society. Practice guideline summary: Sudden unexpected death in epilepsy incidence rates and risk factors. Neurology April 25, 2017 vol. 88 no. 17 1674-1680.
  4. ACEP Clinical policy: Critical issues in the evaluation and management of adult patients presenting to the emergency department with seizures. Ann Emerg Med 2004; 43:605-625
  5. 5.0 5.1 Krumholz A, et al. Evidence-based guideline: Management of an unprovoked first seizure in adults. Neurology 2015; 84(16):1705-1713.