What is the appropriate workup and management for a patient with new onset seizure?

Workup for New Onset Seizure

The appropriate workup for new onset seizure requires a comprehensive diagnostic approach including essential laboratory tests (glucose, sodium, pregnancy test in women of childbearing age), neuroimaging (MRI preferred over CT), and EEG within 24-48 hours of the seizure. 1

Initial Evaluation

History and Examination

• Focus on:
  • Seizure characteristics (duration, focal vs. generalized, aura)
  • Return to baseline mental status
  • Presence of postictal focal deficits
  • History of trauma, substance use, or medical conditions
  • Current medications
  • Family history of seizures

Essential Laboratory Tests

• Required for all patients:
  • Serum glucose
  • Serum sodium
  • Pregnancy test (women of childbearing age)
• Additional tests based on clinical presentation:
  • Complete metabolic panel (if altered mental status)
  • Toxicology screen (if suspected substance use or altered mental status)
  • CBC, blood cultures, lumbar puncture (if febrile)
  • Antiepileptic drug levels (if on seizure medications)
  • CK levels (after generalized tonic-clonic seizure)
  • Troponin levels (older patients with generalized tonic-clonic seizure)

Neuroimaging

• MRI is preferred over CT for first-time seizures as it's more sensitive for detecting brain abnormalities 1
• Emergent neuroimaging indications:
  • Postictal focal deficit not quickly resolving
  • Failure to return to baseline within several hours
  • Suspected intracranial bleeding
  • History of trauma, malignancy, or immunocompromised state
  • Persistent altered mental status

Electroencephalography (EEG)

• EEG should be performed in all patients with first-time seizures 1
• Ideally performed within 24-48 hours of the seizure
• Helps differentiate seizure types and identify epilepsy syndromes
• May detect epileptiform abnormalities that increase recurrence risk

Management Considerations

Treatment Decisions

• Antiepileptic drug therapy is not routinely indicated after a single unprovoked seizure 2
• Consider starting antiepileptic drugs if:
  • High risk for recurrence (abnormal EEG, structural lesion on imaging)
  • Patient has had multiple seizures (meeting epilepsy definition)
  • Patient preference after discussing risks/benefits

First-line Medications (if treatment indicated)

• Levetiracetam is often preferred due to:
  • Efficacy for both partial and generalized seizures 3
  • Favorable side effect profile
  • Minimal drug interactions
  • Safe in hepatic dysfunction 1

Disposition and Follow-up

Discharge Criteria

• Return to baseline mental status
• Single self-limited seizure with no recurrence
• Normal or non-acute findings on neuroimaging
• Reliable follow-up available
• Responsible adult to observe the patient

Follow-up Requirements

• Neurology referral is essential for all patients with new-onset seizures 1
• Provide seizure precautions and safety measures
• Advise on driving restrictions according to local laws
• Educate about seizure triggers to avoid

Special Considerations

Status Epilepticus

• Seizures lasting >5 minutes require emergency treatment with benzodiazepines 1
• Multiple seizures without return to baseline require emergency intervention

Common Pitfalls to Avoid

• Failing to distinguish seizures from syncope, pseudoseizures, or other mimics
• Overlooking treatable causes (hypoglycemia, hyponatremia, toxicity, infection)
• Not obtaining appropriate neuroimaging in high-risk patients
• Unnecessary initiation of antiepileptic drugs after a single unprovoked seizure with low recurrence risk
• Inadequate safety counseling regarding driving and activities

By following this structured approach to the evaluation and management of new-onset seizures, clinicians can ensure appropriate diagnosis, treatment, and follow-up while avoiding unnecessary interventions.