Management of New-Onset Seizure in a 15-Year-Old Male
For a 15-year-old male with new onset seizure or seizure-like activity, the best course of action is to obtain an MRI of the brain as the primary imaging study, refer to neurology, and avoid prophylactic anticonvulsant medication until a definitive diagnosis is established. 1
Initial Assessment and Diagnostic Workup
Imaging
- MRI is the imaging study of choice for new-onset seizures in the non-emergent setting 1
- Should include coronal T1-weighted imaging, high-resolution volume acquisition, and coronal T2 and fluid-attenuated inversion recovery sequences
- More sensitive than CT for detecting lesions in orbitofrontal and medial temporal regions, and small cortical lesions
- CT should only be used in emergent situations when rapid assessment is needed or when there's a need for ready access to the patient during scanning
Laboratory Testing
- Essential laboratory tests include:
- Serum glucose
- Serum sodium
- Complete metabolic panel if altered mental status is present
- Toxicology screen if substance use is suspected
- CBC, blood cultures, lumbar puncture if fever is present
- Consider antiepileptic drug levels if relevant
Referral to Neurology
Timing and Importance
- Referral to neurology is essential as recommended in the guidelines 1, 2
- The neurological evaluation should include:
- EEG to identify epilepsy syndromes and predict recurrence risk
- Classification of seizure type to identify the region of brain where seizure originated
- Classification of epilepsy syndrome when possible
Treatment Considerations
Medication Management
- Do not initiate prophylactic anticonvulsant medications after a single seizure 1
- Evidence suggests possible harm with negative effects on neurological recovery
- A single, self-limiting seizure occurring at the onset or within 24 hours should not be treated with long-term anticonvulsant medications
When to Consider Treatment
- Treatment with antiepileptic drugs should be considered only if:
- Patient has recurrent seizures (defined as epilepsy)
- High risk for recurrence is present (history of brain insult, epileptiform abnormalities on EEG, or structural lesion on MRI) 3
- When a second seizure could have devastating psychosocial effects
Medication Selection (if treatment becomes necessary)
- If treatment is eventually needed, levetiracetam may be considered:
- For adolescents, dosing starts at 20 mg/kg/day in 2 divided doses 4
- Increased every 2 weeks by increments of 20 mg/kg to recommended daily dose of 60 mg/kg
- Well-tolerated in pediatric populations
Monitoring and Follow-up
Seizure Monitoring
- Monitor for recurrent seizure activity during routine monitoring of vital signs and neurological status 1
- Consider enhanced or increased seizure/EEG monitoring as adolescents are an at-risk population 1
Patient Education
- Provide education about:
- Seizure precautions and safety measures
- Driving restrictions (relevant as patient approaches driving age)
- Seizure triggers to avoid
- When to seek emergency care
Common Pitfalls to Avoid
Premature diagnosis of epilepsy: Approximately 8-10% of the population will experience a seizure during their lifetime, but only 2-3% develop epilepsy 5
Unnecessary treatment: Avoid prescribing anticonvulsants after a single unprovoked seizure unless specific risk factors for recurrence are present 2
Inadequate diagnostic workup: Failure to complete appropriate imaging and EEG can result in undefined etiology in up to 62% of cases 2
Missing non-seizure causes: Many conditions can mimic seizures, including syncope, migraine, cerebrovascular disease, movement disorders, and sleep disorders 3
Overlooking treatable causes: Seizures may be provoked by reversible factors such as metabolic derangements, medications, or acute illness 6
By following this approach, you can ensure appropriate evaluation and management of this adolescent patient with new-onset seizure, while avoiding unnecessary treatment and ensuring proper specialist follow-up.