Residency · Residency · Medicine-Pediatrics

Seizures and Epilepsy Across Ages

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Alright, you're looking a bit tired, intern. Just imagine this scenario: It's 3 AM, and you've just admitted a newborn having rhythmic jerking in one arm, subtle mouth movements – classic neonatal seizure. You also have a previously healthy teenager in the Emergency Department who just had their first grand mal, what we call a generalized tonic-clonic seizure, while playing video games. Two very different patients, but both presenting with seizures, and your brain is probably flashing "seizure protocol" for both. This is where your med-peds brain really shines because, while the core phenomenon is similar – abnormal electrical activity in the brain – almost everything else about them is different.

For that tiny neonate, your first thought is probably something like hypoxic-ischemic encephalopathy from birth trauma or a metabolic derangement like low blood sugar. You’d be looking at different labs and considering different initial treatments compared to the teenager. With the teen, maybe they just stayed up too late, or perhaps it’s something more chronic like juvenile myoclonic epilepsy, which often kicks in around that age. You wouldn't immediately jump to a brain tumor in the newborn, but it's certainly on your radar for the older adult who might present with new-onset seizures. The key takeaway here is that the 'why' behind a seizure, and therefore the 'what to do next,' changes dramatically with age.

So, as you walk into each patient's room, you're not just seeing "a seizure." You're seeing a newborn with potential birth-related brain injury, or an adolescent possibly facing a lifelong diagnosis, or even an elderly patient whose seizure might be the first sign of a stroke. Your diagnostic workup and initial treatment choices will pivot based on their age group because the most common culprits, the preferred anti-seizure medications (ASMs), and even the long-term prognosis are all age-dependent. Keep that in mind, and you'll navigate these complex cases much more effectively, even at 3 AM.

Introduction

Seizures represent one of the most common neurologic emergencies encountered by medicine-pediatrics physicians. The spectrum of epilepsy spans from neonatal seizures to new-onset epilepsy in the elderly, with age-specific etiologies, classification systems, and treatment strategies. A med-peds clinician must understand these differences to provide seamless care across the lifespan.

Definitions and Classification

ILAE 2017 Classification

Focal onset: Arising from networks limited to one hemisphere. Generalized onset: Engaging bilateral networks from onset. Unknown onset: Insufficient information to classify. Focal to bilateral tonic-clonic: Previously called secondary generalization.

Key Terminology

Seizure: A transient occurrence of signs/symptoms due to abnormal excessive or synchronous neuronal activity. Epilepsy: Defined by any of the following: two unprovoked seizures >24 hours apart, one unprovoked seizure with >60% recurrence risk, or a diagnosed epilepsy syndrome. Status epilepticus: Continuous seizure activity lasting >5 minutes or recurrent seizures without return to baseline.

Age-Specific Etiologies

Neonatal Period (0-28 days)

Hypoxic-ischemic encephalopathy (most common); Intracranial hemorrhage; Metabolic disturbances (hypoglycemia, hypocalcemia); Neonatal infections (meningitis, encephalitis); Inborn errors of metabolism (pyridoxine-dependent epilepsy).

Infancy and Early Childhood (1 month - 5 years)

Febrile seizures (most common; simple vs. complex); Genetic epilepsy syndromes (Dravet syndrome, infantile spasms); CNS infections; Structural abnormalities (cortical dysplasia).

School Age and Adolescence (6-18 years)

Childhood absence epilepsy (peak 4-8 years); Juvenile myoclonic epilepsy (peak 12-18 years); Benign epilepsy with centrotemporal spikes; Autoimmune encephalitis.

Adults and Elderly

Traumatic brain injury; Cerebrovascular disease (most common cause in adults >35); Brain tumors; Neurodegenerative diseases; Alcohol withdrawal seizures.

Diagnostic Workup

First Seizure Evaluation

Detailed history: semiology, duration, preceding aura, postictal state; EEG: Standard, sleep-deprived, or continuous monitoring. Neuroimaging: MRI preferred over CT (except in acute setting) Laboratory studies: glucose, electrolytes, toxicology screen; Lumbar puncture when infection is suspected.

Pediatric-Specific Considerations

Developmental history and regression assessment. Genetic testing for suspected epilepsy syndromes. Metabolic workup for neonatal and infantile seizures.

Adult-Specific Considerations

Cardiac evaluation to exclude syncope. Alcohol and substance use assessment. Occupational and driving implications.

Treatment Principles

When to Start Antiseizure Medications (ASMs)

After a second unprovoked seizure (standard recommendation) After a first seizure with high recurrence risk (abnormal EEG, structural lesion) Immediate treatment for status epilepticus.

First-Line ASMs by Age and Seizure Type

Special Considerations

Valproate: Avoid in women of childbearing potential (teratogenicity) Carbamazepine/phenytoin: May worsen generalized epilepsy. Ketogenic diet: Effective in refractory pediatric epilepsy. Surgical evaluation for drug-resistant epilepsy (failed two adequate ASM trials)

Transition of Care

Adolescents with epilepsy need structured transition to adult neurology. Address medication adherence, driving laws, reproductive counseling. Update seizure action plans for school, work, and independent living.

Clinical Pearls

Febrile seizures do not require chronic ASM therapy; parental education is paramount. Juvenile myoclonic epilepsy typically requires lifelong treatment due to high relapse rates. Always consider autoimmune encephalitis (anti-NMDA receptor) in young patients with new-onset seizures and psychiatric symptoms. In the elderly, levetiracetam and lamotrigine are preferred due to fewer drug interactions. Med-peds physicians are uniquely positioned to manage epilepsy transitions from childhood through adulthood.

References

1. Fisher RS, Cross JH, French JA, et al. Operational classification of seizure types by the International League Against Epilepsy. Epilepsia. 2017;58(4):522-530.
2. Kwan P, Arzimanoglou A, Berg AT, et al. Definition of drug resistant epilepsy: Consensus proposal by the ad hoc Task Force of the ILAE Commission on Therapeutic Strategies. Epilepsia. 2010;51(6):1069-1077.
3. Shellhaas RA, Wusthoff CJ, Tsuchida TN, et al. Profile of neonatal epilepsies: Characteristics of a prospective US cohort. Neurology. 2017;89(9):893-899.
4. Subcommittee on Febrile Seizures, American Academy of Pediatrics. Neurodiagnostic evaluation of the child with a simple febrile seizure. Pediatrics. 2011;127(2):389-394.

For the intern

At 3am, your priorities are acute seizure management and ruling out life-threatening causes. Initiate benzodiazepines for active seizures, check fingerstick glucose and vital signs, and consider lumbar puncture if fever or meningismus is present. Order stat labs (electrolytes, toxicology) and neuroimaging if this is a first seizure with focal findings or trauma. Most chronic epilepsy management—medication adjustments, EEG scheduling, genetic testing—can wait until morning rounds when you can review the history thoroughly and involve neurology.

Common pitfalls

• Assuming all seizures need chronic medication: Simple febrile seizures and single provoked seizures (alcohol withdrawal, severe hyponatremia) typically do not require antiseizure medications after the acute event resolves.

• Using valproate in women of childbearing age: This medication carries significant teratogenicity risk. Choose lamotrigine or levetiracetam instead, and document counseling about contraception.

• Missing autoimmune encephalitis: New psychiatric symptoms with seizures in adolescents or young adults warrant consideration of anti-NMDA receptor encephalitis, especially if they're not responding to standard treatments.

• Overlooking medication adherence: In teenagers transitioning to adult care, non-adherence is the most common cause of breakthrough seizures. Address this directly rather than reflexively increasing doses or adding medications.

Make it stick

Picture this: It's 2 AM, and you're admitting a 4-year-old with their third unprovoked generalized tonic-clonic seizure, eyes rolling back, entire body stiffening and jerking. Simultaneously, your pager goes off: an 82-year-old with new-onset focal seizures, presenting as left arm twitching and speech arrest. As the resident, you're juggling two vastly different patients, but both need immediate attention. You stabilize the child, order a stat EEG and MRI, and start broad-spectrum antiseizure medication, suspecting a genetic syndrome. For the elderly patient, you consider stroke, tumor, or even an autoimmune cause, and you carefully select an ASM with minimal drug interactions given their comorbidities.

If you remember one thing

Seizures across the lifespan have age-specific etiologies and treatment considerations; a unified approach by a medicine-pediatrics physician ensures optimal, continuous care from infancy to old age. Always consider the patient's age when evaluating seizures, as this will guide your differential diagnosis, diagnostic workup, and choice of antiseizure medication.

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