What key elements should be included in the history taking for an infant presenting with seizures?

History Taking for Infant Seizures

When evaluating an infant with seizures, your history must systematically identify the underlying etiology to guide treatment decisions that directly impact neurodevelopmental outcomes, as treating all seizures (both electrographic and electroclinical) is associated with better neurodevelopmental outcomes and reduced likelihood of later epilepsy 1.

Critical Etiology-Specific History Elements

The presumed etiology fundamentally determines treatment approach and prognosis 1. Structure your history to identify these specific categories:

Perinatal/Birth History

• Hypoxic-ischemic encephalopathy (HIE): Most common cause (25.1% of neonatal seizures) 1

  • Apgar scores at 1,5, and 10 minutes
  • Need for resuscitation at birth
  • Umbilical cord blood gases
  • Whether therapeutic hypothermia was initiated
  • Timing of seizure onset relative to birth (typically within 24-48 hours for HIE)

• Stroke or hemorrhage:

  • Difficult delivery, instrumentation use
  • Focal neurological signs
  • Asymmetric movements during seizure

Family History - CRITICAL for Treatment Selection

• Seizures in immediate family members (parents, siblings)
  • If positive family history suggests channelopathy (KCNQ2/KCNQ3 genes), this completely changes first-line treatment from phenobarbital to sodium channel blockers (phenytoin or carbamazepine) 1
  • Age of onset in affected family members
  • Whether seizures resolved spontaneously (suggests benign familial neonatal epilepsy)

Seizure Characterization

Document with extreme specificity:

• Exact description of movements: tonic, clonic, myoclonic, focal versus generalized
• Duration: Status epilepticus (>30 minutes) requires different management
• Frequency and clustering pattern
• Lateralization: Focal features suggest structural lesion or stroke
• Eye deviation or gaze preference
• Autonomic signs: apnea, color change, heart rate changes
• Level of consciousness between events
• Video recording availability: Essential for diagnosis confirmation 2

Preceding Illness/Triggers

• Fever: Temperature, duration, source
  • Febrile illness preceding seizure may suggest cryptogenic NORSE (new onset refractory status epilepticus), which carries extremely poor prognosis 3
• Recent infections: Respiratory, gastrointestinal, rash
• Trauma: Even minor head trauma
• Feeding history changes: Improperly prepared formula can cause hyponatremic seizures 4

Cardiac History

• Known cardiac disorders: If present, levetiracetam is preferred second-line agent over phenytoin 1
• Cyanotic episodes
• Murmurs or known structural heart disease

Metabolic Red Flags

• Vitamin B6-dependent epilepsy features 1:
  • Seizures starting in utero or immediately after birth
  • Refractory to standard antiseizure medications
  • Requires pyridoxine trial if suspected or if seizures don't respond to second-line therapy
• Poor feeding, vomiting, lethargy (suggests inborn error of metabolism)
• Abnormal odor
• Developmental regression

Clinical Features Suggesting Channelopathy

Even without family history, certain EEG or clinical patterns suggest channelopathy 1:

• Seizures in otherwise well-appearing infant
• Specific seizure semiology (migration pattern)
• Normal neuroimaging
• These patients require sodium channel blockers, not phenobarbital

Outcome-Critical Historical Points

Prognostic Factors for Epilepsy Development

Document these risk factors as they predict 14.1% epilepsy risk and 14.6% cerebral palsy risk in survivors 5:

• History of febrile seizures
• Status epilepticus occurrence
• Family history of epilepsy
• Developmental delay
• Abnormal neurological examination

Response to Stimuli

In critically ill infants with refractory seizures, document whether seizures are stimulus-induced (auditory, visual, tactile triggers), as this indicates an extreme hyperexcitability state with very poor prognosis 3.

Common Pitfalls to Avoid

1. Missing subclinical seizures: Most neonatal seizures have no clinical manifestations (electrographic-only) 1. History alone is insufficient—EEG monitoring is mandatory.

2. Assuming all movements are seizures: Jitteriness, startle responses, and benign neonatal sleep myoclonus are commonly mistaken for seizures 1.

3. Failing to ask about family history: This single element changes first-line treatment from phenobarbital to sodium channel blockers 1.

4. Not documenting cardiac history: Phenytoin is contraindicated in cardiac disorders; levetiracetam becomes preferred 1.

5. Missing vitamin B6 deficiency: Always consider in refractory cases, as pyridoxine trial is indicated when seizures don't respond to second-line therapy 1.

Parent Communication Requirements

The 2023 ILAE guidelines mandate that parents must be informed about 1:

• Nature of neonatal seizures
• Treatment options with efficacy data
• Potential adverse events of antiseizure medications
• Probable duration of treatment
• That most acute provoked seizures allow medication discontinuation before discharge home (regardless of MRI or EEG abnormalities) 1