Overview
Definition:
A first-time seizure is a single episode of transient neurological dysfunction caused by abnormal, synchronous, excessive neuronal discharge in the brain
It represents a significant clinical event requiring thorough evaluation to determine etiology, risk of recurrence, and appropriate management, including decisions on inpatient vs
outpatient workup.
Epidemiology:
The incidence of first-time seizures in children varies with age, with a bimodal peak in infancy and adolescence
Approximately 0.5-1% of children experience a seizure by the age of 15 years
Febrile seizures are the most common type in young children, while unprovoked seizures are more common in older children and adolescents.
Clinical Significance:
The initial presentation of a seizure necessitates prompt and accurate assessment to differentiate between benign and serious underlying etiologies
The decision for inpatient versus outpatient management significantly impacts resource utilization, patient anxiety, and diagnostic efficiency, directly affecting patient care and management pathways
DNB and NEET SS candidates must understand these decision-making processes.
Clinical Presentation
Symptoms:
Witnessed convulsive movements of limbs
Altered consciousness or responsiveness
Staring spells or brief behavioral changes
Sensory disturbances
Autonomic symptoms like pallor or flushing
Postictal confusion or lethargy.
Signs:
Focal neurological deficits (transient or persistent)
Signs of trauma from the seizure
Fever
Meningeal signs
Cardiac arrhythmias
Respiratory distress
Funduscopic examination for papilledema.
Diagnostic Criteria:
Diagnosis is primarily clinical, based on detailed history and witnessed events
Electroencephalography (EEG) and neuroimaging are crucial for further classification and etiology determination, but not for the initial diagnosis of a seizure itself
The International League Against Epilepsy (ILAE) classification is used for seizure types.
Diagnostic Approach
History Taking:
Detailed description of the event: onset, duration, motor activity, associated symptoms, preceding aura, postictal state
Triggers: fever, sleep deprivation, photic stimulation, illness
Family history of seizures or epilepsy
Developmental history
Medications and toxic exposures
Red flags: prolonged postictal state, focal neurological deficits, status epilepticus, new onset in an infant or elderly child, associated systemic illness.
Physical Examination:
Complete neurological examination including assessment of cranial nerves, motor strength, sensation, reflexes, coordination, and gait
Examination for signs of trauma, infection (meningitis, encephalitis), or underlying systemic disease
Funduscopic examination
Cardiorespiratory examination.
Investigations:
Laboratory tests: Complete blood count (CBC) to assess for infection
Electrolytes (sodium, calcium, magnesium, glucose) to rule out metabolic derangements
Liver function tests and renal function tests if indicated
Blood ammonia if concern for inborn error of metabolism
Toxicology screen if suspected
Neuroimaging: Magnetic resonance imaging (MRI) of the brain is preferred for structural evaluation, especially for focal seizures or if neuroimaging is indicated
Computed tomography (CT) scan may be used in emergent settings or if MRI is contraindicated/unavailable
Electroencephalogram (EEG): A standard EEG is crucial to assess for interictal epileptiform discharges, although a normal EEG does not rule out epilepsy
Continuous EEG (cEEG) may be indicated for prolonged or suspected non-convulsive seizures.
Differential Diagnosis:
Syncope (vasovagal, cardiogenic)
Breath-holding spells
Psychogenic non-epileptic seizures (PNES)
Migraine with aura
Tics
Benign sleep myoclonus
Movement disorders
Shivering
Vasculitis
Todd's paralysis.
Management Decision Inpatient Vs Outpatient
Inpatient Evaluation Indications:
Status epilepticus or prolonged seizure
Status post prolonged postictal state
Concerns for acute central nervous system infection (meningitis, encephalitis)
New onset seizure in an infant <1 year old
Focal neurological deficit
Significant trauma during the seizure
Suspected status epilepticus
Underlying significant comorbidities or medical instability
Need for rapid diagnostic workup including urgent EEG or MRI.
Outpatient Evaluation Indications:
First unprovoked generalized convulsive seizure in a child >1 year old with normal neurological examination and no concerning features
Febrile seizures in a child who is otherwise well
Clear history suggestive of benign event (e.g., simple febrile seizure)
No immediate need for aggressive workup
Stable patient with reliable follow-up.
Risk Stratification For Recurrence:
Risk factors for recurrence include: abnormal EEG, abnormal neuroimaging, history of prior neurological insult (stroke, head trauma), focal seizure type, developmental delay, and sleep deprivation
Children with one or more risk factors have a significantly higher recurrence risk.
Treatment Considerations:
Antiepileptic drug (AED) therapy is typically initiated after a second unprovoked seizure
For a first seizure, AEDs are usually reserved for high-risk patients (e.g., those with status epilepticus, prolonged postictal state, significant EEG abnormalities, or focal neurological deficits), or if the etiology is life-threatening and requires immediate seizure control
The choice of AED depends on seizure type, age, comorbidities, and potential side effects.
Management
Initial Management:
Ensure airway, breathing, and circulation (ABC)
Protect from injury
Administer oxygen if hypoxic
For prolonged seizures (>5 minutes) or status epilepticus: administer benzodiazepines (e.g., IV lorazepam, IM midazolam) as first-line treatment
Follow with second-line agents if seizures persist (e.g., IV fosphenytoin, levetiracetam, valproic acid).
Medical Management:
Decision to start long-term antiepileptic drug (AED) therapy is based on recurrence risk and patient/family preferences
Common AEDs for children include levetiracetam, valproic acid, carbamazepine, oxcarbazepine, and lamotrigine
Dosing is age and weight-based, with specific protocols and monitoring for drug levels and side effects
For febrile seizures, antipyretics are used, and prophylactic AEDs are generally not recommended unless there are specific risk factors for recurrence
For specific etiologies like infections, treatment of the underlying cause is paramount.
Surgical Management:
Surgical intervention is considered for refractory epilepsy that is focal and clearly localized to a resectable area of the brain, after failure of multiple AEDs
This is a complex decision usually managed by pediatric neurosurgery teams and is rarely indicated for a first-time seizure unless an acute surgical lesion is identified.
Supportive Care:
Close monitoring of vital signs, neurological status, and seizure activity
Fluid and electrolyte balance management
Nutritional support if indicated
Education of patient and family regarding seizure precautions, medication adherence, and emergency management
Referral to epilepsy centers for complex cases.
Prognosis
Factors Affecting Prognosis:
The prognosis after a first-time seizure depends on the underlying etiology and the risk of recurrence
Children with a single unprovoked seizure and no risk factors have a favorable prognosis with a low recurrence rate
Etiologies like benign febrile seizures generally have an excellent prognosis
Conditions associated with brain injury, stroke, tumors, or severe infections carry a poorer prognosis for seizure control and neurological outcome.
Outcomes:
Most children who experience a first-time seizure do not develop chronic epilepsy
For those who do, the majority can achieve seizure control with appropriate AED therapy
However, a subset of children may have intractable epilepsy, leading to developmental delays, cognitive impairment, and psychosocial challenges.
Follow Up:
Follow-up is essential to monitor for seizure recurrence, assess adherence to AEDs, manage side effects, and evaluate neurodevelopmental progress
Regular clinical and EEG evaluations are crucial
The decision to discontinue AEDs is typically made after a prolonged seizure-free period (e.g., 2-5 years) and is individualized based on seizure type, age, and risk of recurrence.
Key Points
Exam Focus:
Differentiating benign from concerning first seizures
Indications for inpatient vs
outpatient workup
Risk factors for seizure recurrence
Management of status epilepticus
Initial AED choices for pediatric seizures
Understanding the role of EEG and MRI in first seizure evaluation.
Clinical Pearls:
Always obtain a detailed history and witness account if possible
this is paramount
A normal neurological exam and normal EEG do not completely rule out epilepsy
Do not routinely start AEDs after a single unprovoked seizure unless high-risk features are present or indicated by guidelines
Educate parents on seizure safety and when to seek emergency care.
Common Mistakes:
Over-reliance on EEG/MRI without thorough clinical evaluation
Premature initiation of AEDs after a single seizure without risk stratification
Inadequate management of status epilepticus
Failure to consider serious underlying etiologies such as infection or structural lesions
Insufficient patient and family education.