Approach to a first unprovoked seizure (pediatrics): Clinical sciences

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Introduction0:00–0:34

Seizures are paroxysmal events caused by abnormal neuronal activity in the brain, and they are considered unprovoked if no acute precipitant can be identified.
Seizures present with a wide variety of manifestations, including focal or generalized motor activity and altered awareness.
Unprovoked seizures can be categorized as either isolated unprovoked seizures or as epilepsy, which can be further classified as distinct syndromes with onset during infancy, childhood, or adolescence.
If a pediatric patient presents with a chief concern suggesting a first unprovoked seizure, start with an ABCDE assessment.

Unstable Patient0:34–1:31

If the patient is unstable, first stabilize the airway, breathing, and circulation, and you may even need to intubate the patient.
Next, obtain IV access, and consider starting IV fluids. Begin continuous vital sign monitoring, including blood pressure, heart rate, and oxygen saturation.
Provide supplemental oxygen if needed, and administer an anti-seizure medication if the seizure lasts longer than 5 minutes.
Now here’s a clinical pearl! A convulsive seizure lasting longer than 5 minutes is considered status epilepticus.
This neurologic emergency requires prompt administration of benzodiazepines, followed by anti-seizure medications like fosphenytoin or phenobarbital.
Once stabilized, a patient with status epilepticus requires further diagnostic evaluation! Okay, let’s go back to the ABCDE and look at stable patients.

Stable Patient1:31–4:51

First, obtain a focused history and physical exam, and consider ordering labs, such as a CMP and blood or urine toxicology screening.
Caregivers typically report an episode of focal or generalized motor activity that could be described as tonic, which involves increased tone or rigidity; clonic, which consists of fast, rhythmic contractions; myoclonic, which is a shock-like muscle contraction; atonic, which is characterized by muscle flaccidity; or tonic-clonic, which starts with stiffening of the whole body followed by rhythmic jerks.
Some patients also experience impaired consciousness or unresponsiveness during the seizure. Verbal patients might describe an aura, which is a sensory experience like flashing lights, that precedes the seizure.
History will reveal no previous seizures and no recent head trauma. Physical exam findings will include no signs suggesting a central nervous system infection, such as meningeal signs or neck stiffness, and no signs of increased intracranial pressure, such as papilledema.
If your patient presents soon after the seizure has resolved, they might exhibit signs indicating a postictal state, such as drowsiness, decreased awareness, or confusion.
Some might demonstrate Todd paresis or paralysis, which is temporary weakness or paralysis of one side of the body following a seizure.
If labs were ordered, results typically reveal normal electrolytes and glucose, as well as a negative toxicology screen.
With these findings, consider an unprovoked seizure. Here’s a high-yield fact!
Some nonepileptic events are commonly mistaken for seizure activity. For example, breath-holding spells during toddlerhood are associated with stiffening and pallor or cyanosis.
Other behaviors and movements that mimic seizures include tics, stereotypies, tantrums, and panic attacks, as well as sleep-related disorders such as parasomnias and periodic leg movements.
You should also consider psychogenic non-epileptic seizures, characterized by sudden, involuntary movements or alterations in consciousness that mimic epileptic seizures, yet they are not caused by abnormal electrical discharges in the brain.
Instead, they’re thought to stem from psychological factors, such as unresolved emotional trauma or stress. Finally, neonatal conditions that can be mistaken for seizures include benign neonatal sleep myoclonus and jitteriness resulting from an immature nervous system.
And another clinical pearl! Febrile seizures commonly occur during acute illness in healthy children between 6 months and 5 years of age.
By definition, febrile seizures are provoked by fever, and affected children have no previous history of unprovoked seizures.
Remember that these children don’t require EEG, neuroimaging, or other diagnostic workup, and treatment involves supportive care and antipyretics, not antiepileptic medications!
Of note, just like sleep deprivation and hyperventilation, fever can trigger seizures in children with epilepsy too! So now you’re considering an unprovoked seizure.

EEG/MRI4:51–5:42

Your next step is to obtain an electroencephalogram, or EEG; with hyperventilation, sleep deprivation, or photic stimulation if needed.
Additionally, consider ordering an MRI of the brain if your patient experienced a focal seizure, or if they have postictal neurologic deficits or prolonged postictal mental status changes.
After you have reviewed the EEG findings, you should assess your patient for epilepsy diagnostic criteria. A diagnosis of epilepsy requires at least two unprovoked seizures more than 24 hours apart, or EEG findings and a clinical history suggesting that seizures are likely to recur.
If criteria are not met, then diagnose an isolated unprovoked seizure. However, if criteria are met, you can diagnose epilepsy.

Epilepsy5:42–6:03

Next, assess the age of onset, to evaluate your patient for the presence of an epilepsy syndrome. Pediatric epilepsy syndromes are characterized by distinct seizure types and triggers, characteristic EEG findings, and typical age of onset.

Infancy6:03–6:15

First, let’s discuss unprovoked seizures that begin during infancy. In this case, you’ll need to assess your patient’s development.
For infants with normal development, consider self-limited neonatal epilepsy. This condition usually presents during the first week of life with focal clonic or tonic motor activity, and in some cases, apnea and cyanosis.

Normal development6:15–7:09

Most infants demonstrate normal development, and the exam and EEG findings are typically normal. This presentation generally indicates benign neonatal seizures, also known as the “fifth day fits”.
Keep this clinical pearl in mind though! If an ill-appearing neonate presents with seizures, consider underlying conditions that provoke seizures, such as hypoglycemia or hypocalcemia; infections like HSV or bacterial sepsis; or even withdrawal from substances like opioids.
Neonatal seizures can appear very subtle, so be alert for fine or unusual movements, as neonates usually don’t present with generalized tonic-clonic activity.

Developmental delay/regression7:09–8:02

What about infants with developmental delay or regression? In this case, consider infantile spasms.
Infants with this condition have seizures characterized by sudden stiffening, often with the knees pulling upward and the body bending forward.
Spasms are brief and usually occur in clusters. Caregivers often mistake infantile spasms for colic or gastroesophageal reflux, since the manifestations appear similar.
Infants usually have global developmental delay, and physical exam can be normal initially, although most patients subsequently demonstrate motor and cognitive impairments.
You'll likely see the characteristic EEG finding of hypsarrhythmia, which is a high-voltage, chaotic pattern of slow spike-and-waves.
With these findings, diagnose infantile spasms, which are called “West Syndrome” if they co-occur with developmental delay and hypsarrhythmia.
Now let’s switch gears and discuss epilepsy syndromes with onset during childhood. In this case, your next step is to assess the child’s development.

Childhood8:02–8:13

If development is normal, consider self-limited epilepsy with centrotemporal spikes or SeLECTS; as well as childhood absence epilepsy.

Normal development8:13–8:23

First up is SeLECTS. These children experience seizures with preserved awareness, just after falling asleep or prior to waking.

SeLECTS8:23–9:12

Seizures are usually focal tonic or clonic, and can be associated with twitching or paresthesias of one side of the lower face and tongue, as well as drooling, dysarthria, and ipsilateral hand twitching.
Some patients may experience secondarily generalized seizures during sleep. Physical exam findings are usually normal, and EEG will demonstrate focal or multifocal centrotemporal spikes during sleep.
These findings confirm the diagnosis of SeLECTS, also called benign childhood epilepsy with centrotemporal spikes, or BECTS; as well as benign rolandic epilepsy.
This self-limited condition generally resolves by adolescence. Next up is childhood absence epilepsy.

Childhood absence epilepsy9:12–9:59

Affected children experience brief staring episodes during which they become unresponsive and appear to be “daydreaming”.
Because of that, some kids are mistakenly diagnosed with ADHD or presumed inattentiveness in the classroom. During the episodes, patients may also demonstrate automatisms like eyelid fluttering or lip smacking.
After the seizure, children return to normal functioning and have no postictal period. Most children with this condition have normal development and normal physical exam findings.
EEG classically demonstrates 3-Hertz spike-and-wave discharges triggered by hyperventilation, are pathognomonic of childhood absence epilepsy.
Treatment of choice is ethosuximide.( Now let’s switch our focus to children with developmental delay or regression. In this case, consider Lennox-Gastaut syndrome.

Developmental delay/regression9:59–10:41

These children typically develop seizures before 5 years of age, with moderate-to-severe developmental delay preceding seizure onset that becomes progressively worse with time.
Patients experience tonic seizures, plus one or more other seizure types, especially during sleep. Physical exam will typically reveal a cognitively impaired child who may have hyperreflexia and spasticity.
EEG classically demonstrates slow spike-and-wave activity less than 2.5 Hertz, and generalized paroxysmal fast activity during sleep.
These findings confirm Lennox-Gastaut syndrome. Finally, let’s discuss seizures with onset in adolescence, which should make you consider juvenile myoclonic epilepsy, or JME.

JME10:41–11:52

This condition typically begins during early adolescence in patients who are otherwise healthy and developing normally. Patients commonly experience myoclonic seizures upon awakening in the early morning that are triggered by sleep deprivation; additionally, some develop generalized tonic-clonic seizures.
Physical exam findings are usually normal, and EEG classically demonstrates fast, generalized spike-and-wave discharges and epileptiform discharges that are triggered by light stimulation.
These findings are diagnostic of juvenile myoclonic epilepsy, which is treated with valproic acid. One last clinical pearl!
Temporal lobe epilepsy is a focal epilepsy that can begin in late childhood, adolescence, or adulthood. Affected patients can have auditory or olfactory auras, as well as focal impaired awareness seizures, which can manifest with symptoms like staring, lip smacking, impaired speech, and posturing.
These seizures can also progress to generalized tonic-clonic seizures. Alright, as a quick recap… When a child presents with a first unprovoked seizure, obtain an EEG and consider an MRI of the brain.

Review11:52–12:35

Then assess the epilepsy diagnostic criteria, and if the criteria are met, begin an evaluation for pediatric epilepsy syndromes by assessing the age of onset and developmental history.
For infants with normal development, consider benign neonatal seizures and for those with developmental delay or regression, consider infantile spasms.
In children with normal development, consider absence epilepsy and SeLECTS, and Lennox-Gastaut in the case of developmental abnormalities.
Finally, for seizures with onset in adolescence, consider juvenile myoclonic epilepsy. Finally for seizures with onset in
Approach to a first unprovoked seizure (pediatrics): Video | Osmosis