Every pediatrician faces the challenge of determining whether a child who had a paroxysmal event had a seizure. Therefore, it is important for the general pediatrician to have a good understanding of the diagnosis and management of a child’s first seizure.
Epidemiology and Definition of Seizures and Epilepsy
Seizures are one of the most common neurologic disorders in children. Approximately 120,000 children in the United States are seen annually for new-onset seizure.1 One percent of children will experience an afebrile seizure by 14 years of age, and up to 5% of children will have a febrile seizure by 6 years of age. More than 50% of people with epilepsy had their first seizure during childhood or adolescence.2 Thus, an increased awareness among all pediatricians of the initial management of a child’s first seizure is critically important.
The International League Against Epilepsy (ILAE) defines a seizure as a clinical manifestation of excessive discharge in a population of hyperexcitable neurons in the brain. The clinical manifestation consists of a sudden and transitory phenomenon that may include altered consciousness or motor, sensory, autonomic, or psychic events perceived either by the patient or by an observer.
Epilepsy is defined by the ILAE as a disorder of the brain characterized by an enduring predisposition to generate seizures and by the neurobiological, cognitive, psychological, and social consequences of this condition. This definition notes the importance of caring for the whole child in the treatment of epilepsy. Children with epilepsy may also experience comorbid behavioral problems, impaired neurocognitive function, issues with memory, school difficulties, negative self-esteem, and reduced quality of life. An enriched environment and treatment strategies that address not only the child’s epilepsy, but also the child’s social, emotional, and cognitive needs have been associated with overall better quality of life, less seizure recurrence, and decreased long-term consequences.3
The Clinical Encounter
The pediatrician is asked to provide answers to many critical questions when faced with a paroxysmal event. These include:
Was the child’s event a seizure?
Was the seizure provoked or unprovoked?
What is the diagnostic and prognostic value of EEG?
Is neuroimaging warranted?
Does routine blood work yield valuable information?
What is the likelihood of recurrence?
Is it appropriate to initiate therapy with antiepileptic drugs (AED) in a first seizure?
The answers to these important questions are discussed below.
Differential Diagnosis of a Paroxysmal Event
When presented with a paroxysmal event, the first question to be answered is whether the event was indeed a seizure. The child’s history helps distinguish between epileptic and non-epileptic events more than an EEG. Many children with epilepsy have normal findings on EEG, and an abnormal EEG is not necessary to make the diagnosis of a seizure. Therefore, a careful history is the first step for primary care physicians to identify whether an event was a seizure. The history should include details of the setting in which the event occurred, the sequence of events leading up to and during the event, and the child’s behavior following the event.4
No single sign is specific for a seizure. Seizures are often sudden, momentary alterations in behavior that occur without warning and may be followed by a prolonged postictal period of drowsiness, sleep, confusion, or weakness. Tongue biting, incontinence, and postictal state, although not specific, often suggests a seizure.
The physician presented with a paroxysmal event rarely witnesses the event. It is often helpful to obtain the description of the event directly from the observer, asking the observer to show what happened either by acting out or videotaping the event. Observation of the child’s spells is often helpful in establishing the right diagnosis.
Table 1 reviews the critical elements of the history that may help the physician decide whether the paroxysmal event was a seizure.
Critical Historical Elements in a Child with Possible First Seizure
Risk factors for development of epilepsy include abnormal development, including any developmental delays or apparent regression; focal neurologic findings; and family history of epilepsy.5
Common non-epileptic events to consider include syncope, complex motor tics, stereotyped behaviors, gastroesophageal reflux, breath-holding spells, migraines, stroke/transient ischemic attack, and conversion disorder (non-epileptic or so-called “pseudo-seizures”). Some of the more difficult-to-differentiate diagnoses are reviewed in Table 2.
Common Non-Epileptic Events in the Differential Diagnosis of Paroxysmal Event
Evaluation of a New-Onset Seizure
If the history is consistent with the diagnosis of seizure, the next question to be answered is whether the seizure was provoked or unprovoked. Initial evaluation and management should determine a cause of seizure and seek to rule out potential provocation, such as fever, central nervous system (CNS) infection, traumatic brain injury, CNS tumor, cerebrovascular disease, drug withdrawal or ingestion, or other toxic/metabolic insults. Provoked seizures require treatment of both the seizure and the underlying cause. The risk of subsequent epilepsy is low (< 1% to 3%) in seizures provoked by reversible metabolic or toxic insults.5 The risk of seizure recurrence is higher (> 10%) in spells provoked by mechanisms associated with brain damage (ie stroke, brain abscess).6,7
Febrile seizures are the most prevalent form of provoked seizure in early life, affecting 5% of infants and young children.8 Simple febrile seizures are defined as seizures that occur with fever in the absence of CNS infection, known epilepsy, or metabolic disorders in a healthy and developmentally appropriate child. The simple, generalized febrile convulsion lasts less than 15 minutes and occurs once in a 24-hour period. Complex febrile seizures are prolonged (ie, more than 15 minutes) and have focal neurologic features or recur during a 24-hour period.
Ninety percent of febrile seizures occur before the age of 3 years, with a peak between 18 months to 2 years of age. Simple febrile seizures in children with normal development are associated with a 1% to 2% chance of epilepsy in later life compared with 0.5% to 1% in the general population.8 The most important risk factors of subsequent epilepsy are an abnormal neurologic exam, a family history of epilepsy, history of complex febrile seizures, and an abnormal developmental state. The risk of later epilepsy can be almost 50% when such risk factors are present.8
Simple febrile seizures do not warrant treatment, except to treat the fever and its underlying cause. There is no evidence of later CNS damage in children who have a single episode of simple febrile seizure. Antipyretics are not effective in preventing recurrent febrile seizures and do not decrease the chance of developing epilepsy later in life. Routine blood cell counts, metabolic panels, EEG, or imaging studies are not cost-effective or diagnostic in a child with simple febrile seizures and are not recommended. A child presenting with complex febrile seizures may suggest underlying epilepsy “uncovered by fever” that warrants additional evaluation. Febrile status epilepticus may indicate a more serious disease process, such as meningitis or encephalitis, and also warrant further diagnostic investigation.
Pediatrician’s Evaluation of First Unprovoked Seizure
A detailed history is paramount to determine whether a paroxysmal event is consistent with an unprovoked seizure. An unprovoked episodic event marked by loss of consciousness, sustained involuntary movements, disturbances in sensorium, an evolution in time with a plausible neuro-anatomical correlate, and post-ictal state suggests a seizure.
Most children presenting with a first unprovoked seizure will have a normal general and neurologic exam. The skin exam is important, as several neurocutaneous disorders (eg, tuberous sclerosis) associated with epilepsy have skin findings (eg, hypopigmented macules) early in childhood. Genetic assessment is warranted if dysmorphism is noted. An enlarged liver or palpable spleen on abdominal exam may be consistent with an underlying inborn error of metabolism or storage disease.
The American Academy of Neurology and Child Neurology Society consensus statement recommends an EEG as a standard of care for a child presenting with a first afebrile seizure. What is the diagnostic and prognostic value of EEG? The EEG is useful to evaluate risk of seizure recurrence, to determine whether a seizure is focal or generalized, to screen for focal abnormalities and possible need for MRI, to identify epilepsy syndrome classification, to guide choice of antiepileptics, and to aid in prognosis.2,9
The decision as to whether neuroimaging is warranted in a first unprovoked seizure should be based on the child’s age, seizure type, and risk factors for a focal/structural abnormality. Urgent neuroimaging is recommended in children with risk factors such as head trauma, focal neurologic deficits, or a history of malignancy, as well as in children younger than 1 year of age.10 MRI is more sensitive in detecting temporal lobe pathology, dysplastic lesions, and brain malformations and is preferred over CT, except when intracranial bleeding or acute increased intracranial pressure is suspected.11,12
Approximately 10% of children with a new-onset focal seizure have an abnormality on MRI. Urgent neuroimaging is unwarranted for a well-appearing child older than the age of 1 year with a normal neurologic examination and without risk factors. However, a non-emergent MRI is often later indicated if an epilepsy diagnosis is made to assess future risk of seizures and to guide therapeutic management.11
Does routine blood work yield valuable information? Laboratory studies including metabolic panels, blood count, and toxicology are performed only when clinically indicated. Routine blood work is not cost-effective and should not be universally obtained.4
Lumbar puncture is performed when clinically indicated in children with a history or assessment suggestive of CNS infection, such as meningitis or meningoencephalitis. Strongly consider lumbar puncture if the child is younger than 6 months old, or in any child who does not return to baseline mental status.12,13
Figure 1 summarizes the recommended diagnostic steps in children with a first seizure.
A summary of the recommended diagnostic steps in children with a first seizure. CNS = central nervous system. EEG = electroencephalogram.
After the first unprovoked seizure, it is important to determine the likelihood of recurrence, as well as whether antiepileptic drugs are required.
The therapeutic approach to a first unprovoked seizure in children remains controversial. Years ago, nearly all children who presented with first unprovoked seizure were started on AED therapy. However, clinical experience and research in children have shown that these medications must be utilized with caution, as their side-effect profile is not benign; they are a well-described cause of lethargy, dizziness, ataxia, headache, Stevens-Johnson syndrome, megaloblastic anemia, and liver toxicity.
These potential AED complications have changed the approach to treatment to one in which each child who presents with a first seizure receives a risk-benefit assessment to weigh the benefits of treatment, including lowering seizure recurrence and decreasing long-term consequences of epilepsy, against the adverse effects of AED treatment. Most pediatric neurologists monitor a child with a first unprovoked seizure if the child has a normal neurologic exam, negative family history of epilepsy, normal neuroimaging, normal EEG, and overall normal development. Treatment is often deferred until there are clearly recurrent seizures.
The overall seizure recurrence rate following the first unprovoked seizure is 23% to 71% at 3 years if left untreated. Treatment decreases this risk by half.13–15 The risk is highest within the first year following the first seizure. Seizure recurrence is more likely if there is an abnormal EEG, remote symptomatic etiology (eg, prior CNS insult), status epilepticus, nocturnal seizures, previous febrile seizures, or Todd’s paresis.5,9,12–14
If the child’s presentation is suspicious for an epilepsy syndrome, referral to a specialist in neurology or epilepsy is warranted for epilepsy syndrome classification and discussion of treatment strategies and prognosis with the family. Diagnosis of electroclinical epilepsy syndromes is based on the age of seizure onset, the child’s development and examination, seizure type, and EEG pattern. The diagnosis of epilepsy is made after a child has had two or more unprovoked seizures.3 An AED is often recommended after the second seizure because the risk of a third seizure rises to 70% to 90%.9,16 Appropriate AED is selected according to seizure type (focal versus generalized), underlying etiology, and epilepsy syndrome.
The evidence reviewed here highlights the initial steps of the diagnosis and management of a child’s first seizure by the general pediatrician. A careful and detailed history and physical examination are critical to diagnosing a first seizure. In children presenting with febrile seizure, the pediatrician should educate family members on recurrence and prognosis. Treatment is aimed at treating the fever and the cause of fever. An EEG should be obtained in every child presenting with first unprovoked seizure to evaluate seizure type, risk of recurrence, and to guide treatment. An MRI is more sensitive than a CT for the detection of structural abnormalities and is recommended to assess the risk of seizure recurrence and guide therapeutic management in children with abnormal development, focal neurological examination, a history of malignancy, and in children younger than 1 year of age.
The decision to initiate AED treatment requires the assessment of the risk of recurrence weighed against the risk of well-known complications associated with these drugs and is usually deferred until there are clearly recurrent seizures. Optimal choice of AED (or no AED) is possible when a specific diagnosis of epilepsy syndrome is made based on the child’s age, development, seizure type, and EEG characteristics. Consider expert consultation with a specialist in neurology or epilepsy when epilepsy syndrome is suspected, as the family will need education about the diagnosis of epilepsy, prognosis, and the different approaches to treatment.
- Hauser WA, Beghi E. First seizure definitions and worldwide incidence and mortality. Epilepsia. 2008;49(Suppl 1):8–12. doi:10.1111/j.1528-1167.2008.01443.x [CrossRef]
- Wiebe S, Téllez-Zenteno JF, Shapiro M. An evidence-based approach to the first seizure. Epilepsia. 2008;49(Suppl 1):50–57. doi:10.1111/j.1528-1167.2008.01451.x [CrossRef]
- ILAE Commission report. Restrictions for children with epilepsy. Commission of Pediatrics of the ILAE. International League AgainstEpilepsy. Epilepsia. 1997;38(9):1054–1056.
- Perrig S, Jallon P. Is the first seizure truly epileptic?Epilepsia. 2008;49(Suppl 1):2–7. doi:10.1111/j.1528-1167.2008.01442.x [CrossRef]
- Pohlmann-Eden B, Beghi E, Camfield C, Camfield P. The first seizure and its management in adults and children. BMJ. 2006;332(7537):339–342. doi:10.1136/bmj.332.7537.339 [CrossRef]
- Annegers JF, Grabow JD, Groover RV, et al. Seizures after head trauma: a population study. Neurology. 1980;30(7 Pt 1):683–689. doi:10.1212/WNL.30.7.683 [CrossRef]
- Annegers JR, Hauser WA, Beghi E, Nicolosi A, Kurland LT. The risk of seizures after encephalitis and meningitis. Neurology. 1988;38(9):1407–1410. doi:10.1212/WNL.38.9.1407 [CrossRef]
- Annegers JF, Hauser WA, Shirts SB, Kurland LT. Factors prognostic of unprovoked seizures after febrile convulsions. N Engl J Med. 1987;316(9):493–498. doi:10.1056/NEJM198702263160901 [CrossRef]
- Shinnar S, Berg AT, O’Dell C, et al. Predictors of multiple seizures in a cohort of children prospectively followed from the time of their first unprovoked seizure. Ann Neurol. 2000;48(2):140–147. doi:10.1002/1531-8249(200008)48:2<140::AID-ANA2>3.0.CO;2-Y [CrossRef]
- Sharma S, Riviello JJ, Harper MB, Baskin MN. The role of emergent neuroimaging in children with new-onset afebrile seizures. Pediatrics. 2003;111(1):1–5. doi:10.1542/peds.111.1.1 [CrossRef]
- Gaillard WD, Chiron C, Cross JH, et al. Guidelines for imaging infants and children with recent-onset epilepsy. Epilepsia. 2009;50(9):2147–2153. doi:10.1111/j.1528-1167.2009.02075.x [CrossRef]
- Beghi E. The management of a first seizure. General conclusions and recommendations. Epilepsia. 2008;49(Suppl1):58–61. doi:10.1111/j.1528-1167.2008.01452.x [CrossRef]
- Hirtz D, Berg A, Bettis D, et al. Practice parameter: treatment of the child with a first unprovoked seizure. Neurology. 2003;60(2):166–175. doi:10.1212/01.WNL.0000033622.27961.B6 [CrossRef]
- Chadwick DW. The treatment of the first seizure: the benefits. Epilepsia. 2008;49(Suppl. 1):26–28. doi:10.1111/j.1528-1167.2008.01446.x [CrossRef]
- Marson A, Jacoby A, Johnson A, et al. Immediate versus deferred antiepileptic drug treatment for early epilepsy and single seizures: a randomized controlled trial. Lancet. 2005;365(9476):2007–2013. doi:10.1016/S0140-6736(05)66694-9 [CrossRef]
- Camfield PR, Camfield CS, Dooley JM, et al. Epilepsy after a first unprovoked seizure in childhood. Neurology. 1985;35(11):1657–1660. doi:10.1212/WNL.35.11.1657 [CrossRef]
Critical Historical Elements in a Child with Possible First Seizure
Setting in which spell occurred.
Child’s behavior prior to, during, and after the spell.
Description of the spell by the observer.
The duration and frequency of the spell.
Family history of epilepsy, febrile seizures, genetic disorders.
A neurodevelopmental history.
Psychosocial history including stressors, use of prescription or illicit drugs, alcohol use.
Medical history including birth history, prior central nervous system insults or infections, trauma.
Common Non-Epileptic Events in the Differential Diagnosis of Paroxysmal Event
Irregular respiratory pattern: Often seen in newborn and premature infants. Periodic breathing is almost never seizure unless associated with tonic movements, eye deviation, or tachycardia.
Breath-holding spells: Involuntary pause in breathing precipitated by frustration, anger, fright, or painful event. Not associated with postictal state. Most commonly seen between 6 to 18 months of age.
Gastroesophageal reflux: Infants may stiffen, appear limp, look startled, or arch in response to reflux.
Infantile self-stimulatory behavior: form of self-gratification. Rhythmic hip flexion and pelvic movements accompanied by dystonic-like posturing of the neck, back, and extremities. Consciousness is preserved. Typically suppressible with distraction.
Staring spell: Behavioral staring differs from absence in that children who daydream will respond to stimuli.
Syncope: Preceded by premonition of light-headedness, dizziness, facial pallor, or sweating; the child may feel “faint” or “dizzy” prior to loss of consciousness.
Tics: Sudden, brief, intermittent, involuntary or semi-voluntary movements or sounds; child is often able to suppress tics.
Stereotopies: Repetitive, self-stimulating behaviors often seen in children with autism spectrum disorder. They are not seizures and do not warrant anticonvulsant therapy.
Non-epileptic seizure: Form of conversion disorder or dissociative reaction to overwhelmingly stressful life situation. Long-term video EEG capture of the typical event with lack of EEG correlate is diagnostic.