Childhood Absence Epilepsy
Guidance for primary care clinicians diagnosing and managing children with childhood absence epilepsy
Childhood absence epilepsy (CAE) is a form of genetically determined, generalized epilepsy that is characterized by absence seizures and, in 10% of cases, generalized tonic-clonic seizures. In CAE, absence seizures start between 4–12 years of age, have a peak occurrence at 6–7 years, and occur many times a day. CAE accounts for 10–15% of childhood epilepsy and is one of the genetic generalized epilepsies.
Children with CAE have higher rates of behavioral, social, and educational problems, and a third of the children with CAE present with attention deficit disorder. [Glauser: 2010] In addition to attention deficit disorder, inattentiveness may be due to ongoing absence seizures or to the side effects of antiseizure medications.
Key Points
Daydreaming vs. absence seizures
Since a diagnosis of absence epilepsy generally results in 2 years of
treatment with an antiseizure medication, it is important to have the correct
diagnosis. Families and teachers of children with absence epilepsy almost always
note an interruption of the child’s activity during the event. Children with absence
epilepsy don't usually respond to the triad of touch, voice, and eye contact when
someone tries to stop the seizure.
Uncontrolled seizures
If the child is not responding to the antiseizure medication, refer
to a pediatric neurologist to determine if the child has a different epilepsy
syndrome and needs changes in treatment.
Signals for increasing medication
Declining school performance may signal a need for an increased
antiseizure medication dose in a child already being treated for absence
seizures.
Treating absence seizures
Three antiseizure medications have been well-studied in CAE:
ethosuximide, valproate, and lamotrigine. Ethosuximide does not prevent generalized
tonic-clonic seizures. If a child with absence seizures also has generalized
tonic-clonic seizures, consider valproate instead of ethosuximide. Lamotrigine is
considered second-line therapy for absence seizures but may be helpful when there
are other seizure types. [Kanner: 2018]
Medications that may increase absence seizures
Carbamazepine and gabapentin may increase absence seizures.
Role of the pediatric clinician
The
primary care clinician can diagnose and manage most children with absence seizures
who are developing typically and have a normal physical exam without neurologic
consultation.
Practice Guidelines
Hirsch E, French J, Scheffer IE, Bogacz A, Alsaadi T, Sperling MR, Abdulla F, Zuberi SM, Trinka E, Specchio N, Somerville
E, Samia P, Riney K, Nabbout R, Jain S, Wilmshurst JM, Auvin S, Wiebe S, Perucca E, Moshé SL, Tinuper P, Wirrell EC.
ILAE definition of the Idiopathic Generalized Epilepsy Syndromes: Position statement by the ILAE Task Force on Nosology and
Definitions.
Epilepsia.
2022;63(6):1475-1499.
PubMed abstract
Diagnosis
Presentations
- Staring, sometimes blinking, eyes may begin to roll back
- Lasts 2–20 seconds but usually about 10 seconds
- Abruptly interrupts activity (such as drinking from a cup or speaking)
- Unaware of their surroundings (e.g., not responsive to being called by name)
- Many a day, sometimes up to 100
- No warning - seizures begin and end suddenly
- Often evoked by hyperventilation - this is a good provocative test in the clinic
Diagnostic Criteria
Inclusion Criteria:
- Age at onset is between 4-12 years, with a peak at 6-7 years
- Normal neurologic state and development
- Absence seizures are brief (4-20 seconds, rarely longer) and frequent (tens per day) with abrupt and severe impairment (loss) of consciousness. Automatisms are frequent, but they have no significance in the diagnosis.
- An EEG shows 3 Hz spike and wave or polyspike and wave discharges during a clinical absence seizure. The EEG background is usually normal; interictal brief generalized spike and wave discharges can be seen, especially during sleep.
- Seizures other than typical absence seizures, such as generalized tonic-clonic seizures or myoclonic jerks
- Eyelid myoclonia, perioral myoclonia, rhythmic massive limb jerking, and single or arrhythmic myoclonic jerks of the head, trunk, or limbs; however, mild myoclonic elements of the eyes, eyebrows, and eyelids may be featured, particularly in the first 3 seconds of the absence seizure
- Mild or no impairment of consciousness during the interictal 3- to 4-Hz discharges
- Visual (photic) and other sensory precipitation of clinical seizures
Screening & Diagnostic Testing
Laboratory Testing
If the child is to be started on valproic acid or ethosuximide, include liver function tests (LFTs) and complete blood count (CBC) with differential to establish baseline levels for later comparison.
Imaging
In a child with typical absence epilepsy (characteristic EEG, clinical history, and normal development and exam), neuroimaging is usually not necessary. [Gaillard: 2009]
Other Testing
During an absence seizure, the EEG shows 3-Hz spike and wave discharges (often frontally dominant) that have an abrupt beginning and ending. Background activity is usually normal in children with CAE. Two minutes of hyperventilation, usually performed during a routine EEG, often induces an absence seizure. After the child has been seizure free on an antiseizure medication for 2 years, an EEG may guide decisions about tapering off the dose.
Genetics & Inheritance
Differential Diagnosis
Daydreaming has no clear start or stop, can be interrupted, has varying durations, occurs less frequently than absence seizures, and occurs in predictable situations (e.g., the classroom).
Focal seizures usually infrequently occur (a few times a week, or a day, compared to many a day) and end with the child feeling confused. Focal seizures are often longer than 20 seconds and may be accompanied by automatisms (lip smacking, teeth grinding, finger movements). Attention deficit disorder does not have discrete episodes of inattentiveness.
Co-occurring Conditions
Prognosis
Without treatment, children can have hundreds of absence seizures a day, which can significantly impair learning and participation in school and family life. Absence seizures can also interrupt normal motor activity and cause injury. For instance, if a child has an absence seizure while walking on a sidewalk, they might not stop at the curb and instead step into traffic.
Remission during adolescence occurs in 65-70% of children with CAE. A lower chance of resolution may be indicated by the presence of generalized seizures, onset of seizures in children <4 years (some may have glucose transporter deficiency caused by a mutation in the SLC2A1 Gene (ILAE), children >8 years, and lack of response to initial therapy. [Tenney: 2013] Recurrence risk after antiepileptic treatment withdrawal in children who have been seizure free for 2 years is 16%. [Ramos-Lizana: 2010]
Treatment & Management
Neurology
Medications
Ethosuximide (Zarontin)
Childhood absence seizures are the only indication for ethosuximide. It is hepatically metabolized; the dose should be adjusted if there is hepatic dysfunction. There are case reports of agranulocytosis and fatal pancytopenia associated with ethosuximide. Check LFTs and CBC with differential before starting and periodically thereafter. Ethosuximide comes in 250 mg capsules and 250mg/5ml syrup.
Valproic acid (Depakote)
Although quite rare in typically developing children over 2 years old, fatal pancreatitis and hepatic failure have been associated with valproate. The incidence of valproate-induced hepatic failure in children <2 years old taking multiple antiseizure medications is 1:500 to 1:800. The risk is lower in older children and adults who are on valproate monotherapy. The risk of hepatic failure is greatest in the first 6 months of use. Valproate is a known teratogen and should be avoided in girls and women of childbearing age, if possible. Check LFTs and CBC with differential before starting and periodically thereafter. Many providers obtain a valproate trough level when the patient is stabilized and repeat labs every 3–6 months throughout treatment. Valproic acid comes in liquid, sprinkle capsules, and tablets (regular and extended-release forms).
Lamotrigine (Lamictal)
Titrate the dose very slowly due to the risk of severe skin reactions (Stevens-Johnson syndrome). If the child is already taking valproic acid, the starting dose is lower and the titration is slower. Adding lamotrigine to valproate, and vice versa, should be done only with the recommendation of a pediatric neurologist. Lamotrigine comes in chewable, dispersible, and regular tablets.
Tapering antiepileptic drugs:
A seizure-free interval of 2 years is recommended before tapering off the antiseizure medication. Some clinicians choose to do an EEG first. If it is normal, consider tapering; if abnormal, consider continuing antiseizure medication therapy for another year.
Learning / Education / Schools
- Neurocognitive defects [Kernan: 2012]
- Loss of learning time due to frequent seizures before treatment
- Poor seizure control even with treatment
- Side effects of antiseizure medications
- Mood disorders
Services & Referrals
Pediatric Neurology
(see NM providers
[5])
Refer for help diagnosing absence seizures that started <4
years old and managing absence seizures that are refractory to ethosuximide,
occur in the setting of developmental delay or intellectual disability, or are
atypical. Depending on the comfort of the medical home provider and family, a
referral may be helpful to confirm the diagnosis, suggest management, and guide
decisions about tapering off an antiepileptic drug. A characteristic EEG is part
of the diagnostic criteria for CAE.
ICD-10 Coding
G40.A, Absence epileptic syndrome
Additional digits indicating the details of diagnosis are needed for billable coding. They can be found at ICD-10 for Absence Epileptic Syndrome (icd10data.com).
Resources
Information & Support
Related Portal Content
Attention-Deficit/Hyperactivity Disorder (ADHD)
Diagnosis and treatment information for primary care clinicians
caring for the child with ADHD.
Depression
Diagnosis and treatment information for primary care clinicians
caring for the child with depression.
Anxiety Disorders
Diagnosis and treatment information for primary care clinicians
caring for the child with anxiety.
Childhood Absence Epilepsy (FAQ)
Answers to questions families often have about caring for their
child with childhood epilepsy.
Attention Deficit Hyperactivity Disorder (ADHD) (FAQ)
Answers to questions families often have about caring for their
child with ADHD
Depression (FAQ)
Answers to questions families often have about caring for their
child with depression.
Anxiety Disorders (FAQ)
Answers to questions families often have about caring for their
child with anxiety.
For Professionals
International League Against Epilepsy
Up-to-date diagnostic criteria, genetics, testing, and differential diagnosis of absence seizures and childhood absence epilepsy.
Childhood Absence Epilepsy (OMIM)
Information about clinical features, diagnosis, management, and molecular and population genetics; Online Mendelian Inheritance
in Man, authored and edited at the McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine
Patient Education
Let's Talk About... EEG (Spanish & English)
Fact sheet about electroencephalographs that measure brain activity; Intermountain Healthcare.
Services for Patients & Families in New Mexico (NM)
Service Categories | # of providers* in: | NM | NW | Other states (3) (show) | | NV | RI | UT |
---|---|---|---|---|---|---|---|---|
Pediatric Neurology | 5 | 5 | 18 | 8 |
For services not listed above, browse our Services categories or search our database.
* number of provider listings may vary by how states categorize services, whether providers are listed by organization or individual, how services are organized in the state, and other factors; Nationwide (NW) providers are generally limited to web-based services, provider locator services, and organizations that serve children from across the nation.
Studies
Childhood Absence Epilepsy (ClinicalTrials.gov)
Studies looking at better understanding, diagnosing, and treating this condition; from the National Library of Medicine.
Helpful Articles
PubMed search for absence epilepsy in children, last 2 years.
Caraballo RH, Dalla Bernardina B.
Idiopathic generalized epilepsies.
Handb Clin Neurol.
2013;111:579-89.
PubMed abstract
Gaillard WD, Chiron C, Helen Cross J, Simon Harvey A, Kuzniecky R, Hertz-Pannier L, Gilbert Vezina L.
Guidelines for imaging infants and children with recent-onset epilepsy.
Epilepsia.
2009.
PubMed abstract
Glauser T, Ben-Menachem E, Bourgeois B, Cnaan A, Guerreiro C, Kälviäinen R, Mattson R, French JA, Perucca E, Tomson T.
Updated ILAE evidence review of antiepileptic drug efficacy and effectiveness as initial monotherapy for epileptic seizures
and syndromes.
Epilepsia.
2013;54(3):551-63.
PubMed abstract
Glauser TA, Cnaan A, Shinnar S, Hirtz DG, Dlugos D, Masur D, Clark PO, Adamson PC.
Ethosuximide, valproic acid, and lamotrigine in childhood absence epilepsy: initial monotherapy outcomes at 12 months.
Epilepsia.
2013;54(1):141-55.
PubMed abstract / Full Text
Mula M, Kanner AM, Schmitz B, Schachter S.
Antiepileptic drugs and suicidality: an expert consensus statement from the Task Force on Therapeutic Strategies of the ILAE
Commission on Neuropsychobiology.
Epilepsia.
2013;54(1):199-203.
PubMed abstract
Sidhu R, Velayudam K, Barnes G.
Pediatric seizures.
Pediatr Rev.
2013;34(8):333-41; 342.
PubMed abstract
Wheless JW, Clarke DF, Carpenter D.
Treatment of pediatric epilepsy: expert opinion, 2005.
J Child Neurol.
2005;20 Suppl 1:S1-56; quiz S59-60.
PubMed abstract
Authors & Reviewers
Author: | Lynne M. Kerr, MD, PhD |
Reviewer: | Denise Morita, MD |
2019: update: Lynne M. Kerr, MD, PhDA; Denise Morita, MDR |
2015: update: Denise Morita, MDR |
2013: first version: Lynne M. Kerr, MD, PhDA |
Page Bibliography
Caraballo RH, Dalla Bernardina B.
Idiopathic generalized epilepsies.
Handb Clin Neurol.
2013;111:579-89.
PubMed abstract
Cerminara C, D'Agati E, Casarelli L, Kaunzinger I, Lange KW, Pitzianti M, Parisi P, Tucha O, Curatolo P.
Attention impairment in childhood absence epilepsy: an impulsivity problem?.
Epilepsy Behav.
2013;27(2):337-41.
PubMed abstract
Gaillard WD, Chiron C, Helen Cross J, Simon Harvey A, Kuzniecky R, Hertz-Pannier L, Gilbert Vezina L.
Guidelines for imaging infants and children with recent-onset epilepsy.
Epilepsia.
2009.
PubMed abstract
Glauser T, Ben-Menachem E, Bourgeois B, Cnaan A, Guerreiro C, Kälviäinen R, Mattson R, French JA, Perucca E, Tomson T.
Updated ILAE evidence review of antiepileptic drug efficacy and effectiveness as initial monotherapy for epileptic seizures
and syndromes.
Epilepsia.
2013;54(3):551-63.
PubMed abstract
Glauser TA, Cnaan A, Shinnar S, Hirtz DG, Dlugos D, Masur D, Clark PO, Adamson PC.
Ethosuximide, valproic acid, and lamotrigine in childhood absence epilepsy: initial monotherapy outcomes at 12 months.
Epilepsia.
2013;54(1):141-55.
PubMed abstract / Full Text
Glauser TA, Cnaan A, Shinnar S, Hirtz DG, Dlugos D, Masur D, Clark PO, Capparelli EV, Adamson PC.
Ethosuximide, valproic acid, and lamotrigine in childhood absence epilepsy.
N Engl J Med.
2010;362(9):790-9.
PubMed abstract / Full Text
Hirsch E, French J, Scheffer IE, Bogacz A, Alsaadi T, Sperling MR, Abdulla F, Zuberi SM, Trinka E, Specchio N, Somerville
E, Samia P, Riney K, Nabbout R, Jain S, Wilmshurst JM, Auvin S, Wiebe S, Perucca E, Moshé SL, Tinuper P, Wirrell EC.
ILAE definition of the Idiopathic Generalized Epilepsy Syndromes: Position statement by the ILAE Task Force on Nosology and
Definitions.
Epilepsia.
2022;63(6):1475-1499.
PubMed abstract
Kanner AM, Ashman E, Gloss D, Harden C, Bourgeois B, Bautista JF, Abou-Khalil B, Burakgazi-Dalkilic E, Park EL, Stern J, Hirtz
D, Nespeca M, Gidal B, Faught E, French J.
Practice guideline update summary: Efficacy and tolerability of the new antiepileptic drugs I: Treatment of new-onset epilepsy:
Report of the American Epilepsy Society and the Guideline Development, Dissemination, and Implementation Subcommittee of the
American Academy of Neurology.
Epilepsy Curr.
2018;18(4):260-268.
PubMed abstract / Full Text
Kernan CL, Asarnow R, Siddarth P, Gurbani S, Lanphier EK, Sankar R, Caplan R.
Neurocognitive profiles in children with epilepsy.
Epilepsia.
2012;53(12):2156-63.
PubMed abstract
Mula M, Kanner AM, Schmitz B, Schachter S.
Antiepileptic drugs and suicidality: an expert consensus statement from the Task Force on Therapeutic Strategies of the ILAE
Commission on Neuropsychobiology.
Epilepsia.
2013;54(1):199-203.
PubMed abstract
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Absence seizures in children.
BMJ Clin Evid.
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PubMed abstract / Full Text
Ramos-Lizana J, Aguirre-Rodríguez J, Aguilera-López P, Cassinello-García E.
Recurrence risk after withdrawal of antiepileptic drugs in children with epilepsy: a prospective study.
Eur J Paediatr Neurol.
2010;14(2):116-24.
PubMed abstract
Rosati A, Ilvento L, Lucenteforte E, Pugi A, Crescioli G, McGreevy KS, Virgili G, Mugelli A, De Masi S, Guerrini R.
Comparative efficacy of antiepileptic drugs in children and adolescents: A network meta-analysis.
Epilepsia.
2018;59(2):297-314.
PubMed abstract
Sidhu R, Velayudam K, Barnes G.
Pediatric seizures.
Pediatr Rev.
2013;34(8):333-41; 342.
PubMed abstract
Tenney JR, Glauser TA.
The current state of absence epilepsy: can we have your attention?.
Epilepsy Curr.
2013;13(3):135-40.
PubMed abstract / Full Text
Valentin A, Hindocha N, Osei-Lah A, Fisniku L, McCormick D, Asherson P, Moran N, Makoff A, Nashef L.
Idiopathic generalized epilepsy with absences: syndrome classification.
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Genetic mechanisms in idiopathic epilepsies.
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PubMed abstract
Wheless JW, Clarke DF, Carpenter D.
Treatment of pediatric epilepsy: expert opinion, 2005.
J Child Neurol.
2005;20 Suppl 1:S1-56; quiz S59-60.
PubMed abstract