| Both sides previous revision Previous revision Next revision | Previous revision |
| content:childhood_absence_epilepsy [2024/03/09 18:44] – [Childhood Absence Epilepsy] biju.hameed@gmail.com | content:childhood_absence_epilepsy [2024/03/19 17:06] (current) – [Differentiating between CAE and JAE] biju.hameed@gmail.com |
|---|
| ====== Childhood Absence Epilepsy ====== | ====== Childhood Absence Epilepsy ====== |
| {{tag>childhood_absence_epilepsy CCNA1H}} | {{tag>childhood_absence_epilepsy CCNA1H}} |
| Childhood absence epilepsy (CAE) is an age-dependent, idiopathic form of generalised epilepsy characterised by multiple absence seizures per day, as well as bilateral, symmetrical, and synchronous discharges of 3-Hz generalised spike and waves (GSW) in the electroencephalogram. CAE makes for 2% to 10% of all paediatric epilepsies and 8-15% of school-aged childhood epilepsies. Seizures occur many times daily and consist of brief staring spells, sometimes with rhythmic eye blinking or motor automatisms, lasting seconds, with immediate return to the baseline level of awareness and activity. Children with CAE develop normally, although attentional deficiencies or other subtle behavioural or cognitive abnormalities may be present at onset. | * Childhood absence epilepsy (CAE) is an age-dependent, idiopathic form of generalised epilepsy (IGE) characterised by multiple absence seizures per day, as well as bilateral, symmetrical, and synchronous discharges of 3-Hz generalised spike and waves (GSW) in the electroencephalogram. |
| | * The 2017 International League Against Epilepsy (ILAE)classification suggested that the term IGE could be reserved for the four syndromes including childhood absence epilepsy (CAE), juvenile absence epilepsy (JAE), [[juvenile myoclonic epilepsy]] (JME), and epilepsy with generalized tonic–clonic seizures alone (GTCA)[(:cite:pmid28276062>{{pmid>long:28276062}})]. |
| | * CAE makes for 2% to 10% of all paediatric epilepsies and 8-15% of school-aged childhood epilepsies. Seizures occur many times daily and consist of brief staring spells, sometimes with rhythmic eye blinking or motor automatisms, lasting seconds, with immediate return to the baseline level of awareness and activity. Children with CAE develop normally, although attentional deficiencies or other subtle behavioural or cognitive abnormalities may be present at onset. |
| ===== Investigations ===== | ===== Investigations ===== |
| <imgcaption absenceeeg|A typical absence seizure on electroencephalogram, characterized by 3 Hz generalized spike wave discharges, with abrupt onset and offset, lasting several second>{{ :content:absences.png?400x106}}</imgcaption> | <imgcaption absenceeeg|A typical absence seizure on electroencephalogram, characterized by 3 Hz generalized spike wave discharges, with abrupt onset and offset, lasting several second>{{ :content:absences.png?400x106}}</imgcaption> |
| * Because VPA slows down the metabolism of LTG by blocking liver enzymes, titration of LTG starts at an even lower dose, moves more slowly, and hits a lower target in a person who is also taking VPA than in a person who is not taking any other medication. | * Because VPA slows down the metabolism of LTG by blocking liver enzymes, titration of LTG starts at an even lower dose, moves more slowly, and hits a lower target in a person who is also taking VPA than in a person who is not taking any other medication. |
| * There are important cognitive, behavioural, and psychological problems associated with CAE that need to be identified early and dealt with. Anxiety and attention deficit hyperactivity disorder (ADHD) are significantly associated with CAE[(:cite:pmid18557780>{{pmid>long:18557780}})]. | * There are important cognitive, behavioural, and psychological problems associated with CAE that need to be identified early and dealt with. Anxiety and attention deficit hyperactivity disorder (ADHD) are significantly associated with CAE[(:cite:pmid18557780>{{pmid>long:18557780}})]. |
| ===== Treatment resistant CAE ===== | |
| * If first- and second-line drugs don't work, clobazam might be worth a try. However, there isn't much literature on its use in treatment-resistant CAE | |
| * The ketogenic diet has also been used successfully in children with treatment-resistant CAE[(:cite:pmid20647578>{{pmid>long:20647578}})] | |
| * There is mixed evidence about how well levetiracetam works for children absence epilepsy. Some reports say it works pretty well[(:cite:pmid21320119>{{pmid>long:21320119}})][(:cite:pmid18808424>{{pmid>long:18808424}})], while another report says it makes absence seizures worse[(:cite:pmid21680209>{{pmid>long:21680209}})]. | |
| |
| ===== Differentiating between CAE and JAE ===== | ===== Differentiating between CAE and JAE ===== |
| | Abbreviations: ADHD, attention-deficit/hyperactivity disorder; CAE, childhood absence epilepsy; EEG, electroencephalogram; IGE, idiopathic generalized epilepsy; IPS, intermittent photic stimulation; JAE, juvenile absence epilepsy; OIRDA, occipital intermittent rhythmic delta activity. a Disorganized discharges are defined as either brief (less than 1 sec and and transient interruptions in ictal rhythm or waveforms of different frequency or morphology during the ictal rhythm. ||| | | Abbreviations: ADHD, attention-deficit/hyperactivity disorder; CAE, childhood absence epilepsy; EEG, electroencephalogram; IGE, idiopathic generalized epilepsy; IPS, intermittent photic stimulation; JAE, juvenile absence epilepsy; OIRDA, occipital intermittent rhythmic delta activity. a Disorganized discharges are defined as either brief (less than 1 sec and and transient interruptions in ictal rhythm or waveforms of different frequency or morphology during the ictal rhythm. ||| |
| </tabcaption> | </tabcaption> |
| | |
| | While reporting an EEG the following terms are suggested, whenever appropriate: spike-and-slow-wave complex, 3 c/s spike-and-slow-wave complex, sharp-and-slow wave complex. Use of the term "absences" is discouraged when describing EEG patterns. |
| ===== Pathophysiology ===== | ===== Pathophysiology ===== |
| * Absence seizures result from disruptions in thalamocortical rhythms via T-type calcium channel dysfunction. | * Absence seizures result from disruptions in thalamocortical rhythms via T-type calcium channel dysfunction. |
| * The [[https://www.genecards.org/cgi-bin/carddisp.pl?gene=CACNA1H|CACNA1H]] missense variant (rs61734410/P640L), though not a CAE disease-causing variant, has been reported to be more often associated with ETX non-response in the CAE trial, supported by in vitro neurophysiologic studies[(:cite:pmid28165634>{{pmid>long:28165634}})]. | * The [[https://www.genecards.org/cgi-bin/carddisp.pl?gene=CACNA1H|CACNA1H]] missense variant (rs61734410/P640L), though not a CAE disease-causing variant, has been reported to be more often associated with ETX non-response in the CAE trial, supported by in vitro neurophysiologic studies[(:cite:pmid28165634>{{pmid>long:28165634}})]. |
| * Several recurring Copy Number Variations (CNVs), such as 15q11.2, 15q13.3, and 16p13.11 microdeletion[(:cite:pmid19843651>{{pmid>long:19843651}})], contribute to a complicated inheritance pattern seen in CAE.A chromosomal microarray should be requested for children with substantial learning difficulties due to the higher probability of pathogenic CNVs | * Several recurring Copy Number Variations (CNVs), such as 15q11.2, 15q13.3, and 16p13.11 microdeletion[(:cite:pmid19843651>{{pmid>long:19843651}})], contribute to a complicated inheritance pattern seen in CAE.A chromosomal microarray should be requested for children with substantial learning difficulties due to the higher probability of pathogenic CNVs |
| | |
| | ===== Treatment resistant CAE ===== |
| | * If first- and second-line drugs don't work, clobazam might be worth a try. However, there isn't much literature on its use in treatment-resistant CAE |
| | * The ketogenic diet has also been used successfully in children with treatment-resistant CAE[(:cite:pmid20647578>{{pmid>long:20647578}})] |
| | * There is mixed evidence about how well levetiracetam works for children absence epilepsy. Some reports say it works pretty well[(:cite:pmid21320119>{{pmid>long:21320119}})][(:cite:pmid18808424>{{pmid>long:18808424}})], while another report says it makes absence seizures worse[(:cite:pmid21680209>{{pmid>long:21680209}})]. |
| | |
| ===== References ===== | ===== References ===== |
| |
