関: absence epilepsy、absence seizure、juvenile absence epilepsy、petit mal epilepsy

WordNet

failure to be present
the occurrence of an abrupt, transient loss or impairment of consciousness (which is not subsequently remembered), sometimes with light twitching, fluttering eyelids, etc.; common in petit mal epilepsy (同)absence_seizure
the state of being absent; "he was surprised by the absence of any explanation"
the time interval during which something or somebody is away; "he visited during my absence"
the state of a child between infancy and adolescence (同)puerility
the time of persons life when they are a child
a disorder of the central nervous system characterized by loss of consciousness and convulsions

PrepTutorEJDIC

〈U〉〈C〉『るす』,不在;『欠席』;不在期間;(…を)欠席すること《+『from』+『名』》 / 〈U〉(…が)『ないこと』,(…の)欠如(lacking)《+『of』+『名』》
『幼時』,子供時代
てんかん

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2016/02/15 04:24:43」(JST)

wiki en

Childhood absence epilepsy (CAE), also known as pyknolepsy, is an idiopathic generalized epilepsy which occurs in otherwise normal children. The age of onset is between 4–10 years with peak age between 5–7 years. Children have absence seizures which although brief (~4–20 seconds), they occur frequently, sometimes in the hundreds per day. The absence seizures of CAE involve abrupt and severe impairment of consciousness. Mild automatisms are frequent, but major motor involvement early in the course excludes this diagnosis. The EEG demonstrates characteristic "typical 3Hz spike-wave" discharges. Prognosis is excellent in well-defined cases of CAE with most patients "growing out" of their epilepsy.^[1]

Signs and symptoms

(Video of Absence Seizure)

Causes

CAE is a complex polygenic disorder. Particularly in the Han Chinese population there is association between mutations in CACNA1H and CAE. These mutations cause increased channel activity and associated increased neuronal excitability. Seizures are believed to originate in the thalamus, where there is an abundance of T-type calcium channels such as those encoded by CACNA1H.

Pathophysiology

There are currently 20 mutations in CACNA1H associated with CAE. These mutations are likely not wholly causative and should instead be thought of as giving susceptibility. This is particularly true since some groups have found no connection between CAE and CACNA1H mutations.^[2] Many of the CACNA1H mutations have a measurable effect on channel kinetics, including activation time constant and voltage dependence, deactivation time constant, and inactivation time constant and voltage dependence (summarized in Table 1). Many of these mutations should lead to neuronal excitability, though others may lead to hypoexcitability. These predictions are due to mathematical modeling and may differ from what will occur in real neurons where other proteins, some of which may interact with CACNA1H, are present.

Along with mutations in CACNA1H, two mutations in the gene encoding a GABA_A receptor γ subunit are also associated with a CAE like phenotype that also overlaps with generalized epilepsy with febrile seizures plus type-3. The first of these, R43Q, abolishes benzodiazepine potentiation of GABA induced currents.^[3]^[4] The second associated mutation, C588T has not been further characterized.

**Table 1.** Summary of mutations in CACNA1H associated with childhood absence epilepsy
Mutation	Region	Activation		Deactivation	Inactivation		Excitability Prediction	References
Mutation	Region	V₅₀	Tau	Deactivation	V₅₀	Tau	Excitability Prediction	References
F161L	D1S2-3	Unchanged*	Unchanged	Depolarized	Accelerated	Unchanged	Hypoexcitable	^[5]^,^[6]^,^[7]
E282K	D1S5-6	Hyperpolarized	Unchanged	Unchanged	Unchanged	Unchanged	Hypoexcitable	^[5]^,^[6]^,^[7]
P314S	D1-2	?	?	?	?	?	?	^[8]
C456S	D1-2	Hyperpolarized	Accelerated	Unchanged	Unchanged	Unchanged	Hyperexcitable	^[5]^,^[6]^,^[7]
A480T	D1-2	?	Unchanged	?	?	Unchanged	?	^[9]^,^[10]
P492S	D1-2	?	?	?	?	?	?	^[8]^,^[8]
G499S	D1-2	Unchanged	Unchanged	Unchanged	Unchanged	Unchanged	Unchanged	^[5]^,^[7]
P618L	D1-2	?	Accelerated	?	?	Accelerated	?	^[9]^,^[10]
V621fsX654	D1-2	?	?	?	?	?	?	^[9]
P648L	D1-2	Unchanged	Unchanged	Unchanged	Depolarized	Slowed	Hyperexcitable	^[5]^,^[7]
R744Q	D1-2	Unchanged	Unchanged	Unchanged	Unchanged	Unchanged	Unchanged	^[5]^,^[7]
A748V	D1-2	Unchanged	Accelerated	Unchanged	Unchanged	Unchanged	Unchanged	^[5]^,^[7]
G755D	D1-2	?	Unchanged	?	?	Accelerated	?	^[9]^,^[10]
G773D	D1-2	Depolarized	Slowed	Slowed	Depolarized	Slowed	Hyperexcitable	^[5]^,^[7]
G784S	D1-2	Unchanged	Slowed	Unchanged	Unchanged	Unchanged	Unchanged	^[5]^,^[7]
R788C	D1-2	Depolarized	Slowed	Slowed	Unchanged	Slowed	Hyperexcitable	^[7]^,^[8]
G773D + R788C	D1-2	Unchanged	Unchanged	Slowed	Unchanged	Unchanged	Hyperexcitable	^[7]
V831M	D2S2	Unchanged	Hyperpolarized	Slowed	Depolarized	Slowed	Hypoexcitable	^[5]^,^[6]^,^[7]
G848S	D2S2	Unchanged	Unchanged	Slowed	Unchanged	Unchanged	Unchanged	^[5]^,^[7]
D1463N	D2S5-6	Unchanged	Accelerated	Unchanged	Unchanged	Unchanged	Unchanged	^[5]^,^[6]^,^[7]
*	Depending on experimental paradigm

Diagnosis

Diagnosis is made upon history of absence seizures during early childhood and the observation of ~3 Hz spike-and-wave discharges on an EEG.^{[citation needed]}

Management

Epidemiology

Childhood absence epilepsy is a fairly common disorder with a prevalence of 1 in 1000 people.^{[citation needed]} Few of these people will likely have mutations in CACNA1H or GABRG2^{[citation needed]} as the prevalence of those in the studies presented is 10% or less.^{[citation needed]}

References

Perez-Reyes E (2006). "Molecular characterization of T-type calcium channels". Cell Calcium 40 (2): 89–96. doi:10.1016/j.ceca.2006.04.012. PMID 16759699.

Footnotes

^ Hirsch E, Thomas P, Panayiotopoulos C. (2007). "Childhood and absence epilepsies.". Epilepsy: a comprehensive textbook: 2397–2411.
^ Chioza B, Everett K, Aschauer H, Brouwer O, Callenbach P, Covanis A, Dulac O, Durner M, Eeg-Olofsson O, Feucht M, Friis M, Heils A, Kjeldsen M, Larsson K, Lehesjoki A, Nabbout R, Olsson I, Sander T, Sirén A, Robinson R, Rees M, Gardiner R (2006). "Evaluation of CACNA1H in European patients with childhood absence epilepsy.". Epilepsy Res 69 (2): 177–81. doi:10.1016/j.eplepsyres.2006.01.009. PMID 16504478.
^ Wallace R, Marini C, Petrou S, Harkin L, Bowser D, Panchal R, Williams D, Sutherland G, Mulley J, Scheffer I, Berkovic S (2001). "Mutant GABA(A) receptor gamma2-subunit in childhood absence epilepsy and febrile seizures.". Nat Genet 28 (1): 49–52. doi:10.1038/88259. PMID 11326275.
^ Marini C, Harkin L, Wallace R, Mulley J, Scheffer I, Berkovic S (2003). "Childhood absence epilepsy and febrile seizures: a family with a GABA(A) receptor mutation.". Brain 126 (Pt 1): 230–40. doi:10.1093/brain/awg018. PMID 12477709.
^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l Chen Y, Lu J, Pan H, Zhang Y, Wu H, Xu K, Liu X, Jiang Y, Bao X, Yao Z, Ding K, Lo W, Qiang B, Chan P, Shen Y, Wu X (2003). "Association between genetic variation of CACNA1H and childhood absence epilepsy.". Ann Neurol 54 (2): 239–43. doi:10.1002/ana.10607. PMID 12891677.
^ ^a ^b ^c ^d ^e Khosravani H, Altier C, Simms B, Hamming K, Snutch T, Mezeyova J, McRory J, Zamponi G (2004). "Gating effects of mutations in the Cav3.2 T-type calcium channel associated with childhood absence epilepsy.". J Biol Chem 279 (11): 9681–4. doi:10.1074/jbc.C400006200. PMID 14729682.
^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ Vitko I, Chen Y, Arias J, Shen Y, Wu X, Perez-Reyes E (2005). "Functional characterization and neuronal modeling of the effects of childhood absence epilepsy variants of CACNA1H, a T-type calcium channel.". J Neurosci 25 (19): 4844–55. doi:10.1523/JNEUROSCI.0847-05.2005. PMID 15888660.
^ ^a ^b ^c ^d Liang J, Zhang Y, Wang J, Pan H, Wu H, Xu K, Liu X, Jiang Y, Shen Y, Wu X (2006). "New variants in the CACNA1H gene identified in childhood absence epilepsy.". Neurosci Lett 406 (1–2): 27–32. doi:10.1016/j.neulet.2006.06.073. PMID 16905256.
^ ^a ^b ^c ^d Heron S, Phillips H, Mulley J, Mazarib A, Neufeld M, Berkovic S, Scheffer I (2004). "Genetic variation of CACNA1H in idiopathic generalized epilepsy". Ann Neurol 55 (4): 595–6. doi:10.1002/ana.20028. PMID 15048902.
^ ^a ^b ^c Khosravani H, Bladen C, Parker D, Snutch T, McRory J, Zamponi G (2005). "Effects of Cav3.2 channel mutations linked to idiopathic generalized epilepsy". Ann Neurol 57 (5): 745–9. doi:10.1002/ana.20458. PMID 15852375.

External links

Mechanisms of absence seizures (Scholarpedia)

UpToDate Contents

全文を閲覧するには購読必要です。 To read the full text you will need to subscribe.

1. 小児期欠神てんかん childhood absence epilepsy
2. 小児におけるてんかん症候群 epilepsy syndromes in children
3. 抗てんかん剤：作用機序、薬理学、および有害事象 antiepileptic drugs mechanism of action pharmacology and adverse effects
4. 痙攣発作およびてんかんの病態生理 pathophysiology of seizures and epilepsy
5. 国際抗てんかん連盟（ILAE）によるてんかん発作およびてんかんの分類 ilae classification of seizures and epilepsy

English Journal

Brain protein expression changes in WAG/Rij rats, a genetic rat model of absence epilepsy after peripheral lipopolysaccharide treatment.

Györffy B, Kovács Z, Gulyássy P, Simor A, Völgyi K, Orbán G, Baracskay P, Szabó Z, Janáky T, Dobolyi A, Juhász G, Czurkó A, Kékesi KA.Author information Laboratory of Proteomics, Institute of Biology, Eötvös Loránd University, Pázmány P. stny. 1/c, Budapest H-1117, Hungary.AbstractPeripheral injection of bacterial lipopolysaccharide (LPS) facilitates 8-10Hz spike-wave discharges (SWD) characterizing absence epilepsy in WAG/Rij rats. It is unknown however, whether peripherally administered LPS is able to alter the generator areas of epileptic activity at the molecular level. We injected 1mg/kg dose of LPS intraperitoneally into WAG/Rij rats, recorded the body temperature and EEG, and examined the protein expression changes of the proteome 12h after injection in the fronto-parietal cortex and thalamus. We used fluorescent two-dimensional differential gel electrophoresis to investigate the expression profile. We found 16 differentially expressed proteins in the fronto-parietal cortex and 35 proteins in the thalamus. It is known that SWD genesis correlates with the transitional state of sleep-wake cycle thus we performed meta-analysis of the altered proteins in relation to inflammation, epilepsy as well as sleep. The analysis revealed that all categories are highly represented by the altered proteins and these protein-sets have considerable overlap. Protein network modeling suggested that the alterations in the proteome were largely induced by the immune response, which invokes the NFkB signaling pathway. The proteomics and computational analysis verified the known functional interplay between inflammation, epilepsy and sleep and highlighted proteins that are involved in their common synaptic mechanisms. Our physiological findings support the phenomenon that high dose of peripheral LPS injection increases SWD-number, modifies its duration as well as the sleep-wake stages and decreases body temperature.
Brain, behavior, and immunity.Brain Behav Immun.2014 Jan;35:86-95. doi: 10.1016/j.bbi.2013.09.001. Epub 2013 Sep 8.
Peripheral injection of bacterial lipopolysaccharide (LPS) facilitates 8-10Hz spike-wave discharges (SWD) characterizing absence epilepsy in WAG/Rij rats. It is unknown however, whether peripherally administered LPS is able to alter the generator areas of epileptic activity at the molecular level. W
PMID 24021561

Magnetoencephalography localizing spike sources of atypical benign partial epilepsy.

Shiraishi H1, Haginoya K2, Nakagawa E3, Saitoh S1, Kaneko Y4, Nakasato N5, Chan D6, Otsubo H7.Author information 1Department of Pediatrics, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan.2Department of Pediatrics, Tohoku University School of Medicine, Sendai, Miyagi, Japan.3Department of Neurology, National Hospital for Mental, Nervous and Muscular Disorders, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan.4Department of Neurosurgery, National Hospital for Mental, Nervous and Muscular Disorders, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan.5Department of Epileptology, Tohoku University School of Medicine, Sendai, Miyagi, Japan.6Division of Neurology, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada; Neurology Service, Department of Pediatric Medicine, KK Women's and Children's Hospital, Singapore.7Division of Neurology, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada. Electronic address: hiotsubo@rogers.com.AbstractRationale: Atypical benign partial epilepsy (ABPE) is characterized by centro-temporal electroencephalography (EEG) spikes, continuous spike and waves during sleep (CSWS), and multiple seizure types including epileptic negative myoclonus (ENM), but not tonic seizures. This study evaluated the localization of magnetoencephalography (MEG) spike sources (MEGSSs) to investigate the clinical features and mechanism underlying ABPE. Methods: We retrospectively analyzed seizure profiles, scalp video EEG (VEEG) and MEG in ABPE patients. Results: Eighteen ABPE patients were identified (nine girls and nine boys). Seizure onset ranged from 1.3 to 8.8years (median, 2.9years). Initial seizures consisted of focal motor seizures (15 patients) and absences/atypical absences (3). Seventeen patients had multiple seizure types including drop attacks (16), focal motor seizures (16), ENM (14), absences/atypical absences (11) and focal myoclonic seizures (10). VEEG showed centro-temporal spikes and CSWS in all patients. Magnetic resonance imaging (MRI) was reported as normal in all patients. MEGSSs were localized over the following regions: both Rolandic and sylvian (8), peri-sylvian (5), peri-Rolandic (4), parieto-occipital (1), bilateral (10) and unilateral (8). All patients were on more than two antiepileptic medications. ENM and absences/atypical absences were controlled in 14 patients treated with adjunctive ethosuximide. Conclusion: MEG localized the source of centro-temporal spikes and CSWS in the Rolandic-sylvian regions. Centro-temporal spikes, Rolandic-sylvian spike sources and focal motor seizures are evidence that ABPE presents with Rolandic-sylvian onset seizures. ABPE is therefore a unique, age-related and localization-related epilepsy with a Rolandic-sylvian epileptic focus plus possible thalamo-cortical epileptic networks in the developing brain of children.
Brain & development.Brain Dev.2014 Jan;36(1):21-7. doi: 10.1016/j.braindev.2012.12.011. Epub 2013 Feb 4.
Rationale: Atypical benign partial epilepsy (ABPE) is characterized by centro-temporal electroencephalography (EEG) spikes, continuous spike and waves during sleep (CSWS), and multiple seizure types including epileptic negative myoclonus (ENM), but not tonic seizures. This study evaluated the locali
PMID 23384398

Sturge-Weber syndrome with late onset hemiplegic migraine-like attacks and progressive unilateral cerebral atrophy.

Planche V, Chassin O, Leduc L, Regnier W, Kelly A, Colamarino R.Author information Service de Neurologie, CH Jacques Lacarin, France.AbstractBACKGROUND: Sturge-Weber syndrome (SWS) is an uncommon etiology of hemiplegic migraine-like (HM-like) attacks, associated with epilepsy and mental retardation.
Cephalalgia : an international journal of headache.Cephalalgia.2014 Jan;34(1):73-7. doi: 10.1177/0333102413505237. Epub 2013 Sep 17.
BACKGROUND: Sturge-Weber syndrome (SWS) is an uncommon etiology of hemiplegic migraine-like (HM-like) attacks, associated with epilepsy and mental retardation.CASE: We report the case of a 40-year-old woman with SWS who has been suffering from HM-like episodes since she was 24, with no history of se
PMID 24045571

Japanese Journal

小児欠神てんかんと初期診断した25例の臨床経過と脳波所見

福岡大学医学紀要 40(3/4), 105-110, 2013-12
NAID 110009658436

Long-term effectiveness of ethosuximide, valproic acid, and lamotrigine in childhood absence epilepsy

Brain & development 34(5), 344-348, 2012-05-01
NAID 10031050659

Atypical childhood absence epilepsy with preceding or simultaneous generalized tonic clonic seizures

Brain & development 33(7), 589-592, 2011-08-01
NAID 10031121957

Related Pictures

★リンクテーブル★

リンク元	「petit mal epilepsy」「absence epilepsy」「小児欠神てんかん」「juvenile absence epilepsy」
関連記事	「absence」「absence epilepsy」「childhood」「epilepsy」