Idiopathic generalized epilepsy

Simister, R. J., McLean, M. A., Barker, G. J. and Duncan J. S. Proton MRS reveals frontal lobe metabolite abnormalities in idiopathic generalized epilepsy. Neurology 61 897-902, 2003. 

Figure 5. Mutations in the human Cav3.2 (T-type) voltage-gated calcium channel associated with Childhood Absence Epilepsy (CAE), Idiopathic Generalized Epilepsy (IGE) and Autism Spectrum Disorder (ASD)...

Table 7. CACNA1H (Cav3.2, ct1H) Functional results for mutations associated with CAE = childhood absence epilepsy, IGE = Idiopathic generalized epilepsy and ASD = Autism Spectrum Disorder (only those mutations with functional data are listed)...

Khosravani H, Bladen C, Parker DB, Snutch TP, McRory JE, Zamponi GW (2005) Effects of Cav3.2 channel mutations linked to idiopathic generalized epilepsy. Ann Neurol 57 745—749. 

Sander T (1996) The genetics of idiopathic generalized epilepsy implications for the understanding of its aetiology. Mol Med Today 2 173-180. 

Khosravani H, Zamponi GW (2006) Voltage-gated calcium channels and idiopathic generalized epilepsies. Physiol Rev 86 941-66... 

The CASR has been further implicated in neurological functions since an idiopathic epilepsy locus was mapped to the CASR locus and novel, rare missense CASR variants were identified in idiopathic generalized epilepsy [58, 59]. Mutations involved in the idiopathic epilepsy syndrome disrupt an arginine-rich retention motif in the proximal part of the CASR cytoplasmic tail promoting greater cell-surface expression and activity of the CASR than normal [59]. 

Valproic acid is the drug of choice for myoclonic seizures in juvenile myoclonic epilepsy, in which myoclonic seizures often coexist with tonic-clonic and absence seizures. No trials have examined any of the newly introduced drugs for patients with juvenile myoclonic epilepsy or other idiopathic generalized epilepsy syndromes. 

Alterations in the structure or function of an ion channel caused by mutations in a gene encoding one of the channel s subunits are termed channelopathies. Initially, these abnormalities were associated with cardiac and muscular disorders, but today, it is recognized that channelopathies are responsible for several forms of epilepsy (15,16). Presently, most of the discovered channel mutations appear to be associated with the development of idiopathic generalized epilepsy most partial seizures are believed to be acquired. Minor alterations in gene structure or expression, however, may predispose a given individual to partial seizures. It is estimated that 40% of adult and childhood epilepsy may result from genetic factors. 

Thomas P, Valton L, Genton P. Absence and myoclonic status epilepticus precipitated by antiepileptic drugs in idiopathic generalized epilepsy. Brain 2006 129 1281-1292. 

Gelisse P, Genton P, Kuate C, et ai. Worsening of seizures by oxcarbazepine in Juvenile idiopathic generalized epilepsies. Epilepsia 2004 45 1282-1286. 

Grunewald R. Levetiracetam in the treatment of idiopathic generalized epilepsies. Epilepsia 2005 46(Suppl... 

Knake S, Hamer HM, Schomburg U, et al. Tiagabine-induced absence status in idiopathic generalized epilepsy. Seizure 1999 8 314-317. 

Gardiner, M (2005) Genetics of idiopathic generalized epilepsies. Epilepsia, 46 (Suppl 9) 15-20. 

A 21-year-old man with idiopathic generalized epilepsy took about 8 g of topiramate in a suicide attempt and had non-convulsive status epilepticus, which was treated with intravenous lorazepam [30F ]. 

Mineral balance Changes in calcium metabolism and bone turnover have been evaluated in 20 post-pubertal men with idiopathic generalized epilepsy after 12 months of valproate monotherapy and in 20 post-pubertal sex- and age-matched healthy controls [331 ]. Both markers of bone formation and resorption were significantly higher than baseline in those who took valproate. 

Holland KD, Monahan S, Morita D, Vartzelis G, Glauser TA. Valproate in children with newly diagnosed idiopathic generalized epilepsy. Acta Neurol Scand 2010 121(3) 149-53. 

A 3-year-old boy with idiopathic generalized epilepsy lost his ability to detect and recognize taste and smell during treatment with topiramate, and improved after drug withdrawal [310 ]. 

Teratogenicity In an analysis of the medical records of 284 valproate-exposed pregnancies in the North American Antiepileptic Drug Pregnancy Registry 30 (11.0%) were associated with malformations [388 ]. There were 15/126 (12%) malformations in patients with idiopathic generalized epilepsy, 4/28 (14%) in patients with partial epilepsy, 9/105 (9%) in those... 

A 35-year-old woman taking valproate 500 mg bd and phenobarbital 75 m day for idiopathic generalized epilepsy who had been seizure-free for 3 years had a recurrence of myoclonic jerks, absences, and a tonic-clonic seizure a few days after taking a dietary supplementation that contained chitosan 500 mg bd for weight loss. The seizures remitted after chitosan was stopped. Three months later she restarted chitosan and within 5 days once more had seizures. Semm valproate was undetectable. Chitosan was withdrawn, the seizures remitted, and the valproate concentration returned to baseline (50 mg/1) within 4 days. 

Observational studies In an open prospective study in 13 patients with idiopathic generalized epilepsies who were taking zonisamide mean dosage 319 mg/day, 12 continued to take zonisamide at month 6... 

Marinas A, Villanueva V, Girdldez BG, Molins A, Salas-Puig J, Serratosa JM. Efficacy and tolerability of zonisamide in idiopathic generalized epilepsy. Epileptic Disord 2009 11(1) 61-6. 

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