Epilepsy idiopathic

Benign familial neonatal convulsion is an idiopathic form of epilepsy beginning within the first six months after birth. Seizures include generalized and mixed, starting with tonic posture, ocular symptoms, and apnea, and often progress to clonic movements and motor automatisms. 

Idiopathic epilepsies These syndromes are thought to be due to genetic alterations, but the underlying etiology is not identified. Neurologic functions are completely normal apart from the occurrence of seizures. 

A complete description of a patient s epilepsy should include the seizure type with the epilepsy or syndrome type (i.e., idiopathic, symptomatic, or cryptogenic). 

TABLE 37-3 Idiopathic human epilepsies genes and syndromes... 

Tables 37-3 and 37-4 list the genes responsible for idiopathic and symptomatic epilepsies in humans, respectively. Table 37-5 lists genes identified as causing 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. 

Sander, T., Berlin, W., Gscheidel, N., Wendel, B., Janz, D., and Hoehe, M. R. (2000) Genetic variation of the human mu-opioid receptor and susceptibility to idiopathic absence epilepsy. Epilepsy Res. 39, 57-61. 

Epilepsy (or epilepsies, since markedly different clinical entities exist) is a common neurological abnormality affecting about 1% of the human population. Epilepsy is a chronic, usually life-long disorder characterized by recurrent seizures or convulsions and usually, episodes of unconsciousness and/or amnesia. Table 32.1 illustrates the major types of epileptic seizures. Patients often exhibit more than one type. In most instances, the cause of the seizure disorder is not known (idiopathic epilepsy), although trauma during birth is suspected of being one cause. 

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 epilepsies are estimated to affect 20-40 million individuals worldwide and are more common in children than in adults. They are classified into two broad groups primary or idiopathic epilepsy is the term applied to those types for which no specific cause can be identified, and secondary or symptomatic epilepsy arises when the symptoms are associated with trauma, neoplasm, infection, cerebrovascular disease or some other physically induced lesion of the brain. Seizures that accompany severe metabolic disturbances are not classified as epilepsy. 

Yang WP, Levesque PC, Little WA et al. (1998) Functional expression of two KvLQTl-related potassium channels responsible for an inherited idiopathic epilepsy. J Biol Chem 273(31) 19419-19423... 

Primary epilepsy When no specific anatomic cause for the seizure, such as trauma or neoplasm, is evident the syndrome is called idiopathic or primary epilepsy. These seizures may be produced by an inherited abnormality in the central nervous system (CNS). Patients are treated chronically with antiepileptic drugs, often for life. 

Seizures occur more infrequently in horses than in dogs and cats. Seizures are seen in adult horses from brain trauma, bacterial meningitis, viral encephalitis and, rarely, hepatic encephalopathy or vascular accidents. Convulsions are seen in young neonatal foals with NMS as a result of brain hypoxia and in Arabian foals aged 3-9 months (idiopathic Arabian epilepsy). Anticonvulsant therapy is used to prevent the spread of the seizure focus, increase (raise) the seizure threshold and decrease the electrical excitement of abnormal... 

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]. 

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