Juvenile Myoclonic Epilepsy (juvenile + myoclonic_epilepsy)

Distribution by Scientific Domains


Selected Abstracts


Focal Semiologic and Electroencephalographic Features in Patients with Juvenile Myoclonic Epilepsy

EPILEPSIA, Issue 10 2005
Naotaka Usui
Summary:,Purpose: A few reports have described focal electroencephalographic or clinical features or both of juvenile myoclonic epilepsy (JME), but without video-EEG documentation. We examined focal clinical and EEG features in patients with JME who underwent video-EEG monitoring. Methods: Twenty-six patients (nine males and 17 females) who had seizures recorded during video-EEG monitoring were included. Age at seizure onset was 0 to 22 years (mean, 12.3 years), and age at monitoring was 12 to 44 years (mean, 26.5 years). In one patient with left parietooccipital epilepsy, primary generalized tonic,clonic seizures developed after resection of the parietal tumor. Two patients had both temporal lobe epilepsy and JME. Videotaped seizures in each patient were analyzed. Interictal and ictal EEG also were analyzed for any focal features. Results: Focal semiologic features were observed in 12 (46%) of 26 patients. Six patients had focal myoclonic seizures, and two had Figure 4 sign: one with version to the left, and another had left version followed by Figure 4 sign, and left arm clonic seizure. Their ictal EEGs were generalized at onset but with a lateralized evolution over the right hemisphere. The patient who had both JME and left parietooccipital epilepsy, right arm clonic seizure, and Figure 4 sign was seen during a generalized EEG seizure. Interictally, one patient had temporal sharp waves, and another had run of spikes in the right frontal region. Conclusions: Fourteen (54%) of 26 patients with JME exhibited focal semiologic or electroencephalographic features or both. Video-EEG was essential in reaching a correct diagnosis and choosing an appropriate antiepileptic drug regimen. [source]


Juvenile Myoclonic Epilepsy , an experience from north western India

ACTA NEUROLOGICA SCANDINAVICA, Issue 1 2001
A. Panagariya
Objectives, The clinical data on cases of Juvenile Myoclonic Epilepsy (JME) were analysed. Response to initial small dosages (lower than usual) of sodium valproate and further lower maintenance dosages in patients who were seizure free for 2 years on drug were assessed. Material and methods, Seventy-six patients who were diagnosed to have Juvenile Myoclonic Epilepsy on definite criteria were studied. All patients were put on sodium valproate in dosages (lower than usual) for initial control and further lower maintenance dosage and response evaluated. Results, The clinical profile was found to be similar as in other parts of India. There was a female preponderance and average delay of 4.9 years in final diagnosis. Forty-eight (63.1%) patients showed good control on 15 mg/kg/day dosages of sodium valproate. After a seizure free interval of 2 years, 58% of patients could be maintained on small dosages ranging from 3,5 mg/kg/day to 6,8 mg/kg/day. Conclusion, The majority of JME patients responded well not only to sodium valproate in dosages lower than usually prescribed but required very small dosages for maintenance after a seizure free period of 2 years. [source]


DNA variants in coding region of EFHC1: SNPs do not associate with juvenile myoclonic epilepsy

EPILEPSIA, Issue 5 2009
Dongsheng Bai
Summary Purpose:, Juvenile myoclonic epilepsy (JME) accounts for 3 to 12% of all epilepsies. In 2004, we identified a mutation-harboring Mendelian gene that encodes a protein with one EF-hand motif (EFHC1) in chromosome 6p12. We observed one doubly heterozygous and three heterozygous missense mutations in EFHC1 segregating as an autosomal dominant gene with 21 affected members of six Hispanic JME families from California and Mexico. In 2006, similar and three novel missense mutations were reported in sporadic and familial Caucasian JME from Italy and Austria. In this study, we asked if coding single nucleotide polymorphisms (SNPs) of EFHC1 also contribute as susceptibility alleles to JME with complex genetics. Methods:, We screened using denaturing high-performance liquid chromatography (DHPLC) and then directly sequenced the 11 exons of EFHC1 in 130 unrelated JME probands, their 352 family members, and seven exons of EFHC1 in 400,614 ethnically matched controls. We carried out case-control association studies between 124 unrelated Hispanic JME probands and 552,614 ethnically matched controls using four SNPs, rs3804506, rs3804505, rs1266787, and rs17851770. We also performed family-based association on SNPs rs3804506 and rs3804505 in 84 complete JME families using the Family-Based Association Test (FBAT) program. Results:, We found no statistically significant differences between JME probands and controls in case-control association and no genetic transmission disequilibria in family-based association for the tested SNPs. In addition, we identified four new DNA variants in the coding region of EFHC1. Conclusion:, The four coding SNPs, rs3804506, rs3804505, rs1266787, and rs17851770, of EFHC1 may not be susceptibility alleles for JME. [source]


Molecular analysis of the A322D mutation in the GABAA receptor ,1 -subunit causing juvenile myoclonic epilepsy

EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2005
Klaus Krampfl
Abstract Juvenile myoclonic epilepsy (JME) belongs to the most common forms of hereditary epilepsy, the idiopathic generalized epilepsies. Although the mode of inheritance is usually complex, mutations in single genes have been shown to cause the disease in some families with autosomal dominant inheritance. The first mutation in a multigeneration JME family has been recently found in the ,1 -subunit of the GABAA receptor (GABRA1), predicting the single amino acid substitution A322D. We further characterized the functional consequences of this mutation by coexpressing ,1 -, ,2 - and ,2 -subunits in human embryonic kidney (HEK293) cells. By using an ultrafast application system, mutant receptors have shown reduced macroscopic current amplitudes at saturating GABA concentrations and a highly reduced affinity to GABA compared to the wild-type (WT). Dose,response curves for current amplitudes, activation kinetics, and GABA-dependent desensitization parameters showed a parallel shift towards 30- to 40-fold higher GABA concentrations. Both deactivation and resensitization kinetics were considerably accelerated in mutant channels. In addition, mutant receptors labelled with enhanced green fluorescent protein (EGFP) were not integrated in the cell membrane, in contrast to WT receptors. Therefore, the A322D mutation leads to a severe loss-of-function of the human GABAA receptor by several mechanisms, including reduced surface expression, reduced GABA-sensitivity, and accelerated deactivation. These molecular defects could decrease and shorten the resulting inhibitory postsynaptic currents (IPSCs) in vivo, which can induce a hyperexcitability of the postsynaptic membrane and explain the occurrence of epileptic seizures. [source]


DNA variants in coding region of EFHC1: SNPs do not associate with juvenile myoclonic epilepsy

EPILEPSIA, Issue 5 2009
Dongsheng Bai
Summary Purpose:, Juvenile myoclonic epilepsy (JME) accounts for 3 to 12% of all epilepsies. In 2004, we identified a mutation-harboring Mendelian gene that encodes a protein with one EF-hand motif (EFHC1) in chromosome 6p12. We observed one doubly heterozygous and three heterozygous missense mutations in EFHC1 segregating as an autosomal dominant gene with 21 affected members of six Hispanic JME families from California and Mexico. In 2006, similar and three novel missense mutations were reported in sporadic and familial Caucasian JME from Italy and Austria. In this study, we asked if coding single nucleotide polymorphisms (SNPs) of EFHC1 also contribute as susceptibility alleles to JME with complex genetics. Methods:, We screened using denaturing high-performance liquid chromatography (DHPLC) and then directly sequenced the 11 exons of EFHC1 in 130 unrelated JME probands, their 352 family members, and seven exons of EFHC1 in 400,614 ethnically matched controls. We carried out case-control association studies between 124 unrelated Hispanic JME probands and 552,614 ethnically matched controls using four SNPs, rs3804506, rs3804505, rs1266787, and rs17851770. We also performed family-based association on SNPs rs3804506 and rs3804505 in 84 complete JME families using the Family-Based Association Test (FBAT) program. Results:, We found no statistically significant differences between JME probands and controls in case-control association and no genetic transmission disequilibria in family-based association for the tested SNPs. In addition, we identified four new DNA variants in the coding region of EFHC1. Conclusion:, The four coding SNPs, rs3804506, rs3804505, rs1266787, and rs17851770, of EFHC1 may not be susceptibility alleles for JME. [source]


Symptomatic Epilepsies Imitating Idiopathic Generalized Epilepsies

EPILEPSIA, Issue 2005
Hirokazu Oguni
Summary:, The diagnosis of idiopathic generalized epilepsies (IGEs) is not generally difficult if one follows the clinical and electroencephalogram (EEG) definitions of each subsyndrome that constitutes IGEs. In contrast, symptomatic epilepsies develop based on organic brain lesions and are easily diagnosed by the presence of developmental delay, neurologic abnormalities, and a characteristic seizure and EEG pattern. However, in clinical practice, it is sometimes difficult to differentiate IGEs from symptomatic epilepsies, especially when the clinical course from the onset of epilepsy is too short to exhibit typical clinical and EEG findings of either epilepsy type, or when patients with symptomatic epilepsies have atypical features that imitate the clinical characteristics of IGEs. The neurodegenerative or metabolic disorders at times start during the clinical course with epileptic seizures and later show typical neurologic abnormalities. The newly recognized metabolic disorder of glucose transporter type 1 deficiency syndrome (Glut-1 DS) may start with myoclonic seizures at an age of less than 1 year and imitate benign myoclonic epilepsy in infancy early in the clinical course. Progressive myoclonus epilepsies (PMEs) that develop at 1,4 years of age at times imitate epilepsy with myoclonic-astatic seizures with respect to the presence of astatic seizures and an epileptic encephalopathic EEG pattern. In addition, young children with focal cortical dysplasia may also have similar clinical and EEG patterns, although the latter may become localized after treatment. Approximately 15% of patients with juvenile myoclonic epilepsy (JME) are resistant to antiepileptic drugs (AEDs) and may require extensive study to make a differential diagnosis from symptomatic epilepsies. PMEs that develop during adolescence may imitate JME early in the clinical course; however, a detailed history and the differentiation between myoclonic seizures and myoclonus would help to distinguish both conditions. The diagnosis of IGEs is very demanding for patients with atypical features with regard to seizure type, EEG findings, and response to appropriate AEDs. [source]


Evidence-based Treatment of Idiopathic Generalized Epilepsies with Older Antiepileptic Drugs

EPILEPSIA, Issue 2005
Nikolas Hitiris
Summary:, Older antiepileptic drugs continue to play a major role in the treatment of the idiopathic generalized epilepsies. Comparative studies of ethosuximide and valproate have demonstrated equivalence in the treatment of childhood absence epilepsy. Valproate can be regarded as the recommended first-line treatment for juvenile myoclonic epilepsy based on case series reports. Studies in patients with generalized tonic-clonic seizures have not separated out idiopathic from secondary generalized events. Treatment for the other idiopathic generalized epilepsy syndromes lacks evidence other than a few case reports and diverse expert opinion. Further randomized controlled trials of older antiepileptic drugs are recommended to solidify the evidence-based treatment of the idiopathic generalized epilepsies. [source]


Focal Semiologic and Electroencephalographic Features in Patients with Juvenile Myoclonic Epilepsy

EPILEPSIA, Issue 10 2005
Naotaka Usui
Summary:,Purpose: A few reports have described focal electroencephalographic or clinical features or both of juvenile myoclonic epilepsy (JME), but without video-EEG documentation. We examined focal clinical and EEG features in patients with JME who underwent video-EEG monitoring. Methods: Twenty-six patients (nine males and 17 females) who had seizures recorded during video-EEG monitoring were included. Age at seizure onset was 0 to 22 years (mean, 12.3 years), and age at monitoring was 12 to 44 years (mean, 26.5 years). In one patient with left parietooccipital epilepsy, primary generalized tonic,clonic seizures developed after resection of the parietal tumor. Two patients had both temporal lobe epilepsy and JME. Videotaped seizures in each patient were analyzed. Interictal and ictal EEG also were analyzed for any focal features. Results: Focal semiologic features were observed in 12 (46%) of 26 patients. Six patients had focal myoclonic seizures, and two had Figure 4 sign: one with version to the left, and another had left version followed by Figure 4 sign, and left arm clonic seizure. Their ictal EEGs were generalized at onset but with a lateralized evolution over the right hemisphere. The patient who had both JME and left parietooccipital epilepsy, right arm clonic seizure, and Figure 4 sign was seen during a generalized EEG seizure. Interictally, one patient had temporal sharp waves, and another had run of spikes in the right frontal region. Conclusions: Fourteen (54%) of 26 patients with JME exhibited focal semiologic or electroencephalographic features or both. Video-EEG was essential in reaching a correct diagnosis and choosing an appropriate antiepileptic drug regimen. [source]


Genetic Architecture of Idiopathic Generalized Epilepsy: Clinical Genetic Analysis of 55 Multiplex Families

EPILEPSIA, Issue 5 2004
Carla Marini
Summary: Purpose: In families with idiopathic generalized epilepsy (IGE), multiple IGE subsyndromes may occur. We performed a genetic study of IGE families to clarify the genetic relation of the IGE subsyndromes and to improve understanding of the mode(s) of inheritance. Methods: Clinical and genealogic data were obtained on probands with IGE and family members with a history of seizures. Families were grouped according to the probands' IGE subsyndrome: childhood absence epilepsy (CAE), juvenile absence epilepsy (JAE), juvenile myoclonic epilepsy (JME), and IGE with tonic,clonic seizures only (IGE-TCS). The subsyndromes in the relatives were analyzed. Mutations in genes encoding ,1 and ,2 ,-aminobutyric acid (GABA)-receptor subunits, ,1 and ,1 sodium channel subunits, and the chloride channel CLC-2 were sought. Results: Fifty-five families were studied. 122 (13%) of 937 first- and second-degree relatives had seizures. Phenotypic concordance within families of CAE and JME probands was 28 and 27%, respectively. JAE and IGE-TCS families had a much lower concordance (10 and 13%), and in the JAE group, 31% of relatives had CAE. JME was rare among affected relatives of CAE and JAE probands and vice versa. Mothers were more frequently affected than fathers. No GABA-receptor or sodium or chloride channel gene mutations were identified. Conclusions: The clinical genetic analysis of this set of families suggests that CAE and JAE share a close genetic relation, whereas JME is a more distinct entity. Febrile seizures and epilepsy with unclassified tonic,clonic seizures were frequent in affected relatives of all IGE individuals, perhaps representing a nonspecific susceptibility to seizures. A maternal effect also was seen. Our findings are consistent with an oligogenic model of inheritance. [source]


Clinical Presentations and Phenomenology of Myoclonus

EPILEPSIA, Issue 2003
Edward Faught
Summary: The term "myoclonus" has been used to describe heterogeneous phenomena involving sudden movements, but there is no generally accepted, precise definition of myoclonus. Myoclonus can often be classified based on electroencephalographic (EEG) and/or electromyographic (EMG) data. Some myoclonic epilepsy syndromes, including juvenile myoclonic epilepsy, may frequently be misdiagnosed because of failure to obtain a complete patient history and/or failure to appreciate characteristic EEG changes. A good understanding of the features associated with myoclonic disorders (particularly the myoclonic epilepsies) and of features associated with other neurologic disorders that are often confused with myoclonic disorders is an invaluable aid in obtaining an accurate diagnosis and will ultimately help in determining the best course of treatment for patients. [source]


Prognostic Significance of Failure of the Initial Antiepileptic Drug in Children with Absence Epilepsy

EPILEPSIA, Issue 6 2001
Elaine Wirrell
Summary: ,Purpose: In children with childhood absence epilepsy (CAE) and juvenile absence epilepsy (JAE), to determine the impact of failure of initial antiepileptic drug (AED) for lack of efficacy in eventual seizure control and long-term remission of epilepsy. Methods: Centralized EEG records for the province of Nova Scotia allowed identification of all children seen with CAE or JAE between 1977 and 1985. Information regarding success or failure of initial AED in fully controlling seizures and long-term seizure control and remission of epilepsy was collected by patient questionnaire and chart review. Results: Eighty-six of 92 eligible patients were followed up (75 CAE, 11 JAE). Initial AED treatment was successful in 52 (60%) of 86. Success tended to be greater for valproate (VPA) than for other AEDs (p = 0.07), and lower if generalized tonic,clonic or myoclonic seizures coexisted (p < 0.004 and p < 0.03). Terminal remission was more likely if the initial AED was successful than if it had failed (69% vs. 41%; p < 0.02). Compared with those in whom the initial AED was successful, subjects whose initial AED had failed were more likely to progress to juvenile myoclonic epilepsy (JME) at last follow-up (32% vs. 10%; p < 0.02) and to develop intractable epilepsy (17% vs. 2%; p < 0.04). Conclusions: Initial AED was successful in 60% of children with AE. If the first AED failed, the outcome was less favorable, with a lower rate of terminal remission and a higher rate of progression to JME and intractable epilepsy. [source]


Photosensitivity in Relation to Epileptic Syndromes: A Survey from an Epilepsy Center in Japan

EPILEPSIA, Issue 3 2001
Hideaki Shiraishi
Summary: ,Purpose: We examined the incidence and distribution of photosensitivity among the different age groups and different types of epilepsies and epileptic syndromes. Furthermore, we considered the influence of ethnic and geographic factors on the incidence of photoparoxysmal response (PPR) in epilepsy patients. Methods: We analyzed the responses to intermittent photic stimulation (IPS) by using a Grass PS22 or PS33 photic stimulator for in 2,187 unselected patients with epilepsy who were treated in our center. Results: The classic PPR was elicited in 37 (1.7%) patients. The mean age of these 37 patients was 17.0 years. The subpopulation of patients having PPR included 2.0% of all patients with symptomatic generalized epilepsy, 5.6% (p < 0.01) of those with idiopathic generalized epilepsy, 0.7% of those with symptomatic localization-related epilepsy, and 2.9% of those with undetermined epilepsy. PPR accounted for 17.4 % (p < 0.01) of the patients with juvenile myoclonic epilepsy, 7.6% (p < 0.01) of those with grand mal on awakening, and 6.1% (p < 0.01) of those with symptomatic occipital lobe epilepsy. The incidence of PPR increased in patients up to age 15 years, and suddenly decreased after age 20 years. Conclusion: The present study presents the first report from eastern Asia, analyzing the incidence of PPR with a restricted definition comparable to the other studies, and the rate of PPR was relatively low compared with the studies performed in the European countries. We could confirm the clear relation between age and positive PPR. [source]


Molecular analysis of the A322D mutation in the GABAA receptor ,1 -subunit causing juvenile myoclonic epilepsy

EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2005
Klaus Krampfl
Abstract Juvenile myoclonic epilepsy (JME) belongs to the most common forms of hereditary epilepsy, the idiopathic generalized epilepsies. Although the mode of inheritance is usually complex, mutations in single genes have been shown to cause the disease in some families with autosomal dominant inheritance. The first mutation in a multigeneration JME family has been recently found in the ,1 -subunit of the GABAA receptor (GABRA1), predicting the single amino acid substitution A322D. We further characterized the functional consequences of this mutation by coexpressing ,1 -, ,2 - and ,2 -subunits in human embryonic kidney (HEK293) cells. By using an ultrafast application system, mutant receptors have shown reduced macroscopic current amplitudes at saturating GABA concentrations and a highly reduced affinity to GABA compared to the wild-type (WT). Dose,response curves for current amplitudes, activation kinetics, and GABA-dependent desensitization parameters showed a parallel shift towards 30- to 40-fold higher GABA concentrations. Both deactivation and resensitization kinetics were considerably accelerated in mutant channels. In addition, mutant receptors labelled with enhanced green fluorescent protein (EGFP) were not integrated in the cell membrane, in contrast to WT receptors. Therefore, the A322D mutation leads to a severe loss-of-function of the human GABAA receptor by several mechanisms, including reduced surface expression, reduced GABA-sensitivity, and accelerated deactivation. These molecular defects could decrease and shorten the resulting inhibitory postsynaptic currents (IPSCs) in vivo, which can induce a hyperexcitability of the postsynaptic membrane and explain the occurrence of epileptic seizures. [source]


Myoclonic status epilepticus: Video presentation,,

MOVEMENT DISORDERS, Issue 2 2002
Aman Badhwar BSc
A young woman with juvenile myoclonic epilepsy had recurrent attacks of myoclonic status epilepticus related to a long history of limited compliance and irregular sleep. The diagnosis of this clinical pattern is based mainly on clinical description. A home video captured an attack. © 2002 Movement Disorder Society. [source]


Sulthiame in childhood epilepsy

PEDIATRICS INTERNATIONAL, Issue 5 2004
Bruria Ben-Zeev
AbstractBackground:,Sulthiame is a central carbonic anhydrase inhibitor found to be effective for both partial and generalized seizures. It has been in use in some European countries and in Israel for over 30 years. The aim of the present study was to evaluate the efficacy and tolerability of sulthiame in childhood epilepsy by conducting a multicenter, retrospective study of patients who received this drug. Methods:,The charts of 125 consecutive epilepsy patients treated with sulthiame as monotherapy or add-on therapy were reviewed. Results:,Twenty-nine out of 39 patients with benign focal epilepsy of childhood became seizure-free. Total seizure control was also achieved in 17 of 42 patients with symptomatic, non-refractory localization-related epilepsy, and in all 10 cases with juvenile myoclonic epilepsy. Complete normalization of the EEG occurred in 13 of 20 patients with benign partial epilepy of childhood. Side-effects were minimal and caused discontinuation of treatment in only seven children. Conclusion:,The high tolerability, efficacy, convenience of use and low cost suggest that sulthiame should become a first line drug in the benign partial epilepsies of childhood and juvenile myoclonic epilepsy. It also has a role as add-on treatment in other partial and myoclonic epilepsies. [source]


Focal clinical and electroencephalographic features in patients with juvenile myoclonic epilepsy

ACTA NEUROLOGICA SCANDINAVICA, Issue 2 2010
S. S. Jayalakshmi
Jayalakshmi SS, Srinivasa Rao B, Sailaja S. Focal clinical and electroencephalographic features in patients with juvenile myoclonic epilepsy. Acta Neurol Scand: 2010: 122: 115,123. © 2009 The Authors Journal compilation © 2009 Blackwell Munksgaard. Objective,,, To identify prevalence and factors associated with occurrence of focal clinical and electroencephalogram (EEG) abnormalities in patients with juvenile myoclonic epilepsy (JME). Materials and methods,,, Clinical asymmetries in the seizures and focal EEG abnormalities were analyzed in 266 patients with JME. Results,,, All the patients had myoclonic jerks (MJ) and generalized tonic-clonic seizures (GTCS); 56 (21%) had absence seizures. Asymmetry in clinical seizures was reported in 45 (16.9%) and focal EEG abnormalities were noted in 92 (45.5%) patients. Amplitude asymmetry or focal onset of generalized discharges was noted in 41 (44.6%) and independent focal EEG abnormalities in 30 (32.6%) patients. A statistically significant association was seen with the presence of GTCS and MJ (P = 0.007), a family history of epilepsy (P = 0.001) and drug resistance (P = 0.04) and the occurrence of focal EEG abnormalities. Conclusion,,, Patients with JME showed focal clinical and EEG features. These features should not be misinterpreted as indicative of partial epilepsy. [source]


Role of valproate across the ages.

ACTA NEUROLOGICA SCANDINAVICA, Issue 2006
Treatment of epilepsy in adults
A workshop was held in Göteborg in June 2005 to discuss the place of valproate in treating adult epilepsies. Consensus positions were developed on the epilepsy types for which the drug is most suitable and the use of valproate in women of child-bearing age, in men and in patients with psychiatric comorbidity. Valproate was considered to be effective across a broad variety of epilepsy syndromes and seizure types and should be considered a suitable choice for first-line monotherapy of juvenile myoclonic epilepsy and other idiopathic generalized epilepsies. The use of valproate by women of child-bearing age is associated with potential harm to the foetus. A conservative approach to treatment is recommended in these patients whereby alternative antiepileptic drugs should be proposed to women planning pregnancies wherever satisfactory seizure control can be thereby maintained. In cases where valproate is used during pregnancy, either because the pregnancy was unplanned or because alternative treatment options of equivalent efficacy are unavailable, appropriate counselling, precautionary measures and monitoring should be provided. The evidence for an impact of valproate on male reproductive health is equivocal and considerations of male fertility should not be taken into account in deciding whether to prescribe valproate to men. Valproate can be proposed safely to patients with comorbid psychiatric disease or underlying psychiatric vulnerability. [source]