Two-year efficacy of lacosamide as adjunctive therapy for generalized tonic-clonic seizures in patients with juvenile myoclonic epilepsy

ObjectiveTo report the long-term efficacy of adjunctive lacosamide therapy in patients with juvenile myoclonic epilepsy whose generalized tonic-clonic seizures were significantly reduced by treatment.MethodsA retrospective study was conducted in patients who visited the Department of Child Neurology, National Hospital Organization Nishiniigata Chuo Hospital and the Department of Pediatrics, National Hospital Organization Nagasaki Medical Center. Among patients who had been diagnosed with juvenile myoclonic epilepsy, those who received lacosamide as adjunctive therapy for refractory generalized tonic-clonic seizures for at least 2 years from January 2017 to December 2022, and who achieved seizure freedom or >50% seizure reduction in tonic-clonic seizures were included. The medical records and neurophysiological data of the patients were reviewed retrospectively.ResultsFour patients met the inclusion criteria. The mean age at the onset of epilepsy was 11.3 years (range 10–12), and the mean age of starting lacosamide was 17.5 years (range 16–21). All patients received two or more antiseizure medications prior to lacosamide. Three of four patients had seizure freedom for more than 2 years, and the one remaining patient had >50% seizure reduction for more than one year. Only one patient had recurrent myoclonic seizures after starting lacosamide. The mean lacosamide dose at the last visit was 425 mg/day (range 300–600).ConclusionAdjunctive lacosamide therapy might be a treatment option for juvenile myoclonic epilepsy with generalized tonic-clonic seizures, which are not responsive to standard antiseizure medications.     

Focal semiologic and electroencephalographic features in patients with juvenile myoclonic epilepsy

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.     

The Absence Epilepsies

Four syndromes comprise the absence epilepsies. Each is classically associated with the absence seizure, although other syndromes also have absence attacks as part of their repertoire. The most common syndrome is childhood absence epilepsy; it usually occurs in the age range of 6–7 years. The absence seizures may occur many times daily, and the electroencephalographic (EEG) characteristics are the most typical of the absence epilepsies. The second form of absence epilepsies is juvenile absence epilepsy; it begins near puberty and may represent a continuum from the childhood form. Myoclonic seizures are more common than in the childhood form, and the spike-wave discharges in the EEG are often faster than that seen in childhood absence epilepsy. The third form of absence epilepsy is juvenile myoclonic epilepsy, characterized especially by myoclonic jerks in the morning; these attacks occasionally progress to generalized tonic-clonic seizures. The final form of absence epilepsy is epilepsy with myoclonic absences, a rare disorder with a specific form of absence seizures. The absence seizure itself is observed to a greater or lesser extent in all of these syndromes. This seizure is a curious event, and its causes are poorly explained by current knowledge of the fundamental mechanisms of the epilepsies. Although the etiology of the absence seizure at a biochemical level is unknown, some studies suggest that certain low-threshold calcium ion currents (T currents), which are partially controlled by GABA-B mechanisms, may activate burst firing of thalamic neurons, initiating an absence seizure. The evidence of a genetic predisposition for the absence epilepsies is overwhelming. Although the nature of the genetic abnormality remains unclear, promising investigations may soon reveal the location and the nature of the genetic defect.     

The Seizure Prognosis of Juvenile Myoclonic Epilepsy

Abstract: Thirty-two patients with juvenile myoclonic epilepsy (JME) were studied to evaluate the seizure prognosis. The response to antiepileptic drugs ww excellent in 68%, but the patients, who had much more focal discharges on EEG and were sensitive to neuropsychological EEG activations at the beginning of treatment, had an unfavorable outcome. A combination of absence seizure alone resulted in the excellent prognosis for both absence and myoclonic seizures, and a combination of generalized tonic-clonic seizure on awakening related to rare myoclonic seizures. These findings suggest that the outcome of JME would be predicted by the EEG abnormality and the combination of the other types of seizures, which are probably determined by the pathophysiology at the beginning of treatment.     

Focal clinical and electroencephalographic features in patients with juvenile myoclonic epilepsy

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.     

Clinical genetic study in juvenile myoclonic epilepsy

PurposeTo evaluate clinical features of probands with juvenile myoclonic epilepsy (JME) and affected members of their families in order to study clinical genetics of JME.MethodThirteen unrelated families with at least two members with history of seizures were identified; clinical and genealogic data were collected from JME probands and family members.ResultsAll probands had myoclonic and generalized tonic–clonic seizures (GTCS), while absences occurred in 25% of them. The average age of seizure onset was 13 years. Totally 22 members from 13 families had history of seizures with average age of seizure onset at 18 years. Ten family members had JME, three had epilepsy with GTCS, two had juvenile absence epilepsy, one had adult onset myoclonic epilepsy and six of the affected individuals had unclassified type of epilepsy. In five families, JME was the solely clinical feature. JME dominated among siblings, while phenotypic heterogeneity was observed in second and third degree relatives. In three multi-generation families, members with adult onset genetic generalized epilepsies (GGE) were identified.ConclusionWe found phenotypic heterogeneity regarding epilepsy type and age of seizure onset. Using pedigree analysis, we found no evidence for preferential maternal or any other distinctive inheritance pattern. Further study is needed to confirm and clarify the results.     

Rotatory seizures in juvenile myoclonic epilepsy

Rotatory seizures have been reported in association with focal intracranial lesions. This type of seizure was also described in patients with primary generalized epilepsies. To our knowledge, there is only one previous publication denoted an association between juvenile myoclonic epilepsy (JME) and rotatory seizures. We present two female patients with JME and rotatory seizures together. The onset of myoclonic jerks and generalized tonic clonic (GTC) seizures was in their midteens. Their interictal EEGs showed bilateral symmetric spike and polyspike wave discharges. The rotatory seizures of the patients started at age of 26 and 33 years, respectively. In one of the patients, turning to the left was followed by three or four complete turns, after then, she had GTC seizures. The other patient has turned to the right with only one or two turns and sometimes continued with GTC seizures. Neuroradiologic investigations including brain CT, MRI, and SPECT were performed. Response to valproate therapy of rotatory seizures was good. We believe that rotatory seizures are rarely seen in JME patients, and this causes false diagnosis which lead unsuitable drug choice.     

31例青少年肌阵挛性癫痫临床表现脑电图特点及误诊分析

目的 回顾性分析31例青少年肌阵挛性癫痫(JME)患者的临床、脑电图特点及误诊原因.方法 收集2008年9月～2011年1月在我院癫痫诊治中心诊治的31例JME患者,对其临床表现、脑电图改变及药物治疗疗效进行总结性分析.结果 31例患者表现单纯肌阵挛发作者12例;肌阵挛伴全身强直-阵挛发作者15例;肌阵挛伴失神发作者4例.长程录像脑电图检查,24例患者于监测过程中出现肌阵挛发作,脑电见与发作同步的对称性、泛化性多棘慢波、棘慢波爆发.既往就诊中诊断为全身强直-阵挛发作者17例,抽动症者8例,部分性发作者4例,正常者2例.依据发作类型给予治疗后肌阵挛症状1w内消失者13人;2w内消失者11人;1个月内消失者6人,每月内均有3～4次肌阵挛发作者1人.继发的全身强直-阵挛性发作,半年内消失者20例;1年内消失者11例.结论 青少年肌阵挛性癫痫,以短暂的、无节律性、不规则的肌阵挛抽动为特点,由于症状不典型容易造成误诊,长程录像脑电图检查,附加闪光刺激、睡眠剥夺等诱发试验,提高阳性诊断率,对症治疗效果好.     

How to diagnose and classify idiopathic (genetic) generalized epilepsies

Idiopathic or genetic generalized epilepsies (IGE) constitute an electroclinically well‐defined group that accounts for almost one third of all people with epilepsy. They consist of four well‐established syndromes and some other rarer phenotypes. The main four IGEs are juvenile myoclonic epilepsy, childhood absence epilepsy, juvenile absence epilepsy and IGE with generalized tonic‐clonic seizures alone. There are three main seizure types in IGE, namely generalized tonic‐clonic seizures, typical absences and myoclonic seizures, occurring either alone or in any combination. Diagnosing IGEs requires a multidimensional approach. The diagnostic process begins with a thorough medical history with a specific focus on seizure types, age at onset, timing and triggers. Comorbidities and family history should be questioned comprehensively. The EEG can provide valuable information for the diagnosis, including specific IGE syndromes, and therefore contribute to their optimal pharmacological treatment and management.     

Outcome of children with juvenile absence epilepsy

The incidence and natural history of childhood absence epilepsy are well documented, but those of juvenile absence epilepsy are poorly delineated. We conducted a retrospective chart study to evaluate the incidence and outcome of patients with juvenile absence epilepsy by retrieving the medical records of consecutive patients with juvenile absence epilepsy who were evaluated in three pediatric neurology outpatient clinics in Israel. Inclusion criteria included the onset of epilepsy after the age of 10 years and follow-up until at least 15 years of age. The patients with an electroencephalogram (EEG) suggestive of myoclonic epilepsy (polyspike and wave) were excluded from the study. Seventeen patients (10 female and 7 male) fulfilled the inclusion criteria for juvenile absence epilepsy. They presented with epilepsy at a mean age of 11.94 years (range 10-16.5 years). The mean duration of follow-up was 6.05 years (range 2-12 years). Five patients (29.4%) had a family history of epilepsy. All 17 patients had a normal neurodevelopmental status. Eight patients (47%) experienced generalized tonic-clonic seizures. At follow-up, eight patients (43.7%) were seizure free. Only three (37.5%) of the patients who experienced generalized tonic-clonic seizures were seizure free during follow-up compared with five (55.5%) patients without generalized tonic-clonic seizures. Our results indicate that the outcome of patients with juvenile absence epilepsy is less favorable than children with childhood absence epilepsy and that the presence of generalized tonic-clonic seizures is a predictor for poorer outcome.     

Photosensitive benign myoclonic epilepsy in infancy

PURPOSE: To describe the electroclinical features of subjects who presented with a photosensitive benign myoclonic epilepsy in infancy (PBMEI). METHODS: The patients were selected from a group of epileptic subjects with seizure onset in infancy or early childhood. Inclusion criteria were the presence of photic-induced myoclonic seizures and a favorable outcome. Cases with less than 24 month follow up were excluded from the analysis. RESULTS: Eight patients were identified (4 males, 4 females). Personal history was uneventful. All of them had familial antecedents of epilepsy. Psychomotor development was normal in 6 cases, both before and after seizure onset. One patient showed a mild mental retardation and a further patient showed some behavioral disturbances. Neuroradiological investigations, when performed (5 cases), gave normal results. The clinical manifestations were typical and could vary from upward movements of the eyes to myoclonic jerks of the head and shoulders, isolated or briefly repetitive, never causing a fall. Age of onset was between 11 months and 3 years and 2 months. Characteristically, the seizures were always triggered by photic stimulation. Non photo-induced spontaneous myoclonic attacks were reported in 2 cases during the follow-up. Other types of seizures were present at follow-up in 2 cases. The outcome was favorable, even if, usually, seizure control required high AED plasma levels. Since the clinical symptoms were not recognized early, some patients were treated only many years after the onset of symptoms. CONCLUSION: Among BMEI patients, our cases constitute a subgroup in which myoclonic jerks were always triggered by photostimulation, in particular at onset of their epilepsy.     

Absence seizures aggravated by valproic acid

PURPOSE: To report on pediatric patients with absence epilepsy who experienced absence seizure aggravation while receiving valproic acid (VPA). METHODS: The charts of all children from four pediatric epilepsy clinics receiving VPA for absence epilepsy were reviewed. Patients were evaluated and followed up between 1994 and 2000. RESULTS: Eight cases (six boys) of absence seizure aggravation were detected. Mean age at seizure onset was 5.8 years (range, 3-12 years). Six patients had simple absence seizures, one had myoclonic absences, and one had absences with automatisms. The electroencephalogram in all cases depicted generalized 3-Hz spike-and-wave activities. All eight patients experienced an increase in the frequency of absence seizures within days of VPA introduction. Dose increments resulted in further seizure aggravation. Serum levels of VPA were within therapeutic range in all patients. No case was attributed to VPA-induced encephalopathy. All patients improved on VPA discontinuation. In five children, VPA was reintroduced, resulting in further seizure aggravation. CONCLUSIONS: VPA can occasionally provoke absence seizure aggravation in patients with absence epilepsy.     

Benign myoclonic epilepsy in infants: electroclinical features and long-term follow-up of 34 patients

PURPOSE: Benign myoclonic epilepsy in infants (BMEI) is a rare epileptic syndrome characterized only by generalized myoclonic seizures (MSs) in normal children during the first 2 years. Our aim was to assess the electroclinical features and the follow-up of this syndrome. METHODS: BMEI was confirmed by electroencephalogram (EEG) in four neuropediatric units in France between 1981 and 2002. Clinical and electroencephalographic findings at diagnosis and during the follow-up were collected. The Vineland scale or Wechsler scale or both were used to perform neuropsychological evaluations. RESULTS: We report 34 patients with BMEI characterized by MSs occurring many times a day. The ictal EEG showed a generalized discharge of polyspikes, polyspikes-and-waves, or spikes-and-waves. The interictal EEG was usually normal. A family history of febrile seizures (FSs) or epilepsy was noted in six patients. A history of FSs was noted in 11 patients. Eleven patients had reflex MSs. Monotherapy with valproic acid was effective in 23 of 30 treated patients. The onset of epilepsy was known in all patients. Four patients had seizures after the initial symptoms. Juvenile myoclonic epilepsy developed in two patients, and cryptogenic partial epilepsy in another. Neuropsychological outcome was evaluated in 20 patients (10 with Wechsler scales and 17 with the Vineland scale). Cognitive functions were normal in 17 patients, whereas developmental delay was observed in three others. CONCLUSIONS: BMEI is clinically characterized by myoclonic seizures involving the upper part of the body, occurring many times a day. The ictal EEG showed a generalized discharge of polyspikes, polyspikes-and-waves, or spikes-and-waves. The interictal EEG was usually normal. Reflex MSs were frequently observed, suggesting that two distinctive syndromes are not necessary. BMEI may be followed by juvenile myoclonic epilepsy. Despite a generally favorable neuropsychological outcome, mental retardation can be observed more frequently than in the general population.     

Some clinical and EEG aspects of benign juvenile myoclonic epilepsy

Twelve patients with benign juvenile myoclonic epilepsy (BJME) representing 4% of our population of epileptics (n = 275) are presented. Only two patients (17%) had myoclonic jerks as the only seizure type. Seven (58%) had generalized tonic-clonic seizures (GTCS) and myoclonus. Three patients (25%) had absence seizures (AS), GTCS, and myoclonic jerks. Electroencephalographic evidence of photosensitivity was found in four (33%). Auditory precipitation of seizures was found in one patient. As is the case with other primary generalized epilepsies, the onset of BJME seems to be age specific. In our series the mean age of onset in years was 4.3 for AS, 14.75 for myoclonic jerks, and 16.4 for GTCS. It took an average of 8.5 years from the onset of BJME (range, 2-20 years) and 6.5 years from the onset of GTCS (range, 2 months-6 years) until the condition was properly recognized. Five patients experienced at least one episode of myoclonic status epilepticus. Generalized, paroxysmal, symmetric polyspike and slow wave discharges are the typical EEG finding. These complexes, however, showed considerable interpatient variability. Sleep deprivation proved to be the most valuable activating procedure. Valproic acid monotherapy effectively controlled myoclonic jerks as well as associated GTCS in most patients.     

Improvement of intractable childhood epilepsy following acute viral infection

In this study, we report 11 patients with intractable childhood epilepsy that improved following acute viral infection. The patients were 8 boys and 3 girls. Six of the 11 children were diagnosed as West syndrome (5 of the symptomatic type and 1 of the cryptogenic type). The remaining 5 children were myoclonic seizures. The patients became seizure free within 6 days following acute viral infections without an exchange or addition of antiepileptic drugs (AEDs). The types of acute viral infections were Exanthema subitum (Roseola infantum) in 5 patients, Rotavirus gastroenteritis in 2 patients, Measles infection in 2 patients, Herpetic stomatitis in 1 patient and Common cold in the remaining patient. Salaam seizures and/or tonic spasms disappeared within 6 days after the onset of viral infections, and hypsarrhythmia evolved to localized spikes on electroencephalography (EEG) in the patients with West syndrome. Epileptic seizures disappeared rapidly and EEG gradually normalized or improved in patients with myoclonic seizures. Four patients became seizure free for 5 years to 20 years. In 6 patients, seizures relapsed within 14 days to 1 month after the disappearance of seizures. One child remained seizure free for 12 months after viral infection. Common factors in 4 children who were continuously seizure free include (1) normal or almost normal findings of brain CT/MRI, (2) normal development prior to the onset of epileptic seizures, and (3) a short time interval between the onset of seizures and the acute viral infection. We propose several hypotheses including an immunological effect for the improvement of intractable childhood epilepsy following acute viral infection. Further study may provide important information concerning the mechanism of seizure control and the applicable to treatment for intractable childhood epilepsy.     

Myoclonic epileptic seizures during clozapine treatment: a report of three cases

Summary Three adult schizophrenic patients without a previous history of epilepsy are reported who, during clozapine treatment, developed paroxysmal EEG patterns and generalized myoclonic jerks without alteration of consciousness. These seizures were phenomenologically identical to those occurring in juvenile myoclonic epilepsy and were classified as generalized epileptic seizures. We tentatively conclude that generalized myoclonic epileptic seizures may be induced by clozapine.     

Juvenile Myoclonic Epilepsy: Factors of Error Involved in the Diagnosis and Treatment

Juvenile myoclonic epilepsy (JME), a common form of idiopathic generalized epilepsy, has a distinct clinical and electroencephalographic profile. Often JME is not recognized, with serious consequences on the sufferers. We examined factors contributing to the missed diagnosis even in an epilepsy clinic. Of 70 JME patients, 66 (91.4%) were not diagnosed on referral and 22 (33%) were not initially recognized in the epilepsy clinic. The correct diagnosis was established after a mean of 8.3 +/- 5.5 years from disease onset and an interval of 17.7 +/- 10.4 months from first evaluation in the epilepsy clinic. Myoclonic jerks, the hallmark of the disease, were not usually reported by patients. Similarly, relevant questioning may not be included in the history. Absence seizures antedating jerks by many years, myoclonic jerks reported as unilateral, generalized tonic-clonic seizures occurring during sleep and focal EEG abnormalities are other factors contributing to not recognizing JME. Our study reemphasizes the need to have not only a correct seizure diagnosis but also a correct epilepsy-disease diagnosis.     

Predictors for long-term seizure outcome in juvenile myoclonic epilepsy: 25-63 years of follow-up

Purpose: The long‐term seizure outcome of juvenile myoclonic epilepsy (JME) is still controversial; the value of factors that are potentially predictive for seizure outcome remains unclear. The aim of this study was both to investigate the long‐term seizure outcome in patients with JME after a follow‐up of at least 25 years and to identify factors that are predictive for the seizure outcome. Methods: Data from 31 patients (19 women) with JME were studied. All of them had a follow‐up of at least 25 years (mean 39.1 years) and were reevaluated with a review of their medical records and direct telephone or face‐to‐face interview. Key Findings: Of 31 patients 21 (67.7%) became seizure‐free; in six of them (28.6%) antiepileptic drug (AED) treatment was discontinued due to seizure freedom. The occurrence of generalized tonic–clonic seizures (GTCS) preceded by bilateral myoclonic seizures (BMS) (p = 0.03), a long duration of epilepsy with unsuccessful treatment (p = 0.022), and AED polytherapy (p = 0.023) were identified as significant predictors for a poor long‐term seizure outcome, whereas complete remission of GTCS under AED significantly increased the chance for complete seizure freedom (p = 0.012). The occurrence of photoparoxysmal responses significantly increases the risk of seizure recurrence after AED discontinuation (p = 0.05). Significance: This study shows conclusively that JME is a heterogeneous epilepsy syndrome. Life‐long AED treatment is not necessarily required to maintain seizure freedom. Several long‐term outcome predictors that can potentially increase the ability of clinicians and their confidence to recommend different treatment options to patients with JME were identified.     

Idiopathic Generalized Epilepsies Imitating Focal Epilepsies

Summary:  Classification of epileptic seizures and epilepsy syndromes as either focal or generalized is a fundamental and early part in the diagnostic process and is generally fairly easily accomplished. However, in patients with idiopathic generalized epilepsies, seizure and EEG features may suggest, particularly to the unwary, the occurrence of focal rather than generalized seizures. Misinterpretation of typical absence seizures as focal seizures, especially as temporal lobe seizures and of myoclonic seizures as focal clonic seizures, is a relatively common error and focal features during generalized tonic–clonic seizures may also be quite common. Sequences of seizures in idiopathic generalized epilepsies (such as absences or jerks followed by generalized tonic–clonic seizures) may also cause confusion. Versive and circling seizures are seizure types whose ictal semiology is clearly focal; nevertheless such seizures are described in idiopathic generalized epilepsies accompanied by generalized EEG discharges. The occurrence of focal EEG abnormalities in certain idiopathic generalized epilepsy syndromes is common. This is best known in juvenile myoclonic epilepsy.     

Clinical and EEG Asymmetries in Juvenile Myoclonic Epilepsy

Summary: We reviewed records of 85 patients with juvenile myoclonic epilepsy (JME) for significant asymmetries in clinical seizures or the EEG. We noted asymmetries in 26 of 85 patients (30.6%). Only 2 patients had both clinical and EEG asymmetries; 12 had clinical asymmetries and 12 had EEG asymmetries exclusively. Analysis of patients with and without asymmetries showed no statistically significant differences in comparisons of sex, age at seizure onset, family history of epilepsy, seizure type, or response to treatment. The delay in diagnosis was greater in JME patients with asymmetries (9.5 years) than in JME patients with no asymmetries (7.5 years), but this difference was not statistically significant. Fourteen of the 26 patients with asymmetries (53.8%) were initially misdiagnosed as having partial seizures. Asymmetries in JME patients are not only common, but are also a frequent cause of misdiagnosis.