Doose Syndrome Research Articles

Myoclonic astatic epilepsy: An age-dependent epileptic syndrome with favorable seizure outcome but variable cognitive evolution

The objective of the study was to explore clinical, electroencephalography (EEG), neuropsychological features and prognosis of myoclonic-astatic epilepsy (MAE). Of 327 children aged between 1 and 9 years with a diagnosis of generalized epilepsy followed between 2000 and 2008, 18 (5.5%) had MAE. Male significantly predominated (88.9%). Age at onset ranged from 2.3 to 4.9 years (mean 3.6 years). Median follow-up period was 6.3 years. In addition to myoclonic-astatic seizures patients had myoclonic seizures (66.7%), drop attacks (72.2%), head drops (77.8%) absences (88.9%), tonic-clonic generalized seizure (77.8%), tonic seizures (38.9%), non-convulsive status epilepticus (16.7%). Seven patients (38.9%) had an epileptic encephalopathy. At onset, interictal epileptiform and slow abnormalities were recorded, respectively, in 100% and 77.8% of patients. EEG abnormalities disappeared in all patients within 4 years since the onset. At long-term follow-up, two patients developed focal abnormalities typical of rolandic epilepsy and two patients photosensitivity. On neuropsychological testing 66.7% of patients had a normal IQ (mean 81.2±17.0, range 47-105, median 84.5) after a mean period of 4.4 years since the last seizure. Sixteen out of 18 patients remitted within 3.5 years since the onset and in two patients tonic seizures persisted. MAE is generalized childhood epilepsy: although cognitive functions might deteriorate, outcome is good regarding seizures.

A retrospective population‐based study on seizures related to childhood vaccination

Cases of severe childhood epilepsies in temporal association with vaccination have great impact on the acceptance of vaccination programs by parents and health care providers. However, little is known about the type and frequency of seizures and epilepsy syndromes following vaccination. This study aims to describe the clinical features of children presenting with seizures after vaccination using a register-based cohort. We surveyed the national German database of adverse events following immunization (AEFI) for reported seizures and epilepsies in children aged 0-6 years. All cases reported in 2006-2008 were analyzed retrospectively; available clinical information was reevaluated and classified by seizure type and epilepsy syndrome. In total, 328 cases reported between 2006 and 2008 were included. Data supportive of seizures or epilepsy were present in 247 (75.3%) of 328 patients with a mean interval between the vaccination and the epileptic event of 24 h and 7.5 days for inactivated and attenuated vaccines, respectively. Fifty-one (15.5%) of 328 patients presented with syncope, hypotonic-hyporesponsive episodes, or other nonepileptic events. Information was insufficient for classification into epileptic versus nonepileptic events in 30 (11.3%) of 328 patients. For cases with confirmed seizures, febrile seizures were present in 121 (49%) of 247 cases, and 38 (15.4%) of 247 patients had single afebrile seizures. Status epilepticus was described in 21 (8.5%) of 247 patients. Thirty-one (12.6%) of 247 patients presented with various pediatric epilepsy syndromes. Severe childhood epilepsies (Dravet syndrome, West syndrome, Lennox-Gastaut syndrome, or Doose syndrome) were diagnosed in 29 (11.7%) of 247 patients, with the vaccination-associated event being the first documented seizure in 15 (51.7%) of 29 patients. Vaccination-associated seizures present in the setting of various epilepsy syndromes, including severe childhood epilepsies in >10% of cases. Early diagnosis of the corresponding epilepsy syndromes and confirmation of an underlying etiology is important for treatment decisions, genetic counseling, and public health evaluation of vaccine safety.

Myoclonic astatic epilepsy and the use of the ketogenic diet

Myoclonic astatic epilepsy (MAE) is a rare childhood generalized epilepsy syndrome of unknown incidence and etiology. Onset may be explosive with a myriad of different seizure types and children may become severely affected with an epileptic encephalopathy. This disorder may be particularly sensitive to the ketogenic diet (KD). This article will briefly review the background, diagnostic criteria's and our current information regarding the use of dietary therapies in MAE.

Glucose Transporter 1 Deficiency as a Treatable Cause of Myoclonic Astatic Epilepsy

To determine if a significant proportion of patients with myoclonic-astatic epilepsy (MAE) have glucose transporter 1 (GLUT1) deficiency. Genetic analysis. Ambulatory and hospitalized care. Eighty-four unrelated probands with MAE were phenotyped and SLC2A1 was sequenced and analyzed by multiplex ligation-dependent probe amplification. Any identified mutations were then screened in controls. Any SLC2A1 mutations. Four of 84 probands with MAE had a mutation of SLC2A1 on sequencing. Multiplex ligation-dependent probe amplification analysis did not reveal any genomic rearrangements in 75 of the remaining cases; 5 could not be tested. Two patients with MAE with SLC2A1 mutations also developed paroxysmal exertional dyskinesia in childhood. Five percent of our patients with MAE had SLC2A1 mutations, suggesting that patients with MAE should be tested for GLUT1 deficiency. Diagnosis of GLUT1 deficiency is a strong indication for early use of the ketogenic diet, which may substantially improve outcome of this severe disorder.

P08.5 Intractable myoclonic epilepsy, mental retardation and dysmorphic features in a boy with chromosomal aberration: 46XY. ish der(15)t(X;15)(p22.; q26.3)dn

Background: Mental retardation affects 2-3% of general population and genetic cause can be detected in around 5% of patients. Many of these patients also suffer from epilepsy. Aim of the study: We present 13 years old patient with de novo chromosomal aberation characterized by addition of Xp chromosome (partial trisomy) to terminal part of 15q chromosome associated with intractable myoclonic epilepsy, mental retardation and dysmorphic features. Methods: The boy is third child of healthy parents and has two healthy siblings. At the age of 6 months psychomotor retardation was noticed. He revealed numerous dysmorphic features: down-slanted palpebral fissures, hypertelorism, micrognatia, dysmorphic ears, clubbing fingers and genital malformations. At the age of 10 he developed intractable myoclonic-astatic epilepsy that resulted in frequent falls and injuries. At present he is moderately mentally retarded, has clumsy gait and his somatic development follows 5th percentile for height and weight, while he is normocephalic. Results: EEG recordings showed slower cerebral activity with diffuse paroxysmal discharges of high-voltage polyspike-wave complexes. MRI showed moderate dilation of lateral ventricles, small hyperintensive areas in peritrigonal white matter and depletion of white matter of dorsal corpus callosum. Standard karyotype revealed an excess of the Xp material attached to the terminal part of the 15q. FISH analysis performed by SHOX probe confirmed the excess of genetic material of Xp on 15q. Conclusion: Our presentation is additional contribution to genetic cause of mental retardation, dysmorphic features and intractable epilepsy, to our knowledge not described by now.

Management of Seizures in Lennox-Gastaut Syndrome

Lennox-Gastaut syndrome is an epilepsy syndrome that begins in childhood (between 1 and 8 years of age), worsens during latency and persists frequently into adulthood, is refractory to antiepileptic medications, and results in cognitive decline and behavioral problems in affected individuals. Seizure types consist primarily of axial tonic, atonic, and atypical absence; nocturnal tonic seizures are the most common seizure pattern in this population, but often are not one of the initial seizure patterns. Some patients also have myoclonic seizures; this seizure pattern is less frequent than the three preceding types. Although there are some cases that are cryptogenic, most are symptomatic, arising during prenatal and perinatal periods from intrauterine infections, and vascular insults to the brain. Examples of causes of Lennox-Gastaut syndrome include migrational abnormalities of the brain, late effects of CNS infections, certain genetic disorders such as tuberous sclerosis, and inherited metabolic disorders. The difficulty early in the course of Lennox-Gastaut syndrome is distinguishing this diagnosis from severe myoclonic epilepsy of infancy (Dravet syndrome) or from myoclonic-astatic epilepsy (Doose syndrome), as the seizure patterns in these three syndromes may overlap at the onset. EEG is a helpful diagnostic tool in the diagnosis of Lennox-Gastaut syndrome, usually demonstrating high voltage, bifrontal 1.5-2.5 Hz spike and wave complexes interictally, and attenuation with paroxysmal fast activity (10-13 Hz) during the ictal phase. Treatment options for Lennox-Gastaut syndrome have been less than optimal. In recent years, several drugs have been tested and approved for the treatment of this syndrome; these include felbamate, lamotrigine, topiramate, and rufinamide. The long-term outcome does not appear to be any better with the newer antiepileptic drugs than when using earlier prescribed antiepileptic drugs or polytherapy. Treatment options other than antiepileptic drugs include a ketogenic diet, vagus nerve stimulation, and corpus callosotomy. Long-term outcome of these patients relative to seizure control and cognition is poor. Most develop moderate intellectual disability within a few years of onset of the syndrome. Many develop behavioral problems with inattention, hyperactivity, and aggression.

One novel Dravet syndrome causing mutation and one recurrent MAE causing mutation in SCN1A gene

Mutations in SCN1A gene, encoding the voltage-gated sodium channel α1-subunit, are found to be associated with severe myoclonic epilepsy in infancy or Dravet syndrome (DS), but only rarely with the myoclonic astatic epilepsy (MAE, or Doose syndrome). We report on two patients with SCN1A mutations and severe epilepsy within the spectrum of generalized epilepsy with febrile seizures plus syndrome (GEFS+), the phenotypes being consistent with DS and MAE, respectively. Analysis of SCN1A revealed a heterozygous de novo frameshift mutation (c.4205_4208delGAAA) in the patient with DS, and a recurrent missense mutation (c.3521C > G) in that suffering from MAE. The missense mutation has been reported in patients with neurological diseases of various manifestations, which suggests that this variability is likely to result from the modifying effects of other genetic or environmental factors. DS phenotype has been mainly found associated with truncation mutations, while predominantly missense mutations and very few prematurely terminating substitutions have been reported in GEFS+ patients.

First observations of treatment with rufinamide in children with myoclonic-astatic epilepsy

Aims: We report about the add-on therapy of the orphan-drug rufinamide (RUF), which is licensed for Lennox-Gastaut-Syndrome in seven patients with difficult-to-treat Doose-Syndrome (=myoclonic-astatic epilepsy, MAE).

A prospective open-labeled trial with levetiracetam in pediatric epilepsy syndromes: Continuous spikes and waves during sleep is definitely a target

Although LVT is currently extensively prescribed in childhood epilepsy, its effect on the panel of refractory epilepsy syndromes has not been entirely evaluated prospectively. In order to study the efficacy and safety of LVT as adjunctive therapy according to syndromes, we included 102 patients with refractory seizures (6 months to 15 years) in a prospective open-labeled trial. The responder rate was respectively 36% and 32% at 3 and 6 months with 6% and 7% patients becoming seizure free. Among the responders at 6 months ( n = 33), seizure frequency decreased by 66% and 79% at 3 and 6 months LVT compared to baseline. The highest benefit was for CSWS patients with 2/3 responders, 50% seizure free and no aggravation. LVT provided respectively 39% and 42% responders in focal and absence epilepsies. Infantile spasms and Dravet syndrome experienced the lowest efficacy. No patient with myoclonic-astatic epilepsy or Lennox–Gastaut syndrome was aggravated. LVT dose over 40 mg/kg/d was associated with a lower response rate. Tolerability was excellent. In spite of a small sample, we assume that CSWS is a good candidate for a randomized-controlled trial with LVT.

Update on rufinamide in childhood epilepsy

Rufinamide is an orally active, structurally novel compound (1-[(2,6-difluorophenil1) methyl1]-1 hydro 1,2,3-triazole-4 carboxamide), which is structurally distinct from other anticonvulsant drugs. It was granted orphan drug status for the adjunctive treatment of Lennox-Gastaut syndrome (LGS) in the United States in 2004, and released for use in Europe in 2007. In January 2009, rufinamide was approved by the United States Food and Drug Administration for treatment of LGS in children 4 years of age and older. It is also approved for adjunctive treatment for partial seizures in adults and adolescents. Rufinamide’s efficacy mainly against atonic/tonic seizures in patients with LGS seems nowadays indubitable and has been confirmed both in randomized controlled trial and in open label extension studies. More recently, rufinamide was evaluated for the adjunctive treatment of childhood-onset epileptic encephalopathies and epileptic syndromes other than LGS, including epileptic spasms, multifocal epileptic encephalopathy with spasm/tonic seizures, myoclonic-astatic epilepsy, Dravet syndrome and malignant migrating partial seizures in infancy. This review updates the existing literature data on the efficacy and safety/tolerability of rufinamide in childhood-onset epilepsy syndromes.

Will seizure control improve by switching from the modified Atkins diet to the traditional ketogenic diet?

It has been reported that children can maintain seizure control when the ketogenic diet (KD) is transitioned to the less-restrictive modified Atkins diet (MAD). What is unknown, however, is the likelihood of additional seizure control from a switch from the MAD to the KD. Retrospective information was obtained from 27 patients who made this dietary change from four different institutions. Ten (37%) patients had ≥10% additional seizure reduction with the KD over the MAD, of which five became seizure-free. The five children who did not improve on the MAD failed to improve when transitioned to the KD. A higher incidence of improvement with the KD occurred for those with myoclonic-astatic epilepsy (70% vs. 12% for all other etiologies, p = 0.004), including all who became seizure-free. These results suggest that the KD probably represents a "higher dose" of dietary therapy than the MAD, which may particularly benefit those with myoclonic-astatic epilepsy.

Doose syndrome (myoclonic–astatic epilepsy): 40 years of progress

Doose syndrome, otherwise traditionally known as myoclonic-astatic epilepsy, was first described as a unique epilepsy syndrome by Dr Hermann Doose in 1970. In 1989, the International League Against Epilepsy classified it formally as a symptomatic generalized epilepsy, and 20 years later it was renamed 'epilepsy with myoclonic-atonic seizures'. In this review, we discuss the components of this unique disorder including its incidence, clinical features, and electroencephalographic findings. Recent evidence has suggested possible genetic links to the GEFS+ (generalized epilepsy with febrile seizures plus) family, and, additionally, some children with structural brain lesions can mimic the Doose syndrome phenotype. Treatment strategies such as corticosteroids, ethosuximide, and valproate have been described as only partially effective, but newer anticonvulsants, such as levetiracetam and zonisamide, may provide additional seizure control. The most effective treatment reported to date appears to be the ketogenic diet. Prognosis is quite varied in this disorder; however, many children can have a remarkably normal neurodevelopmental outcome.

Absence epilepsies with widely variable onset are a key feature of familial GLUT1 deficiency

Familial glucose transporter type 1 (GLUT1) deficiency due to autosomal dominant inheritance of SLC2A1 mutations is associated with paroxysmal exertional dyskinesia; epilepsy and intellectual disability occur in some family members. We recently demonstrated that GLUT1 deficiency occurs in over 10% of patients with early-onset absence epilepsy. This family study analyses the phenotypes in 2 kindreds segregating SLC2A1 mutations identified through probands with early-onset absence epilepsy. One comprised 9 individuals with mutations over 3 generations; the other had 6 individuals over 2 generations. Of 15 subjects with SLC2A1 mutations, epilepsy occurred in 12. Absence seizures were the most prevalent seizure type (10/12), with onset from 3 to 34 years of age. Epilepsy phenotypes varied widely, including idiopathic generalized epilepsies (IGE) with absence (8/12), myoclonic-astatic epilepsy (2/12), and focal epilepsy (2/12). Paroxysmal exertional dyskinesia occurred in 7, and was subtle and universally undiagnosed prior to molecular diagnosis. There were 2 unaffected mutation carriers. GLUT1 deficiency is an important monogenic cause of absence epilepsies with onset from early childhood to adult life. Individual cases may be phenotypically indistinguishable from common forms of IGE. Although subtle paroxysmal exertional dyskinesia is a helpful diagnostic clue, it is far from universal. The phenotypic spectrum of GLUT1 deficiency is considerably greater than previously recognized. Diagnosis of GLUT1 deficiency has important treatment and genetic counseling implications.

Efficacy of Felbamate in the Treatment of Intractable Pediatric Epilepsy

The antiepileptic drug felbamate has demonstrated efficacy against a variety of seizure types in the pediatric population, particularly seizures associated with Lennox-Gastaut syndrome. Postmarketing experience, however, revealed serious idiosyncratic adverse effects not observed during clinical trials, including aplastic anemia and liver failure. As a result, many physicians have been hesitant to prescribe felbamate. This retrospective study evaluated the efficacy of felbamate in a pediatric population with intractable epilepsy. Of 38 patients, 22 had Lennox-Gastaut syndrome (58%); 6 had myoclonic-astatic epilepsy of Doose (16%); 5 had symptomatic generalized epilepsy, not otherwise specified (13%); and 5 had symptomatic localization-related epilepsy (13%). Most patients had multiple seizure types and had been tried on a variety of antiepileptic medications. With felbamate treatment, 6 patients (16%) became seizure free, including 4 of the 6 patients with myoclonic-astatic epilepsy of Doose; 24 patients (63%) had a greater than 50% reduction in seizure frequency. In this population felbamate appeared to be safe, with minimal adverse effects. The study is limited by the small number of patients and by its retrospective nature, but nonetheless adds to the evidence that felbamate is an important antiepileptic drug for medically refractory epilepsy in children and is well tolerated with few adverse effects.

Genetics of the epilepsies: Genetic twists in the channels and other tales

Genetics of the epilepsies: Genetic twists in the channels and other tales

Generalized Epilepsy With Febrile Seizures plus: Novel SCN1A Mutation

Genetic generalized epilepsy with febrile seizures plus (GEFS+) is an idiopathic generalized epileptic syndrome of heterogeneous phenotype. The cases described here are of two brothers, one with severe myoclonic epilepsy of infancy (Dravet syndrome) and the other myoclonic-astatic epilepsy. Their father experienced one simple febrile seizure in infancy and two generalized tonic-clonic seizures after head trauma in adulthood, and had generalized epileptiform activity in the electroencephalogram. He died in a severe sport accident before genetic testing could be performed. In both siblings, but not in their healthy mother, DNA analysis identified an unreported point mutation (c.3925 C>T) in exon 20 of the SCN1A gene. The missense mutation was therefore assumed to be inherited from the father, who had a very mild clinical picture, with a single febrile seizure and only occasional generalized tonic-clonic seizures. The offspring have GEFS+ phenotypes with opposite severity, an illustration of the broad intrafamilial variability of SCN1A gene mutations.

Ketogenic diet and epilepsy: an up-date review

Background and Aims: Ketogenic diet is currently a therapeutic option for the treatment of epilepsy other than anticonvulsant drugs, for which there is a growing interest in Europe and worldwide, mainly due to the persisting number of refractory patients and the adverse side effects of antiepileptic old and new drugs. Aim of the present article is to review literature data regarding the use of the diet in the different types of epilepsies and epilepsy syndromes, trying to better understand the main evidence-based indications for its use. Material and Methods: A literature search was based on a Medline search of published retrospective, not-controlled prospective and randomized controlled trials on the use of the ketogenic diet for the treatment of epilepsies and antiepileptic encephalopathies. In some instances, case reports were also included. A search on standard textbooks and review articles on the use of the ketogenic diet was considered as well. A summary and a critical appraisal of what emerged from the literature for each epileptic syndrome will be discussed in this review.Conclusions: Ketogenic diet is considered as the primary treatment of GLUT-1 deficiency syndrome and pyruvate-dehydrogenase deficiency. It is so far included as secondary option for the so called a€A“catastrophic epileptic encephalopaties of childhooda€, and should be a potential treatment against a wide variety of other seizure types and epilepsy syndromes as well as many symptomatic localization-related epilepsies. The best evidence of its efficacy regards refractory infantile spasms, Dravet syndrome and myoclonic-astatic epilepsy as well as epileptic encephalopathies due to cortical migration disorders. There is also a growing interest for dietary treatments for epilepsy other than ketogenic diet, such as the modified Atkins diet and the low glicemic index diet , both providing a daily amount of fat less than the ketogenic diet. Presently, some authors prefer to use the ketogenic diet in infants and younger children, leaving the other two diets for the treatment of older children, adolescents and young adults.

Managing Severe Epilepsy Syndromes of Early Childhood

Managing severe epilepsy syndromes of early childhood is challenging as the seizures are typically resistant to treatment and may cause disabling mental and behavioral problems in later life. A comprehensive treatment plan includes pharmacologic, nonpharmacologic, and surgical options. This article reviews clinical studies examining the efficacies of antiepileptic medications in reducing seizure frequency in Dravet syndrome, Doose syndrome, and Lennox-Gastaut syndrome. The benefits of the ketogenic diet for children with these severe epilepsies, together with the advantages of vagus nerve stimulation and corpus callosotomy in those patients with Lennox-Gastaut syndrome, are also discussed. Special treatment considerations for each syndrome are also highlighted to improve the management of patients with these syndromes.

Epileptic negative drop attacks in atypical benign partial epilepsy: a neurophysiological study

We conducted a computer-assisted polygraphic analysis of drop attacks in a child with atypical benign partial epilepsy (ABPE) to investigate neurophysiological characteristics. The patient was a six-year two-month-old girl, who had started to have focal motor seizures, later combined with daily epileptic negative myoclonus (ENM) and drop attacks, causing multiple injuries. We studied episodes of ENM and drop attacks using video-polygraphic and computer-assisted back-averaging analysis. A total of 12 ENM episodes, seven involving the left arm (ENMlt) and five involving both arms (ENMbil), and five drop attacks were captured for analysis. All episodes were time-locked to spike-and-wave complexes (SWC) arising from both centro-temporo-parietal (CTP) areas. The latency between the onset of SWC and ENMlt, ENMbil, and drop attacks reached 68 ms, 42 ms, and 8 ms, respectively. The height of the spike as well as the slow-wave component of SWC for drop attacks were significantly larger than that for both ENMlt and ENMbil (p < 0.05). Drop attacks were considered to be epileptic negative myoclonus involving not only upper proximal but also axial muscles, causing the body to fall. Thus, drop attacks in ABPE are considered to be epileptic negative drop attacks arising from bilateral CTP foci and differ from drop attacks of a generalized origin seen in Lennox-Gastaut syndrome and myoclonic-astatic epilepsy.

Two novelCLCN2mutations accelerating chloride channel deactivation are associated with idiopathic generalized epilepsy

Heterozygous mutations in the CLCN2 gene encoding the voltage-gated chloride channel CLC2 have been identified in patients with idiopathic generalized epilepsy (IGE). Yet the involvement of CLCN2 in epilepsy remains controversial. To investigate the involvement of CLCN2 in another independent sample, we screened 52 unrelated patients from IGE families and 23 patients with Doose syndrome for mutations in CLCN2. No mutations were found in patients with Doose syndrome. In three unrelated IGE families, we identified two novel missense mutations, p.Arg235Gln and p.Arg577Gln, which were absent in large ethnically-matched control populations, and one novel p.Arg644Cys variant, which was also found in five Indian controls. Functional characterization of mutant channels using heterologous expression in mammalian cells and whole-cell patch-clamp recordings revealed faster deactivation kinetics as the major phenotype of both missense mutations. This finding predicts a loss of function that may contribute to intracellular chloride accumulation or neuronal hyperexcitability. However, the incomplete segregation of the mutations among affected members and the transmission by unaffected parents suggests that these CLCN2 mutations alone are not sufficient to induce epilepsy. They may instead represent susceptibility factors among other so far undetected genetic alterations in the respective families.