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Seminars in Neurology Jun 2015The progressive myoclonus epilepsies (PMEs) comprise a group of rare and heterogeneous disorders defined by the combination of action myoclonus, epileptic seizures, and... (Review)
Review
The progressive myoclonus epilepsies (PMEs) comprise a group of rare and heterogeneous disorders defined by the combination of action myoclonus, epileptic seizures, and progressive neurologic deterioration. Neurologic deterioration may include progressive cognitive decline, ataxia, neuropathy, and myopathy. The gene defects for the most common forms of PME (Unverricht-Lundborg disease, Lafora disease, several forms of neuronal ceroid lipofuscinoses, myoclonus epilepsy with ragged-red fibers [MERRF], and type 1 and 2 sialidoses) have been identified. The prognosis of a PME depends on the specific disease. Lafora disease, the neuronal ceroid lipofuscinoses, and the neuronopathic form of Gaucher disease have an invariably fatal course. In contrast, Unverricht-Lundborg disease has a much slower progression, and with adequate care many patients have a normal life span. The specific diseases that cause PME are diagnosed by recognition of their age of onset, the associated clinical symptoms, the clinical course, the pattern of inheritance, and by special investigations such as enzyme measurement, skin/muscle biopsy, or gene testing.
Topics: Humans; Myoclonic Epilepsies, Progressive; Nervous System Diseases
PubMed: 26060909
DOI: 10.1055/s-0035-1552620 -
Seizure Aug 2021Epileptic syndromes are well-defined conditions comprising particular clinical features [seizure types, age of onset, response to treatment] and characteristic... (Review)
Review
Epileptic syndromes are well-defined conditions comprising particular clinical features [seizure types, age of onset, response to treatment] and characteristic electroencephalographic changes, while their etiology and subsequent prognosis may vary. The recognition of these syndromes is fundamental for pediatric neurology practice, representing an essential learning topic in this field. Nevertheless, many epileptic syndromes are still quite unfamiliar to students, residents and even neurologists, because of their low incidence and their minimal representation in the literature. This narrative review discusses the concept of epileptic syndromes and revisits seven lesser-known or uncommon syndromes in order to summarize their core clinical features, which can become important clues for daily neurological practice, namely epilepsy of infancy with migrating focal seizures, myoclonic epilepsy of infancy, self-limited infantile epilepsy, myoclonic encephalopathy in nonprogressive disorders, Jeavons syndrome, and epilepsy with myoclonic absences.
Topics: Child; Electroencephalography; Epilepsies, Myoclonic; Epilepsy, Reflex; Epileptic Syndromes; Humans; Incidence
PubMed: 34023208
DOI: 10.1016/j.seizure.2021.05.005 -
Medicina 2019Epileptic encephalopathies is a group of epileptic syndromes characterized by progressive cognitive impairment beyond the expected for the epilepsy activity. They are... (Review)
Review
Epileptic encephalopathies is a group of epileptic syndromes characterized by progressive cognitive impairment beyond the expected for the epilepsy activity. They are characterized by severe pharmaco-resistant epilepsy, severely abnormal electroencephalograms, early-age onset, neurocognitve impairment, variable phenotype and usually normal brain MRI. These syndromes are usually genetically determined. A correct and timely diagnosis could help and guide the medical counselling and the correct therapeutic approach improving the short, medium and long term outcomes. In this article we review the electroencephalographic and genetic findings along with the most recommended therapeutic options facilitating the clinical management. We include the following epileptic encephalopathy syndromes: Ohtahara, early myoclonic encephalopathy, epilepsy of infancy with migrating focal seizures, West, Dravet, non-progressive myoclonic status, Doose, Lennox-Gastaut, Landau-Kleffner and continuous spike-wave during sleep epilepsy.
Topics: Anticonvulsants; Brain Diseases; Electroencephalography; Epilepsies, Myoclonic; Humans; Spasms, Infantile; Syndrome
PubMed: 31603843
DOI: No ID Found -
Epilepsy & Behavior : E&B May 2018Angelman syndrome (AS) is a neurogenetic imprinting disorder caused by loss of the maternally inherited Ube3a gene and is characterized by generalized epilepsy, limited...
Angelman syndrome (AS) is a neurogenetic imprinting disorder caused by loss of the maternally inherited Ube3a gene and is characterized by generalized epilepsy, limited expressive speech, sleep dysfunction, and movement disorders. Myoclonic seizures are often the first seizure type to appear, and myoclonic status, associated with developmental regression, may occur in the first few years of life. Additionally, there have been rare reports of prolonged episodes of myoclonus without electrographic correlate in adults with AS. The medical records of 200 individuals seen in the Angelman Syndrome Clinic at the Massachusetts General Hospital and the Lurie Center for Autism were retrospectively reviewed to identify and characterize myoclonic seizures and episodes of nonepileptic myoclonus. Myoclonic seizures were reported in 14% of individuals with age of onset occurring before 8years. These are brief events, unless the individual was experiencing myoclonic status, and electroencephalographs show interictal generalized spike and wave activity. Nonepileptic myoclonus occurred in 40% of individuals over 10years of age, and prevalence appears to increase with age. The episodes of nonepileptic myoclonus arise during puberty or later, with age of onset ranging from 10 to 26years. These events were captured on 5 video electroencephalographs and had no electrographic correlate. They can last from seconds to hours, always occurring in the hands and spreading to the face and all extremities in some individuals. Episodes of nonepileptic myoclonus have a discrete beginning and end, lacks a postictal period, and are not associated with significant alteration of consciousness or developmental regression. These episodes can be difficult to treat and are often refractory to medication; however, levetiracetam, clobazam, and clonazepam appear to be effective for some individuals. Myoclonic seizures are common in AS, typically occurring in young children and associated with epileptiform changes on electroencephalographs. Prolonged episodes are associated with developmental regression. In contrast, nonepileptic myoclonus typically begins in adolescence or early adulthood and has no electroencephalogram (EEG) correlate, alteration in consciousness, or regression but can significantly impact quality of life.
Topics: Adolescent; Adult; Age Distribution; Angelman Syndrome; Anticonvulsants; Child; Child, Preschool; Electroencephalography; Epilepsies, Myoclonic; Female; Humans; Infant; Male; Prevalence; Quality of Life; Retrospective Studies; Seizures; Sleep Wake Disorders; Young Adult
PubMed: 29555100
DOI: 10.1016/j.yebeh.2018.02.006 -
Arquivos de Neuro-psiquiatria May 2022Cannabidiol (CBD) has become a promising therapeutic option in the treatment of epilepsy. Recent studies provide robust evidence that CBD is effective and safe.... (Review)
Review
BACKGROUND
Cannabidiol (CBD) has become a promising therapeutic option in the treatment of epilepsy. Recent studies provide robust evidence that CBD is effective and safe. Limitations in current knowledge and regulatory issues still limit CBD use. CBD use regarding epilepsy types still lacks clear guidelines.
OBJECTIVE
To critically review the main current pharmacological features and clinical issues regarding CBD use in epilepsy, to provide current regulatory background regarding CBD use in Brazil, and to suggest a practical CBD therapeutic guide in Brazil.
METHODS
Non-systematic literature review (up to February 2022) of current concepts of CBD and epilepsy, including the authors' personal experience.
RESULTS
Five pivotal trials have led to CBD approval as an adjunctive treatment for Dravet and Lennox-Gastaut syndromes, and for the tuberous sclerosis complex. Efficacy of CBD in other drug-resistant epilepsies remains not completely understood. CBD adverse event profile and drug interactions are better understood. CBD is well tolerated. In Brazil, CBD is not classified as a medication, but as a product subject to a distinct regulatory legislation. CBD is still not offered by the National Brazilian health system, but can be purchased in authorized pharmacies or imported under prescription and signed informed consent.
CONCLUSION
CBD is a recognized novel treatment for epilepsy. Future well-designed studies and public health strategies are needed to offer widespread access to CBD, and to improve the quality of life of people living with epilepsy in Brazil.
Topics: Anticonvulsants; Brazil; Cannabidiol; Epilepsies, Myoclonic; Epilepsy; Humans; Quality of Life
PubMed: 35976327
DOI: 10.1590/0004-282X-ANP-2022-S137 -
Seizure Jul 2018Tap seizure is a type of reflex myoclonic epilepsy in which seizures are evoked mainly by unexpected tactile stimuli and which is classified among the electroclinical... (Review)
Review
Tap seizure is a type of reflex myoclonic epilepsy in which seizures are evoked mainly by unexpected tactile stimuli and which is classified among the electroclinical syndromes of infancy. This condition, whose onset is in the first two years of life, is characterized by excellent prognosis and is extremely rare. We reviewed all published articles and case reports on Reflex Myoclonic Epilepsies focusing on touch-induced seizures in order to clarify clinical and electroencephalographic findings. Our aim is to increase knowledge about this specific disorder in order to help pediatricians avoid extensive investigations when making their diagnosis and reassure parents regarding absence of long-term complications.
Topics: Brain; Epilepsy, Reflex; Humans; Infant; Myoclonic Epilepsy, Juvenile; Seizures; Touch
PubMed: 29727740
DOI: 10.1016/j.seizure.2018.04.013 -
Seizure Jul 2023The late onset myoclonic epilepsy in Down Syndrome (LOMEDS) is a peculiar epilepsy type characterized by cortical myoclonus and generalized tonic-clonic seizures (GTCS),... (Review)
Review
INTRODUCTION
The late onset myoclonic epilepsy in Down Syndrome (LOMEDS) is a peculiar epilepsy type characterized by cortical myoclonus and generalized tonic-clonic seizures (GTCS), in people suffering from cognitive decline in Down syndrome (DS). In this review, we analyzed available data on the diagnostic and therapeutic management of individuals with LOMEDS.
METHODS
We performed a systematic search of the literature to identify the diagnostic and therapeutic management of patients with LOMEDS. The following databases were used: PubMed, Google Scholar, EMBASE, CrossRef. The protocol was registered on PROSPERO (registration code: CRD42023390748).
RESULTS
Data from 46 patients were included. DS was diagnosed according to the patient's clinical and genetic characteristics. Diagnosis of Alzheimer's dementia (AD) preceded the onset of epilepsy in all cases. Both myoclonic seizures (MS) and generalized tonic-clonic seizures (GTCS) were reported, the latter preceding the onset of MS in 28 cases. EEG was performed in 45 patients, showing diffuse theta/delta slowing with superimposed generalized spike-and-wave or polyspike-and-wave. A diffuse cortical atrophy was detected in 34 patients on neuroimaging. Twenty-seven patients were treated with antiseizure medication (ASM) monotherapy, with reduced seizure frequency in 17 patients. Levetiracetam and valproic acid were the most used ASMs. Up to 41% of patients were unresponsive to first-line treatment and needed adjunctive therapy for seizure control.
CONCLUSIONS
AD-related pathological changes in the brain may play a role in LOMEDS onset, although the mechanism underlying this phenomenon is still unknown. EEG remains the most relevant investigation to be performed. A significant percentage of patients developed a first-line ASM refractory epilepsy. ASMs which modulate the glutamatergic system may represent a good therapeutic option.
Topics: Humans; Down Syndrome; Epilepsy; Epilepsies, Myoclonic; Levetiracetam; Seizures; Alzheimer Disease; Electroencephalography; Anticonvulsants; Epilepsy, Generalized
PubMed: 37267668
DOI: 10.1016/j.seizure.2023.05.017 -
Epilepsia Mar 2024KCTD7-related progressive myoclonic epilepsy (PME) is a rare autosomal-recessive disorder. This study aimed to describe the clinical details and genetic variants in a...
OBJECTIVE
KCTD7-related progressive myoclonic epilepsy (PME) is a rare autosomal-recessive disorder. This study aimed to describe the clinical details and genetic variants in a large international cohort.
METHODS
Families with molecularly confirmed diagnoses of KCTD7-related PME were identified through international collaboration. Furthermore, a systematic review was done to identify previously reported cases. Salient demographic, epilepsy, treatment, genetic testing, electroencephalographic (EEG), and imaging-related variables were collected and summarized.
RESULTS
Forty-two patients (36 families) were included. The median age at first seizure was 14 months (interquartile range = 11.75-22.5). Myoclonic seizures were frequently the first seizure type noted (n = 18, 43.9%). EEG and brain magnetic resonance imaging findings were variable. Many patients exhibited delayed development with subsequent progressive regression (n = 16, 38.1%). Twenty-one cases with genetic testing available (55%) had previously reported variants in KCTD7, and 17 cases (45%) had novel variants in KCTD7 gene. Six patients died in the cohort (age range = 1.5-21 years). The systematic review identified 23 eligible studies and further identified 59 previously reported cases of KCTD7-related disorders from the literature. The phenotype for the majority of the reported cases was consistent with a PME (n = 52, 88%). Other reported phenotypes in the literature included opsoclonus myoclonus ataxia syndrome (n = 2), myoclonus dystonia (n = 2), and neuronal ceroid lipofuscinosis (n = 3). Eight published cases died over time (14%, age range = 3-18 years).
SIGNIFICANCE
This study cohort and systematic review consolidated the phenotypic spectrum and natural history of KCTD7-related disorders. Early onset drug-resistant epilepsy, relentless neuroregression, and severe neurological sequalae were common. Better understanding of the natural history may help future clinical trials.
Topics: Adolescent; Child; Child, Preschool; Humans; Infant; Young Adult; Electroencephalography; Epilepsies, Myoclonic; Myoclonic Epilepsies, Progressive; Potassium Channels; Seizures; Unverricht-Lundborg Syndrome
PubMed: 38231304
DOI: 10.1111/epi.17880 -
The Canadian Journal of Neurological... Jun 2016Dravet syndrome is one of the most severe epilepsy syndromes of early childhood, and it comes with very high morbidity and mortality. The typical presentation is... (Review)
Review
Dravet syndrome is one of the most severe epilepsy syndromes of early childhood, and it comes with very high morbidity and mortality. The typical presentation is characterized by hemiclonic or generalized clonic seizures triggered by fever during the first year of life, followed by myoclonic, absence, focal and generalized tonic-clonic seizures. Non-convulsive status epilepticus and epileptic encephalopathy are common. Development is normal in the first year of life, but most individuals eventually suffer from intellectual impairment. Dravet syndrome is associated with mutations in the sodium channel alpha1 subunit gene (SCN1A) in 70-80% of individuals. SCN1A mutation results in inhibition of the GABAergic inhibitory interneurons, leading to excessive neuronal excitation. The "interneuron hypothesis" is the current most accepted pathophysiological mechanism of Dravet syndrome. The mortality rate is increased significantly in Dravet syndrome. Ataxia, a characteristic crouched gait and Parkinson's symptoms may develop in some individuals. It is likely that Dravet syndrome is underdiagnosed in adults with treatment-resistant epilepsy. Early diagnosis is important to avoid anti-seizure medications that exacerbate seizures.
Topics: Animals; Epilepsies, Myoclonic; Humans; Mutation; NAV1.1 Voltage-Gated Sodium Channel
PubMed: 27264139
DOI: 10.1017/cjn.2016.243 -
Clinical Neurophysiology : Official... Apr 2021To further delineate the electroclinical features of individuals with SYNGAP1 pathogenic variants.
OBJECTIVE
To further delineate the electroclinical features of individuals with SYNGAP1 pathogenic variants.
METHODS
Participants with pathogenic SYNGAP1 variants and available video-electroencephalogram (EEG) recordings were recruited within five European epilepsy reference centers. We obtained molecular and clinical data, analyzed EEG recordings and archived video-EEGs of seizures and detailed characteristics of interictal and ictal EEG patterns for every patient.
RESULTS
We recruited 15 previously unreported patients and analyzed 72 EEGs. Two distinct EEG patterns emerged, both triggered by eye closure. Pattern 1 (14/15 individuals) consisted of rhythmic posterior/diffuse delta waves appearing with eye-closure and persisting until eye opening (strongly suggestive of fixation-off sensitivity). Pattern 2 (9/15 individuals) consisted of diffuse polyspike-and-wave discharges triggered by eye closure (eye-closure sensitivity). Both patterns presented in 8/15. Including archived video-EEG clips of seizures from 9/15 patients, we analyzed 254 seizures. Of 224 seizures experienced while awake, 161 (72%) occurred at or following eye closure. In 119/161, pattern 1 preceded an atypical absence, myoclonic seizure or myoclonic absence; in 42/161, pattern 2 was associated with eyelid myoclonia, absences and myoclonic or atonic seizures.
CONCLUSIONS
Fixation-off and eye closure were the main triggers for seizures in this SYNGAP1 cohort.
SIGNIFICANCE
Combining these clinical and electroencephalographic features could help guide genetic diagnosis.
Topics: Adolescent; Brain; Child; Child, Preschool; Electroencephalography; Epilepsies, Myoclonic; Epilepsy, Reflex; Female; Humans; Infant; Male; ras GTPase-Activating Proteins
PubMed: 33639450
DOI: 10.1016/j.clinph.2021.01.014