A novel somatic mutation in GNB2 provides new insights to the pathogenesis of Sturge-Weber syndrome.

Sturge-Weber syndrome (SWS) is a neurocutaneous disorder characterized by vascular malformations affecting skin, eyes and leptomeninges of the brain, which can lead to glaucoma, seizures and intellectual disability. The discovery of a disease-causing somatic missense mutation in the GNAQ gene, encoding an alpha chain of heterotrimeric G-proteins, has initiated efforts to understand how G-proteins contribute to SWS pathogenesis. The mutation is predominantly detected in endothelial cells and is currently believed to affect downstream MAPK signalling. In this study of six Norwegian patients with classical SWS, we aimed to identify somatic mutations through deep sequencing of DNA from skin biopsies. Surprisingly, one patient was negative for the GNAQ mutation, but instead harbored a somatic mutation in GNB2 (NM_005273.3:c.232A>G, p.Lys78Glu), which encodes a beta chain of the same G-protein complex. The positions of the mutant amino acids in the G-protein are essential for complex reassembly. Therefore, failure of reassembly and continuous signalling is a likely consequence of both mutations. Ectopic expression of mutant proteins in endothelial cells revealed that expression of either mutant reduced cellular proliferation, yet regulated MAPK signalling differently, suggesting that dysregulated MAPK signalling cannot fully explain the SWS phenotype. Instead, both mutants reduced synthesis of Yes-associated protein (YAP), a transcriptional co-activator of the Hippo signalling pathway, suggesting a key role for this pathway in the vascular pathogenesis of SWS. The discovery of the GNB2 mutation sheds novel light on the pathogenesis of SWS and suggests that future research on targets of treatment should be directed towards the YAP, rather than the MAPK, signalling pathway.

Health-related quality of life in adults with drug-resistant focal epilepsy treated with modified Atkins diet in a randomized clinical trial.

Ketogenic diet, a high-fat, low-carbohydrate diet, is an established treatment for patients with severe epilepsy. We have previously reported a moderate reduction in seizure frequency after treatment with a modified Atkins diet. This study aimed to see whether dietary therapy impacts patients' health-related quality of life (HRQOL). In a randomized controlled design, we compared the change in self-reported HRQOL among adults with difficult-to-treat epilepsy after a 12-week diet intervention. Thirty-nine patients with drug-resistant focal epilepsy (age = 16-65 years) were randomized to eat a modified Atkins diet with maximum 16 g of carbohydrate per day (diet group, n = 19) or to continue eating habitual diet (control group, n = 20). No changes to the other epilepsy treatments were allowed. Patient-reported HRQOL was assessed with the Quality of Life in Epilepsy Inventory-89 (QOLIE-89). The diet group experienced a statistically significant improvement in mean total score of QOLIE-89 of 10 points compared to controls (p = .002). Moreover, although not statistically significant when using a cutoff of 50% seizure reduction, our data suggest an association between diet-induced reduction in seizure frequency and improvement in HRQOL. The improvement in HRQOL was not associated with diet-induced weight reduction.

Genome-wide decrease in DNA methylation in adults with epilepsy treated with modified ketogenic diet: A prospective study.

OBJECTIVE: The aim of this study was to investigate the impact of the modified ketogenic diet on DNA methylation in adults with epilepsy. METHODS: In this prospective study, we investigated the genome-wide DNA methylation in whole blood in 58 adults with epilepsy treated with the modified ketogenic for 12 weeks. Patients were recruited from the National Center for Epilepsy, Norway, from March 1, 2011 to February 28, 2017. DNA methylation was analyzed using the Illumina Infinium MethylationEPIC BeadChip array. Analysis of variance and paired t-test were used to identify differentially methylated loci after 4 and 12 weeks of dietary treatment. A false discovery rate approach with a significance threshold of <5% was used to adjust for multiple comparisons. RESULTS: We observed a genome-wide decrease in DNA methylation, both globally and at specific sites, after 4 and 12 weeks of dietary treatment. A substantial share of the differentially methylated positions (CpGs) were annotated to genes associated with epilepsy (n = 7), lipid metabolism (n = 8), and transcriptional regulation (n = 10). Furthermore, five of the identified genes were related to inositol phosphate metabolism, which may represent a possible mechanism by which the ketogenic diet attenuates seizures. SIGNIFICANCE: A better understanding of the modified ketogenic diet's influence at the molecular level may be the key to unraveling the mechanisms by which the diet can ameliorate seizures and possibly to identifying novel therapeutic targets for epilepsy.

Substantial early changes in bone and calcium metabolism among adult pharmacoresistant epilepsy patients on a modified Atkins diet.

OBJECTIVE: The aim of this study was to investigate whether the modified Atkins diet (MAD), a variant of the ketogenic diet, has an impact on bone- and calcium (Ca) metabolism. METHODS: Two groups of adult patients with pharmacoresistant epilepsy were investigated. One, the diet group (n = 53), was treated with MAD for 12 weeks, whereas the other, the reference group (n = 28), stayed on their habitual diet in the same period. All measurements were performed before and after the 12 weeks in both groups. We assessed bone health by measuring parathyroid hormone (PTH), Ca, 25-OH vitamin D (25-OH vit D), 1,25-OH vitamin D (1,25-OH vit D), phosphate, alkaline phosphatase (ALP), and the bone turnover markers procollagen type 1 N-terminal propeptide (P1NP) and C-terminal telopeptide collagen type 1 (CTX-1). In addition, we examined the changes of sex hormones (estradiol, testosterone, luteinizing hormone, follicle-stimulating hormone), sex hormone-binding globulin, and leptin. RESULTS: After 12 weeks of MAD, we found a significant reduction in PTH, Ca, CTX-1, P1NP, 1,25-OH vit D, and leptin. There was a significant increase in 25-OH vit D. These changes were most pronounced among patients <37 years old, and in those patients with the highest body mass index (≥25.8 kg/m²), whereas sex and type of antiseizure medication had no impact on the results. For the reference group, the changes were nonsignificant for all the analyses. In addition, the changes in sex hormones were nonsignificant. SIGNIFICANCE: Twelve weeks of MAD treatment leads to significant changes in bone and Ca metabolism, with a possible negative effect on bone health as a result. A reduced level of leptin may be a triggering mechanism. The changes could be important for patients on MAD, and especially relevant for those patients who receive treatment with MAD at an early age before peak bone mass is reached.

Effects of modified Atkins diet on thyroid function in adult patients with pharmacoresistant epilepsy.

INTRODUCTION: The use of ketogenic diet as a supplement to antiseizure medication (ASM) in refractory epilepsy has increased the past decades. This high-fat, low-carbohydrate diet mimics the metabolic state of fasting and is generally well-tolerated. However, the long-term adverse effects of the diet are unclear. The purpose of this study was to investigate whether the modified Atkins diet (MAD), a variant of the ketogenic diet, may have an impact on thyroid hormone levels. METHODS: We assessed thyroid function by measuring thyroid stimulation hormone (TSH), fT4, T3, fT3, and rT3 before diet start (baseline) and after 12 weeks on the diet in 53 adult patients with drug-resistant epilepsy. Further, we examined the correlation between the changes in thyroid function during dietary treatment and type of (i) change in seizure frequency, (ii) drugs in use, and (iii) degree of ketosis. RESULTS: After 12 weeks on the diet, we found a significant reduction in T3 and fT3 values (13.4% and 10.6%, respectively) and a significant increase in fT4 values (12.1%) compared with baseline. In addition, there was an insignificant increase in TSH and rT3. These changes were similar in women and men, and there was no correlation to drugs in use (enzyme-inducing vs. nonenzyme-inducing drugs), changes in seizure frequency, or level of ketosis. CONCLUSION: This study indicates that dietary treatment for epilepsy may bring about a modest fall in thyroid hormone levels. This could be relevant for those patients with low thyroid hormones and those treated with ASMs known to lower thyroid hormone levels. A cumulative effect of ASMs, low basal thyroid hormone levels, and ketogenic diet may therefore be of clinical importance in the case of thyroid hormones when treating patients with MAD.

The effect of infliximab in patients with chronic low back pain and Modic changes (the BackToBasic study): study protocol of a randomized, double blind, placebo-controlled, multicenter trial.

BACKGROUND: Low back pain is common and a significant number of patients experience chronic low back pain. Current treatment options offer small to moderate effects. Patients with vertebral bone marrow lesions visualized as Modic changes on magnetic resonance imaging may represent a subgroup within the low back pain population. There is evidence for inflammatory mediators being involved in development of Modic changes; hence, suppression of inflammation could be a treatment strategy for these patients. This study examines the effect of anti-inflammatory treatment with the TNF-α inhibitor infliximab in patients with chronic low back pain and Modic changes. METHODS/DESIGN: The BackToBasic trial is a multicenter, double blind, randomized controlled trial conducted at six hospitals in Norway, comparing intravenous infusions with infliximab with placebo. One hundred twenty-six patients aged 18-65 with chronic low back pain and type 1 Modic changes will be recruited from secondary care outpatients' clinics. The primary outcome is back pain-specific disability at day 154 (5 months). The study is designed to detect a difference in change of 10 (SD 18) in the Oswestry Disability Index at day 154/ 5 months. The study also aims to refine MRI-assessment, investigate safety and cost-effectiveness and explore the underlying biological mechanisms of Modic changes. DISCUSSION: Finding treatments that target underlying mechanisms could pose new treatment options for patients with low back pain. Suppression of inflammation could be a treatment strategy for patients with low back pain and Modic changes. This paper presents the design of the BackToBasic study, where we will assess the effect of an anti-inflammatory treatment versus placebo in patients with chronic low back pain and type 1 Modic changes. The study is registered at ClinicalTrials.gov under the identifier NCT03704363 . The EudraCT Number: 2017-004861-29.

Pyruvate dehydrogenase deficiency. / Pyruvatdehydrogenase-mangel.

Pyruvate dehydrogenase deficiency is a rare mitochondrial disease leading to energy deficiency in the cells. This particularly affects the central nervous system, resulting in a broad range of neurological symptoms.

Prevalence of juvenile myoclonic epilepsy in people <30 years of age-A population-based study in Norway.

OBJECTIVE: Despite juvenile myoclonic epilepsy (JME) being considered one of the most common epilepsies, population-based prevalence studies of JME are lacking. Our aim was to estimate the prevalence of JME in a Norwegian county, using updated diagnostic criteria. METHODS: This was a cross-sectional study, based on reviews of the medical records of all patients with a diagnosis of epilepsy at Drammen Hospital in the period 1999-2013. The study population consisted of 98,152 people <30 years of age. Subjects diagnosed with JME, unspecified genetic generalized epilepsy, or absence epilepsy were identified. All of these patients were contacted and asked specifically about myoclonic jerks. Electroencephalography (EEG) recordings and medical records were reevaluated for those who confirmed myoclonic jerks. Information about seizure onset was obtained from the medical records, and annual frequency of new cases was estimated. RESULTS: A total of 55 subjects fulfilled the diagnostic criteria for JME. The point prevalence was estimated at 5.6/10,000. JME constituted 9.3% of all epilepsies in the age group we investigated. Of subjects diagnosed with either unspecified genetic generalized epilepsy or absence epilepsy, 21% and 12%, respectively, had JME. We identified 21 subjects with JME (38%) who had not been diagnosed previously. Six subjects (11%) had childhood absence epilepsy evolving into JME. Between 2009 and 2013, the average frequency of JME per 100,000 people of all ages per year was estimated at 1.7. SIGNIFICANCE: A substantial portion of people with JME seem to go undiagnosed, as was the case for more than one third of the subjects in this study. By investigating subjects diagnosed with unspecified genetic generalized epilepsy or absence epilepsy, we found a prevalence of JME that was considerably higher than previously reported. We conclude that JME may go undiagnosed due to the underrecognition of myoclonic jerks. To make a correct diagnosis, clinicians need to ask specifically about myoclonic jerks.

Pathogenic variants in KCTD7 perturb neuronal K+ fluxes and glutamine transport.

Progressive myoclonus epilepsy is a heterogeneous group of disorders characterized by myoclonic and tonic-clonic seizures, ataxia and cognitive decline. We here present two affected brothers. At 9 months of age the elder brother developed ataxia and myoclonic jerks. In his second year he lost the ability to walk and talk, and he developed drug-resistant progressive myoclonus epilepsy. The cerebrospinal fluid level of glutamate was decreased while glutamine was increased. His younger brother manifested similar symptoms from 6 months of age. By exome sequencing of the proband we identified a novel homozygous frameshift variant in the potassium channel tetramerization domain 7 (KCTD7) gene (NM_153033.1:c.696delT: p.F232fs), which results in a truncated protein. The identified F232fs variant is inherited in an autosomal recessive manner, and the healthy consanguineous parents carry the variant in a heterozygous state. Bioinformatic analyses and structure modelling showed that KCTD7 is a highly conserved protein, structurally similar to KCTD5 and several voltage-gated potassium channels, and that it may form homo- or heteromultimers. By heterologous expression in Xenopus laevis oocytes, we demonstrate that wild-type KCTD7 hyperpolarizes cells in a K+ dependent manner and regulates activity of the neuronal glutamine transporter SAT2 (Slc38a2), while the F232fs variant impairs K+ fluxes and obliterates SAT2-dependent glutamine transport. Characterization of four additional disease-causing variants (R94W, R184C, N273I, Y276C) bolster these results and reveal the molecular mechanisms involved in the pathophysiology of KCTD7-related progressive myoclonus epilepsy. Thus, our data demonstrate that KCTD7 has an impact on K+ fluxes, neurotransmitter synthesis and neuronal function, and that malfunction of the encoded protein may lead to progressive myoclonus epilepsy.

GLUT1-deficiency syndrome: Report of a four-generation Norwegian family with a mild phenotype.

INTRODUCTION: Glucose transporter type 1 deficiency syndrome (GLUT1-DS) is a rare metabolic encephalopathy with a wide variation of clinical phenotypes. Familial variants are often milder than de novo cases, and may therefore remain undiagnosed. The aim of this study was to characterize the clinical course of GLUT1-DS in a four-generation Norwegian family where the oldest generations had never received any treatment. METHOD: Through interviews and clinical investigations, we characterized a family of 26 members, where 11 members had symptoms strongly suggesting GLUT1-DS. All members were offered genetic testing of the SLC2A1 gene. Affected members were offered treatment with ketogenic diet, and the effect of the treatment was registered. RESULTS: We sequenced the SLC2A1 gene in 13 members, and found that 10, all with symptoms, had the c.823G>A (p.Ala275Thr) variant. All affected members had experienced early-onset epilepsy, paroxysmal exercise-induced dyskinesias, and most had mild learning disability. Moreover, some had symptoms and signs of a distal neuropathy in addition to reduced sense of orientation and excessive daytime sleep. Their load of symptoms had decreased over the years, although that they never had received any treatment. Nevertheless, those who started dietary treatment all experienced an improved quality of life. CONCLUSION: We report a four-generation family with GLUT1-DS where the disease has a mild course, even when untreated. In addition to classical GLUT1-DS features, we also describe symptoms which have never been reported in GLUT1-DS previously. As such, this family extends the phenotypic spectrum of GLUT1-DS and underlines the importance of diagnosing also relatively mildly affected patients, even in adult life, as they also seem to benefit from dietary treatment.

Strømme Syndrome Is a Ciliary Disorder Caused by Mutations in CENPF.

Strømme syndrome was first described by Strømme et al. (1993) in siblings presenting with "apple peel" type intestinal atresia, ocular anomalies and microcephaly. The etiology remains unknown to date. We describe the long-term clinical follow-up data for the original pair of siblings as well as two previously unreported siblings with a severe phenotype overlapping that of the Strømme syndrome including fetal autopsy results. Using family-based whole-exome sequencing, we identified truncating mutations in the centrosome gene CENPF in the two nonconsanguineous Caucasian sibling pairs. Compound heterozygous inheritance was confirmed in both families. Recently, mutations in this gene were shown to cause a fetal lethal phenotype, the phenotype and functional data being compatible with a human ciliopathy [Waters et al., 2015]. We show for the first time that Strømme syndrome is an autosomal-recessive disease caused by mutations in CENPF that can result in a wide phenotypic spectrum.

Does ketogenic diet improve cognitive function in patients with GLUT1-DS? A 6- to 17-month follow-up study.

The aim of this study was to investigate the effects of ketogenic diet (KD) on cognitive function in patients with glucose transporter protein 1 deficiency syndrome (GLUT1-DS). Six patients with GLUT1-DS who were referred to the National Centre for Epilepsy in Norway during the period of November 2011-September 2013 were included. They were diagnosed with GLUT1-DS on the basis of early-onset seizures and developmental delay (with or without movement disorders or microcephaly) in addition to CSF-to-blood glucose ratio below 0.5. They were all treated with either classical KD or modified Atkins diet (MAD). The effect of the diet with >90% reduction in the seizure frequency was, in retrospect, considered as a support for the diagnosis. The patients underwent standardized neuropsychological assessment before the diet was initiated, and they were reassessed after a minimum of six months on the diet. The neuropsychological tests were individually selected for each patient in order to match their cognitive level. The main finding was a considerable improvement in several aspects of neuropsychological functioning after 6-17 months of dietary treatment in all the six patients. The greatest progress was seen in the youngest children. Our findings suggest that early diagnosis and dietary treatment are important in order to prevent developmental delay. However, also adults with GLUT1-DS may profit from dietary treatment by improving alertness, setting the stage for enhanced learning capacity, as well as physical endurance and quality of life.

CHD2 mutations in Lennox-Gastaut syndrome.

Lennox-Gastaut syndrome (LGS) is an epileptic encephalopathy with a heterogeneous etiology. In this study, we aimed to explore the role of CHD2 in LGS, as CHD2 mutations have been described recently in various epileptic encephalopathies. We have previously identified one patient with a large deletion affecting the CHD2 gene in a group of 22 patients with LGS or LGS-like epilepsy. In the remaining 17 patients without known etiology, Sanger sequencing revealed a de novo 1-bp duplication in the CHD2 gene in another patient. This mutation leads to a frameshift and, consequently, a premature stop codon 49bp downstream of the mutation. The patient had prominent myoclonic seizures and photosensitivity, thus, sharing phenotypic features with previously reported patients with CHD2-related epilepsy. In our original material of 22 patients with LGS features, we have now found two (9%) with mutations in the CHD2 gene. Our findings suggest that CHD2 mutations are important in the etiological spectrum of LGS.

Occurrence of GLUT1 deficiency syndrome in patients treated with ketogenic diet.

Glucose transporter 1 deficiency syndrome (GLUT1-DS) is a treatable metabolic encephalopathy caused by a mutation in the SLC2A1 gene. This mutation causes a compromised transport of glucose across the blood-brain barrier. The treatment of choice is ketogenic diet, with which most patients become seizure-free. At the National Centre for Epilepsy, we have, since 2005, offered treatment with ketogenic diet (KD) and modified Atkins diet (MAD) to children with difficult-to-treat epilepsy. As we believe many children with GLUT1-DS are unrecognized, the aim of this study was to search for patients with GLUT1-DS among those who had been responders (>50% reduction in seizure frequency) to KD or MAD. Of the 130 children included, 58 (44%) were defined as responders. Among these, 11 were already diagnosed with GLUT1-DS. No mutations in the SLC2A1 gene were detected in the remaining patients. However, the clinical features of these patients differed considerably from the patients diagnosed with GLUT1-DS. While 9 out of 10 patients with GLUT1-DS became seizure-free with dietary treatment, only 3 out of the 33 remaining patients were seizure-free with KD or MAD treatment. We therefore conclude that a seizure reduction of >50% following dietary treatment is not a suitable criterion for identifying patients with GLUT1-DS, as these patients generally achieve complete seizure freedom shortly after diet initiation.

Psychiatric comorbidity in relation to clinical characteristics of epilepsy: A retrospective observational study.

PURPOSE: Prevalence of psychiatric disorders in people with epilepsy is high. However, diagnostic validity and information about the nature of the seizure disorders are often poor in population-based studies. In a well validated and classified patient sample, we investigated psychiatric comorbidity according to clinical characteristics. METHOD: Participants in The Trøndelag Health Study (HUNT) with ≥ 2 diagnostic epilepsy codes during 1987-2019 were identified. Medical records were reviewed, and epilepsy was validated and classified according to ILAE. Psychiatric comorbidity was defined by ICD-codes. RESULTS: In 448 individuals with epilepsy, 35% had at least one psychiatric disorder (anxiety and related disorders 23%, mood disorders 15%, substance abuse and personality disorders 7%, and psychosis 3%). Comorbidity was significantly higher in women than in men (p = 0.007). The prevalence of psychiatric disorders was 37% in both focal and generalized epilepsy. In focal epilepsy, it was significantly lower when etiology was structural (p = 0.011), whereas it was higher when the cause was unknown (p = 0.024). Comorbidity prevalence was 35% both in patients achieving seizure freedom and in those with active epilepsy but 38% among 73 patients with epilepsy resolved. CONCLUSION: Just over one third of people with epilepsy had psychiatric comorbidities. The prevalence was equal in focal and generalized epilepsy but was significantly higher in focal epilepsy of unknown cause compared to lesional epilepsy. Comorbidity was independent of seizure control at last follow-up but was slightly more common in those with resolved epilepsy, often having non-acquired genetic etiologies possibly linked to neuropsychiatric susceptibility.

Decreased serum concentrations of antiseizure medications in children with drug resistant epilepsy following treatment with ketogenic diet.

OBJECTIVE: To examine the potential influence of a ketogenic diet on serum concentrations of antiseizure medications (ASMs) in children with drug resistant epilepsy. METHODS: We investigated the serum concentrations of ASMs in 25 children with drug resistant epilepsy, 2-13 years of age, treated with a classical ketogenic diet for 12 weeks. The patients were recruited from the National Centre for Epilepsy from August 15th, 2017, to January 24th, 2022. Changes in ASM serum concentrations were analyzed using a mixed effect model analysis. Significance level was set at P < 0.05 for all comparisons. RESULTS: The participants used 12 different ASMs during the study. The mean number of ASMs was 2.4 (±SD 0.7). None of the participants changed the type or dose of the ASMs during the intervention period. The serum concentrations of clobazam (n = 9, P = 0.002), desmethylclobazam (n = 9, P = 0.010), and lamotrigine (n = 6, P = 0.016) decreased significantly during the dietary treatment. The analytes with the largest reduction in serum concentration after 12 weeks of dietary treatment were clobazam (mean change -38%) and desmethylclobazam (mean change -37%). We found no significant change in the serum concentrations of levetiracetam, topiramate, and valproic acid. SIGNIFICANCE: We identified a significant decrease in the serum concentrations of clobazam, desmethylclobazam, and lamotrigine following a 12-week ketogenic diet intervention in children with drug resistant epilepsy. An unintended decrease in the serum concentrations of ASMs may render the patient prone to seizures. Measurements of ASM serum concentrations might be useful in patients on a ketogenic diet, especially in patients with lack of efficacy of the dietary treatment.

Cytokine Patterns as Predictors of Antibiotic Treatment Effect in Chronic Low Back Pain with Modic Changes: Subgroup Analyses of a Randomized Trial (AIM Study).

Objective: Randomized trials testing the effect of antibiotics for chronic low back pain (LBP) with vertebral bone marrow changes on MRI (Modic changes) report inconsistent results. A proposed explanation is subgroups with low grade discitis where antibiotics are effective, but there is currently no method to identify such subgroups. The objective of the present study was to evaluate whether distinct patterns of serum cytokine levels predict any treatment effect of oral amoxicillin at one-year follow-up in patients with chronic low back pain and Modic changes at the level of a previous lumbar disc herniation. Design: We used data from an overpowered, randomized, placebo-controlled trial (the AIM study) that tested 100 days of oral 750 mg amoxicillin vs placebo three times daily in hospital outpatients with chronic (>6 months) LBP with pain intensity ≥5 on a 0-10 numerical rating scale and Modic changes type 1 (oedema type) or 2 (fatty type). We measured serum levels of 40 inflammatory cytokines at baseline and analysed six predefined potential predictors of treatment effect based on cytokine patterns in 78 randomized patients; three analyses with recursive partitioning, one based on cluster analysis and two based on principal component analyses. The primary outcome was the Roland-Morris Disability Questionnaire score at one-year follow-up in the intention to treat population. The methodology and overall results of the AIM study were published previously. Results: The 78 patients were 25-62 years old and 47 (60%) were women. None of the three recursive partitioning analyses resulted in any suggested subgroups. Of all main analyses, the largest effect estimate (mean difference between antibiotic and placebo groups) was seen in a subgroup not predefined as of main interest (Cluster category 3+4; -2.0, 95% CI: -5.2-1.3, RMDQ points; p-value for interaction 0.54). Conclusion: Patterns of inflammatory serum cytokine levels did not predict treatment effect of amoxicillin in patients with chronic LBP and Modic changes. Clinical Trial Registration Number: ClinicalTrials.gov (identifier: NCT02323412).

[Juvenile myoclonic epilepsy]. / Juvenil myoklonusepilepsi.

BACKGROUND: Juvenile myoclonic epilepsy (JME) is a generalised epilepsy with seizure onset in youth. The aim of this review is to present updated knowledge about the etiology, diagnosis and treatment of JME. MATERIAL AND METHOD: The review is based on a judicious selection of original English language articles, meta-analyses, and reviews found in PubMed, and the authors' own experience with the patient group. RESULTS: Seizure onset occurs in adolescence. All have myoclonias, about 90 % have generalized tonic-clonic seizures, and one third have absences. Myoclonic jerks are frequently the debut symptom, while tonic-clonic seizures appear later on. Patients are particularly susceptible to seizures shortly after waking. It is important to ask specifically about myoclonias as most patients do not report jerks spontaneously. The electroencephalograms of 44-81 % of the patients show discharges of 4-6 Hz polyspike waves. Focal EEG abnormalities may be seen in about 30 %. When patients are treated with valproate and seizure-precipitating factors are avoided, especially sleep deprivation, about 80 % become seizure-free. Lamotrigine and levetiracetam are alternative therapies for women of childbearing age. Attempts to taper off the medication after several years of seizure freedom entail a high risk of seizure relapse. INTERPRETATION: As there may be features of focal epilepsy in the seizure semiology and/or the EEGs, it may be difficult to diagnose JME. Thus, many patients are misdiagnosed as having a focal epilepsy and are given antiepileptic drugs that may aggravate the tendency to seizures.

[Dravet syndrome as a cause of epilepsy and learning disability]. / Dravets syndrom som årsak til epilepsi og utviklingshemning.

BACKGROUND: Dravet syndrome is a severe, genetic epileptic encephalopathy with seizures starting during the first year of life. We present a review of the genetic and clinical picture along with treatment aspects. MATERIAL AND METHODS: This review is based on a non-systematic literature search in PubMed until April 2011 and the personal experiences of the authors. RESULTS: Dravet syndrome should be suspected in children with febrile hemiconvulsions or tonic-clonic seizures in the first year of life. Non-febrile seizures also occur, and other seizure types gradually appear, e.g. myoclonic jerks, atypical absences or focal seizures. In adulthood the clinical picture is less characteristic. The clinical diagnosis is supported by genetic testing; 70-80% of the patients have mutations in the sodium channel subunit gene SCN1A. Seizure control is difficult to achieve, but valproate, benzodiazepines and stiripentol may cause improvement, whereas sodium channel blockers, such as lamotrigine and carbamazepine may aggravate the tendency towards seizures. INTERPRETATION: Dravet syndrome appears to be an under-recognised condition among both children and adults with severe epilepsy and learning disability. Clinical information from the first years of life is essential in making the diagnosis. A correct diagnosis at an early age is essential for appropriate treatment and genetic counselling.