RESUMO
Convulsive status epilepticus (CSE) is the most common neurological emergency in children and the second most common neurological emergency in adults. Mortality is low, but morbidity, including neuro-disability, learning difficulties, and a de-novo epilepsy, may be as high as 22%. The longer the duration of CSE, the more difficult it is to terminate, and the greater the risk of morbidity. Convulsive status epilepticus is usually managed using specific national or local algorithms. The first-line treatment is administered when a tonic-clonic or focal motor clonic seizure has lasted five minutes (impending or premonitory CSE). Second-line treatment is administered when the CSE has persisted after two doses of a first-line treatment (established CSE). Randomised clinical trial (RCT) evidence supports the use of benzodiazepines as a first-line treatment of which the most common are buccal or intra-nasal midazolam, rectal diazepam and intravenous lorazepam. Alternative drugs, for which there are considerably less RCT data, are intra-muscular midazolam and intravenous clonazepam. Up until 2019, phenobarbital and phenytoin (or fosphenytoin) were the preferred second-line treatments but with no good supporting RCT evidence. Robust RCT data are now available which has provided important information on second-line treatments, specifically phenytoin (or fosphenytoin), levetiracetam and sodium valproate. Lacosamide is an alternative second-line treatment but with no supporting RCT evidence. Current evidence indicates that first, buccal or intranasal midazolam or intravenous lorazepam are the most effective and the most patient and carer-friendly first-line anti-seizure medications to treat impending or premonitory CSE and second, that there is no difference in efficacy between levetiracetam, phenytoin (or fosphenytoin) or sodium valproate for the treatment of established CSE. Pragmatically, levetiracetam or sodium valproate are preferred to phenytoin (or fosphenytoin) because of their ease of administration and lack of serious adverse side-effects, including potentially fatal cardiac arrhythmias. Sodium valproate must be used with caution in children aged three and under because of the rare risk of hepatotoxicity and particularly if there is an underlying mitochondrial disorder.
RESUMO
BACKGROUND: Levetiracetam (Keppra®, UCB Pharma Ltd, Slough, UK) and zonisamide (Zonegran®, Eisai Co. Ltd, Tokyo, Japan) are licensed as monotherapy for focal epilepsy, and levetiracetam is increasingly used as a first-line treatment for generalised epilepsy, particularly for women of childbearing age. However, there is uncertainty as to whether or not they should be recommended as first-line treatments owing to a lack of evidence of clinical effectiveness and cost-effectiveness. OBJECTIVES: To compare the clinical effectiveness and cost-effectiveness of lamotrigine (Lamictal®, GlaxoSmithKline plc, Brentford, UK) (standard treatment) with levetiracetam and zonisamide (new treatments) for focal epilepsy, and to compare valproate (Epilim®, Sanofi SA, Paris, France) (standard treatment) with levetiracetam (new treatment) for generalised and unclassified epilepsy. DESIGN: Two pragmatic randomised unblinded non-inferiority trials run in parallel. SETTING: Outpatient services in NHS hospitals throughout the UK. PARTICIPANTS: Those aged ≥ 5 years with two or more spontaneous seizures that require anti-seizure medication. INTERVENTIONS: Participants with focal epilepsy were randomised to receive lamotrigine, levetiracetam or zonisamide. Participants with generalised or unclassifiable epilepsy were randomised to receive valproate or levetiracetam. The randomisation method was minimisation using a web-based program. MAIN OUTCOME MEASURES: The primary outcome was time to 12-month remission from seizures. For this outcome, and all other time-to-event outcomes, we report hazard ratios for the standard treatment compared with the new treatment. For the focal epilepsy trial, the non-inferiority limit (lamotrigine vs. new treatments) was 1.329. For the generalised and unclassified epilepsy trial, the non-inferiority limit (valproate vs. new treatments) was 1.314. Secondary outcomes included time to treatment failure, time to first seizure, time to 24-month remission, adverse reactions, quality of life and cost-effectiveness. RESULTS: Focal epilepsy. A total of 990 participants were recruited, of whom 330 were randomised to receive lamotrigine, 332 were randomised to receive levetiracetam and 328 were randomised to receive zonisamide. Levetiracetam did not meet the criteria for non-inferiority (hazard ratio 1.329) in the primary intention-to-treat analysis of time to 12-month remission (hazard ratio vs. lamotrigine 1.18, 97.5% confidence interval 0.95 to 1.47), but zonisamide did meet the criteria (hazard ratio vs. lamotrigine 1.03, 97.5% confidence interval 0.83 to 1.28). In the per-protocol analysis, lamotrigine was superior to both levetiracetam (hazard ratio 1.32, 95% confidence interval 1.05 to 1.66) and zonisamide (hazard ratio 1.37, 95% confidence interval 1.08 to 1.73). For time to treatment failure, lamotrigine was superior to levetiracetam (hazard ratio 0.60, 95% confidence interval 0.46 to 0.77) and zonisamide (hazard ratio 0.46, 95% confidence interval 0.36 to 0.60). Adverse reactions were reported by 33% of participants starting lamotrigine, 44% starting levetiracetam and 45% starting zonisamide. In the economic analysis, both levetiracetam and zonisamide were more costly and less effective than lamotrigine and were therefore dominated. Generalised and unclassifiable epilepsy. Of 520 patients recruited, 260 were randomised to receive valproate and 260 were randomised to receive to levetiracetam. A total of 397 patients had generalised epilepsy and 123 had unclassified epilepsy. Levetiracetam did not meet the criteria for non-inferiority in the primary intention-to-treat analysis of time to 12-month remission (hazard ratio 1.19, 95% confidence interval 0.96 to 1.47; non-inferiority margin 1.314). In the per-protocol analysis of time to 12-month remission, valproate was superior to levetiracetam (hazard ratio 1.68, 95% confidence interval 1.30 to 2.15). Valproate was superior to levetiracetam for time to treatment failure (hazard ratio 0.65, 95% confidence interval 0.50 to 0.83). Adverse reactions were reported by 37.4% of participants receiving valproate and 41.5% of those receiving levetiracetam. Levetiracetam was both more costly (incremental cost of £104, 95% central range -£587 to £1234) and less effective (incremental quality-adjusted life-year of -0.035, 95% central range -0.137 to 0.032) than valproate, and was therefore dominated. At a cost-effectiveness threshold of £20,000 per quality-adjusted life-year, levetiracetam was associated with a probability of 0.17 of being cost-effective. LIMITATIONS: The SANAD II trial was unblinded, which could have biased results by influencing decisions about dosing, treatment failure and the attribution of adverse reactions. FUTURE WORK: SANAD II data could now be included in an individual participant meta-analysis of similar trials, and future similar trials are required to assess the clinical effectiveness and cost-effectiveness of other new treatments, including lacosamide and perampanel. CONCLUSIONS: Focal epilepsy - The SANAD II findings do not support the use of levetiracetam or zonisamide as first-line treatments in focal epilepsy. Generalised and unclassifiable epilepsy - The SANAD II findings do not support the use of levetiracetam as a first-line treatment for newly diagnosed generalised epilepsy. For women of childbearing potential, these results inform discussions about the benefit (lower teratogenicity) and harm (worse seizure outcomes and higher treatment failure rate) of levetiracetam compared with valproate. TRIAL REGISTRATION: Current Controlled Trials ISRCTN30294119 and EudraCT 2012-001884-64. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 75. See the NIHR Journals Library website for further project information.
BACKGROUND AND METHODS: The SANAD II trial was a clinical trial designed to identify the most clinically effective and cost-effective treatment for adults and children aged > 5 years with newly diagnosed epilepsy. There are two main epilepsy types: focal and generalised. In focal epilepsy, seizures start at a single place in the brain (a focus), whereas in generalised epilepsy seizures start in both sides of the brain at the same time. Anti-seizure medications are the main treatment. For people with newly diagnosed epilepsy, the first anti-seizure medication should control the seizures as quickly as possible while avoiding side effects. The first-choice treatments are lamotrigine (Lamictal®, GlaxoSmithKline plc, Brentford, UK) for focal epilepsy and valproate (Epilim®, Sanofi SA, Paris, France) for generalised epilepsy (however, the latter should be avoided in women who could become pregnant). A number of newer anti-seizure medications have been approved for NHS use, but it is unclear whether or not they should be used as first-line treatments. The SANAD II trial focused on the new medicines levetiracetam (Keppra®, UCB Pharma Ltd, Slough, UK) and zonisamide (Zonegran®, Eisai Co. Ltd, Tokyo, Japan). We recruited 1510 people aged ≥ 5 years with newly diagnosed epilepsy: 990 with focal epilepsy and 520 with generalised or unclassified epilepsy. FINDINGS: FOCAL EPILEPSY: People starting treatment with levetiracetam or zonisamide were significantly less likely to have a 12-month remission from seizures than people starting treatment with lamotrigine, unless they were changed to another anti-seizure medication. Side effects that were thought to be caused by anti-seizure medications were reported by 33% of participants starting lamotrigine, 44% of those starting levetiracetam and 45% of those starting zonisamide. The cost-effectiveness analyses showed that neither levetiracetam nor zonisamide is value for money for the NHS when compared with lamotrigine. The SANAD II findings do not support the use of levetiracetam or zonisamide as first-line treatments in focal epilepsy. FINDINGS: GENERALISED AND UNCLASSIFIABLE EPILEPSY: People starting treatment with levetiracetam were significantly less likely to have a 12-month remission from seizures than people starting valproate, unless they were changed to another anti-seizure medication. Side effects that were thought to be caused by anti-seizure medications were reported by 37% of participants starting valproate and 42% of participants starting levetiracetam. The cost-effectiveness analyses showed that levetiracetam is not good value for money for the NHS when compared with valproate. The SANAD II findings do not support the use of levetiracetam as a first-line treatment for newly diagnosed generalised epilepsy. Importantly, our results will inform treatment decisions for women, who may choose a less effective treatment that is safer in pregnancy.
Assuntos
Epilepsias Parciais , Epilepsia , Pré-Escolar , Análise Custo-Benefício , Epilepsias Parciais/tratamento farmacológico , Epilepsia/tratamento farmacológico , Feminino , Humanos , Lamotrigina/uso terapêutico , Levetiracetam/uso terapêutico , Qualidade de Vida , Ácido Valproico/uso terapêutico , Zonisamida/uso terapêuticoRESUMO
BACKGROUND: Levetiracetam and zonisamide are licensed as monotherapy for patients with focal epilepsy, but there is uncertainty as to whether they should be recommended as first-line treatments because of insufficient evidence of clinical effectiveness and cost-effectiveness. We aimed to assess the long-term clinical effectiveness and cost-effectiveness of levetiracetam and zonisamide compared with lamotrigine in people with newly diagnosed focal epilepsy. METHODS: This randomised, open-label, controlled trial compared levetiracetam and zonisamide with lamotrigine as first-line treatment for patients with newly diagnosed focal epilepsy. Adult and paediatric neurology services across the UK recruited participants aged 5 years or older (with no upper age limit) with two or more unprovoked focal seizures. Participants were randomly allocated (1:1:1) using a minimisation programme with a random element utilising factor to receive lamotrigine, levetiracetam, or zonisamide. Participants and investigators were not masked and were aware of treatment allocation. SANAD II was designed to assess non-inferiority of both levetiracetam and zonisamide to lamotrigine for the primary outcome of time to 12-month remission. Anti-seizure medications were taken orally and for participants aged 12 years or older the initial advised maintenance doses were lamotrigine 50 mg (morning) and 100 mg (evening), levetiracetam 500 mg twice per day, and zonisamide 100 mg twice per day. For children aged between 5 and 12 years the initial daily maintenance doses advised were lamotrigine 1·5 mg/kg twice per day, levetiracetam 20 mg/kg twice per day, and zonisamide 2·5 mg/kg twice per day. All participants were included in the intention-to-treat (ITT) analysis. The per-protocol (PP) analysis excluded participants with major protocol deviations and those who were subsequently diagnosed as not having epilepsy. Safety analysis included all participants who received one dose of any study drug. The non-inferiority limit was a hazard ratio (HR) of 1·329, which equates to an absolute difference of 10%. A HR greater than 1 indicated that an event was more likely on lamotrigine. The trial is registered with the ISRCTN registry, 30294119 (EudraCt number: 2012-001884-64). FINDINGS: 990 participants were recruited between May 2, 2013, and June 20, 2017, and followed up for a further 2 years. Patients were randomly assigned to receive lamotrigine (n=330), levetiracetam (n=332), or zonisamide (n=328). The ITT analysis included all participants and the PP analysis included 324 participants randomly assigned to lamotrigine, 320 participants randomly assigned to levetiracetam, and 315 participants randomly assigned to zonisamide. Levetiracetam did not meet the criteria for non-inferiority in the ITT analysis of time to 12-month remission versus lamotrigine (HR 1·18; 97·5% CI 0·95-1·47) but zonisamide did meet the criteria for non-inferiority in the ITT analysis versus lamotrigine (1·03; 0·83-1·28). The PP analysis showed that 12-month remission was superior with lamotrigine than both levetiracetam (HR 1·32 [97·5% CI 1·05 to 1·66]) and zonisamide (HR 1·37 [1·08-1·73]). There were 37 deaths during the trial. Adverse reactions were reported by 108 (33%) participants who started lamotrigine, 144 (44%) participants who started levetiracetam, and 146 (45%) participants who started zonisamide. Lamotrigine was superior in the cost-utility analysis, with a higher net health benefit of 1·403 QALYs (97·5% central range 1·319-1·458) compared with 1·222 (1·110-1·283) for levetiracetam and 1·232 (1·112, 1·307) for zonisamide at a cost-effectiveness threshold of £20â000 per QALY. Cost-effectiveness was based on differences between treatment groups in costs and QALYs. INTERPRETATION: These findings do not support the use of levetiracetam or zonisamide as first-line treatments for patients with focal epilepsy. Lamotrigine should remain a first-line treatment for patients with focal epilepsy and should be the standard treatment in future trials. FUNDING: National Institute for Health Research Health Technology Assessment programme.
Assuntos
Anticonvulsivantes/efeitos adversos , Análise Custo-Benefício , Epilepsias Parciais/tratamento farmacológico , Lamotrigina/uso terapêutico , Levetiracetam/uso terapêutico , Resultado do Tratamento , Zonisamida/uso terapêutico , Administração Oral , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
BACKGROUND: Valproate is a first-line treatment for patients with newly diagnosed idiopathic generalised or difficult to classify epilepsy, but not for women of child-bearing potential because of teratogenicity. Levetiracetam is increasingly prescribed for these patient populations despite scarcity of evidence of clinical effectiveness or cost-effectiveness. We aimed to compare the long-term clinical effectiveness and cost-effectiveness of levetiracetam compared with valproate in participants with newly diagnosed generalised or unclassifiable epilepsy. METHODS: We did an open-label, randomised controlled trial to compare levetiracetam with valproate as first-line treatment for patients with generalised or unclassified epilepsy. Adult and paediatric neurology services (69 centres overall) across the UK recruited participants aged 5 years or older (with no upper age limit) with two or more unprovoked generalised or unclassifiable seizures. Participants were randomly allocated (1:1) to receive either levetiracetam or valproate, using a minimisation programme with a random element utilising factors. Participants and investigators were aware of treatment allocation. For participants aged 12 years or older, the initial advised maintenance doses were 500 mg twice per day for levetiracetam and valproate, and for children aged 5-12 years, the initial daily maintenance doses advised were 25 mg/kg for valproate and 40 mg/kg for levetiracetam. All drugs were administered orally. SANAD II was designed to assess the non-inferiority of levetiracetam compared with valproate for the primary outcome time to 12-month remission. The non-inferiority limit was a hazard ratio (HR) of 1·314, which equates to an absolute difference of 10%. A HR greater than 1 indicated that an event was more likely on valproate. All participants were included in the intention-to-treat (ITT) analysis. Per-protocol (PP) analyses excluded participants with major protocol deviations and those who were subsequently diagnosed as not having epilepsy. Safety analyses included all participants who received one dose of any study drug. This trial is registered with the ISRCTN registry, 30294119 (EudraCt number: 2012-001884-64). FINDINGS: 520 participants were recruited between April 30, 2013, and Aug 2, 2016, and followed up for a further 2 years. 260 participants were randomly allocated to receive levetiracetam and 260 participants to receive valproate. The ITT analysis included all participants and the PP analysis included 255 participants randomly allocated to valproate and 254 randomly allocated to levetiracetam. Median age of participants was 13·9 years (range 5·0-94·4), 65% were male and 35% were female, 397 participants had generalised epilepsy, and 123 unclassified epilepsy. Levetiracetam did not meet the criteria for non-inferiority in the ITT analysis of time to 12-month remission (HR 1·19 [95% CI 0·96-1·47]); non-inferiority margin 1·314. The PP analysis showed that the 12-month remission was superior with valproate than with levetiracetam. There were two deaths, one in each group, that were unrelated to trial treatments. Adverse reactions were reported by 96 (37%) participants randomly assigned to valproate and 107 (42%) participants randomly assigned to levetiracetam. Levetiracetam was dominated by valproate in the cost-utility analysis, with a negative incremental net health benefit of -0·040 (95% central range -0·175 to 0·037) and a probability of 0·17 of being cost-effectiveness at a threshold of £20â000 per quality-adjusted life-year. Cost-effectiveness was based on differences between treatment groups in costs and quality-adjusted life-years. INTERPRETATION: Compared with valproate, levetiracetam was found to be neither clinically effective nor cost-effective. For girls and women of child-bearing potential, these results inform discussions about benefit and harm of avoiding valproate. FUNDING: National Institute for Health Research Health Technology Assessment Programme.
Assuntos
Epilepsia Generalizada/tratamento farmacológico , Levetiracetam/economia , Levetiracetam/uso terapêutico , Ácido Valproico/economia , Ácido Valproico/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticonvulsivantes/economia , Anticonvulsivantes/uso terapêutico , Criança , Pré-Escolar , Análise Custo-Benefício , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
BACKGROUND: Alternatives to prospective informed consent enable the conduct of paediatric emergency and critical care trials. Research without prior consent (RWPC) involves practitioners approaching parents after an intervention has been given and seeking consent for their child to continue in the trial. As part of an embedded study in the 'Emergency treatment with Levetiracetam or Phenytoin in Status Epilepticus in children' (EcLiPSE) trial, we explored how practitioners described the trial and RWPC during recruitment discussions, and how well this information was understood by parents. We aimed to develop a framework to assist trial conversations in future paediatric emergency and critical care trials using RWPC. METHODS: Qualitative methods embedded within the EcLiPSE trial processes, including audiorecorded practitioner-parent trial discussions and telephone interviews with parents. We analysed data using thematic analysis, drawing on the Realpe et al (2016) model for recruitment to trials. RESULTS: We analysed 76 recorded trial discussions and conducted 30 parent telephone interviews. For 19 parents, we had recorded trial discussion and interview data, which were matched for analysis. Parental understanding of the EcLiPSE trial was enhanced when practitioners: provided a comprehensive description of trial aims; explained the reasons for RWPC; discussed uncertainty about which intervention was best; provided a balanced description of trial intervention; provided a clear explanation about randomisation and provided an opportunity for questions. We present a seven-step framework to assist recruitment practice in trials involving RWPC. CONCLUSION: This study provides a framework to enhance recruitment practice and parental understanding in paediatric emergency and critical care trials involving RWPC. Further testing of this framework is required.
Assuntos
Cuidados Críticos , Serviço Hospitalar de Emergência , Levetiracetam/uso terapêutico , Pais/psicologia , Fenitoína/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Estado Epiléptico/tratamento farmacológico , Anticonvulsivantes/uso terapêutico , Criança , Coleta de Dados/métodos , Inglaterra , Feminino , Humanos , Consentimento Livre e Esclarecido , Masculino , Estudos Multicêntricos como Assunto , Ensaios Clínicos Pragmáticos como Assunto , Pesquisa QualitativaRESUMO
BACKGROUND: Key challenges to the successful conduct of The Emergency treatment with Levetiracetam or Phenytoin in Status Epilepticus in children (EcLiPSE) trial were identified at the pre-trial stage. These included practitioner anxieties about conducting research without prior consent (RWPC), inexperience in conducting an ED-led trial and use of a medication that was not usual ED practice. As part of an embedded study, we explored parent and practitioner experiences of recruitment, RWPC and conduct of the trial to inform the design and conduct of future ED-led trials. METHODS: A mixed-methods study within a trial involving (1) questionnaires and interviews with parents of randomised children, (2) interviews and focus groups with EcLiPSE practitioners and (3) audio-recorded trial discussions. We analysed data using thematic analysis and descriptive statistics as appropriate. RESULTS: A total of 143 parents (93 mothers, 39 fathers, 11 missing information) of randomised children completed a questionnaire and 30 (25 mothers, 5 fathers) were interviewed. We analysed 76 recorded trial recruitment discussions. Ten practitioners (4 medical, 6 nursing) were interviewed, 36 (16 medical, 20 nursing) participated in one of six focus groups. Challenges to the success of the trial were addressed by having a clinically relevant research question, pragmatic trial design, parent and practitioner support for EcLiPSE recruitment and research without prior consent processes, and practitioner motivation and strong leadership. Lack of leadership negatively affected practitioner engagement and recruitment. EcLiPSE completed on time, achieving its required sample size target. CONCLUSIONS: Successful trial recruitment and conduct in a challenging ED-led trial was driven by trial design, recruitment experience, teamwork and leadership. Our study provides valuable insight from parents and practitioners to inform the design and conduct of future trials in this setting.
Assuntos
Serviço Hospitalar de Emergência , Levetiracetam/uso terapêutico , Pais/psicologia , Fenitoína/uso terapêutico , Ensaios Clínicos Pragmáticos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Estado Epiléptico/tratamento farmacológico , Anticonvulsivantes/uso terapêutico , Criança , Coleta de Dados/métodos , Inglaterra , Feminino , Humanos , Masculino , Estudos Multicêntricos como AssuntoRESUMO
BACKGROUND: Convulsive status epilepticus is the most common neurological emergency in children. Its management is important to avoid or minimise neurological morbidity and death. The current first-choice second-line drug is phenytoin (Epanutin, Pfizer Inc., New York, NY, USA), for which there is no robust scientific evidence. OBJECTIVE: To determine whether phenytoin or levetiracetam (Keppra, UCB Pharma, Brussels, Belgium) is the more clinically effective intravenous second-line treatment of paediatric convulsive status epilepticus and to help better inform its management. DESIGN: A multicentre parallel-group randomised open-label superiority trial with a nested mixed-method study to assess recruitment and research without prior consent. SETTING: Participants were recruited from 30 paediatric emergency departments in the UK. PARTICIPANTS: Participants aged 6 months to 17 years 11 months, who were presenting with convulsive status epilepticus and were failing to respond to first-line treatment. INTERVENTIONS: Intravenous levetiracetam (40 mg/kg) or intravenous phenytoin (20 mg/kg). MAIN OUTCOME MEASURES: Primary outcome - time from randomisation to cessation of all visible signs of convulsive status epilepticus. Secondary outcomes - further anticonvulsants to manage the convulsive status epilepticus after the initial agent, the need for rapid sequence induction owing to ongoing convulsive status epilepticus, admission to critical care and serious adverse reactions. RESULTS: Between 17 July 2015 and 7 April 2018, 286 participants were randomised, treated and consented. A total of 152 participants were allocated to receive levetiracetam and 134 participants to receive phenytoin. Convulsive status epilepticus was terminated in 106 (70%) participants who were allocated to levetiracetam and 86 (64%) participants who were allocated to phenytoin. Median time from randomisation to convulsive status epilepticus cessation was 35 (interquartile range 20-not assessable) minutes in the levetiracetam group and 45 (interquartile range 24-not assessable) minutes in the phenytoin group (hazard ratio 1.20, 95% confidence interval 0.91 to 1.60; p = 0.2). Results were robust to prespecified sensitivity analyses, including time from treatment commencement to convulsive status epilepticus termination and competing risks. One phenytoin-treated participant experienced serious adverse reactions. LIMITATIONS: First, this was an open-label trial. A blinded design was considered too complex, in part because of the markedly different infusion rates of the two drugs. Second, there was subjectivity in the assessment of 'cessation of all signs of continuous, rhythmic clonic activity' as the primary outcome, rather than fixed time points to assess convulsive status epilepticus termination. However, site training included simulated demonstration of seizure cessation. Third, the time point of randomisation resulted in convulsive status epilepticus termination prior to administration of trial treatment in some cases. This affected both treatment arms equally and had been prespecified at the design stage. Last, safety measures were a secondary outcome, but the trial was not powered to demonstrate difference in serious adverse reactions between treatment groups. CONCLUSIONS: Levetiracetam was not statistically superior to phenytoin in convulsive status epilepticus termination rate, time taken to terminate convulsive status epilepticus or frequency of serious adverse reactions. The results suggest that it may be an alternative to phenytoin in the second-line management of paediatric convulsive status epilepticus. Simple trial design, bespoke site training and effective leadership were found to facilitate practitioner commitment to the trial and its success. We provide a framework to optimise recruitment discussions in paediatric emergency medicine trials. FUTURE WORK: Future work should include a meta-analysis of published studies and the possible sequential use of levetiracetam and phenytoin or sodium valproate in the second-line treatment of paediatric convulsive status epilepticus. TRIAL REGISTRATION: Current Controlled Trials ISRCTN22567894 and European Clinical Trials Database EudraCT number 2014-002188-13. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 58. See the NIHR Journals Library website for further project information.
Most epileptic tonicclonic seizures, also called convulsions, last for < 4 minutes and stop spontaneously. A convulsion that lasts for > 5 minutes is called convulsive status epilepticus. This may cause neurological abnormalities or, rarely, death. There is good scientific evidence for the best first-line medicine, called a benzodiazepine, to stop convulsive status epilepticus. When a benzodiazepine has not stopped status, a second-line medicine is given. The usual second-line medicine, which has been used for > 50 years, is phenytoin (Epanutin, Pfizer Inc., New York, NY, USA). However, it stops status in only half of children. It must be given slowly because it can cause unpleasant and potentially serious side effects. A new medicine called levetiracetam (Keppra, UCB Pharma, Brussels, Belgium) may be more effective. It seems to have less serious side effects than phenytoin. However, there is no good scientific evidence as to whether phenytoin or levetiracetam is better. A randomised controlled trial is the best scientific way to decide which of these two medicines is better. The Emergency treatment with Levetiracetam or Phenytoin in Status Epilepticus in children (EcLiPSE) trial was a randomised controlled trial that compared levetiracetam with phenytoin. A total of 152 children were randomised to receive levetiracetam and a total of 134 children were randomised to receive phenytoin. Research without prior consent was shown to be acceptable to parents, doctors and nurses. Parents' consent to use their child's data and continue in the trial was provided after the emergency situation was resolved. Convulsive status epilepticus stopped in 70.4% of the levetiracetam-treated children and in 64% of the phenytoin-treated children. The median time to status stopping was 35 minutes in the levetiracetam-treated children and 45 minutes in the phenytoin-treated children. Only one participant on phenytoin (vs. none on levetiracetam) experienced serious side effects that were thought to be caused by their treatment. None of the results showed any statistically significant or meaningful difference between levetiracetam and phenytoin. However, the results suggest that levetiracetam might be an alternative choice to phenytoin.
Assuntos
Anticonvulsivantes/uso terapêutico , Levetiracetam/uso terapêutico , Fenitoína/uso terapêutico , Estado Epiléptico/tratamento farmacológico , Administração Intravenosa , Adolescente , Anticonvulsivantes/administração & dosagem , Criança , Pré-Escolar , Estudos de Equivalência como Asunto , Feminino , Humanos , Lactente , Levetiracetam/administração & dosagem , Masculino , Fenitoína/administração & dosagem , Reino UnidoRESUMO
INTRODUCTION: Antiepileptic drugs (AEDs) are the mainstay of epilepsy treatment. Over the past 20 years, a number of new drugs have been approved for National Health Service (NHS) use on the basis of information from short-term trials that demonstrate efficacy. These trials do not provide information about the longer term outcomes, which inform treatment policy. This trial will assess the long-term clinical and cost-effectiveness of the newer treatment levetiracetam and zonisamide. METHODS AND ANALYSIS: This is a phase IV, multicentre, open-label, randomised, controlled clinical trial comparing new and standard treatments for patients with newly diagnosed epilepsy. Arm A of the trial randomised 990 patients with focal epilepsy to standard AED lamotrigine or new AED levetiracetam or zonisamide. Arm B randomised 520 patients with generalised epilepsy to standard AED sodium valproate or new AED levetiracetam. Patients are recruited from UK NHS outpatient epilepsy, general neurology and paediatric clinics. Included patients are aged 5 years or older with two or more spontaneous seizures requiring AED monotherapy, who are not previously treated with AEDs. Patients are followed up for a minimum of 2 years. The primary outcome is time to 12-month remission from seizures. Secondary outcomes include time to treatment failure (including due to inadequate seizure control or unacceptable adverse reactions); time to first seizure; time to 24-month remission; adverse reactions and quality of life. All primary analyses will be on an intention to treat basis. Separate analyses will be undertaken for each arm. Health economic analysis will be conducted from the perspective of the NHS to assess the cost-effectiveness of each AED. ETHICS AND DISSEMINATION: This trial has been approved by the North West-Liverpool East REC (Ref. 12/NW/0361). The trial team will disseminate the results through scientific meetings, peer-reviewed publications and patient and public involvement. TRIAL REGISTRATION NUMBERS: EudraCT 2012-001884-64; ISRCTN30294119.
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Anticonvulsivantes , Epilepsia , Anticonvulsivantes/uso terapêutico , Carbamazepina/uso terapêutico , Criança , Pré-Escolar , Ensaios Clínicos como Assunto , Análise Custo-Benefício , Epilepsia/tratamento farmacológico , Humanos , Levetiracetam/uso terapêutico , Estudos Multicêntricos como Assunto , Ensaios Clínicos Pragmáticos como Assunto , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Medicina Estatal , Zonisamida/uso terapêuticoRESUMO
BACKGROUND: Phenytoin is the recommended second-line intravenous anticonvulsant for treatment of paediatric convulsive status epilepticus in the UK; however, some evidence suggests that levetiracetam could be an effective and safer alternative. This trial compared the efficacy and safety of phenytoin and levetiracetam for second-line management of paediatric convulsive status epilepticus. METHODS: This open-label, randomised clinical trial was undertaken at 30 UK emergency departments at secondary and tertiary care centres. Participants aged 6 months to under 18 years, with convulsive status epilepticus requiring second-line treatment, were randomly assigned (1:1) using a computer-generated randomisation schedule to receive levetiracetam (40 mg/kg over 5 min) or phenytoin (20 mg/kg over at least 20 min), stratified by centre. The primary outcome was time from randomisation to cessation of convulsive status epilepticus, analysed in the modified intention-to-treat population (excluding those who did not require second-line treatment after randomisation and those who did not provide consent). This trial is registered with ISRCTN, number ISRCTN22567894. FINDINGS: Between July 17, 2015, and April 7, 2018, 1432 patients were assessed for eligibility. After exclusion of ineligible patients, 404 patients were randomly assigned. After exclusion of those who did not require second-line treatment and those who did not consent, 286 randomised participants were treated and had available data: 152 allocated to levetiracetam, and 134 to phenytoin. Convulsive status epilepticus was terminated in 106 (70%) children in the levetiracetam group and in 86 (64%) in the phenytoin group. Median time from randomisation to cessation of convulsive status epilepticus was 35 min (IQR 20 to not assessable) in the levetiracetam group and 45 min (24 to not assessable) in the phenytoin group (hazard ratio 1·20, 95% CI 0·91-1·60; p=0·20). One participant who received levetiracetam followed by phenytoin died as a result of catastrophic cerebral oedema unrelated to either treatment. One participant who received phenytoin had serious adverse reactions related to study treatment (hypotension considered to be immediately life-threatening [a serious adverse reaction] and increased focal seizures and decreased consciousness considered to be medically significant [a suspected unexpected serious adverse reaction]). INTERPRETATION: Although levetiracetam was not significantly superior to phenytoin, the results, together with previously reported safety profiles and comparative ease of administration of levetiracetam, suggest it could be an appropriate alternative to phenytoin as the first-choice, second-line anticonvulsant in the treatment of paediatric convulsive status epilepticus. FUNDING: National Institute for Health Research Health Technology Assessment programme.
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Anticonvulsivantes/administração & dosagem , Levetiracetam/administração & dosagem , Fenitoína/administração & dosagem , Estado Epiléptico/tratamento farmacológico , Adolescente , Anticonvulsivantes/efeitos adversos , Criança , Pré-Escolar , Esquema de Medicação , Epilepsia Resistente a Medicamentos/tratamento farmacológico , Serviço Hospitalar de Emergência , Feminino , Humanos , Lactente , Levetiracetam/efeitos adversos , Masculino , Fenitoína/efeitos adversos , Resultado do Tratamento , Reino UnidoRESUMO
BACKGROUND: EcLiPSE (Emergency treatment with Levetiracetam or Phenytoin in Status Epilepticus in children) is a randomised controlled trial (RCT) in the United Kingdom. Challenges to success include the need to immediately administer an intervention without informed consent and changes in staffing during trial conduct, mainly due to physician rotations. Using literature on parents' perspectives and research without prior consent (RWPC) guidance, we developed an interactive training package (including videos, simulation and question and answer sessions) and evaluated its dissemination and impact upon on practitioners' confidence in recruitment and consent. METHODS: Questionnaires were administered before and immediately after training followed by telephone interviews (mean 11 months later), focus groups (mean 14 months later) and an online questionnaire (8 months before trial closure). RESULTS: One hundred and twenty-five practitioners from 26/30 (87%) participating hospitals completed a questionnaire before and after training. We conducted 10 interviews and six focus groups (comprising 36 practitioners); 199 practitioners working in all recruiting hospitals completed the online questionnaire. Before training, practitioners were concerned about recruitment and consent. Confidence increased after training for explaining (all scale 0-5, 95% CIs above 0 and p values < 0.05): the study (66% improved mean score before 3.28 and after 4.52), randomisation (47% improvement, 3.86 to 4.63), RWPC (72% improvement, 2.98 to 4.39), and addressing parents' objections to randomisation (51% improvement, 3.37 to 4.25). Practitioners rated highly the content and clarity of the training, which was successfully disseminated. Some concerns about staff availability for training and consent discussions remained. CONCLUSIONS: Training improved practitioners' confidence in recruitment and RWPC. Our findings highlight the value of using parents' perspectives to inform training and to engage practitioners in trials that are at high risk of being too challenging to conduct.
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Emergências , Consentimento Livre e Esclarecido , Levetiracetam/uso terapêutico , Seleção de Pacientes , Fenitoína/uso terapêutico , Estado Epiléptico/tratamento farmacológico , Humanos , Projetos de PesquisaRESUMO
Objective evidence is limited for the value of transition programs for youth with chronic illness moving from pediatric to adult care; however, such programs intuitively "make sense". We describe the strengths and weaknesses of a variety of transition programs from around the world for adolescents with epilepsy. Consequences of poorly organized transition beyond suboptimal seizure control may include an increased risk of sudden unexpected death in epilepsy (SUDEP), poor psychological and social outcome, and inadequate management of comorbidities. The content of transition programs for those with normal intelligence differs from those with intellectual disability, but both groups may benefit from an emphasis on sporting activities. Concerns that may interfere with optimal transition include lack of nursing or social work services, limited numbers of adult neurologists/epileptologists confident in the treatment of complex pediatric epilepsy problems, institutional financial support, and time constraints for pediatric and adult physicians who treat epilepsy and the provision of multidisciplinary care. Successful programs eventually need to rely on a several adult physicians, nurses, and other key healthcare providers and use novel approaches to complex care. More research is needed to document the value and effectiveness of transition programs for youth with epilepsy to persuade institutions and healthcare professionals to support these ventures.
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Comportamento do Adolescente/psicologia , Epilepsia/psicologia , Epilepsia/terapia , Educação de Pacientes como Assunto/métodos , Transição para Assistência do Adulto , Adolescente , Adulto , Criança , Comorbidade , Humanos , Neurologistas/psicologia , Médicos/psicologiaRESUMO
Cerebral palsy (CP) is not a disease, but a neurological syndrome, a combination of signs and symptoms, some of which may occur in neurodegenerative or metabolic disorders, particularly those with an onset in the first 2 years of life. There are many different causes of the syndrome. All children with CP should undergo brain MRI, even with an identified antenatal or perinatal insult. Children with CP should be referred to a paediatric neurologist or a clinical geneticist, or both, if appropriate and particularly in the absence of a known perinatal cerebral insult, with brain MRI that is reported to be normal, a progression in, or new, signs or where there is a reported 'family history of CP'. Finally, a few of the CP syndromes may be readily treatable and potentially prevent irreversible neurological and cognitive impairment.
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Paralisia Cerebral/diagnóstico , Ataxia/etiologia , Paralisia Cerebral/genética , Criança , Pré-Escolar , Diagnóstico Diferencial , Distonia/etiologia , Humanos , Debilidade Muscular/etiologia , Mutação/genética , Transtornos Psicomotores/etiologia , Quadriplegia/etiologiaRESUMO
OBJECTIVES: We explored children's views on research without prior consent (RWPC) and sought to identify ways of involving children in research discussions. DESIGN: Qualitative interview study. SETTING: Participants were recruited through a UK children's hospital and online advertising. PARTICIPANTS: 16 children aged 7-15 years with a diagnosis of asthma (n=14) or anaphylaxis (n=2) with recent (<12 months) experience of emergency care. RESULTS: Children were keen to be included in medical research and viewed RWPC as acceptable in emergency situations if trial interventions were judged safe. Children trusted that doctors would know about their trial participation and act in their best interests. All felt that children should be informed about the research following their recovery and involved in discussions with a clinician or their parent(s) about the use of data already collected as well as continued participation in the trial (if applicable). Participants suggested methods to inform children about their trial participation including an animation. CONCLUSIONS: Children supported, and were keen to be involved in, clinical trials in emergency situations. We present guidance and an animation that practitioners and parents might use to involve children in trial discussions following their recovery.
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Asma/psicologia , Pesquisa Biomédica/legislação & jurisprudência , Tratamento de Emergência , Consentimento Livre e Esclarecido/ética , Pais/psicologia , Adolescente , Criança , Feminino , Humanos , Entrevistas como Assunto , Masculino , Médicos/psicologia , Relações Profissional-Paciente , Pesquisa Qualitativa , Reino UnidoRESUMO
PURPOSE: To compare the de novo incidence of Panayiotopoulos syndrome (PS, early-onset childhood occipital epilepsy) and a common epilepsy syndrome, benign epilepsy with centro-temporal spikes (BECTS), in children and young people. METHODS: The incidence of PS and BECTS was recorded over 16 months in a population of children and young people (aged <16â¯years) living within a specific geographic area and epilepsy network within the North West of England and North Wales and the catchment area of the tertiary paediatric epilepsy centre. Monthly data collection proformas were circulated to the paediatricians and paediatric neurologists responsible for the evaluation of epilepsy in children within this area. This also included monthly reminders of the electro-clinical criteria for these syndromes. EEGs were undertaken in the neurophysiology department of the tertiary paediatric epilepsy centre. The departmental EEG database on all <16â¯year olds that underwent an EEG during the study period was examined to identify additional patients that may not have been reported via a proforma-reporting system. RESULTS: The incidence of PS and BECTS was found to be 0.8 and 6.1 per 100,000 <16â¯year olds, respectively. The ages at seizure onset and diagnosis were similar for BECTS and PS. CONCLUSION: This study is the first to determine a comparative incidence of PS and BECTS. The findings suggest BECTS is eight times more common than PS and that the incidence of PS is lower than previously suggested.
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Encéfalo/fisiopatologia , Epilepsias Parciais/epidemiologia , Epilepsias Parciais/fisiopatologia , Epilepsia Mioclônica Juvenil/epidemiologia , Epilepsia Mioclônica Juvenil/fisiopatologia , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Eletroencefalografia , Epilepsias Parciais/diagnóstico , Humanos , Incidência , Lactente , Epilepsia Mioclônica Juvenil/diagnósticoRESUMO
OBJECTIVE: To evaluate the safety and preliminary pharmacokinetics of a pharmaceutical formulation of purified cannabidiol (CBD) in children with Dravet syndrome. METHODS: Patients aged 4-10 years were randomized 4:1 to CBD (5, 10, or 20 mg/kg/d) or placebo taken twice daily. The double-blind trial comprised 4-week baseline, 3-week treatment (including titration), 10-day taper, and 4-week follow-up periods. Completers could continue in an open-label extension. Multiple pharmacokinetic blood samples were taken on the first day of dosing and at end of treatment for measurement of CBD, its metabolites 6-OH-CBD, 7-OH-CBD, and 7-COOH-CBD, and antiepileptic drugs (AEDs; clobazam and metabolite N-desmethylclobazam [N-CLB], valproate, levetiracetam, topiramate, and stiripentol). Safety assessments were clinical laboratory tests, physical examinations, vital signs, ECGs, adverse events (AEs), seizure frequency, and suicidality. RESULTS: Thirty-four patients were randomized (10, 8, and 9 to the 5, 10, and 20 mg/kg/d CBD groups, and 7 to placebo); 32 (94%) completed treatment. Exposure to CBD and its metabolites was dose-proportional (AUC0-t). CBD did not affect concomitant AED levels, apart from an increase in N-CLB (except in patients taking stiripentol). The most common AEs on CBD were pyrexia, somnolence, decreased appetite, sedation, vomiting, ataxia, and abnormal behavior. Six patients taking CBD and valproate developed elevated transaminases; none met criteria for drug-induced liver injury and all recovered. No other clinically relevant safety signals were observed. CONCLUSIONS: Exposure to CBD and its metabolites increased proportionally with dose. An interaction with N-CLB was observed, likely related to CBD inhibition of cytochrome P450 subtype 2C19. CBD resulted in more AEs than placebo but was generally well-tolerated. CLASSIFICATION OF EVIDENCE: This study provides Class I evidence that for children with Dravet syndrome, CBD resulted in more AEs than placebo but was generally well-tolerated.
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Anticonvulsivantes/uso terapêutico , Canabidiol/uso terapêutico , Epilepsias Mioclônicas/tratamento farmacológico , Anticonvulsivantes/efeitos adversos , Anticonvulsivantes/farmacocinética , Benzodiazepinas/farmacocinética , Benzodiazepinas/uso terapêutico , Canabidiol/efeitos adversos , Canabidiol/farmacocinética , Criança , Pré-Escolar , Clobazam/farmacocinética , Clobazam/uso terapêutico , Relação Dose-Resposta a Droga , Método Duplo-Cego , Quimioterapia Combinada , Epilepsias Mioclônicas/sangue , Seguimentos , Humanos , Resultado do TratamentoRESUMO
BACKGROUND: Tonic-clonic convulsions and convulsive status epilepticus (currently defined as a tonic-clonic convulsion lasting at least 30 minutes) are medical emergencies and require urgent and appropriate anticonvulsant treatment. International consensus is that an anticonvulsant drug should be administered for any tonic-clonic convulsion that has been continuing for at least five minutes. Benzodiazepines (diazepam, lorazepam, midazolam) are traditionally regarded as first-line drugs and phenobarbital, phenytoin and paraldehyde as second-line drugs. This is an update of a Cochrane Review first published in 2002 and updated in 2008. OBJECTIVES: To evaluate the effectiveness and safety of anticonvulsant drugs used to treat any acute tonic-clonic convulsion of any duration, including established convulsive (tonic-clonic) status epilepticus in children who present to a hospital or emergency medical department. SEARCH METHODS: For the latest update we searched the Cochrane Epilepsy Group's Specialised Register (23 May 2017), the Cochrane Central Register of Controlled Trials (CENTRAL) via the Cochrane Register of Studies Online (CRSO, 23 May 2017), MEDLINE (Ovid, 1946 to 23 May 2017), ClinicalTrials.gov (23 May 2017), and the WHO International Clinical Trials Registry Platform (ICTRP, 23 May 2017). SELECTION CRITERIA: Randomised and quasi-randomised trials comparing any anticonvulsant drugs used for the treatment of an acute tonic-clonic convulsion including convulsive status epilepticus in children. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trials for inclusion and extracted data. We contacted study authors for additional information. MAIN RESULTS: The review includes 18 randomised trials involving 2199 participants, and a range of drug treatment options, doses and routes of administration (rectal, buccal, nasal, intramuscular and intravenous). The studies vary by design, setting and population, both in terms of their ages and also in their clinical situation. We have made many comparisons of drugs and of routes of administration of drugs in this review; our key findings are as follows:(1) This review provides only low- to very low-quality evidence comparing buccal midazolam with rectal diazepam for the treatment of acute tonic-clonic convulsions (risk ratio (RR) for seizure cessation 1.25, 95% confidence interval (CI) 1.13 to 1.38; 4 trials; 690 children). However, there is uncertainty about the effect and therefore insufficient evidence to support its use. There were no included studies which compare intranasal and buccal midazolam.(2) Buccal and intranasal anticonvulsants were shown to lead to similar rates of seizure cessation as intravenous anticonvulsants, e.g. intranasal lorazepam appears to be as effective as intravenous lorazepam (RR 0.96, 95% CI 0.82 to 1.13; 1 trial; 141 children; high-quality evidence) and intranasal midazolam was equivalent to intravenous diazepam (RR 0.98, 95% CI 0.91 to 1.06; 2 trials; 122 children; moderate-quality evidence).(3) Intramuscular midazolam also showed a similar rate of seizure cessation to intravenous diazepam (RR 0.97, 95% CI 0.87 to 1.09; 2 trials; 105 children; low-quality evidence).(4) For intravenous routes of administration, lorazepam appears to be as effective as diazepam in stopping acute tonic clonic convulsions: RR 1.04, 95% CI 0.94 to 1.16; 3 trials; 414 children; low-quality evidence. Furthermore, we found no statistically significant or clinically important differences between intravenous midazolam and diazepam (RR for seizure cessation 1.08, 95% CI 0.97 to 1.21; 1 trial; 80 children; moderate-quality evidence) or intravenous midazolam and lorazepam (RR for seizure cessation 0.98, 95% CI 0.91 to 1.04; 1 trial; 80 children; moderate-quality evidence). In general, intravenously-administered anticonvulsants led to more rapid seizure cessation but this was usually compromised by the time taken to establish intravenous access.(5) There is limited evidence from a single trial to suggest that intranasal lorazepam may be more effective than intramuscular paraldehyde in stopping acute tonic-clonic convulsions (RR 1.22, 95% CI 0.99 to 1.52; 160 children; moderate-quality evidence).(6) Adverse side effects were observed and reported very infrequently in the included studies. Respiratory depression was the most common and most clinically relevant side effect and, where reported, the frequency of this adverse event was observed in 0% to up to 18% of children. None of the studies individually demonstrated any difference in the rates of respiratory depression between the different anticonvulsants or their different routes of administration; but when pooled, three studies (439 children) provided moderate-quality evidence that lorazepam was significantly associated with fewer occurrences of respiratory depression than diazepam (RR 0.72, 95% CI 0.55 to 0.93).Much of the evidence provided in this review is of mostly moderate to high quality. However, the quality of the evidence provided for some important outcomes is low to very low, particularly for comparisons of non-intravenous routes of drug administration. Low- to very low-quality evidence was provided where limited data and imprecise results were available for analysis, methodological inadequacies were present in some studies which may have introduced bias into the results, study settings were not applicable to wider clinical practice, and where inconsistency was present in some pooled analyses. AUTHORS' CONCLUSIONS: We have not identified any new high-quality evidence on the efficacy or safety of an anticonvulsant in stopping an acute tonic-clonic convulsion that would inform clinical practice. There appears to be a very low risk of adverse events, specifically respiratory depression. Intravenous lorazepam and diazepam appear to be associated with similar rates of seizure cessation and respiratory depression. Although intravenous lorazepam and intravenous diazepam lead to more rapid seizure cessation, the time taken to obtain intravenous access may undermine this effect. In the absence of intravenous access, buccal midazolam or rectal diazepam are therefore acceptable first-line anticonvulsants for the treatment of an acute tonic-clonic convulsion that has lasted at least five minutes. There is no evidence provided by this review to support the use of intranasal midazolam or lorazepam as alternatives to buccal midazolam or rectal diazepam.
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Anticonvulsivantes/uso terapêutico , Epilepsia Tônico-Clônica/tratamento farmacológico , Estado Epiléptico/tratamento farmacológico , Administração por Inalação , Administração Oral , Administração Retal , Anticonvulsivantes/administração & dosagem , Criança , Diazepam/administração & dosagem , Humanos , Injeções Intramusculares , Injeções Intravenosas , Lorazepam/administração & dosagem , Midazolam/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
OBJECTIVE: To characterize the phenotypic spectrum, molecular genetic findings, and functional consequences of pathogenic variants in early-onset KCNT1 epilepsy. METHODS: We identified a cohort of 31 patients with epilepsy of infancy with migrating focal seizures (EIMFS) and screened for variants in KCNT1 using direct Sanger sequencing, a multiple-gene next-generation sequencing panel, and whole-exome sequencing. Additional patients with non-EIMFS early-onset epilepsy in whom we identified KCNT1 variants on local diagnostic multiple gene panel testing were also included. When possible, we performed homology modeling to predict the putative effects of variants on protein structure and function. We undertook electrophysiologic assessment of mutant KCNT1 channels in a xenopus oocyte model system. RESULTS: We identified pathogenic variants in KCNT1 in 12 patients, 4 of which are novel. Most variants occurred de novo. Ten patients had a clinical diagnosis of EIMFS, and the other 2 presented with early-onset severe nocturnal frontal lobe seizures. Three patients had a trial of quinidine with good clinical response in 1 patient. Computational modeling analysis implicates abnormal pore function (F346L) and impaired tetramer formation (F502V) as putative disease mechanisms. All evaluated KCNT1 variants resulted in marked gain of function with significantly increased channel amplitude and variable blockade by quinidine. CONCLUSIONS: Gain-of-function KCNT1 pathogenic variants cause a spectrum of severe focal epilepsies with onset in early infancy. Currently, genotype-phenotype correlations are unclear, although clinical outcome is poor for the majority of cases. Further elucidation of disease mechanisms may facilitate the development of targeted treatments, much needed for this pharmacoresistant genetic epilepsy.