Mutations in PRRT2 are not a common cause of infantile epileptic encephalopathies

Heterozygous mutations in PRRT2 have recently been identified as the major cause of autosomal dominant benign familial infantile epilepsy (BFIE), infantile convulsions with choreoathetosis syndrome (ICCA), and paroxysmal kinesigenic dyskinesia (PKD). Homozygous mutations in PRRT2 have also been reported in two families with intellectual disability (ID) and seizures. Heterozygous mutations in the genes KCNQ2 and SCN2A cause the two other autosomal dominant seizure disorders of infancy: benign familial neonatal epilepsy and benign familial neonatal‐infantile epilepsy. Mutations in KCNQ2 and SCN2A also contribute to severe infantile epileptic encephalopathies (IEEs) in which seizures and intellectual disability co‐occur. We therefore hypothesized that PRRT2 mutations may also underlie cases of IEE. We examined PRRT2 for heterozygous, compound heterozygous or homozygous mutations to determine their frequency in causing epileptic encephalopathies (EEs). Two hundred twenty patients with EEs with onset by 2 years were phenotyped. An assay for the common PRRT2 c.649‐650insC mutation and high resolution‐melt analysis for mutations in the remaining exons of PRRT2 were performed. Neither the common mutation nor any other pathogenic variants in PRRT2 were detected in the 220 patients. Our findings suggest that mutations in PRRT2 are not a common cause of IEEs.     

Long-term seizure outcome and antiepileptic drug treatment in surgically treated temporal lobe epilepsy patients: a controlled study

PURPOSE: To evaluate the long-term impact of surgical treatment on seizure outcome and antiepileptic drug (AED) use in patients with pharmacoresistant temporal lobe epilepsy (TLE). METHODS: Comparison of seizure outcome and AED us in operated-on TLE patients (n=148) and nonsurgically treated TLE patients (n=94) at a baseline visit and a follow-up visit after a mean period of 4.8 years. RESULTS: At follow-up, 44.6% of the surgical patients and 4.3% of the nonsurgical patients had been continuously seizure- free since the baseline visit (including the immediate postoperative period). A further 17.6% of the operated-on and 3.2% of the not operated-on patients had been seizure-free for at least the previous year; 37.8% of the surgical and 92.5% of the nonsurgical patients had had seizures during the previous 12 months (p < 0.001). Of the surgical patients, 8.8% versus none of the nonsurgical patients were AED free at follow-up; 55.4% versus 20.2% were receiving monotherapy, and 35.8% versus 79.8% were receiving polytherapy (p < 0.001). Mean number of AEDs and mean change in number of AEDs were significantly more favorable in operated-on than in non-operated-on patients. Further subgroup analysis revealed that not only the continuously seizure-free surgical patients, but also the operated-on patients with ongoing seizures took fewer AEDs than their respective non-operated-on counterparts. CONCLUSIONS: This controlled study for the first time provides comprehensive information on long-term seizure outcome and AED use in surgical TLE patients. It shows a more favorable seizure outcome and AED use in the surgically treated patients. The latter holds true even for the not seizure-free patient subgroup.     

Epileptic encephalopathies: Optimizing seizure control and developmental outcome

Cognitive and developmental outcomes in patients with epileptic encephalopathy are hypothesized to result from an interplay between the underlying epileptic pathologic substrate and the acquired consequences of frequent and repetitive seizures and epileptiform discharges that often straddle the interictal and ictal boundaries. This article briefly reviews the evidence related to this assumption, presents critical questions that need to be answered to clarify this relationship, and advances a set of concrete steps that may help improve developmental patient outcomes.     

Dystonia as a prominent presenting feature in developmental and epileptic encephalopathies: A case series

IntroductionAlthough there has been increasing recognition of the occurrence of non-epileptic involuntary movements in developmental and epileptic encephalopathies (DEEs), the spectrum of dystonic presentations associated with these conditions remains poorly described. We sought to expand the catalogue of dystonia-predominant phenotypes in monogenic DEEs, building on the recently introduced concept of an epilepsy-movement disorder spectrum.MethodsCases were identified from a whole-exome-sequenced cohort of 45 pediatric index patients with complex dystonia (67% sequenced as parent-child trios). Review of molecular findings in DEE-associated genes was performed. For five individuals with identified DEE-causing variants, detailed information about presenting phenotypic features and the natural history of disease was obtained.ResultsDe-novo pathogenic and likely pathogenic missense variants in GABRA1, GABBR2, GNAO1, and FOXG1 gave rise to infantile-onset persistent and paroxysmal dystonic manifestations, beginning in the limb or truncal musculature and progressing gradually to a generalized state. Coexisting, less prominent movement-disorder symptoms were observed and included myoclonic, ballistic, and stereotypic abnormal movements as well as choreoathetosis. Dystonia dominated over epileptic neurodevelopmental comorbidities in all four subjects and represented the primary indication for molecular genetic analysis. We also report the unusual case of an adult female patient with dystonia, tremor, and mild learning disability who was found to harbor a pathogenic frameshift variant in MECP2.ConclusionsDystonia can be a leading clinical manifestation in different DEEs. A monogenic basis of disease should be considered on the association of dystonia and developmental delay-epilepsy presentations, justifying a molecular screening for variants in DEE-associated genes.     

Additional observation of a de novo pathogenic variant in KCNT2 leading to epileptic encephalopathy with clinical features of frontal lobe epilepsy

IntroductionKCNT2 was recently recognized as a gene associated with neurodevelopmental disorder and epilepsy.Case reportWe present an additional observation of a 16-year-old male patient with a novel de novo KCNT2 likely pathogenic variant and review the five previously reported cases of de novo variants in this gene.DiscussionWhole exome sequencing identified the missense variant c.725C > A p.(Thr242Asn), which was confirmed by Sanger sequencing. Our patient has a refractory stereotyped and monomorphic type of hyperkinetic focal motor seizure, similar to what is seen in frontal lobe epilepsy, occurring only during sleep. This type of seizure is not usually seen in epileptic encephalopathies.     

Effective treatments for FGF12-related early-onset epileptic encephalopathies patients

BackgroundFGF12 (FHF1) gene encodes voltage-gated sodium channel (Nav)-binding protein fibroblast growth factor homologous factor 1, which could cause seizures by regulating voltage dependence of Nav fast inactivation and neuron excitability. The most common pathogenic variant FGF12 c.341G > A related early-onset epileptic encephalopathies (EOEE) was characterized by intractable seizures and developmental disabilities.ResultsUsing whole exome sequencing, a de novo hotspot variant c.341G > A (NM_021032.4) of FGF12 was identified in three unrelated EOEE probands. All probands were seizure free after a combination treatment of valproic acid (VPA) and topiramate (TPM). The motor and cognitive skills in two probands were improved due to the early and effective treatment. In order to compare the effectiveness of different treatment strategies for the disease, a review of treatments for FGF12-related epilepsy was made.ConclusionWe reported three FGF12 c.341G > A related EOEE patients responded well to a combination antiepileptic therapy of VPA and TPM. The current study is the first to describe the combination therapy of VPA and TPM in FGF12 c.341G > A related EOEE patients. This study may contribute to future medication consultation for intractable epilepsy with FGF12 hotspot variants.     

Long-term developmental outcome in patients with West syndrome after epilepsy surgery

It has been hypothesized that early seizure control may prevent children with intractable epileptic spasms (ES) from developmental regression and may contribute to better developmental outcome. The effectiveness of surgery for ES has been reported. We investigated long-term post-operative outcomes of seizure control and development in patients with symptomatic West syndrome (S-WS) who underwent epilepsy surgery. Six children who underwent surgical intervention for intractable ES were retrospectively investigated. Cortical malformations were observed on pre-operative MRI in all patients, with hemispheric or multilobar involvement in four children and focal lesions in two. Following surgery, we measured motor function, developmental age (DA), language skills, and sociopsychological function for up to 7years (mean, 4.9years). Post-operative seizure outcome was Engel Class I (n=4) or III (n=2). Motor function and DA was increased following surgery in six and five patients, respectively. Two patients started to speak in sentences following focal resection. Autistic features were noted in four of the five examined patients post-operatively. None of the patients showed developmental regression following surgery. Epilepsy surgery for S-WS with ES may result in good seizure control and improvement in motor development. Improvement in cognitive function was modest in this small cohort of children and autistic features were noted post-operatively in a substantial proportion of the children. While seizure control can be obtained by epilepsy surgery, early intervention for sociopsychological comorbidities may be warranted in children with S-WS.     

Epileptic and nonepileptic features in patients with early onset epileptic encephalopathy and STXBP1 mutations

Purpose: STXBP1 (MUNC18‐1) mutations have been associated with various types of epilepsies, mostly beginning early in life. To refine the phenotype associated with STXBP1 aberrations in early onset epileptic syndromes, we studied this gene in a cohort of patients with early onset epileptic encephalopathy. Methods: STXBP1 was screened in a multicenter cohort of 52 patients with early onset epilepsy (first seizure observed before the age of 3 months), no cortical malformation on brain magnetic resonance imaging (MRI), and negative metabolic screening. Three groups of patients could be distinguished in this cohort: (1) Ohtahara syndromes (n = 38); (2) early myoclonic encephalopathies (n = 7); and (3) early onset epileptic encephalopathies that did not match any familiar syndrome (n = 7). None of the patients displayed any cortical malformation on brain MRI and all were screened through multiple video–electroencephalography (EEG) recordings for a time period spanning from birth to their sixth postnatal month. Subsequently, patients had standard EEG or video‐EEG recordings. Key Findings: We found five novel STXBP1 mutations in patients for whom video‐EEG recordings could be sampled from the beginning of the disease. All patients with a mutation displayed Ohtahara syndrome, since most early seizures could be classified as epileptic spasms and since the silent EEG periods were on average shorter than bursts. However, each patient in addition displayed a particular clinical and EEG feature: In two patients, early seizures were clonic, with very early EEG studies exhibiting relatively low amplitude bursts of activity before progressing into a typical suppression‐burst pattern, whereas the three other patients displayed epileptic spasms associated with typical suppression‐burst patterns starting from the early recordings. Epilepsy dramatically improved after 6 months and finally disappeared before the end of the first year of life for four patients; the remaining one patient had few seizures until 18 months of age. In parallel, EEG paroxysmal abnormalities disappeared in three patients and decreased in two, giving place to continuous activity with fast rhythms. Each patient displayed frequent nonepileptic movement disorders that could easily be mistaken for epileptic seizures. These movements could be observed as early as the neonatal period and, unlike seizures, persisted during all the follow‐up period. Significance: We confirm that STXBP1 is a major gene to screen in cases of Ohtahara syndrome, since it is mutated in >10% of the Ohtahara patients within our cohort. This gene should particularly be tested in the case of a surprising evolution of the patient condition if epileptic seizures and EEG paroxysmal activity disappear and are replaced by fast rhythms after the end of the first postnatal year.     

Long-term neurological and neuropsychological outcome in patients with severe traumatic brain injury

Background

Severe traumatic brain injury (TBI) remains a major cause of death and disability worldwide. The aim of the study was to evaluate predictors for neurological and neuropsychological long-term outcome in patients with severe TBI treated according to an intracranial pressure (ICP-) targeted therapy.

Methods

From 08/2005 to 12/2008, 46 patients with severe TBI and more than 12 h of intensive care treatment were included in this study. Neurological outcome was assessed with the Glasgow Outcome Scale (GOS). Neuropsychological performance assessing 9 different domains was evaluated at long-term follow-up (median 20.5 months; range 10–46). Logistic regression was used to identify favourable outcomes according to the GOS and Fisher's exact tests were used to identify predictors of severe neuropsychological impairments at follow-up.

Results

Twenty-nine patients were available for neuropsychological assessment at long-term follow-up. Only 2 out of 29 patients presented normal or average neuropsychological findings throughout all 9 neuropsychological domains at long-term follow-up. The percentage of a favourable outcome (GOS 4-5) increased from 13.8% at hospital discharge to 75.8% at rehabilitation discharge to 79.3% at long-term follow-up, respectively. Age ≤40 was found to be a strong predictor of favourable outcome at follow-up (OR 5.95, 95% CI 1.41 25.00, p = 0.015). The GOS at hospital discharge was not a predictor for severe impairments in any of the 9 different neuropsychological domains (all p-values were p > 0.268). In contrast, the GOS at rehabilitation discharge was found to be a predictor of severe impairments at follow-up in all but one domain assessed (all p-values less than p < 0.038).

Conclusions

The GOS at rehabilitation discharge should be regarded as a better predictor for neuropsychological impairments at long-term follow-up than the GOS at hospital discharge. Even in patients with favourable GOS after finishing a course of rehabilitation, three quarters of these patients may have at least one severe neuropsychological deficit. Therefore, it remains of paramount importance to provide long-term neuropsychological support to further improve outcome after TBI.     

特发性突聋远期预后的临床观察

目的探讨特发性突聋远期预后与近期预后之间的差异,评价当前综合治疗对远期预后的影响。方法 24例患者分别于入院、出院及出院后〉6个月分别进行纯音听阈检测。以出院时听力状态为近期预后指标,出院后〉6个月时听力状态为远期预后指标。远期预后与近期预后的比较采用非参数秩和检验。结果近期有效率为45.8%,远期好转率为62.5%,差异有统计学意义（P〈0.05）。结论特发性突聋远期预后与近期预后不同,远期预后优于近期预后,患者的听力恢复是一个漫长的过程。     

Malaysian outcome of acute necrotising encephalopathy of childhood

ObjectiveDescribe the outcome of a Malaysian cohort of children with acute necrotising encephalopathy (ANE).MethodRetrospective study of children with ANE seen at University of Malaya Medical Centre from 2014 to 2019. All clinical details including ANE-severity score (ANE-SS), immunomodulation treatment and neurodevelopmental long-term outcome were collected.ResultsThirteen patients had ANE and brainstem death occurred in 5. In 10 patients (77%) viruses were isolated contributing to ANE: 8 influenza virus, 1 acute dengue infection, and 1 acute varicella zoster infection. The ANE-SS ranged 2–7: 9 were high risk and 4 were medium risk. Among the 8 survivors; 1 was lost to follow-up. Follow-up duration was 1–6 years (median 2.2). At follow-up among the 4 high-risk ANE-SS: 2 who were in a vegetative state, 1 remained unchanged and 1 improved to severe disability; the other 2 with severe disability improved to moderate and mild disability respectively. At follow-up all 3 medium-risk ANE-SS improved: 2 with severe disability improved to moderate and mild disability respectively, while 1 in a vegetative state improved to severe disability. Early treatment with immunomodulation did not affect outcome.ConclusionOur ANE series reiterates that ANE is a serious cause of encephalopathy with mortality of 38.5%. All survivors were in a vegetative state or had severe disability at discharge. Most of the survivors made a degree of recovery but good recovery was seen in 2. Follow-up of at least 12 months is recommended for accurate prognostication. Dengue virus infection needs to be considered in dengue endemic areas.     

Long-term outcome and predictors of resective surgery prognosis in patients with refractory extratemporal epilepsy

PurposeWe analyzed the long-term postoperative outcome and possible predictive factors of the outcome in surgically treated patients with refractory extratemporal epilepsy.MethodsWe retrospectively analyzed 73 patients who had undergone resective surgery at the Epilepsy Center Brno between 1995 and 2010 and who had reached at least 1 year outcome after the surgery. The average age at surgery was 28.3 ± 11.4 years. Magnetic resonance imaging (MRI) did not reveal any lesion in 24 patients (32.9%). Surgical outcome was assessed annually using Engel's modified classification until 5 years after surgery and at the latest follow-up visit.ResultsFollowing the surgery, Engel Class I outcome was found in 52.1% of patients after 1 year, in 55.0% after 5 years, and in 50.7% at the last follow-up visit (average 6.15 ± 3.84 years). Of the patients who reached the 5-year follow-up visit (average of the last follow-up 9.23 years), 37.5% were classified as Engel IA at each follow-up visit. Tumorous etiology and lesions seen in preoperative MRI were associated with significantly better outcome (p = 0.035; p < 0.01). Postoperatively, 9.6% patients had permanent neurological deficits.ConclusionSurgical treatment of refractory extratemporal epilepsy is an effective procedure. The presence of a visible MRI-detected lesion and tumorous etiology is associated with significantly better outcome than the absence of MRI-detected lesion or other etiology.     

Corticosteroids as treatment of epileptic syndromes with continuous spike-waves during slow-wave sleep

To assess the efficacy and tolerability of steroids in epileptic syndromes with continuous spike-waves during slow-wave sleep (CSWS), charts of 44 children (25 boys) who received corticosteroids for cognitive and/or behavioral deterioration associated with CSWS were retrospectively reviewed. Awake and sleep electroencephalography (EEG) records, clinical and neuropsychological assessments were available before, during, and after corticosteroid therapy. Evaluation focused on effects on EEG, behavior, and cognition. All but two patients received hydrocortisone (initial dose of 5 mg/kg/day). The treatment was slowly tapered with a total duration of 21 months. There were 18 symptomatic and 26 cryptogenic cases. Mean age was 7 years and mean intelligence quotient/developmental quotient (IQ/DQ) was 65. Mean CSWS duration before corticosteroid treatment was 1.7 years. Twenty patients had tried more than two antiepileptic drugs (AEDs) before steroids. Positive response to steroids was found during the first 3 months of treatment in 34 of 44 patients (77.2%), with normalization of the EEG in 21 patients. Relapse occurred in 14 of them. Hence, 20 patients (45.4%) were long-term responders after a single but prolonged trial of steroids, including all four cases of Landau-Kleffner syndrome. Positive response to steroids was highly significantly associated with higher IQ/DQ. Shorter CSWS duration, but not age, etiology, or previous AED trials, was associated with positive response to steroids. Early discontinuation of the treatment for side effects was encountered in seven patients. We conclude that corticosteroids are safe and efficient for treatment of epilepsy with CSWS. Poor responders are patients with very low IQ and long duration of CSWS.     

妊娠期癫(癎)发作和抗癫(癎)药物对胎儿脑神经元突触素的影响

目的探索妊娠期癫发作和抗癫药对胎儿脑神经元突触素p38(synaptophysin)的影响,以加深对妊娠期癫发作危害胎儿脑发育的认识。方法6月龄引产胎儿分为3组:1组为妊母正常组(6例),2组为妊母应用抗癫药物控制发作组(6例),3组为妊母未应用抗癫药物控制发作组(6例)。运用免疫组化法检测突触素p38在各组胎儿脑部颞叶海马旁回的变化。结果1组免疫组化切片阳性表达产物光密度值(OD)为0.17±0.05,2组为0.16±0.08,3组为0.11±0.07,1、2组阳性表达产物无显著差异(P>0.05),而1、2组分别与3组比较,均有差异(P<0.05),p38在妊母未应用抗癫药物控制发作组胎儿海马旁回中的表达较妊母正常组及妊母应用抗癫药物控制发作组明显减少。结论研究结果表明妊期癫发作对胎儿脑发育的危害比抗癫药物对胎儿的毒性更大。     

Long-term outcome in aqueductal stenosis

In this study, 78 patients with aqueductal stenosis were submitted to detailed neurodevelopmental assessment with a follow-up of 5–25 years. Sixty-eight percent of patients were categorized as normal; they either attended normal school courses or had regular jobs. Among these, 34% had some motor abnormalities (ataxia, mild hemiparesis, visual disturbances). Twenty-four percent (19 cases) were moderately disabled (trainable retardation) and 8% (6 cases) were severely handicapped. Epilepsy was observed in 13% of the cases. Incidence of recurrent and generalized seizures paralleled neurodevelopmental outcome (5% in normal, 16% in moderately disabled and 50% in severely disabled patients). Endocrine dysfunctions were evident in 28% of the cases and were characterized by precocious or delayed puberty, amenorrhea and somatic underdevelopment. No patient with ventricular enlargement and a cortical mantle width below 20 mm showed a good outcome. Large ventricles were compatible with normal mental development when compensated with a corresponding cranial vault enlargement. In patients with normal mental status and motor abnormalities, longterm CT scan findings revealed the presence of focal brain abnormalities (poroencephaly, brain atrophy, calcifications, extracerebral collections).Presented at the Consensus Conference: Hydrocephalus '92, Assisi, Italy, 26–30 Aprill 1992     

Long-term seizure outcome and its predictors in patients with recurrent seizures during the first year aftertemporal lobe resective epilepsy surgery

Purpose: The existing data on the implications of the characteristics of seizures that recur during the first year following epilepsy surgery on subsequent seizure outcome are conflicting. We investigated the impact of recurrent seizures in the first postoperative year and their attributes on long‐term seizure outcome. Methods: We studied the postoperative courses of 492 patients who had completed two or more years of follow‐up after temporal lobe resective epilepsy surgery. We used Kaplan‐Meier survival curves to define long‐term seizure outcome and assessed the predictive value of recurrent seizure characteristics on the outcome by univariate and multivariate proportional hazards regression models. Key Findings: In our patients, seizure recurrences during the first postoperative year, irrespective of the attributes of recurrent seizures (such as provoked vs. unprovoked, and timing and number of recurrences), imparted fourfold to sevenfold increased hazards for continued seizures beyond the first postoperative year. Although patients with complex partial seizures with or without secondary generalized tonic–clonic seizures (CPS/GTCS) had a sixfold increased risk, those with auras alone had only a borderline risk for seizures beyond the first postoperative year. In the multivariate model, CPS/GTCS as the predominant seizure type and three or more seizure recurrences during the first postoperative year independently predicted unfavorable long‐term seizure outcome. Significance: Our study provides valuable information that is helpful in prognosticating and counseling patients, and in making rational decisions on the withdrawal of antiepileptic drugs following surgery. Our findings enhance the general understanding of the etiopathogenesis of surgical failure.