Peter Uldall

De novo mutations in ATP1A3 cause alternating hemiplegia of childhood

Alternating hemiplegia of childhood (AHC) is a rare, severe neurodevelopmental syndrome characterized by recurrent hemiplegic episodes and distinct neurological manifestations. AHC is usually a sporadic disorder and has unknown etiology. We used exome sequencing of seven patients with AHC and their unaffected parents to identify de novo nonsynonymous mutations in ATP1A3 in all seven individuals. In a subsequent sequence analysis of ATP1A3 in 98 other patients with AHC, we found that ATP1A3 mutations were likely to be responsible for at least 74% of the cases; we also identified one inherited mutation in a case of familial AHC. Notably, most AHC cases are caused by one of seven recurrent ATP1A3 mutations, one of which was observed in 36 patients. Unlike ATP1A3 mutations that cause rapid-onset dystonia-parkinsonism, AHC-causing mutations in this gene caused consistent reductions in ATPase activity without affecting the level of protein expression. This work identifies de novo ATP1A3 mutations as the primary cause of AHC and offers insight into disease pathophysiology by expanding the spectrum of phenotypes associated with mutations in ATP1A3.

Lamotrigine plasma levels reduced by oral contraceptives

Although it is known that the use of oral contraceptives (OCs) can induce glucuronide conjugating enzymes, currently no data exists as to the potential that the elimination of the glucuronidated drug lamotrigine (LTG) is increased by OCs. We present seven cases in whom the plasma levels of LTG were significantly decreased by OCs (mean 49%, range 41-64%). The interaction was of clinical relevance in most of the patients who either experienced increased seizure frequency/recurrence of seizures after OCs had been added, or adverse effects following withdrawal of OCs.

Infection-Triggered Familial or Recurrent Cases of Acute Necrotizing Encephalopathy Caused by Mutations in a Component of the Nuclear Pore, RANBP2

Acute necrotizing encephalopathy (ANE) is a rapidly progressive encephalopathy that can occur in otherwise healthy children after common viral infections such as influenza and parainfluenza. Most ANE is sporadic and nonrecurrent (isolated ANE). However, we identified a 7 Mb interval containing a susceptibility locus (ANE1) in a family segregating recurrent ANE as an incompletely penetrant, autosomal-dominant trait. We now report that all affected individuals and obligate carriers in this family are heterozygous for a missense mutation (c.1880C-->T, p.Thr585Met) in the gene encoding the nuclear pore protein Ran Binding Protein 2 (RANBP2). To determine whether this mutation is the susceptibility allele, we screened controls and other patients with ANE who are unrelated to the index family. Patients from 9 of 15 additional kindreds with familial or recurrent ANE had the identical mutation. It arose de novo in two families and independently in several other families. Two other patients with familial ANE had different RANBP2 missense mutations that altered conserved residues. None of the three RANBP2 missense mutations were found in 19 patients with isolated ANE or in unaffected controls. We conclude that missense mutations in RANBP2 are susceptibility alleles for familial and recurrent cases of ANE.

Probability of Walking in Children With Cerebral Palsy in Europe

OBJECTIVES. The purpose of this work was to describe walking ability in children with cerebral palsy from the Surveillance of Cerebral Palsy in Europe common database through 21 years and to examine the association between walking ability and predicting factors. PATIENTS AND METHODS. Anonymous data on 10042 children with cerebral palsy born between 1976 and 1996 were gathered from 14 European centers; 9012 patients were eligible for the analyses. RESULTS. Unaided walking as the primary way of walking at 5 years of age was reported for 54%, walking with assistive devices was reported for 16%, and no walking ability was reported for 30%. The proportion of children who were unable to walk was rather stable over time in all of the centers, with a mean proportion of 28%. Walking ability related significantly to cerebral palsy types, that is, spastic unilateral, spastic bilateral, dyskinetic, and ataxic cerebral palsy, as well as to IQ level, active epilepsy, and severe visual and hearing impairment. Severe cerebral palsy, defined as both the inability to walk and an IQ of <50, was present in 20% of the subjects. Logistic regression revealed that intellectual capacity was the variable most associated with walking ability in all 4 of the cerebral palsy types. The presence of a severe intellectual impairment increased the risk of being unable to walk 56 times if the child had unilateral spastic cerebral palsy type and 9 times if the child had bilateral spastic cerebral palsy type. CONCLUSIONS. The collaboration Surveillance of Cerebral Palsy in Europe provides a powerful means of monitoring trends in cerebral palsy and its functional consequences. The proportion of nonwalking in children with cerebral palsy seems to be rather stable over years and across centers despite the changes that have occurred in neonatal care across Europe. As is well known and also shown in this study, walking ability varied strongly with cerebral palsy type. Additional impairments, as well as the presence of epilepsy, correlated significantly with walking ability and, thus, the walking ability can be an indicator of total disability load.

Frequency of participation of 8-12-year-old children with cerebral palsy: A multi-centre cross-sectional European study

Participation in home, school and community is important for all children; and little is known about the frequency of participation of disabled children. Frequency of participation is a valuable outcome measure for evaluating habilitation programmes for disabled children and for planning social and health services. We investigated how frequency of participation varied between children with cerebral palsy and the general population; and examined variation across countries to understand better how the environmental factors such as legislation, public attitudes and regulation in different countries might influence participation. We undertook a multi-centre, population-based study in children with and without cerebral palsy. Working from the Life-H instrument, we developed a questionnaire to capture frequency of participation in 8-12-year-old children. In nine regions of seven European countries, parents of 813 children with cerebral palsy and 2939 children from the general populations completed the questionnaire. Frequency of participation for each question was dichotomised about the median; multivariable logistic regressions were carried out. In the general population, frequency of participation varied between countries. Children with cerebral palsy participated less frequently in many but not all areas of everyday life, compared with children from the general population. There was regional variation in the domains with reduced participation and in the magnitude of the differences. We discuss how this regional variation might be explained by the different environments in which children live. Attending a special school or class was not associated with further reduction in participation in most areas of everyday life.

Attentional and executive impairments in children with spastic cerebral palsy

Aim  Children with cerebral palsy (CP) are reported to have learning and social problems. The aim of the present study was to examine whether children with CP have impairments in attention or executive function.

Education and employment prospects in cerebral palsy

Parents and paediatric neurologists need information on the long‐term social prognosis of children with cerebral palsy (CP). No large population‐based study has been performed on this topic. On 31 December 1999, to find predictors in childhood of subsequent education and employment, 819 participants with CP born between 1965 and 1978 (471 males; mean age 28y 10mo, SD 4y, range 21 to 35y) in the Danish Cerebral Palsy Registry were compared with 4406 controls without CP born between 1965 and 1978 (2546 males; mean age 28y 10mo, SD 4y, range 21 to 35y). Diagnostic subtypes of the 819 participants with CP were: 31% hemiplegia, 43% diplegia, 18% tetraplegia, and 8% other types. Level of motor impairment with respect to walking ability was: 62% able to walk without assistance, 21% with assistance, and 16% not able to walk (for 1% of study children walking ability was not known). Relevant information was obtained from Denmarks unique registries. Of the participants with CP, 33% vs 77% of controls, had education beyond lower secondary school (i.e. after age 15‐16y), 29% were competitively employed (vs 82% of controls), 5% were studying, and 5% had specially created jobs. Excluding participants with CP with an estimated developmental quotient (DQ) of less than 50 or inability to walk at age 5 to 6 years, the odds ratios (multivariate analysis) for not being competitively employed were 1.9 for diplegia versus hemiplegia, 22.5 for DQ 50 to 85 versus DQ greater than 85, and 3.7 for those with epilepsy versus those without epilepsy. The severity of motor impairment among participants with CP able to walk had just a minor influence. Only half the participants with CP who had attended mainstream schooling were employed. In conclusion several childhood characteristics seemed to predict long‐term social prognosis.

Lifetime costs of cerebral palsy

This study quantified the lifetime costs of cerebral palsy (CP) in a register‐based setting. It was the first study outside the US to assess the lifetime costs of CP. The lifetime costs attributable to CP were divided into three categories: health care costs, productivity costs, and social costs. The population analysed was retrieved from the Danish Cerebral Palsy Register, which covers the eastern part of the country and has registered about half of the Danish population of individuals with CP since 1950. For this study we analysed 2367 individuals with CP, who were born in 1930 to 2000 and were alive in 2000. The prevalence of CP in eastern Denmark was approximately 1.7 per 1000. Information on productivity and the use of health care was retrieved from registers. The lifetime cost of CP was about €860 000 for men and about €800 000 for women. The largest component was social care costs, particularly during childhood. A sensitivity analysis found that alterations in social care costs had a small effect, whereas lowering the discount rate from 5 to 3 per cent markedly increased total lifetime costs. Discounting decreases the value of costs in the future compared with the present. The high social care costs and productivity costs associated with CP point to a potential gain from labour market interventions that benefit individuals with CP.

Transcranial direct current stimulation in refractory continuous spikes and waves during slow sleep: A controlled study

Cathodal transcranial direct current stimulation (tDCS) decreases cortical excitability. The purpose of the study was to investigate whether cathodal tDCS could interrupt the continuous epileptiform activity. Five patients with focal, refractory continuous spikes and waves during slow sleep were recruited. Cathodal tDCS and sham stimulation were applied to the epileptic focus, before sleep (1 mA; 20 min). Cathodal tDCS did not reduce the spike-index in any of the patients.

STXBP1 encephalopathy A neurodevelopmental disorder including epilepsy

Objective: To give a comprehensive overview of the phenotypic and genetic spectrum of STXBP1 encephalopathy (STXBP1-E) by systematically reviewing newly diagnosed and previously reported patients. Methods: We recruited newly diagnosed patients with STXBP1 mutations through an international network of clinicians and geneticists. Furthermore, we performed a systematic literature search to review the phenotypes of all previously reported patients. Results: We describe the phenotypic features of 147 patients with STXBP1-E including 45 previously unreported patients with 33 novel STXBP1 mutations. All patients have intellectual disability (ID), which is mostly severe to profound (88%). Ninety-five percent of patients have epilepsy. While one-third of patients presented with Ohtahara syndrome (21%) or West syndrome (9.5%), the majority has a nonsyndromic early-onset epilepsy and encephalopathy (53%) with epileptic spasms or tonic seizures as main seizure type. We found no correlation between severity of seizures and severity of ID or between mutation type and seizure characteristics or cognitive outcome. Neurologic comorbidities including autistic features and movement disorders are frequent. We also report 2 previously unreported adult patients with prominent extrapyramidal features. Conclusion: De novo STXBP1 mutations are among the most frequent causes of epilepsy and encephalopathy. Most patients have severe to profound ID with little correlation among seizure onset, seizure severity, and the degree of ID. Accordingly, we hypothesize that seizure severity and ID present 2 independent dimensions of the STXBP1-E phenotype. STXBP1-E may be conceptualized as a complex neurodevelopmental disorder rather than a primary epileptic encephalopathy.