GNAQ/GNA11 Mosaicism Is Associated with Abnormal Serum Calcium Indices and Microvascular Neurocalcification.

Mosaic mutations in genes GNAQ or GNA11 lead to a spectrum of diseases including Sturge-Weber syndrome and phakomatosis pigmentovascularis with dermal melanocytosis. The pathognomonic finding of localized "tramlining" on plain skull radiography, representing medium-sized neurovascular calcification and associated with postnatal neurological deterioration, led us to study calcium metabolism in a cohort of 42 children. In this study, we find that 74% of patients had at least one abnormal measurement of calcium metabolism, the commonest being moderately low serum ionized calcium (41%) or high parathyroid hormone (17%). Lower levels of ionized calcium even within the normal range were significantly associated with seizures, and with specific antiepileptics despite normal vitamin D levels. Successive measurements documented substantial intrapersonal fluctuation in indices over time, and DEXA scans were normal in patients with hypocalcemia. Neurohistology from epilepsy surgery in five patients revealed not only intravascular, but perivascular and intraparenchymal mineral deposition and intraparenchymal microvascular disease in addition to previously reported findings. Neuroradiology review clearly demonstrated progressive calcium deposition in individuals over time. These findings and those of the adjoining paper suggest that calcium deposition in the brain of patients with GNAQ/GNA11 mosaicism may not be a nonspecific sign of damage as was previously thought, but may instead reflect the central postnatal pathological process in this disease spectrum.

Transient episodes of hemiparesis in Sturge Weber Syndrome - Causes, incidence and recovery.

INTRODUCTION: Sturge Weber Syndrome (SWS) arises from a sporadic condition secondary to a post zygotic mutation in the GNAQ gene, manifested in the majority of cases by capillary malformation of the skin. Children present with seizures, acquired hemiparesis, transient hemiparesis and intellectual disabilities. This project aimed to establish incidence of transient episodes, their recovery time if full recovery was achieved, and events associated with the transient episode. METHODS: This was a retrospective cohort study, approved for clinical audit (Institution number 2182). Children with a diagnosis of SWS seen in a tertiary multidisciplinary clinic from September 2013 to September 2016 were included in the analysis. Data was collated from clinical notes. SPSS 21 was used for analysis. RESULTS: A total of 102 patients had a diagnosed of SWS, the mean age was 10.86 years (range 2-22years). 47/102 participants with SWS had permanent hemiparesis. 32/102 presented with transient episodes. All children with transient hemiparesis had epilepsy. Median recovery time to previous function, following a transient episode was 24 h (range 1 minute-4392 h). All participants fully recovered from the transient episode within a 6 months' time frame. The factors associated with transient episodes were seizures, or a blow to the head. CONCLUSIONS: To our knowledge this is the largest cohort of children with SWS analysed to describe occurrence, association and recovery time of transient hemiparesis. The findings informed service development including change in method to record details of transient episodes. Further information provided to other health professionals will be reviewed.

Autism spectrum disorder, social communication difficulties, and developmental comorbidities in Sturge-Weber syndrome.

Sturge-Weber syndrome (SWS) is a neurocutaneous disorder characterized by the combination of a facial naevus flammeus and pial angioma, often associated with learning difficulties and/or epilepsy. Here, we report on the neuropsychological characteristics of a cohort of 92 children with SWS seen at a national referral center between 2002 and 2015. Almost a quarter (24%) had a diagnosis of autism spectrum disorder (ASD), with 45% overall having evidence of social communication difficulties (SCD). Autism spectrum disorder was more commonly seen in those individuals with bilateral angioma (p = 0.021). Significant behavioral difficulties were reported in 50% while 26% had difficulties with sleep. Difficulties with social communication, behavior, and sleep were closely associated with one another. They were not, however, significantly associated with markers of epilepsy severity and were noted to occur even in children without epilepsy. The prevalence of ASD/SCD, sleep difficulties, and behavioral disorders seen in SWS is high and reflects the complex needs of this group.

Parent- and Teacher-Reported Symptoms of ADHD in School-Aged Children With Active Epilepsy: A Population-Based Study.

OBJECTIVE: Provide data on the distribution of parent- and teacher-reported symptoms of ADHD in childhood epilepsy and describe coexisting cognitive and behavioral disorders in children with both epilepsy and ADHD. METHOD: Eighty-five (74% of those eligible) children (5-15 years) in a population-based sample with active epilepsy underwent psychological assessment. The ADHD Rating Scale-IV (ADHD-RS-IV) scale was completed by parents ( n = 69) and teachers ( n = 67) of participating children with an IQ > 34. ADHD was diagnosed with respect to Diagnostic and Statistical Manual of Mental Disorders (4th ed., text rev.). RESULTS: Parents reported significantly more symptoms of ADHD than teachers ( p < .001). Symptoms of inattention were more commonly reported than symptoms of hyperactivity-impulsivity ( p < .001). Neurobehavioral comorbidity was similar in those with ADHD and non-ADHD with the exception of oppositional defiant disorder (ODD) and developmental coordination disorder (DCD), which were more common in those with both epilepsy and ADHD. CONCLUSION: Symptoms of ADHD are very common in childhood epilepsy but prevalence is influenced by informant.

Symptoms of anxiety and depression in school-aged children with active epilepsy: A population-based study.

METHODS: Children (5-15 years) with active epilepsy were screened using the parent-report (n=69) and self-report (n=48) versions of the Spence Children's Anxiety Scale (SCAS) and the self-report version of the Children's Depression Inventory (CDI) (n=48) in a population-based sample. RESULTS: A total of 32.2% of children (self-report) and 15.2% of children (parent-report) scored ≥1 SD above the mean on the SCAS total score. The subscales where most difficulty were reported on parent-report were Physical Injury and Separation Anxiety. There was less variation on self-report. On the CDI, 20.9% of young people scored ≥1 SD above the mean. Children reported significantly more symptoms of anxiety on the SCAS total score and three of the subscales (p<.05). There was a significant effect on the SCAS total score of respondents by seizure type interaction, suggesting higher scores on SCAS for children with generalized seizures on self- but not parent-report. Higher CDI scores were significantly associated with generalized seizures (p>.05). SUMMARY: Symptoms of anxiety were more common based on self-report compared with parent-report. Children with generalized seizures reported more symptoms of depression and anxiety.

Faulty cardiac repolarization reserve in alternating hemiplegia of childhood broadens the phenotype.

Alternating hemiplegia of childhood is a rare disorder caused by de novo mutations in the ATP1A3 gene, expressed in neurons and cardiomyocytes. As affected individuals may survive into adulthood, we use the term 'alternating hemiplegia'. The disorder is characterized by early-onset, recurrent, often alternating, hemiplegic episodes; seizures and non-paroxysmal neurological features also occur. Dysautonomia may occur during hemiplegia or in isolation. Premature mortality can occur in this patient group and is not fully explained. Preventable cardiorespiratory arrest from underlying cardiac dysrhythmia may be a cause. We analysed ECG recordings of 52 patients with alternating hemiplegia from nine countries: all had whole-exome, whole-genome, or direct Sanger sequencing of ATP1A3. Data on autonomic dysfunction, cardiac symptoms, medication, and family history of cardiac disease or sudden death were collected. All had 12-lead electrocardiogram recordings available for cardiac axis, cardiac interval, repolarization pattern, and J-point analysis. Where available, historical and prolonged single-lead electrocardiogram recordings during electrocardiogram-videotelemetry were analysed. Half the cohort (26/52) had resting 12-lead electrocardiogram abnormalities: 25/26 had repolarization (T wave) abnormalities. These abnormalities were significantly more common in people with alternating hemiplegia than in an age-matched disease control group of 52 people with epilepsy. The average corrected QT interval was significantly shorter in people with alternating hemiplegia than in the disease control group. J wave or J-point changes were seen in six people with alternating hemiplegia. Over half the affected cohort (28/52) had intraventricular conduction delay, or incomplete right bundle branch block, a much higher proportion than in the normal population or disease control cohort (P = 0.0164). Abnormalities in alternating hemiplegia were more common in those ≥16 years old, compared with those <16 (P = 0.0095), even with a specific mutation (p.D801N; P = 0.045). Dynamic, beat-to-beat or electrocardiogram-to-electrocardiogram, changes were noted, suggesting the prevalence of abnormalities was underestimated. Electrocardiogram changes occurred independently of seizures or plegic episodes. Electrocardiogram abnormalities are common in alternating hemiplegia, have characteristics reflecting those of inherited cardiac channelopathies and most likely amount to impaired repolarization reserve. The dynamic electrocardiogram and neurological features point to periodic systemic decompensation in ATP1A3-expressing organs. Cardiac dysfunction may account for some of the unexplained premature mortality of alternating hemiplegia. Systematic cardiac investigation is warranted in alternating hemiplegia of childhood, as cardiac arrhythmic morbidity and mortality are potentially preventable.

Features of developmental coordination disorder in active childhood epilepsy: a population-based study.

AIMS: To provide data on parent-reported features of developmental coordination disorder (DCD) and describe neurobehavioural comorbidity in children with epilepsy and DCD. METHOD: Eighty-five (74% of those eligible) children (44 males, 41 females; age range 5-15y) with active childhood epilepsy (an epileptic seizure in the last year and/or currently taking antiepileptic drugs) in a population-based cohort underwent comprehensive multidisciplinary assessment. The DCD Questionnaire (DCD-Q) was completed by parents (n=69) of children with an IQ>34, of whom 56 did not have cerebral palsy (CP), and were considered for a diagnosis of DCD. RESULTS: Of those considered for a DCD diagnosis, 16 (29%) met DSM-IV-TR criteria whereas 34 (61%) scored in the at-risk range on the DCD-Q. The sensitivity of the DCD-Q was 100% (95% CI 76-100) and specificity was 55% (95% CI 39-70). Significant predictors of higher scores on the DCD-Q included the presence of autism spectrum disorder, CP, and early seizure onset. Increasing age and IQ were independently associated with higher DCD-Q scores. Intellectual disability, attention-deficit-hyperactivity disorder, academic underachievement, and specific memory problems were the most common neurobehavioural difficulties in those with both DCD and epilepsy. INTERPRETATION: Parent-reported symptoms of DCD are very common in childhood epilepsy. The DCD-Q has good sensitivity but lower specificity in this population.

Cognition in school-aged children with "active" epilepsy: A population-based study.

INTRODUCTION: There is a lack of population-based data on specific cognitive profiles in childhood epilepsy. This study sought to determine the frequency of impairments in global cognition and aspects of working memory and processing speed in a population-based sample of children with "active" epilepsy (on antiepileptic Drugs (AEDs), and/or had a seizure in the last year). Factors significantly associated with global and specific difficulties in cognition were also identified. METHOD: A total of 85 (74% of eligible population) school-aged children (5-15 years) with "active" epilepsy underwent comprehensive psychological assessment including assessment of global cognition, working memory, and processing speed. Scores on cognitive subtests were compared via paired-samples t tests. The factors associated with cognitive difficulties were analyzed via linear regression. RESULTS: A total of 24% of children were functioning below IQ 50, and 40% had IQ scores below 70. Scores on the Processing Speed Index were significantly lower than scores on the Verbal or Performance indexes on Wechsler instruments. The Coding subtest was a significant weakness compared with the other Wechsler subtests. A total of 58% of children displayed "memory underachievement" (memory score 1 SD below assessed IQ) on at least one of the four administered working memory subtests. Factors significantly associated with globally impaired cognition included being on polytherapy (ß = -13.0; 95% CI [-19.3, -6.6], p = .000) and having attention-deficit/hyperactivity disorder (ADHD; ß = -11.1, 95% CI [-3.0, -19.3], p = .008). Being on polytherapy was also associated with lower scores on the working memory and processing speed composite scores. Having developmental coordination disorder (DCD) was associated with a lower score on the processing speed composite. CONCLUSIONS: There is a high rate of global and specific cognitive difficulties in childhood epilepsy. Difficulties are most pronounced in aspects of working memory and processing speed. Predictors of cognitive impairment in childhood epilepsy include epilepsy-related and behavioral factors, which may differ depending on the domain of cognition assessed.

Factors associated with quality of life in active childhood epilepsy: a population-based study.

BACKGROUND: Improving health-related quality of life (HRQOL), rather than just reducing seizures, should be the principal goal in comprehensive management of childhood epilepsy. There is a lack of population-based data on predictors of HRQOL in childhood epilepsy. METHODS: The Children with Epilepsy in Sussex Schools (CHESS) study is a prospective, population-based study involving school-aged children (5-15 years) with active epilepsy (on one or more AED and/or had a seizure in the last year) in a defined geographical area in the UK. Eighty-five of 115 (74% of eligible population) children underwent comprehensive psychological assessment including measures of cognition, behaviour, and motor functioning. Parents of the children completed the Quality of Life in Childhood Epilepsy (QOLCE).Clinical data on eligible children was extracted using a standardised pro forma. Linear regression analysis was undertaken to identify factors significantly associated with total Quality of Life in this population. RESULTS: Factors independently significantly associated (p < .05) with total QOLCE scores were seizures before 24 months, cognitive impairment (IQ < 85), anxiety, and parent reported school attendance difficulty. These factors were also significantly associated with total QOLCE when children with IQ < 50 were excluded from analysis. CONCLUSIONS: The majority of factors associated with parent reported HRQOL in active childhood epilepsy are related to neurobehavioural and/or psychosocial aspects of the condition.

Features of autism spectrum disorder (ASD) in childhood epilepsy: a population-based study.

In a defined geographical area in the south of the UK, 115 children with active epilepsy (i.e., children who had seizures in the last year and/or children who were taking antiepileptic drugs (AEDs)) were identified via a computerized database and liaison with local pediatricians. Eighty-five (74%) of the children (5-15years of age) underwent a comprehensive psychological assessment. Twenty-one percent of the children met the DSM-IV-TR criteria for ASD, and 61% of those with ASD had another DSM-IV-TR behavioral or motor disorder. The Autism Spectrum Screening Questionnaire (ASSQ) was completed by parents (n=69) and by teachers (n=67) of children with an IQ>34. Only 9% of children on parent ratings and 15% of children on teacher ratings had no features of ASD. Parents reported significantly (p<.05) more features of ASD on the ASSQ compared with teachers. Factors significantly associated with responses on the ASSQ included respondent (parents reported more features), school placement (more features in specialized settings), and respondent by school placement interaction. Effective screening for ASD in children with epilepsy will need a consideration of the impact of informant and school placement on ratings. In conclusion, features of ASD were common in children with epilepsy regardless of cognitive ability. The ASSQ was a useful screening instrument in this population, and combining parent and teacher forms was optimal in terms of screening properties.

Screening for mental health disorders in active childhood epilepsy: population-based data.

BACKGROUND: Children with epilepsy are at increased risk for behavioral and psychiatric disorders and it has been recommended that all children with epilepsy be screened for such conditions. There is thus a need to identify appropriate screening measures in this population. METHODS: Children with active epilepsy (on AEDs and/or had a seizure in the last year) with an IQ>34 (n=69) were screened for behavioral/psychiatric disorders using the parent and teacher versions of the Strengths and Difficulties Questionnaire (SDQ) in a population-based sample. Consensus clinical diagnoses were made with respect to DSM-IV-TR data. Parent and teacher responses on the SDQ total and subscales were compared using paired samples t-tests and Pearson's correlation. The screening properties of the SDQ were explored. Regression using generalized estimating equations was used to identify predictors of responses on the SDQ. RESULTS: 62% of children received a DSM-IV-TR diagnosis. On the total SDQ score the number of children identified at risk by parents (61%) was higher than the number identified by teachers (43%). Mean parent scores were significantly higher than teacher scores on the SDQ Conduct and Hyperactive subscales and total score after Bonferroni correction (adjusted alpha p<.007). Sensitivity and specificity of the SDQ total score were maximized by combining parent and teacher responses. The positive predictive values (PPVs) were much higher for the total score than the specific subscales suggesting that while the SDQ total score has good predictive ability the specific scales are less useful. Respondent (i.e., parent and teacher) was a significant predictor of scores for some but not all subscales. CONCLUSION: The SDQ can be considered a promising tool for screening children with active epilepsy provided the total score is used as a screener for the presence of any DSM-IV-TR disorder and multi-informant data are used.

Academic achievement in school-aged children with active epilepsy: a population-based study.

OBJECTIVE: To provide population-based data on the performance of school-aged children with epilepsy on measures of academic achievement and factors associated with this performance after controlling for IQ. METHODS: Eighty-five (74%) of 115 children with "active" epilepsy (experienced a seizure in the past year and/or on antiepileptic drugs [AEDs]) underwent psychological assessment including measures of IQ, aspects of working memory and processing speed. Sixty-five of the 85 were able to complete subtests on the Wide Range Achievement Test-Fourth Edition (WRAT-4). Paired sample t-tests were conducted to compare subtest scores. Factors associated with academic performance after controlling for IQ were examined using linear regression. RESULTS: Seventy-two percent of the children, who could complete subtests on the WRAT-4, displayed "low achievement" (1 standard deviation [SD] below test mean) and 42% displayed "underachievement" (1 SD below assessed IQ) on at least one of the four WRAT-4 subtests. The mean scores on the Math Computation subtest and Sentence Comprehension subtest were significantly lower than scores on the Word Reading (p < 0.05) and Spelling (p < 0.001) subtests. Younger age at seizure onset was associated (p < 0.05) with decreased scores on three of the four WRAT-4 subtests after controlling for IQ. Difficulties with auditory working memory were associated with difficulties on reading comprehension (p < 0.05), and parent-reported difficulties with school attendance were associated with decreased scores on the Spelling and Word Reading subtests after controlling for IQ (p < 0.05). SIGNIFICANCE: Difficulties with academic achievement are common in school-aged children with "active" epilepsy. Much of the difficulties can be attributed to lowered global cognition. However, specific cognitive deficits, younger onset of first seizure, and school attendance difficulties may contribute to difficulties independent of global cognition. There is a need to screen all children with "active" epilepsy for difficulties in school achievement, to identify contributory factors and to identify efficacious interventions for ameliorating such difficulties.

Neurobehavioral comorbidities in children with active epilepsy: a population-based study.

BACKGROUND: In addition to recurrent epileptic seizures, children with epilepsy can have coexisting cognitive and behavioral difficulties but the spectrum and prevalence of such difficulties are uncertain. METHODS: The Children with Epilepsy in Sussex Schools study is a prospective, community-based study involving school-aged children (5­15 years) with active epilepsy in a defined geographical area in the United Kingdom. Participants underwent comprehensive psychological assessment, including measures of cognition, behavior, and motor functioning. Consensus neurobehavioral diagnoses were made with respect to Diagnostic and Statistical Manual, Fourth Edition-Text Revision (DSM-IV-TR) criteria. RESULTS: A total of 85 children (74% of eligible population) were enrolled; 80% of children with active epilepsy had a DSM-IV-TR behavioral disorder and/or cognitive impairment (IQ ,85). Intellectual disability (ID) (IQ ,70) (40%), attention-deficit/hyperactivity disorder (ADHD) (33%), and autism spectrum disorder (ASD) (21%) were the most common neurobehavioral diagnoses. Of those who met criteria for a DSM-IV-TR behavioral disorder, only one-third had previously been diagnosed. Logistic regression revealed that seizures in the first 24 months compared with first seizures at 24 to 60 or 61+ months (odds ratio [OR] 13, 95% confidence interval 2.2­76.9; OR 21.3, 3.2­148.9) and polytherapy (OR 7.7, 1.6­36.3) were independently associated with ID and the presence of ID was associated with a diagnosis of ASD (OR 14.1, 2.3­87.1) after Bonferroni adjustment. Epilepsy-related factors did not independently predict the presence of behavioral disorders. CONCLUSIONS: Screening for neurobehavioral comorbidities should be an integral part of management in children with "active" epilepsy. There is a need for research to identify neurobiological mechanisms underpinning neurobehavioral impairments and studies to evaluate possible treatments.

Arterial spin labeling characterization of cerebral perfusion during normal maturation from late childhood into adulthood: normal 'reference range' values and their use in clinical studies.

The human brain changes structurally and functionally during adolescence, with associated alterations in cerebral perfusion. We performed dynamic arterial spin labeling (ASL) magnetic resonance imaging in healthy subjects between 8 and 32 years of age, to investigate changes in cerebral hemodynamics during normal development. In addition, an inversion recovery sequence allowed quantification of changes in longitudinal relaxation time (T1) and equilibrium longitudinal magnetization (M0). We present mean and reference ranges for normal values of T1, M0, cerebral blood flow (CBF), bolus arrival time, and bolus duration in cortical gray matter, to provide a tool for identifying age-matched perfusion abnormalities in this age range in clinical studies. Cerebral blood flow and T1 relaxation times were negatively correlated with age, without gender or hemisphere differences. The same was true for M0 anteriorly, but posteriorly, males but not females showed a significant decline in M0 with increasing age. Two examples of the clinical utility of these data in identifying age-matched perfusion abnormalities, in Sturge-Weber syndrome and sickle cell anemia, are illustrated.

Methylphenidate treatment of attention deficit hyperactivity disorder in young people with learning disability and difficult-to-treat epilepsy: evidence of clinical benefit.

PURPOSE: To establish the efficacy and safety of methylphenidate (MPH) treatment for attention deficit hyperactivity disorder (ADHD) in a group of children and young people with learning disability and severe epilepsy. METHODS: This retrospective study systematically reviewed the case notes of all patients treated with methylphenidate (MPH) for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) ADHD at a specialist epilepsy center between 1998 and 2005. Treatment efficacy was ascertained using clinical global impressions (CGI) scores, and safety was indexed by instances of >25% increase in monthly seizure count within 3 months of starting MPH. KEY FINDINGS: Eighteen (18) patients were identified with refractory epilepsies (14 generalized, 4 focal), IQ <70, and ADHD. Male patients predominated (13:5) and ADHD was diagnosed at a median age of 11.5 years (range 6­18 years). With use of a combination of a behavioral management program and MPH 0.3­1 mg/kg/day, ADHD symptoms improved in 61% of patients (11/18; type A intraclass correlation coefficient of CGI 0.85, 95% confidence interval [CI] 0.69­0.94). Daily MPH dose, epilepsy variables, and psychiatric comorbidity did not relate to treatment response across the sample. MPH adverse effects led to treatment cessation in three patients (dysphoria in two, anxiety in one). There was no statistical evidence for a deterioration of seizure control in this group with the use of MPH. SIGNIFICANCE: Methylphenidate with behavioral management was associated with benefit in the management of ADHD in more than half of a group of children with severe epilepsy and additional cognitive impairments. Eighteen percent had significant side effects but no attributable increase in seizures. Methylphenidate is useful in this group and is likely to be under employed.

Development and validation of a measure of the impact of epilepsy on a young person's quality of life: Glasgow epilepsy outcome scale for young persons (GEOS-YP).

OBJECTIVE: The goal of the work described here was to develop and validate a measure of the impact of epilepsy on an adolescent's quality of life that is based on direct exploration of the adolescent's views. METHODS: Initial scale development was based on data generated through qualitative methods (focus groups) in a previous study [McEwan MJ, Espie CA, Metcalfe J, Brodie MJ, Wilson MT. Seizure 2004;13:15-31]. A draft measure was piloted (n=30) and refined using correlational methods. Psychometric properties were established by means of a preliminary field trial (n=78). RESULTS: An initial item pool of 76 was refined to 50. The structure of the measure mirrored the conceptual model derived from focus group study; Part 1 covered issues relating to adolescent development (identity formation) with five subscales, and Part 2 covered epilepsy-related issues with four subscales. The final GEOS-YP had good internal consistency (alpha=0.91) and test-retest reliability (rho=0.75). Concurrent and construct validity was acceptable, and the GEOS-YP discriminated on dimensions of clinical importance. Participant feedback suggested the measure has excellent face validity and potential clinical utility. CONCLUSIONS: The GEOS-YP is a direct measure of how adolescents perceive epilepsy impacts their quality of life. The GEOS-YP has sound psychometric properties and provides a relatively brief and potentially useful clinical outcome tool.

Pyridoxine-dependent seizures: a family phenotype that leads to severe cognitive deficits, regardless of treatment regime.

The neuropsychological and clinical histories of three male siblings affected by pyridoxine-dependent seizures with known homozygous antiquitin mutations are presented. Neuropsychological evaluation is reported from when the siblings were 11, 9, and 7 years of age. Two of the siblings had received early pyridoxine treatment (antenatal, 2-4 wks into pregnancy) and one had received late treatment (2mo postnatal). However, there was no differential effect on cognitive outcome, with all three siblings having moderate to severe learning disability. Unlike previously reported cases that received early postnatal treatment, none of the siblings had relatively preserved non-verbal cognitive skills. Equally, their intellectual performance over time did not increase above the 1st centile despite high maintenance doses of vitamin B6 (range 16-26 mg/kg/d), and mild sensory neuropathy was reported on nerve conduction studies. The findings in these siblings challenge assumptions that early and high dose pyridoxine treatment can benefit cognition in this population and suggest routine electromyography monitoring may be beneficial.

Eye rolling as a manifestation of clobazam toxicity in a child with epilepsy.

A four-year-old male with symptomatic generalized epilepsy presented with ataxia, eye rolling, and episodes of back arching which were of non-epileptic origin following the introduction of clobazam at 0.75mg/kg/day. Concurrent antiepileptic medication was lamotrigine at 13mg/kg/day. Clobazam plasma levels were within the normal range, while N-desmethylclobazam (DCLB) concentrations were between five and seven times above the upper limit of the normal range. The plasma elimination half-life for DCLB was prolonged, suggesting a genetic variability in DCLB metabolism leading to toxicity. Reduction in the dose of clobazam to 0.3mg/kg/day was associated with resolution of the non-epileptic neurological symptoms, reduction in DCLB plasma levels, and maintenance of seizure control.

Central osteosclerosis with trichothiodystrophy.

Trichothiodystrophy (TTD) is a rare, autosomal recessive, multisystem disorder associated with defects in nucleotide excision repair. We report a 7-year-old boy with TTD due to mutation in the XPD gene. The patient has classic features of this condition, including brittle, sulphur-deficient hair, ichthyosis, growth retardation and developmental delay. In addition, he has radiological evidence of progressive central osteosclerosis. Although similar radiological findings have previously been reported in a small number of patients, this association is not widely recognised. We review the radiological findings in this and other similar cases and discuss the natural history of these bony changes.