Efficacy of methylphenidate treatment in childhood myotonic dystrophy type 1 and comorbid attention deficit hyperactivity disorder: A case report using eye tracking assessment.

INTRODUCTION: Despite the increased prevalence of comorbid attention deficit hyperactivity disorder (ADHD) in children with myotonic dystrophy type 1, the effects of methylphenidate treatment on associated cognitive deficits in this population is not yet investigated. CASE: We describe a case study of an eleven-year-old male patient with myotonic dystrophy type 1 and comorbid ADHD that was treated with methylphenidate in a twice daily regime (0.60 mg/kg/day). Positive effects on learning and cognition were reported by the parents and teachers. No negative side effects were reported. Sequential neuropsychological assessments before and 45 minutes after methylphenidate intake were conducted to quantify the cognitive effects of methylphenidate treatment. Significant improvements in regulation of attention were behaviorally observed and were quantified using eye tracking technology. CONCLUSION: We conclude that methylphenidate may be an effective treatment for ADHD-related cognitive deficits and learning difficulties in children with myotonic dystrophy type 1 which merits further research.

Fatal perinatal mitochondrial cardiac failure caused by recurrent de novo duplications in the ATAD3 locus.

BACKGROUND: In about half of all patients with a suspected monogenic disease, genomic investigations fail to identify the diagnosis. A contributing factor is the difficulty with repetitive regions of the genome, such as those generated by segmental duplications. The ATAD3 locus is one such region, in which recessive deletions and dominant duplications have recently been reported to cause lethal perinatal mitochondrial diseases characterized by pontocerebellar hypoplasia or cardiomyopathy, respectively. METHODS: Whole exome, whole genome and long-read DNA sequencing techniques combined with studies of RNA and quantitative proteomics were used to investigate 17 subjects from 16 unrelated families with suspected mitochondrial disease. FINDINGS: We report six different de novo duplications in the ATAD3 gene locus causing a distinctive presentation including lethal perinatal cardiomyopathy, persistent hyperlactacidemia, and frequently corneal clouding or cataracts and encephalopathy. The recurrent 68 Kb ATAD3 duplications are identifiable from genome and exome sequencing but usually missed by microarrays. The ATAD3 duplications result in the formation of identical chimeric ATAD3A/ATAD3C proteins, altered ATAD3 complexes and a striking reduction in mitochondrial oxidative phosphorylation complex I and its activity in heart tissue. CONCLUSIONS: ATAD3 duplications appear to act in a dominant-negative manner and the de novo inheritance infers a low recurrence risk for families, unlike most pediatric mitochondrial diseases. More than 350 genes underlie mitochondrial diseases. In our experience the ATAD3 locus is now one of the five most common causes of nuclear-encoded pediatric mitochondrial disease but the repetitive nature of the locus means ATAD3 diagnoses may be frequently missed by current genomic strategies. FUNDING: Australian NHMRC, US Department of Defense, Japanese AMED and JSPS agencies, Australian Genomics Health Alliance and Australian Mito Foundation.

Correction to: Relevance of neuroimaging for neurocognitive and behavioral outcome after pediatric traumatic brain injury.

JC Goslings is the correct name of the sixth author of this article.

The tonic response to the infant knee jerk as an early sign of cerebral palsy.

BACKGROUND: Early identification of infants at risk of cerebral palsy (CP) is desirable in order to provide early intervention. We previously demonstrated differences in knee jerk responses between 3-month-old high risk and typically developing infants. AIMS: To improve early identification by investigating whether the presence of tonic responses (continuous muscle activity occurring after the typical phasic response), clonus or contralateral responses to the knee jerk during infancy is associated with CP. STUDY DESIGN: Longitudinal EMG-study. SUBJECTS: We included 34 high-risk infants (median gestational age 31.9 weeks) who participated in the LEARN2MOVE 0-2 years trial. OUTCOME MEASURES: Video-recorded knee jerk EMG-assessments were performed during infancy (1-4 times). Developmental outcome was assessed at 21 months corrected age (CA). Binomial generalized estimating equations models with repeated measurements were fitted using predictor variables. RESULTS: Infants who later were diagnosed with CP (n = 18) showed more often than infants who were not diagnosed with CP i) tonic responses - from 4 months CA onwards, ii) clonus - from 13 months CA onwards, and iii) contralateral responses - from 15 months CA onwards. LIMITATIONS: The main limitation is the relatively small sample size. CONCLUSIONS: The assessment of tonic responses to the knee jerk using EMG may be a valuable add-on tool to appraise a high risk of CP.

Relevance of neuroimaging for neurocognitive and behavioral outcome after pediatric traumatic brain injury.

This study aims to (1) investigate the neuropathology of mild to severe pediatric TBI and (2) elucidate the predictive value of conventional and innovative neuroimaging for functional outcome. Children aged 8-14 years with trauma control (TC) injury (n = 27) were compared to children with mild TBI and risk factors for complicated TBI (mildRF+, n = 20) or moderate/severe TBI (n = 17) at 2.8 years post-injury. Neuroimaging measures included: acute computed tomography (CT), volumetric analysis on post-acute conventional T1-weighted magnetic resonance imaging (MRI) and post-acute diffusion tensor imaging (DTI, analyzed using tract-based spatial statistics and voxel-wise regression). Functional outcome was measured using Common Data Elements for neurocognitive and behavioral functioning. The results show that intracranial pathology on acute CT-scans was more prevalent after moderate/severe TBI (65%) than after mildRF+ TBI (35%; p = .035), while both groups had decreased white matter volume on conventional MRI (ps ≤ .029, ds ≥ -0.74). The moderate/severe TBI group further showed decreased fractional anisotropy (FA) in a widespread cluster affecting all white matter tracts, in which regional associations with neurocognitive functioning were observed (FSIQ, Digit Span and RAVLT Encoding) that consistently involved the corpus callosum. FA had superior predictive value for functional outcome (i.e. intelligence, attention and working memory, encoding in verbal memory and internalizing problems) relative to acute CT-scanning (i.e. internalizing problems) and conventional MRI (no predictive value). We conclude that children with mildRF+ TBI and moderate/severe TBI are at risk of persistent white matter abnormality. Furthermore, DTI has superior predictive value for neurocognitive out-come relative to conventional neuroimaging.

Sudden falls as a persistent complication of selective dorsal rhizotomy surgery in children with bilateral spasticity: report of 3 cases.

Selective dorsal rhizotomy (SDR) surgery is a well-established treatment for ambulatory children with bilateral spastic paresis and is performed to eliminate spasticity and improve walking. The objective of this case report is to describe sudden falls as a persistent complication of SDR. The authors report on 3 patients with bilateral spastic paresis, aged 12, 6, and 7 years at the time of surgery. The percentage of transected dorsal rootlets was around 40% at the L2-S1 levels. Sudden falls were reported with a frequency of several a day, continuing for years after SDR. The falls were often triggered by performing dual tasks as well as occurring in the transition from sitting to standing, during running, after strenuous exercise, or following a fright. Patients also had residual hyperesthesia and dysesthesia of the foot sole. The authors hypothesize that the sudden falls are caused by a muscle inhibition reflex of the muscles in the legs, as an abnormal reaction to a sensory stimulus that is perceived with increased intensity by a patient with hyperesthesia. A favorable effect of gabapentin medication supports this hypothesis.

Effects of intrathecal baclofen on daily care in children with secondary generalized dystonia: a pilot study.

AIM: Treatment options for dystonic cerebral palsy (CP) are limited. Our aims were to determine whether intrathecal baclofen (ITB) improves daily care, decreases dystonia and decreases pain in patients with dystonic CP. METHODS: Patients received randomized blinded treatment with ITB or placebo. Scores on problems of daily care were recorded and dystonia, pain and comfort were assessed. RESULTS: Four patients (three males, average age 12 years 6 months) were included (all Gross Motor Function Classification System level V). During the trial period problem scores and dystonia scores decreased in all four patients. CONCLUSION: In this pilot study we report positive functional effects of ITB trial treatment in four patients with dystonic CP. A randomized trial with a larger cohort is needed to verify these results.