Body composition and motor function in children born large for gestational age at term.

BACKGROUND: This cross-sectional study compared body composition and motor function between children who were born large for gestational age (LGA) and those born appropriate for gestational age (AGA) and to investigate the association between gait quality and other variables. METHODS: Body composition was determined using a bioelectrical impedance analyzer. Motor functions were assessed using one-leg standing time, timed up-and-go test, five times sit-to-stand test, and three-dimensional gait analysis. We compared the results between two groups. We performed multiple regression analysis to evaluate the association between gait deviation index and variables of LGA, fat mass index, and motor functions (adjusted for age and sex). RESULTS: Children aged 6-12 years who were born LGA at term (n = 23) and those who were born AGA at term (n = 147) were enrolled. The LGA group had a higher fat mass index (2.9 vs. 2.2, p = 0.006) and lower gait deviation index (91.4 vs. 95.4, p = 0.011) than the AGA group. On multiple regression analysis, gait deviation index was associated with being LGA and fat mass index. CONCLUSIONS: In school-aged children who were born LGA, monitoring increased fat mass index and decreased gait deviation index could lessen the risk of metabolic syndrome and reduced gait function. IMPACT: Children aged 6-12 years who were born large for gestational age (LGA) at term showed a higher fat mass index and lower gait deviation index than those who were born appropriate for gestational age at term. No significant differences in balance function or muscle strength were observed between groups. On multiple regression analysis, gait deviation index was associated with being LGA at birth and fat mass index. In school-aged children who were born LGA, monitoring increased fat mass index and decreased gait deviation index could lessen the risk of metabolic syndrome and reduced gait function.

Underlying Disorders in Children With Infection-Related Acute Encephalopathy.

BACKGROUND: Various factors contribute to the development of infection-related acute encephalopathy (AE) in children, such as infectious agents and chronic underlying disorders. We studied underlying disorders in children with AE to identify predisposing factors of AE. METHODS: We investigated underlying disorders or past histories in patients with two types of AE from the database in the Tokai area of Japan between 2009 and 2022: 204 patients with AE with reduced subcortical diffusion (AED) and 137 with clinically mild encephalopathy with a reversible splenial lesion (MERS). We compared them with 89 patients with acute disseminated encephalomyelitis (ADEM) to clarify the specific disorders in the two AE types. RESULTS: The prevalence of underlying disorders in AED (34%, 70 patients) was significantly higher than that in ADEM (12%, 11 patients) (P < 0.01). The prevalence of underlying disorders in MERS was 23% (32 patients). The underlying disorders included seizure disorders, premature birth, genetic/congenital disorders, and endocrine/renal diseases. In patients with seizure disorders in AED, five patients (18%) had Dravet syndrome and four (15%) had West syndrome, whereas none with MERS had these syndromes. Twenty-five (12%) of 204 patients with AED, three (2%) with MERS, and one (1%) with ADEM were preterm or low birth weight. CONCLUSIONS: The high prevalence of seizure disorders suggests that seizure susceptibility is an important predisposing factor in AED. Premature birth also has an impact on the development of AED. Caution is required regarding the development of AE in patients with chronic seizure disorders or premature birth.

Three-Dimensional Gait Analysis as a Biomarker for GTP Cyclohydrolase 1-Deficient Dopa-Responsive Dystonia.

BACKGROUND: GTP-cyclohydrolase 1-deficient dopa-responsive dystonia (GTPCH1-deficient DRD) typically presents in childhood with dystonic posture of the lower extremities, gait impairment, and a significant response to levodopa. We performed three-dimensional gait analysis (3DGA) to quantitatively assess the gait characteristics and changes associated with levodopa treatment in patients with GTPCH1-deficient DRD. METHODS: Three levodopa-treated patients with GTPCH1-deficient DRD underwent 3DGA twice, longitudinally. Changes were evaluated for cadence; gait speed; step length; gait deviation index; kinematic data of the pelvis, hip, knee, and ankle joints; and foot progression angle. RESULTS: Levodopa treatment increased the cadence and gait speed in one of three patients and increased the gait deviation index in two of three patients. The kinematic data for each joint exhibited different characteristics, with some improvement observed in each of the three patients. There was consistent marked improvement in the abnormal foot progression angle; one patient had excessive external rotation of one foot, another had excessive bilateral internal rotation, and the other had excessive internal rotation of one foot and excessive external rotation of the opposite foot, all of which improved. CONCLUSION: The 3DGA findings demonstrate that the gait pathology and recovery process in GTPCH1-deficient DRD vary from case to case. Changes in the foot progression angle and gait deviation index can enable the effects of treatment to be more easily evaluated.

Effect of levodopa on pathological gait in Dravet syndrome: A randomized crossover trial using three-dimensional gait analysis.

OBJECTIVE: Individuals with Dravet syndrome (DS) exhibit progressive gait disturbance. No quantitative studies have been conducted to evaluate the effectiveness of medication for gait disturbance. Therefore, the aim of this study was to evaluate the effectiveness of levodopa for pathological gait in people with DS using three-dimensional gait analysis (3DGA). METHODS: Nine individuals with DS, ages 6-20 years, participated in a crossover study of levodopa and were randomly assigned to the levodopa precedence or no levodopa precedence group. Levodopa/carbidopa hydrate was prescribed at a dose of 5 mg/kg/day (body weight <60 kg) or 300 mg/day (body weight ≥60 kg). The medication was taken for 4-6 weeks (4-week washout period). 3DGA was performed three times before the study, with and without levodopa. A mixed-effects model was used to evaluate the effectiveness of levodopa. The primary outcome was the change in the Gait Deviation Index (GDI). In addition, spatiotemporal gait parameters, 6-minute walking distance (6MD), and balance were evaluated. The correlation between the effectiveness of levodopa and age or gait performance before starting levodopa was analyzed. RESULTS: Levodopa improved the GDI by 4.2 points, (p = .029), 6MD by 52 m (p = .002), and balance test result by 4.1 mm (p = .011) in participants with DS. No severe adverse events were observed, with the exception of one participant, who exhibited fever and consequently stopped taking levodopa. Levodopa was more effective in younger participants with a higher baseline gait performance. SIGNIFICANCE: Our randomized crossover trial showed that levodopa has the potential to improve gait disturbance in people with DS.

Intrauterine exposure to chorioamnionitis and neuroanatomical alterations at term-equivalent age in preterm infants.

PURPOSE: Infants born to mothers with chorioamnionitis (CAM) are at increased risk of developing adverse neurodevelopmental disorders in later life. However, clinical magnetic resonance imaging (MRI) studies examining brain injuries and neuroanatomical alterations attributed to CAM have yielded inconsistent results. We aimed to determine whether exposure to histological CAM in utero leads to brain injuries and alterations in the neuroanatomy of preterm infants using 3.0- Tesla MRI at term-equivalent age. METHODS: A total of 58 preterm infants born before 34 weeks of gestation at Nagoya University Hospital between 2010 and 2018 were eligible for this study (CAM group, n = 21; non-CAM group, n = 37). Brain injuries and abnormalities were assessed using the Kidokoro Global Brain Abnormality Scoring system. Gray matter, white matter, and subcortical gray matter (thalamus, caudate nucleus, putamen, pallidum, hippocampus, amygdala, and nucleus accumbens) volumes were evaluated using segmentation tools (SPM12 and Infant FreeSurfer). RESULTS: The Kidokoro scores for each category and severity in the CAM group were comparable to those observed in the non-CAM group. White matter volume was significantly smaller in the CAM group after adjusting for covariates (postmenstrual age at MRI, infant sex, and gestational age) (p = 0.007), whereas gray matter volume was not significantly different. Multiple linear regression analyses revealed significantly smaller volumes in the bilateral pallidums (right, p = 0.045; left, p = 0.038) and nucleus accumbens (right, p = 0.030; left, p = 0.004) after adjusting for covariates. CONCLUSIONS: Preterm infants born to mothers with histological CAM showed smaller volumes in white matter, pallidum, and nucleus accumbens at term-equivalent age.

Medical records as screening tools for child death review in Japan.

BACKGROUND: Although many child death review (CDR) systems have been developed in Japan, the optimal system is still being identified. The aim of this study is to identify the etiologies of child deaths and to propose a screening method for initiating the CDR process in Japan. METHODS: Clinical medical records (CMRs) in hospitals and autopsy records were surveyed for cases of deaths of children aged less than 15 years between 2014 and 2016 in Aichi Prefecture, Japan. The data were analyzed in three steps, and the findings were compared with the vital statistics. RESULTS: Of the 695 children whose death certificates were submitted to Aichi Prefecture, 590 could be traced to pediatric care hospitals. The distribution of causes of death was slightly different from the vital statistics, with 11.5% dying of extrinsic causes and 19.7% dying of unknown causes. Maltreatment was suspected in 64 cases, which was much higher than that in government statistics. Overall, 158 (26.8%) deaths were considered preventable. The number of unnatural deaths, which might be screened in, was calculated as 172 (29.2%) in the vital statistics, whereas the survey of CMRs revealed that 241 (40.8%) to 282 (47.8%) should be screened in. CONCLUSIONS: Surveying CMRs in hospitals may be a suitable method to detect and screen deaths to start the CDR process in Japan.

A Brain Morphometry Study with Across-Site Harmonization Using a ComBat-Generalized Additive Model in Children and Adolescents.

Regional anatomical structures of the brain are intimately connected to functions corresponding to specific regions and the temporospatial pattern of genetic expression and their functions from the fetal period to old age. Therefore, quantitative brain morphometry has often been employed in neuroscience investigations, while controlling for the scanner effect of the scanner is a critical issue for ensuring accuracy in brain morphometric studies of rare orphan diseases due to the lack of normal reference values available for multicenter studies. This study aimed to provide across-site normal reference values of global and regional brain volumes for each sex and age group in children and adolescents. We collected magnetic resonance imaging (MRI) examinations of 846 neurotypical participants aged 6.0-17.9 years (339 male and 507 female participants) from 5 institutions comprising healthy volunteers or neurotypical patients without neurological disorders, neuropsychological disorders, or epilepsy. Regional-based analysis using the CIVET 2.1.0. pipeline provided regional brain volumes, and the measurements were across-site combined using ComBat-GAM harmonization. The normal reference values of global and regional brain volumes and lateral indices in our study could be helpful for evaluating the characteristics of the brain morphology of each individual in a clinical setting and investigating the brain morphology of ultra-rare diseases.

Connectivity alteration in thalamic nuclei and default mode network-related area in memory processes in mesial temporal lobe epilepsy using magnetoencephalography.

This work aimed to investigate the involvement of the thalamic nuclei in mesial temporal lobe epilepsy (MTLE) and identify the influence of interictal epileptic discharges on the neural basis of memory processing by evaluating the functional connectivity (FC) between the thalamic nuclei and default mode network-related area (DMNRA) using magnetoencephalography. Preoperative datasets of nine patients with MTLE with seizure-free status after surgery and those of nine healthy controls were analyzed. The FC between the thalamic nuclei (anterior nucleus [ANT], mediodorsal nucleus [MD], intralaminar nuclei [IL]), hippocampus, and DMNRA was examined for each of the resting, pre-spike, spike, and post-spike periods in the delta to ripple bands using magnetoencephalography. The FC between the ANT, MD, hippocampus, and medial prefrontal cortex increased in the gamma to ripple bands, whereas the FC between the ANT, IL, and DMNRA decreased in the delta to beta bands, compared with that of the healthy controls at rest. Compared with the rest period, the pre-spike period had significantly decreased FC between the ANT, MD, and DMNRA in the ripple band. Different FC changes between the thalamic nuclei, hippocampus, and DMNRA of specific connections in a particular band may reflect impairment or compensation in the memory processes.

Two Cases of Juvenile Myelomonocytic Leukemia and Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease.

BACKGROUND: Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is an autoimmune demyelinating disorder that often manifests after infections or vaccinations. We report two patients who developed MOGAD out of eight patients with juvenile myelomonocytic leukemia (JMML) that has never been reported. METHODS: We investigated two patients with JMML who developed MOGAD among 127 patients with leukemia from 2012 to 2021. RESULTS: Patient 1 was treated for JMML and developed fever and impaired consciousness at two years and one month of age. Magnetic resonance imaging revealed high-intensity lesions in the left frontal and left occipital white matter. The serum anti-MOG antibody test was positive, while the test was negative in the stored serum 45 days before the onset of encephalopathy. He had relapse of MOGAD after steroid therapy and plasmapheresis. Patient 2, who was treated for JMML, became apathetic and mute at three years and seven months of age. Magnetic resonance imaging revealed left frontoparietal subcortical high-intensity lesions. Anti-MOG antibody at the onset of encephalopathy was positive, while it was negative in stored serum 57 days before and 47 days after the onset. CONCLUSION: We treated two patients who developed MOGAD out of eight patients with JMML and none with MOGAD out of 119 patients with acute lymphocytic leukemia, acute myelocytic leukemia, or chronic myelocytic leukemia. The activated autoimmune process via the RAS pathway abnormality may have led to the formation of the anti-MOG antibody and the onset of MOGAD. MOGAD can occur in children with JMML, and abnormalities of the RAS pathway possibly contribute to its onset.

Association between cerebrospinal fluid parameters and developmental and neurological status in glucose transporter 1 deficiency syndrome.

OBJECTIVE: In glucose transporter 1 deficiency syndrome (Glut1DS), cerebrospinal fluid glucose (CSFG) and CSFG to blood glucose ratio (CBGR) show significant differences among groups classified by phenotype or genotype. The purpose of this study was to investigate the association between these biochemical parameters and Glut1DS severity. METHODS: The medical records of 45 patients who visited Osaka University Hospital between March 2004 and December 2021 were retrospectively examined. Neurological status was determined using the developmental quotient (DQ), assessed using the Kyoto Scale of Psychological Development 2001, and the Scale for the Assessment and Rating of Ataxia (SARA). CSF parameters included CSFG, CBGR, and CSF lactate (CSFL). RESULTS: CSF was collected from 41 patients, and DQ and SARA were assessed in 24 and 27 patients, respectively. Simple regression analysis showed moderate associations between neurological status and biochemical parameters. CSFG resulted in a higher R2 than CBGR in these analyses. CSF parameters acquired during the first year of life were not comparable to those acquired later. CSFL was measured in 16 patients (DQ and SARA in 11 and 14 patients, respectively). Although simple regression analysis also showed moderate associations between neurological status and CSFG and CSFL, the multiple regression analysis for DQ and SARA resulted in strong associations through the use of a combination of CSFG and CSFL as explanatory variables. CONCLUSION: The severity of Glut1DS can be predicted from CSF parameters. Glucose and lactate are independent contributors to the developmental and neurological status in Glut1DS.

Decreased walking efficiency in elementary school children with developmental coordination disorder trait.

OBJECTIVE: To compare walking efficiency, and associated physical function, between children, with and without developmental coordination disorder trait. DESIGN: Cross-sectional study. SETTING: The study was conducted in a Medical and Rehabilitation Center for Developmental Disabilities in Okazaki, Japan. SUBJECTS: The study included 286 children, 6-12 years of age, with and without developmental coordination disorder trait. Developmental coordination disorder trait was defined by a score below the -1 standard deviation on the Japanese version of the Developmental Coordination Disorder Questionnaire. Based on this criterion, 45 children (28 boys) were classified into the developmental coordination disorder trait group and the other 241 (115 boys) in the control group. MEASURES: The following physical function outcomes were measured: single leg stance test; step length variability; and walking efficiency, measured using the 2-min walk test. Logistic regression analysis was used to determine the association between developmental coordination disorder trait and lower walking efficiency and physical function. RESULTS: Compared to the control group, the developmental coordination disorder group showed lower walking efficiency (P = 0.026), higher step length variability (P = 0.047), and shorter single leg stance test (P = 0.001). Developmental coordination disorder was independently associated with walking efficiency (odds ratio, 1.03; 95% confidence interval [CI], 1.001-1.061; P = 0.041) and single leg stance test (odds ratio, 0.99; 95% CI, 0.978-0.996; P = 0.006), but not to step length variability, age, and sex. CONCLUSIONS: Lower walking efficiency increases energy expenditure in children with developmental coordination disorder trait. Interventions to improve walking efficiency could improve the physical function and participation of these children.

Gait performance and dual-task costs in school-aged children with Down syndrome.

OBJECTIVE: This cross-sectional observational study aimed to assess gait performance, its correlation with physical functions, and its dual-task costs in children with Down syndrome (DS), to investigate their gait adaptations. METHODS: Gait performance with or without movie-watching tasks was evaluated in 17 children with DS (age, 6-12 years) and 51 age- and sex-matched controls, using three-dimensional gait analysis. We compared participants' demographics, physical functions, and gait performance without tasks between the two groups. In the DS group, correlations between physical functions, the intelligence quotient, and gait variables were assessed. Dual-task costs for gait variables were also compared between the two groups. RESULTS: Children with DS showed poorer balance function and muscle strength and lower gait quality than the control group. In the DS group, there was a significant positive correlation between gait speed, step length, and intelligence quotient. There were no correlations between the balance function, muscle strength, intelligence quotient, and gait quality. Dual-task costs for gait speed, step length, and cadence were greater in the DS group; however, there was no significant difference in dual-task costs for gait quality between the two groups. CONCLUSION: These findings highlight the importance of providing appropriate interventions for motor functions in school-aged children with DS based on their gait performance in single- and dual-task conditions, as well as on their intelligence quotient.

Pathological gait in Rett syndrome: Quantitative evaluation using three-dimensional gait analysis.

OBJECTIVES: Ataxic-rigid gait is a characteristic gait pathology in patients with Rett syndrome (RTT). In the present study, we aimed to quantitatively evaluate gait pathology in patients with RTT using three-dimensional gait analysis (3DGA). METHODS: We performed 3DGA in 11 patients with RTT ranging from 5 to 18 years (median age, 9 years) and in 33 age-matched healthy female controls. We compared the results of 3DGA, including spatiotemporal gait parameters and comprehensive indices of gait kinematics, such as the Gait Deviation Index (GDI) and Gait Profile Score (GPS), between the two groups. The GPS consists of nine sub-indices called Gait Variable Scores (GVSs). Decline in GDI or elevation of GPS and GVS indicated greater abnormal gait pathology. RESULTS: The patients demonstrated significantly slower walking speed, lower step length/length of the lower extremities, lower cadence, wider step width, and higher coefficient of variation of step length than the controls. Moreover, the patients had a lower GDI and higher GPS than the controls. The patients also exhibited higher GVSs for eight out of nine gait kinematics, particularly the sagittal plane in the pelvis, hip, knee, and ankle joint; coronal plane in the pelvis and hip joint; and horizontal plane in the pelvis than the controls. CONCLUSIONS: Quantitative evaluation of gait pathology in patients with RTT is possible using 3DGA. We found that in addition to ataxic-rigid gait, abnormalities in the coronal plane of the pelvis and hip joint and the horizontal plane of the pelvis were prominent.

Förster resonance energy transfer-based kinase mutation phenotyping reveals an aberrant facilitation of Ca2+/calmodulin-dependent CaMKIIα activity in de novo mutations related to intellectual disability.

CaMKIIα plays a fundamental role in learning and memory and is a key determinant of synaptic plasticity. Its kinase activity is regulated by the binding of Ca2+/CaM and by autophosphorylation that operates in an activity-dependent manner. Though many mutations in CAMK2A were linked to a variety of neurological disorders, the multiplicity of its functional substrates renders the systematic molecular phenotyping challenging. In this study, we report a new case of CAMK2A P212L, a recurrent mutation, in a patient with an intellectual disability. To quantify the effect of this mutation, we developed a FRET-based kinase phenotyping strategy and measured aberrance in Ca2+/CaM-dependent activation dynamics in vitro and in synaptically connected neurons. CaMKIIα P212L revealed a significantly facilitated Ca2+/CaM-dependent activation in vitro. Consistently, this mutant showed faster activation and more delayed inactivation in neurons. More prolonged kinase activation was also accompanied by a leftward shift in the CaMKIIα input frequency tuning curve. In keeping with this, molecular phenotyping of other reported CAMK2A de novo mutations linked to intellectual disability revealed aberrant facilitation of Ca2+/CaM-dependent activation of CaMKIIα in most cases. Finally, the pharmacological reversal of CAMK2A P212L phenotype in neurons was demonstrated using an FDA-approved NMDA receptor antagonist memantine, providing a basis for targeted therapeutics in CAMK2A-linked intellectual disability. Taken together, FRET-based kinase mutation phenotyping sheds light on the biological impact of CAMK2A mutations and provides a selective, sensitive, quantitative, and scalable strategy for gaining novel insights into the molecular etiology of intellectual disability.

Whole-exome analysis of 177 pediatric patients with undiagnosed diseases.

Recently, whole-exome sequencing (WES) has been used for genetic diagnoses of patients who remain otherwise undiagnosed. WES was performed in 177 Japanese patients with undiagnosed conditions who were referred to the Tokai regional branch of the Initiative on Rare and Undiagnosed Diseases (IRUD) (TOKAI-IRUD). This study included only patients who had not previously received genome-wide testing. Review meetings with specialists in various medical fields were held to evaluate the genetic diagnosis in each case, which was based on the guidelines of the American College of Medical Genetics and Genomics. WES identified diagnostic single-nucleotide variants in 66 patients and copy number variants (CNVs) in 11 patients. Additionally, a patient was diagnosed with Angelman syndrome with a complex clinical phenotype upon detection of a paternally derived uniparental disomy (UPD) [upd(15)pat] wherein the patient carried a homozygous DUOX2 p.E520D variant in the UPD region. Functional analysis confirmed that this DUOX2 variant was a loss-of-function missense substitution and the primary cause of congenital hypothyroidism. A significantly higher proportion of genetic diagnoses was achieved compared to previous reports (44%, 78/177 vs. 24-35%, respectively), probably due to detailed discussions and the higher rate of CNV detection.

Comprehensive Volumetric Analysis of Mecp2-Null Mouse Model for Rett Syndrome by T2-Weighted 3D Magnetic Resonance Imaging.

Rett syndrome (RTT) is a severe progressive neurodevelopmental disorder characterized by various neurological symptoms. Almost all RTT cases are caused by mutations in the X-linked methyl-CpG-binding protein 2 (MeCP2) gene, and several mouse models have been established to understand the disease. However, the neuroanatomical abnormalities in each brain region of RTT mouse models have not been fully understood. Here, we investigated the global and local neuroanatomy of the Mecp2 gene-deleted RTT model (Mecp2-KO) mouse brain using T2-weighted 3D magnetic resonance imaging with different morphometry to clarify the brain structural abnormalities that are involved in the pathophysiology of RTT. We found a significant reduction in global and almost all local volumes in the brain of Mecp2-KO mice. In addition, a detailed comparative analysis identified specific volume reductions in several brain regions in the Mecp2-deficient brain. Our analysis also revealed that the Mecp2-deficient brain shows changes in hemispheric asymmetry in several brain regions. These findings suggest that MeCP2 affects not only the whole-brain volume but also the region-specific brain structure. Our study provides a framework for neuroanatomical studies of a mouse model of RTT.

Quantitative Three-Dimensional Gait Evaluation in Patients With Glucose Transporter 1 Deficiency Syndrome.

BACKGROUND: Of the patients with glucose transporter 1 deficiency syndrome (GLUT1-DS), 90% have a pathologic gait. Ataxic-spastic and ataxic gaits are seen in 35% of patients each. A ketogenic diet and modified Atkins diet (MAD) are effective therapy in GLUT1-DS in terms of both the seizures and movement disorder. A three-dimensional gait analysis (3DGA) system can be used to evaluate gait quantitatively using spatiotemporal data and gait kinematics. We performed 3DGA in three ambulatory patients with GLUT1-DS to evaluate the characteristics of their gait pathology, and we compared the gait variables before and after enhancing the MAD in one patient. METHODS: After examination by pediatric neurologists and pediatric orthopedic surgeons, 3DGA was performed. We assessed walking speed, step length, step width, gait variability, Gait Deviation Index (GDI), Gait Profile Score (GPS), and Gait Variable Score (GVS). RESULTS: All three patients had a low GDI and high GPS, comprehensive indices of gait pathology. The unstable gait pattern featured a wide step width in one patient and high gait variability in two patients. In the sagittal plane, the patients had increased GVSs in the knee and ankle joints due to excessive knee flexion or extension and excessive ankle plantarflexion. In the horizontal plane, the patients had increased GVSs in the pelvis, hips, and foot due to excessive rotation during walking. After enhancing the MAD, GDI, GPS, and GVSs improved. CONCLUSIONS: 3DGA has potential for quantifying the characteristics of gait pathology and its improvement with dietary therapy in patients with GLUT1-DS.