Make Bayley III Scores Comparable between United States and German Norms-Development of Conversion Equations.

AIM: Bayley Scales of Infant and Toddler Development (Bayley-III) determines scaled scores and converts these into composite scores. It was shown that applying the German and the U.S. manual leads to different results. This study aims to systematically analyze the differences between the U.S. and German Bayley-III version and to develop conversion equations. METHODS: This simulation study generated a dataset of pairs of U.S. and German Bayley-III composite scores (cognitive: n = 4,416, language: n = 240,000, motor: n = 314,000) by converting the same number of achievable tasks for 48 age groups. Bland-Altman plot and regression analyses were performed to develop conversion equations for all age groups. RESULTS: German and US Bayley-III scores demonstrate distinct slope and interception for cognitive, language, and motor composite scores. Lower developmental performance leads to higher composite scores with U.S. norms compared with German norms (up to 15 points). These differences varied between age groups. With newly developed conversion equations, the results can be converted (R 2 > 0.98). INTERPRETATION: This study confirms systematic differences between U.S. and German Bayley test results due to different reference cohorts. Our data consider the full age range and add conversion equations. These findings need to be acknowledged when comparing Bayley Scores internationally.

Mechanography in children: pediatric references in postural control.

OBJECTIVE: To establish pediatric age- and sex-specific references for measuring postural control with a mechanography plate in a single centre, prospective, normative data study. METHODS: 739 children and adolescents (396 male/343 female) aged 4 to 17 years were studied. Each participant completed the following test sequence three times: Romberg, semi-tandem, tandem, each with eyes open and closed, and a one-leg stand with eyes open, and a single two-legged jump. Normal ranges were determined based on percentile calculations using the LMS method. Results from the two-legged jump were compared to a reference population the single two-legged jump (s2LJ) assessment in 2013. RESULTS: 38 different equilibrium parameters calculated were analysed. Of all parameters Path Length, vCoFmean, Equilibrium Score and Sway Angle showed a low variation within the same age group but high dependency on age and were thus chosen for automated balance assessment. CONCLUSION: Standard values of postural control in healthy children derived from automated balance testing using a mechanography plate were successfully acquired and a subset of parameters for automated balance assessment identified.

Glut1 Deficiency Syndrome (Glut1DS): State of the art in 2020 and recommendations of the international Glut1DS study group.

Glut1 deficiency syndrome (Glut1DS) is a brain energy failure syndrome caused by impaired glucose transport across brain tissue barriers. Glucose diffusion across tissue barriers is facilitated by a family of proteins including glucose transporter type 1 (Glut1). Patients are treated effectively with ketogenic diet therapies (KDT) that provide a supplemental fuel, namely ketone bodies, for brain energy metabolism. The increasing complexity of Glut1DS, since its original description in 1991, now demands an international consensus statement regarding diagnosis and treatment. International experts (n = 23) developed a consensus statement utilizing their collective professional experience, responses to a standardized questionnaire, and serial discussions of wide-ranging issues related to Glut1DS. Key clinical features signaling the onset of Glut1DS are eye-head movement abnormalities, seizures, neurodevelopmental impairment, deceleration of head growth, and movement disorders. Diagnosis is confirmed by the presence of these clinical signs, hypoglycorrhachia documented by lumbar puncture, and genetic analysis showing pathogenic SLC2A1 variants. KDT represent standard choices with Glut1DS-specific recommendations regarding duration, composition, and management. Ongoing research has identified future interventions to restore Glut1 protein content and function. Clinical manifestations are influenced by patient age, genetic complexity, and novel therapeutic interventions. All clinical phenotypes will benefit from a better understanding of Glut1DS natural history throughout the life cycle and from improved guidelines facilitating early diagnosis and prompt treatment. Often, the presenting seizures are treated initially with antiseizure drugs before the cause of the epilepsy is ascertained and appropriate KDT are initiated. Initial drug treatment fails to treat the underlying metabolic disturbance during early brain development, contributing to the long-term disease burden. Impaired development of the brain microvasculature is one such complication of delayed Glut1DS treatment in the postnatal period. This international consensus statement should facilitate prompt diagnosis and guide best standard of care for Glut1DS throughout the life cycle.

10 patients, 10 years - Long term follow-up of cardiovascular risk factors in Glut1 deficiency treated with ketogenic diet therapies: A prospective, multicenter case series.

BACKGROUND AND AIMS: Glut1 Deficiency (Glut1D) is caused by impaired glucose transport into brain. The resulting epileptic encephalopathy and movement disorders can be treated effectively by high-fat carbohydrate-restricted ketogenic diet therapies (KDT) mimicking fasting and providing ketones as an alternative cerebral fuel. Recently 6-24 months follow-ups of epileptic patients reported elevated blood lipids and intima thickening of the carotid artery raising concerns about potential cardiovascular risks by KDT. To clarify potential cardiovascular risks we performed a prospective 10 year follow up of 10 Glut1D patients. METHODS: Between August 2001 and January 2016 we enrolled Glut1D patients on KDT at two hospitals in Germany in this prospective, multicenter case series. The minimal follow up was 10 years. Standard deviation scores (SDS) of body mass index (BMI), total cholesterol (TC), HDL-/LDL cholesterol, and triglycerides (TG) before initiation of KDT were compared with respective values at 6 months, 2, 5 years, and 10 years after initiation. After 10 years on KDT cardiovascular risk, assessed by BMI, carotid intima-media thickness (CIMT) measurement, and blood pressure, was compared to a healthy reference population (n = 550). RESULTS: Baseline and 10 year follow-up investigations were available for 10 individuals with Glut1D on KDT. After two years on KDT BMI increased significantly, while total cholesterol, HDL-cholesterol, and LDL-cholesterol decreased. Within 3-5 years on KDT these differences disappeared, and after 10 years blood lipid parameters reflected the situation at initiation of KDT. Prior to KDT one child had dyslipidaemia, but no child after 10 years on KDT. No significant differences were observed with respect to BMI SDS (p = 0.26), CIMT (p = 0.63) or systolic and diastolic blood pressure (SDS p = 0.11 and p = 0.37, respectively) in Glut1D children treated with KDT for at least 10 years compared to healthy controls. CONCLUSIONS: In contrast to previous short-term reports on adverse effects of KDT, 10-year follow-up did not identify cardiovascular risks of dietary treatment for Glut1D.

Variable White Matter Atrophy and Intellectual Development in a Family With X-linked Creatine Transporter Deficiency Despite Genotypic Homogeneity.

BACKGROUND: The X-linked creatine transporter deficiency (CRTD) caused by an SLC6A8 mutation represents the second most common cause of X-linked intellectual disability. The clinical phenotype ranges from mild to severe intellectual disability, epilepsy, short stature, poor language skills, and autism spectrum disorders. The objective of this study was to investigate phenotypic variability in the context of genotype, cerebral creatine concentration, and volumetric analysis in a family with CRTD. PATIENTS AND METHODS: The clinical phenotype and manifestations of epilepsy were assessed in a Caucasian family with CRTD. DNA sequencing and creatine metabolism analysis confirmed the diagnosis. Cerebral magnetic resonance imaging (cMRI) with voxel-based morphometry and magnetic resonance spectroscopy was performed in all family members. RESULTS: An SLC6A8 missense mutation (c.1169C>T; p.Pro390Leu, exon 8) was detected in four of five individuals. Both male siblings were hemizygous, the mother and the affected sister heterozygous for the mutation. Structural cMRI was normal, whereas voxel-based morphometry analysis showed reduced white matter volume below the first percentile of the reference population of 290 subjects in the more severely affected boy compared with family members and controls. Normalized creatine concentration differed significantly between the individuals (P < 0.005). CONCLUSIONS: There is a broad phenotypic variability in CRTD even in family members with the same mutation. Differences in mental development could be related to atrophy of the subcortical white matter.

Severe Hypertriglyceridemia in Glut1D on Ketogenic Diet.

High-fat ketogenic diets are the only treatment available for Glut1 deficiency (Glut1D). Here, we describe an 8-year-old girl with classical Glut1D responsive to a 3:1 ketogenic diet and ethosuximide. After 3 years on the diet a gradual increase of blood lipids was followed by rapid, severe asymptomatic hypertriglyceridemia (1,910 mg/dL). Serum lipid apheresis was required to determine liver, renal, and pancreatic function. A combination of medium chain triglyceride-oil and a reduction of the ketogenic diet to 1:1 ratio normalized triglyceride levels within days but triggered severe myoclonic seizures requiring comedication with sultiam. Severe hypertriglyceridemia in children with Glut1D on ketogenic diets may be underdiagnosed and harmful. In contrast to congenital hypertriglyceridemias, children with Glut1D may be treated effectively by dietary adjustments alone.

Paroxysmal Nonepileptic Events in Glut1 Deficiency.

View Supplementary Video Movement disorders are a major feature of Glut1 deficiency. As recently identified in adults with paroxysmal exercise-induced dystonia, similar events were reported in pediatric Glut1 deficiency. In a case series, parent videos of regular motor state and paroxysmal events were requested from children with Glut1 deficiency on clinical follow-up. A questionnaire was sent out to 60 families. Videos of nonparoxysmal/paroxysmal states in 3 children illustrated the ataxic-dystonic, choreatiform, and dyskinetic-dystonic nature of paroxysmal events. Fifty-six evaluated questionnaires confirmed this observation in 73% of patients. Events appeared to increase with age, were triggered by low ketosis, sleep deprivation, and physical exercise, and unrelated to sex, hypoglycorrhachia, SLC2A1 mutations, or type of ketogenic diet. We conclude that paroxysmal events are a major clinical feature in Glut1 deficieny, linking the pediatric disease to adult Glut1D-associated exercise-induced paroxysmal dyskinesias.

Oligoclonal bands predict multiple sclerosis in children with optic neuritis.

We retrospectively evaluated predictors of conversion to multiple sclerosis (MS) in 357 children with isolated optic neuritis (ON) as a first demyelinating event who had a median follow-up of 4.0 years. Multiple Cox proportional-hazards regressions revealed abnormal cranial magnet resonance imaging (cMRI; hazard ratio [HR] = 5.94, 95% confidence interval [CI] = 3.39-10.39, p < 0.001), presence of cerebrospinal fluid immunoglobulin G oligoclonal bands (OCB; HR = 3.69, 95% CI = 2.32-5.86, p < 0.001), and age (HR = 1.08 per year of age, 95% CI = 1.02-1.13, p = 0.003) as independent predictors of conversion, whereas sex and laterality (unilateral vs bilateral) had no influence. Combined cMRI and OCB positivity indicated a 26.84-fold higher HR for developing MS compared to double negativity (95% CI = 12.26-58.74, p < 0.001). Accordingly, cerebrospinal fluid analysis may supplement cMRI to determine the risk of MS in children with isolated ON.

PRRT2-related disorders: further PKD and ICCA cases and review of the literature.

Recent studies reported mutations in the gene encoding the proline-rich transmembrane protein 2 (PRRT2) to be causative for paroxysmal kinesigenic dyskinesia (PKD), PKD combined with infantile seizures (ICCA), and benign familial infantile seizures (BFIS). PRRT2 is a presynaptic protein which seems to play an important role in exocytosis and neurotransmitter release. PKD is the most common form of paroxysmal movement disorder characterized by recurrent brief involuntary hyperkinesias triggered by sudden movements. Here, we sequenced PRRT2 in 14 sporadic and 8 familial PKD and ICCA cases of Caucasian origin and identified three novel mutations (c.919C>T/p.Gln307, c.388delG/p.Ala130Profs 46, c.884G>A/p.Arg295Gln) predicting two truncated proteins and one probably damaging point mutation. A review of all published cases is also included. PRRT2 mutations occur more frequently in familial forms of PRRT2-related syndromes (80-100 %) than in sporadic cases (33-46 %) suggesting further heterogeneity in the latter. PRRT2 mutations were rarely described in other forms of paroxysmal dyskinesias deviating from classical PKD, as we report here in one ICCA family without kinesigenic triggers. Mutations are exclusively found in two exons of the PRRT2 gene at a high rate across all syndromes and with one major mutation (c.649dupC) in a mutational hotspot of nine cytosines, which is responsible for 57 % of all cases in all phenotypes. We therefore propose that genetic analysis rapidly performed in early stages of the disease is highly cost-effective and can help to avoid further unnecessary diagnostic and therapeutic interventions.

Ultrasound-guided neuronavigation improves safety of ventricular catheter insertion in preterm infants.

BACKGROUND: Intra-ventricular hemorrhage (IVH) is a frequent cause of shunt-dependent hydrocephalus. The management of IVH in preterm babies remains a challenge both for neonatologists and pediatric neurosurgeons, compounded by the lack of low-risk, validated therapy techniques. OBJECTIVE: The aim of this study was to evaluate the feasibility and safety of a novel technique involving the ultrasound-guided placement of a central catheter connected with a Rickham-Capsule in a cohort of preterm, low-birth-weight babies with post-hemorrhagic hydrocephalus (PHH). METHODS: Eight preterm infants with PHH in which a Rickham-Capsule was placed from 2008-2012 were included. Conventional surgical techniques were used in four preterm infants; whereas in the other four preterm babies ultrasound guided catheter placement was performed with an 8 MegaHertz (MHz) micro convex transducer from LOGIQ 9, GE Healthcare; whereby the anterior fontanel was used as an acoustic window. RESULTS: Overall gestational age was 24-31 weeks, mean age at operation was 20.1 (7-36) days, mean birth weight 972.5±370 g, mean weight at first surgical intervention 1023.75±400.4 g. Six patients had bilateral IVH II-III°, two patients had parenchymal involvement. Using the conventional approach, incorrect catheter placement occurred in one of four patients below 1000 g, whereas none of the ultrasound guided cases needed correction. CONCLUSIONS: Ultrasound-guided neuronavigation represents a relevant tool in the treatment of hydrocephalus in preterm infants through increased accuracy in placement of a central catheter connected to a Rickham-Capsule. The benefit of utilizing this form of neuronavigation needs to be assessed through corresponding standardized studies.

Expression of Epstein-Barr virus (EBV)-encoded latent membrane proteins and STAT3 activation in nasopharyngeal carcinoma.

The Epstein-Barr virus (EBV) is associated with virtually all cases of undifferentiated nasopharyngeal carcinoma (NPC), and it was proposed that the EBV-encoded transforming protein, latent membrane protein (LMP) 1, may play a role in the neoplastic process. It was proposed recently that LMP1 expression in epithelial cells may be regulated through a loop involving activated signal transducer and activator of transcription 3 (STAT3), LMP1, LMP1-mediated induction of interleukin (IL)-6 expression and STAT3 activation through the IL-6 receptor. This autoregulatory loop may be suppressed by another viral protein, LMP2A, an effect which in turn can be overcome by exogenous IL-6. Here we show that, as expected, expression of LMP1 and LMP2A tend to be exclusive in NPC tumours. Rare cases showing a co-expression of both proteins can be explained by STAT3 activation via the receptors for IL-6 or epidermal growth factor. STAT3 activation was a consistent feature of NPC tumour cells. However, in most cases, this was not accompanied by detectable expression of LMP1, suggesting either that LMP2A expression may suffice to suppress LMP1 expression or that additional factors may be operational. This study emphasises the need to correlate in vitro results with observational studies of ex vivo tumour tissues.

Expression of the Epstein-Barr virus (EBV)-encoded latent membrane protein 2A (LMP2A) in EBV-associated nasopharyngeal carcinoma.

The Epstein-Barr virus (EBV) is associated with virtually all cases of undifferentiated nasopharyngeal carcinoma (NPC) and has been classified as a group I carcinogen. In addition to its potential role in the pathogenesis of NPC, EBV also provides a possible target for immunotherapy of NPC, since a limited number of viral genes are expressed in the neoplastic cells. The EBV-encoded latent membrane protein 2A (LMP2A) is considered a promising target since it provides epitopes recognized by EBV-specific T-cells. Using immunohistochemistry, the present study shows that LMP2A is expressed at the protein level in the neoplastic cells of 16 of 35 (45.7%) NPC biopsies. This finding provides further evidence suggesting that NPC tumour cells may be susceptible to lysis by cytotoxic T-cells directed against LMP2A and should encourage efforts to develop immunotherapeutic approaches for the treatment of NPC.