Two Siblings with Cerebellar Ataxia, Mental Retardation, and Disequilibrium Syndrome 4 and a Novel Variant of ATP8A2.

Cerebellar ataxia, mental retardation, and disequilibrium syndrome 4 (CAMRQ4) is early onset neuromotor disorder and intellectual disabilities caused by variants of ATP8A2. We report sibling cases and systematically analyze previous literature to increase our understanding of CAMRQ4. Japanese siblings presented with athetotic movements at 1 and 2 months of age.

A sublethal ATP11A mutation associated with neurological deterioration causes aberrant phosphatidylcholine flipping in plasma membranes.

ATP11A translocates phosphatidylserine (PtdSer), but not phosphatidylcholine (PtdCho), from the outer to the inner leaflet of plasma membranes, thereby maintaining the asymmetric distribution of PtdSer. Here, we detected a de novo heterozygous point mutation of ATP11A in a patient with developmental delays and neurological deterioration. Mice carrying the corresponding mutation died perinatally of neurological disorders.

A 23-year follow-up report of juvenile-onset Sandhoff disease presenting with a motor neuron disease phenotype and a novel variant.

Background: The clinical severity of Sandhoff disease is known to vary widely. Furthermore, long-term follow-up report is very limited in the literature.

Case Presentation: We present a long-term follow-up report of a patient with juvenile-onset Sandhoff disease with a motor neuron disease phenotype.

Recurrent de novo MAPK8IP3 variants cause neurological phenotypes.

c-Jun-amino-terminal kinase-interacting protein 3 (JIP3), encoded by MAPK8IP3, is an adaptor protein of the kinesin-1 complex and essential for axonal transport in neurons. However, an association between MAPK8IP3 variants and human disease has not been established. We identified 5 individuals from four families with recurrent de novo variants c.

A novel homozygous mutation of the TFG gene in a patient with early onset spastic paraplegia and later onset sensorimotor polyneuropathy.

The tropomyosin-receptor kinase fused gene (TFG) has recently been implicated in several distinct hereditary disorders, including the autosomal-recessive form of complicated hereditary spastic paraplegia called SPG57. Previously, three homozygous variants of the TFG gene were reported in five families with SPG57, in which early onset spastic paraplegia, optic atrophy, and peripheral neuropathy were variably identified. Here, we present the first Japanese patient with SPG57, and have added a homozygous p.

The first report of Japanese patients with asparagine synthetase deficiency.

Background: Asparagine synthetase (ASNS) deficiency was recently discovered as a metabolic disorder of non-essential amino acids, and presents as severe progressive microcephaly, intellectual disorder, dyskinetic quadriplegia, and intractable seizures.

Methods: Two Japanese children with progressive microcephaly born to unrelated patients were analyzed by whole exome sequencing and novel ASNS mutations were identified. The effects of the ASNS mutations were analyzed by structural evaluation and in silico predictions.

The molecular and phenotypic spectrum of IQSEC2-related epilepsy.

Objective: IQSEC2 is an X-linked gene associated with intellectual disability (ID) and epilepsy. Herein we characterize the epilepsy/epileptic encephalopathy of patients with IQSEC2 pathogenic variants.

Methods: Forty-eight patients with IQSEC2 variants were identified worldwide through Medline search.

Patchy white matter hyperintensity in ring chromosome 18 syndrome.

Ring chromosome 18 syndrome is a chromosomal abnormality in which partial deletions occur at both ends of chromosome 18, that is, distally on the short and long arms. Previously reported brain magnetic resonance imaging (MRI) abnormalities include diffuse hyperintensity in the white matter, which has been regarded as hypomyelination because the gene for myelin basic protein production is located on the long arm of chromosome 18. We report the case of a 14-year-old boy with ring chromosome 18 syndrome, whose MRI showed patchy asymmetrical T2 and fluid-attenuated inversion-recovery hyperintensities in the deep white matter as well as diffuse hypomyelination.

High-dose phenobarbital with intermittent short-acting barbiturates for acute encephalitis with refractory, repetitive partial seizures.

Acute encephalitis with refractory, repetitive partial seizures (AERRPS) is characterized by repetitive seizures during the acute and chronic phases and has a poor neurological outcome. Burst-suppression coma via continuous i.v.

First Japanese variant of late infantile neuronal ceroid lipofuscinosis caused by novel CLN6 mutations.

The clinical phenotypes of neuronal ceroid lipofuscinoses (NCLs) have been determined based on the age of onset and clinical symptoms. NCLs with onset between age 2 and 4years are known as late infantile neuronal ceroid lipofuscinoses (LINCLs). The clinical features of LINCLs include visual loss and progressive myoclonus epilepsy (PME) characterized by myoclonus, seizures, ataxia, and both mental and motor deterioration.

Asymptomatic congenital cytomegalovirus infection with neurological sequelae: A retrospective study using umbilical cord.

Background: Congenital cytomegalovirus (CMV) infection causes various neurological sequelae. However, most infected infants are asymptomatic at birth, and retrospective diagnosis is difficult beyond the neonatal period.

Objective: This study aimed to investigate the aspects of neurological sequelae associated with asymptomatic congenital CMV infection.

FDG-PET study of patients with Leigh syndrome.

We conducted a [(18)F]fluorodeoxyglucose positron emission tomography (FDG-PET) study in five patients (median age 11 (range 4-13) years) with Leigh syndrome to evaluate its usefulness for understanding the functional brain dysfunction in this disease and in future drug trials. Four patients were found to have reported mitochondrial DNA gene mutations. The brain T2-weighted magnetic resonance imaging (MRI) showed high-intensity areas in the putamen bilaterally in five patients, caudate bilaterally in four, thalamus bilaterally in two, and brainstem in one.

De novo GABRA1 mutations in Ohtahara and West syndromes.

Objective: GABRA1 mutations have been identified in patients with familial juvenile myoclonic epilepsy, sporadic childhood absence epilepsy, and idiopathic familial generalized epilepsy. In addition, de novo GABRA1 mutations were recently reported in a patient with infantile spasms and four patients with Dravet syndrome. Those reports suggest that GABRA1 mutations are associated with infantile epilepsy including early onset epileptic encephalopathies.

Acute encephalitis with refractory, repetitive partial seizures: Pathological findings and a new therapeutic approach using tacrolimus.

Acute encephalitis with refractory, repetitive partial seizures (AERRPS) is characterized by prolonged severe seizures and a high-grade fever. We experienced a boy with severe AERRPS with frequent partial seizures that exhibited right-side predominance. The patient required the continuous intravenous administration of many antiepileptic drugs and respirator management for several months.

Manifestations and characteristics of congenital adrenal hyperplasia-associated encephalopathy.

Background: This study aimed to clarify the characteristics of acute encephalopathic episodes in patients with congenital adrenal hyperplasia (CAH), which we termed "CAH-associated encephalopathy (CAHE)."

Methods: This retrospective study was conducted using a questionnaire as a nationwide survey of patients with CAH with acute encephalopathy and related episodes.

Results: Fifteen patients were recruited on the bases of clinical data that supported a diagnosis of CAHE.

The lack of antiepileptic drugs and worsening of seizures among physically handicapped patients with epilepsy during the Great East Japan Earthquake.

Background: Takuto Rehabilitation Center for Children is located in Sendai, the capital of the Miyagi prefecture, and faces the Pacific Ocean. The tsunami caused by the Great East Japan Earthquake resulted in tremendous damage to this region. Many physically handicapped patients with epilepsy who are treated at our hospital could not obtain medicine.

De novo KCNH1 mutations in four patients with syndromic developmental delay, hypotonia and seizures.

The voltage-gated Kv10.1 potassium channel, also known as ether-a-go-go-related gene 1, encoded by KCNH1 (potassium voltage-gated channel, subfamily H (eag related), member 1) is predominantly expressed in the central nervous system. Recently, de novo missense KCNH1 mutations have been identified in six patients with Zimmermann-Laband syndrome and in four patients with Temple-Baraitser syndrome.

Two cases of early-onset myoclonic seizures with continuous parietal delta activity caused by EEF1A2 mutations.

Background: Mutations in the elongation factor 1 alpha 2 (EEF1A2) gene have recently been shown to cause severe intellectual disability with early-onset epilepsy. The specific manifestations of mutations in this gene remain unknown.

Case Report: We report two cases of severe intellectual disability accompanied by early-onset epilepsy with continuous delta activity evident on electroencephalography.

Genetic heterogeneity in 26 infants with a hypomyelinating leukodystrophy.

T2 hyperintensity of brain white matter lesions detected by magnetic resonance imaging (MRI) are characteristic of a heterogeneous group of diseases. Persistent T2 high intensity in combination with T1 iso- or high intensity of white matter in infants indicates a lack of normal myelination, that is, hypomyelination. However, the precise diagnosis of hypomyelinating leukodystrophy based solely on MRI findings can be difficult, especially in the early stage of the disease.

Neuroepidemiology of Porencephaly, Schizencephaly, and Hydranencephaly in Miyagi Prefecture, Japan.

Background: No population-based surveys of porencephaly, schizencephaly, and hydranencephaly have been conducted in Japan or other Asian countries. We performed a neuroepidemiologic analysis to elucidate the incidence of porencephaly, schizencephaly, and hydranencephaly in Miyagi prefecture, Japan, during 2007-2011.

Methods: We sent inquiry forms in February 2012 to three neonatal intensive care units, 25 divisions of orthopedic surgery in municipal hospitals, 33 divisions of pediatrics including one university hospital, municipal hospitals, pediatric practitioners, and institutions for physically handicapped children located in Miyagi prefecture.

Outcome of hemiplegic cerebral palsy born at term depends on its etiology.

Objectives: To elucidate the etiology and its relationship to the outcomes of hemiplegic cerebral palsy (HCP).

Participants And Methods: MR images and outcomes of 156 children with HCP born at term and older than three years were investigated in two major centers for cerebral palsy in Japan. Etiologies were classified into perinatal ischemic stroke (PIS), cerebral dysgenesis (CD), and others.

De novo KIF1A mutations cause intellectual deficit, cerebellar atrophy, lower limb spasticity and visual disturbance.

Recently, de novo KIF1A mutations were identified in patients with intellectual disability, spasticity and cerebellar atrophy and/or optic nerve atrophy. In this study, we analyzed a total of 62 families, including 68 patients with genetically unsolved childhood cerebellar atrophy, by whole-exome sequencing (WES). We identified five de novo missense KIF1A mutations, including only one previously reported mutation (p.

GRIN1 mutations cause encephalopathy with infantile-onset epilepsy, and hyperkinetic and stereotyped movement disorders.

Objective: Recently, de novo mutations in GRIN1 have been identified in patients with nonsyndromic intellectual disability and epileptic encephalopathy. Whole exome sequencing (WES) analysis of patients with genetically unsolved epileptic encephalopathies identified four patients with GRIN1 mutations, allowing us to investigate the phenotypic spectrum of GRIN1 mutations.

Methods: Eighty-eight patients with unclassified early onset epileptic encephalopathies (EOEEs) with an age of onset <1 year were analyzed by WES.