小坂 仁

We diagnosed three siblings from consanguineous east Asian parents with leukoencephalopathy with brainstem and spinal cord involvement and high lactate (LBSL) from characteristic MRI, MRS findings and a homozygous mutation in the DARS2 gene. The neurological symptoms of the three patients consisted of psychomotor developmental delay, cerebellar ataxia since infancy, spasticity in the initial phase and peripheral neuropathy in later stages. Their mental development was delayed, but did not deteriorate. MRI signal abnormalities included the same abnormalities reported previously but tended to be more extensive. Signal abnormalities in the cerebral and cerebellar white matter were homogeneous and confluent from early stages. In addition, other tract such as the central tegmental tract was involved. Furthermore, an atrophic change in the cerebral white matter was observed on follow-up in one case. Two of the patients were autopsied and neuropathological findings revealed characteristic vacuolar changes in the white matter of the cerebrum, cerebellum and the nerve tracts of the brain stem and spinal cord. The central myelin sheath showed intralamellar splitting by electron microscopy. These findings were consistent to a spongy degeneration in the diffuse white matter of the brain, or spongiform leukoencephalopathy. In addition, peripheral nerves showed both axonal degeneration and abnormal myelin structures. We discussed the relationship between deficits in mitochondrial aspartyl-tRNA synthetase activity and the neuropathology observed. © 2012 The Japanese Society of Child Neurology.

髄鞘の構成成分のうち, 最も量的に豊富な蛋白はプロテオリピドプロテイン (proteolipid protein 1; PLP1) であり, この蛋白をコードするPLP1が先天性白質形成不全症の主要疾患, Pelizaeus-Merzbacher病 (PMD) の原因である. 典型例の診断は比較的容易であるが, 軽症群では, 眼振が目立たず, 単に発達遅滞あるいは痙性麻痺と診断されており, MRI検査からPLP1異常が疑われて診断がつく場合も多い. また, PMD以外にも新しい白質形成不全症が次々と明らかになってきている. これらの実例を自験例から紹介しながら, この20年の進歩を概観し, 最後に幹細胞移植治療について触れる.

先天性大脳白質形成不全症は, 中枢神経系の髄鞘形成不全を主体とする疾患の総称である. その代表的疾患であるPelizaeus-Merzbacher病 (PMD) はX染色体上に存在するPLP1遺伝子の変異によって起こる. 本稿では, まず, 最も頻度の高いPLP1重複が見いだされた経緯とその後の遺伝子診断やゲノム機序の解明に至る経過について概説する. 次に, 小胞体ストレスという細胞病態を標的としたPMDの治療法開発研究の現在の取り組みについて紹介する. 最後に, 先天性大脳白質形成不全症の疾患分類や全国疫学調査の概要などの臨床的基盤研究と今後の展望について述べる.

けいれんで発症し、精神症状や不随意運動を呈し、血液および髄液から抗NMDA受容体抗体が検出され、非腫瘍性抗NMDA受容体抗体脳炎と診断した8歳男児の症例を報告した。急性期のステロイドパルス療法やガンマグロブリン療法は効果がなかったが、月1回合計3クールのcyclophosphamide(CPA)のパルス療法(500mg/m2)後から髄液NMDA抗体価と平行して、症状が急速に改善し始め、発症6ヵ月後に明らかな神経学的合併症なく治癒した。CPA療法は、本症の小児における免疫抑制療法として、ステロイド療法やガンマグロブリン療法とともに考慮されるべき治療である。(著者抄録)

Background: Creatine transporter deficiency is a monogenic cause of X-linked intellectual disability. Since its first description in 2001 several case reports have been published but an overview of phenotype, genotype and phenotype-genotype correlation has been lacking. Methods: We performed a retrospective study of clinical, biochemical and molecular genetic data of 101 males with X-linked creatine transporter deficiency from 85 families with a pathogenic mutation in the creatine transporter gene (SLC6A8). Results and conclusions: Most patients developed moderate to severe intellectual disability mild intellectual disability was rare in adult patients. Speech language development was especially delayed but almost a third of the patients were able to speak in sentences. Besides behavioural problems and seizures, mild to moderate motor dysfunction, including extrapyramidal movement abnormalities, and gastrointestinal problems were frequent clinical features. Urinary creatine to creatinine ratio proved to be a reliable screening method besides MR spectroscopy, molecular genetic testing and creatine uptake studies, allowing definition of diagnostic guidelines. A third of patients had a de novo mutation in the SLC6A8 gene. Mothers with an affected son with a de novo mutation should be counselled about a recurrence risk in further pregnancies due to the possibility of low level somatic or germline mosaicism. Missense mutations with residual activity might be associated with a milder phenotype and large deletions extending beyond the 30 end of the SLC6A8 gene with a more severe phenotype. Evaluation of the biochemical phenotype revealed unexpected high creatine levels in cerebrospinal fluid suggesting that the brain is able to synthesise creatine and that the cerebral creatine deficiency is caused by a defect in the reuptake of creatine within the neurones.

Treatment of west syndrome in patients with tuberous sclerosis, the relevant effective period and doses of vigabatrin (VGB) to avoid serious side effects still needs further investigation. We report on a Japanese girl who showed good results with a very low dose of VGB. Tonic spasms appeared at 5 mo of age. Adrenocorticotropic hormone therapy resulted in incomplete seizure control. VGB at the lowest practical dose (30 mg/kg/d) showed complete control after 3 d. With reduction of the dose to 10 mg/kg/d, side effects such as hyperactivity, irritability, and sleep disturbances improved. She was seizure-free for the next 6 mo with an improved developmental quotient. Ophthalmological evaluation revealed no abnormality. The present case illustrates that low-dose VGB therapy (10 mg/kg/d) has fewer side effects and may bring prompt seizure control in west syndrome with tuberous sclerosis. © 2013 - IOS Press and the authors.

Objective: Recently, COL4A1 mutations have been reported in porencephaly and other cerebral vascular diseases, often associated with ocular, renal, and muscular features. In this study, we aimed to clarify the phenotypic spectrum and incidence of COL4A1 mutations. ' Methods: We screened for COL4A1 mutations in 61 patients with porencephaly and 10 patients with schizencephaly, which may be similarly caused by disturbed vascular supply leading to cerebral degeneration, but can be distinguished depending on time of insult. Results: COL4A1 mutations were identified in 15 patients (21%, 10 mutations in porencephaly and 5 mutations in schizencephaly), who showed a variety of associated findings, including intracranial calcification, focal cortical dysplasia, pontocerebellar atrophy, ocular abnormalities, myopathy, elevated serum creatine kinase levels, and hemolytic anemia. Mutations include 10 missense, a nonsense, a frameshift, and 3 splice site mutations. Five mutations were confirmed as de novo events. One mutation was cosegregated with familial porencephaly, and 2 mutations were inherited from asymptomatic parents. Aberrant splicing was demonstrated by reverse transcriptase polymerase chain reaction analyses in 2 patients with splice site mutations. Interpretation: Our study first confirmed that COL4A1 mutations are associated with schizencephaly and hemolytic anemia. Based on the finding that COL4A1 mutations were frequent in patients with porencephaly and schizencephaly, genetic testing for COL4A1 should be considered for children with these conditions. ANN NEUROL 2013;73:48-57

We reported on a male patient with rare leukoencephalopathy and skeletal abnormalities. The condition was first noticed as a developmental delay, nystagmus and ataxia at 1 year of age. At 4 years of age, he was diagnosed as hypomyelination with skeletal abnormalities from clinical features, brain magnetic resonance imaging (MRI) and skeletal X-rays. His brain MRI revealed diffuse hypomyelination. These findings suggested the classical type of PelizaeusMerzbacher disease (PMD) caused by proteolipid protein (PLP)-1 gene or PelizaeusMerzbacher-like disease (PMLD). However, we found neither mutation nor duplication of PLP-1. The patient had severe growth retardation and general skeletal dysplasia compatible with spondylo-epi-metaphyseal dysplasia; however the mutation of discoidin domain receptor (DDR) 2 gene was absent. The co-morbidity of hypomyelination with skeletal abnormalities is rare. We performed array CGH and no causal copy number variation was recognized. Alternatively, this condition may have been caused by a mutation of the gene encoding a molecule that functions in both cerebral myelination and skeletal development. (c) 2012 Wiley Periodicals, Inc.

We report on an 8-year-old boy with non-paraneoplastic anti-NMDA receptor (NMDAR) encephalitis, who presented with psychotic symptoms and involuntary movement following an intractable seizure. His serum and CSF tested positive for anti-NMDAR antibodies. He received an initial immunotherapy consisting of methylprednisolone pulse therapy (mPSL) and intravenous immunoglobulin therapy (IVIg), without any clinical improvement. He had three cycles of monthly cyclophosphamide pulse therapy (500 mg/m2), and his clinical condition started to improve gradually two weeks after the first cycle, without any side effects. Six months after onset, he tested normal upon standard neurological examination. Cyclophosphamide therapy should be considered for children with anti-NMDAR encephalitis, as well as mPSL and IVIg.

Background and Purpose: Influenza viral infection, which results in central nervous system dysfunction, is a major cause of acute encephalopathy (AE). The purpose of this study was to investigate the changes in the concentrations of brain metabolites in children with AE using single-voxel magnetic resonance spectroscopy (MRS) and to provide diagnostic information about the relationship between the symptoms of AE and metabolite concentrations. Materials and Methods: The subjects were 10 children (mean age: 6.2 years; range: 1-13) with AE caused by the novel influenza A virus responsible for the 2009 influenza pandemic. The serial MRS data (TE/TR=30/5000 ms, 3 T) acquired from the basal ganglia (BG) and centrum semiovale (CS) of each patient were categorized into three periods: (1) initial neurological symptom presentation and the start of treatment (n=10), (2) short-term follow-up (n=9) and (3) long-term follow-up (n=3). As controls, the magnetic resonance (MR) spectra of eight age-matched children were also investigated. Results: In both regions, the concentrations of the major metabolites (N-acetylaspartate, creatine, choline, myo-inositol, glutamate/glutamine complex and glutamate) only showed minor fluctuations between the three periods. On the other hand, higher levels of taurine (Tau) were observed in the BG during the second period (P=.005), and increased levels of glucose were observed in the CS during the first (P=.005) and second (P=.036) periods. Conclusions: Serial monitoring of brain metabolite changes was carried out with a clinical MR system. The concentrations of major metabolites only displayed very minor fluctuations in response to mild H1N1-related AE. However, a higher Tau concentration was found to be associated with neurological symptoms. Further studies are required to improve our understanding of the detailed activity of Tau in AE. (C) 2012 Elsevier Inc. All rights reserved.

We report two patients with Leigh syndrome that showed a combination of facial dysmorphism and MRI imaging indicating an SURF1 deficiency, which was confirmed by sequence analysis. Case 1 is a 3-year-old girl with failure to thrive and developmental delay. She presented with tachypnea at rest and displayed facial dysmorphism including frontal bossing, lateral displacement of inner canthi, esotropia, maxillary hypoplasia, slightly upturned nostril, and hypertrichosis dominant on the forehead and extremities. Case 2 is an 8-year-old boy with respiratory failure. He had been diagnosed as selective complex IV deficiency. Case 2 displayed facial dysmorphism and hypertrichosis. Since both patients displayed characteristic facial dysmorphism and MRI findings, we sequenced the SURF1 gene and identified two heterozygous mutations; c.49+1 G>T and c.752_753del in Case I, and homozygous c.743 C>A in Case 2. For patients with Leigh syndrome showing these facial dysmorphism and hypertrichosis, sequence analysis of the SURF1 gene may be useful. (C) 2012 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

A 4-year-old boy presented with a sudden onset of nasal escape of fluids, nasal speech, and difficulty placing his left arm through a sleeve. Neurologic examination indicated a unilateral cranial IX and X and contralateral XI nerve palsy that was considered idiopathic. Palsy of cranial nerves IX, X, and XI is rare in childhood, and few reports have described this condition. Our patient received prednisolone for 1 week and demonstrated complete recovery within several weeks. We suggest that aggressive therapy is unnecessary for patients with idiopathic cranial polyneuropathy. The pathogenesis of this condition may involve an immunologic mechanism. (C) 2012 Elsevier Inc. All rights reserved.

Cerebral creatine deficiency syndromes (CCDS) are caused by genetic defects in l-arginine:glycine amidinotransferase, guanidinoacetate methyltransferase or creatine transporter 1. CCDS are characterized by abnormal concentrations of urinary creatine (CR), guanidinoacetic acid (GA), or creatinine (CN). In this study, we describe a simple HPLC method to determine the concentrations of CR, GA, and CN using a weak-acid ion chromatography column with a UV detector without any derivatization. CR, GA, and CN were separated clearly with the retention times (mean +/- A SD, n = 3) of 5.54 +/- A 0.0035 min for CR, 6.41 +/- A 0.0079 min for GA, and 13.53 +/- A 0.046 min for CN. This new method should provide a simple screening test for the diagnosis of CCDS.

Purpose: Ohtahara syndrome (OS) is one of the most severe and earliest forms of epilepsy. STXBP1 and ARX mutations have been reported in patients with OS. In this study, we aimed to identify new genes involved in OS by copy number analysis and whole exome sequencing. Methods: Copy number analysis and whole exome sequencing were performed in 34 and 12 patients with OS, respectively. Fluorescence in situ hybridization, quantitative polymerase chain reaction (PCR), and breakpoint-specific and reverse-transcriptase PCR analyses were performed to characterize a deletion. Immunoblotting using lymphoblastoid cells was done to examine expression of CASK protein. Key Findings: Genomic microarray analysis revealed a 111-kb deletion involving exon 2 of CASK at Xp11.4 in a male patient. The deletion was inherited from his mother, who was somatic mosaic for the deletion. Sequencing of the mutant transcript expressed in lymphoblastoid cell lines derived from the patient confirmed the deletion of exon 2 in the mutant transcript with a premature stop codon. Whole exome sequencing identified another male patient who was harboring a c.1A>G mutation in CASK, which occurred de novo. Both patients showed severe cerebellar hypoplasia along with other congenital anomalies such as micrognathia, a high arched palate, and finger anomalies. No CASK protein was detected by immuno-blotting in lymphoblastoid cells derived from two patients. Significance: The detected mutations are highly likely to cause the loss of function of the CASK protein in male individuals. CASK mutations have been reported in patients with intellectual disability with microcephaly and pontocerebellar hypoplasia or congenital nystagmus, and those with FG syndrome. Our data expand the clinical spectrum of CASK mutations to include OS with cerebellar hypoplasia and congenital anomalies at the most severe end.

Recent studies have shown that aberrations of CDKL5 in female patients cause early-onset intractable seizures, severe developmental delay or regression, and Rett syndrome-like features. We report on a Japanese girl with early-onset epileptic encephalopathy, hypotonia, developmental regression, and Rett syndrome-like features. The patient showed generalized tonic seizures, and later, massive myoclonus induced by phone and light stimuli. Brain magnetic resonance imaging showed no structural brain anomalies but cerebral atrophy. Electroencephalogram showed frontal dominant diffuse poly spikes and waves. Through copy number analysis by genomic microarray, we found a microdeletion at Xp22.13. A de novo 137-kb deletion, involving exons 5-21 of CDKL5, RS1, and part of PPEF1 gene, was confirmed by quantitative PCR and breakpoint specific PCR analyses. Our report suggests that the clinical features associated with CDKL5 deletions could be implicated in Japanese patients, and that genetic testing of CDKL5, including both sequencing and deletion analyses, should be considered in girls with early-onset epileptic encephalopathy and RTT-like features. (C) 2011 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

PLP1 amino acid substitutions cause accumulation of misfolded protein and induce endoplasmic reticulum (ER) stress, causing Pelizaeus-Merzbacher disease (PMD), a hypomyelinating disorder of the central nerve system. Currently no effective therapy is available for PMD. Promoted by its curative effects in other genetic disease models caused by similar molecular mechanisms, we tested if curcumin, a dietary compound, can rescue the lethal phenotype of a PMD mouse model (myelin synthesis deficient, msd). Curcumin was administered orally to myelin synthesis deficit (msd) mice at 180 mg.kg(-1)day(-1) from the postnatal day 3. We evaluated general and motor status, changes in myelination and apoptosis of oligodendrocytes by neuropathological and biochemical examination, and transcription levels for ER-related molecules. We also examined the pharmacological effect of curcumin in cell culture system. Oral curcumin treatment resulted in 25% longer survival (p<0.01). In addition, oligodendrocytes undergoing apoptosis were reduced in number (p<0.05). However, no apparent improvement in motor function, neurological phenotype, and myelin formation was observed. Curcumin treatment did not change the expression of ER stress markers and subcellular localization of the mutant protein in vitro and/or in vivo. Curcumin partially mitigated the clinical and pathological phenotype of msd mice, although molecular mechanisms underlying this curative effect are yet undetermined. Nonetheless, curcumin may serve as a potential therapeutic compound for PMD caused by PLP1 point mutations. (C) 2012 Elsevier Inc. All rights reserved.

We report here a 6-year-old boy exhibiting severe dystonia, profound intellectual and developmental disability with liver disease, and sensorineural deafness. A deficient creatine peak in brain H-1-MR spectroscopy and high ratio of creatine/creatinine concentration in his urine lead us to suspect a creatine transporter (solute carrier family 6, member 8; SLC6A8) deficiency, which was confirmed by the inability to take up creatine into fibroblasts. We found a large similar to 19 kb deletion encompassing exons 5-13 of SLC6A8 and exons 5-8 of the B-cell receptor-associated protein (BAP31) gene. This case is the first report in which the SLC6A8 and BAP31 genes are both deleted. The phenotype of BAP31 mutations has been reported only as a part of Xq28 deletion syndrome or contiguous: ATP-binding cassette, sub-family D, member 1 (ABCD1)/DXS1375E (BAP31) deletion syndrome [MIM ID #300475], where liver dysfunction and sensorineural deafness have been suggested to be attributed to the loss of function of BAP31. Our case supports the idea that the loss of BAP31 is related to liver dysfunction and hearing loss. (C) 2012 Elsevier Inc. All rights reserved.

The changes in the signals for brain metabolites in the left cerebellum of a 14-year-old boy with acute hemicerebellitis were monitored using proton magnetic resonance spectroscopy (MRS). From the onset of disease treatment to long-term follow-up, MRS data were serially acquired from the left and right cerebella, basal ganglia (BG), and centrum semiovale (CS). Large fluctuations in his MRS signals were observed in the left cerebellum. At onset (first day), his glutamate/glutamine complex signals were increased (>mean +/- 2 standard deviations [SD] of the control), and those for N-acetylaspartate/N-acetylaspartylglutamate and myo-inositol were decreased (<2SD). By the 25th day, these signals had recovered to normal levels, while those for choline (Cho) were increased. In other locations, the signals for mins in the BG and Cho in the CS were decreased on the seventh day. By the 201st day, the levels of all metabolites in all locations had recovered to within +/- 2SD of the control levels. In vivo proton MRS monitoring demonstrated reversible metabolite changes associated with acute hemicerebellitis, which should contribute to its differential diagnosis from brain tumors.

Nonketotic hyperglycinemia (NKH), or glycine encephalopathy, is an autosomal recessive disorder caused by a defect in the glycine cleavage enzyme system. In neonatal-onset NKH, patients manifest lethargy, hypotonia, apnea, and intractable epileptic seizures that are not specific to this disease. We experienced a 6-year-old girl with spastic quadriplegia, intractable epilepsy, and mental retardation, all initially regarded as sequelae of neonatal meningitis. The seizure frequency was transiently increased when valproate was started. Head MRI revealed progressive brain atrophy and white matter loss with high intensity signals on T2-weighted and diffusion-weighted images, which prompted us to conduct further metabolic workups. High glycine levels led us to suspect NKH, and we confirmed this diagnosis by the non-invasive, C-13-glycine breath test. DNA sequencing revealed novel Leu885Pro/Trp897Cys mutations in the glycine decarboxylase gene that were transmitted from both parents. Sodium benzoate and dextromethorphan dramatically decreased her hypertonicity. Our case shows that paradoxical increases in seizure frequency following valproate can be a clue for a diagnosis of NKH, and that a correct diagnosis of NKH can greatly alter the quality of life in such patients. (C) 2011 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

We report on a female patient with early infantile epileptic encephalopathy and severe psychomotor disability possessing a de novo balanced translocation t(1;9)(q32;q13). The patient showed clonic convulsions of extremities 2 days after birth. Electroencephalogram (EEG) transiently showed atypical suppression-burst pattern. The seizures evolved to brief tonic spasms, and hypsarrhythmia on EEG was noticed at age of 5 months, indicating the transition to West syndrome. By using fluorescent in situ hybridization (FISH), southern hybridization, and inverse PCR, the translocation breakpoints were successfully determined at the nucleotide level. The 1q32.1 breakpoint was located within a segmental duplication and disrupted the gene encoding Slit-Robo Rho GTPase activating protein 2 (SRGAP2). The 9q13 breakpoint was suggested to reside in the heterochromatin region. Srgap2 has been shown to be specifically expressed in developing brain of rodents, negatively regulate neuronal migration and induce neurite outgrowth and branching. Thus, SRGAP2 is very likely to play a role in the developing human brain. This is a first report of the SRGAP2 abnormality associated with early infantile epileptic encephalopathy. (C) 2011 Wiley Periodicals, Inc.

We report 12 cases of acute encephalopathy associated with influenza H1N1-2009 treated according to Japanese guideline (2009). In all 12 cases, electroencephalogram presented diffuse or localized high-amplitude slow waves. Brain CT and MRI showed abnormalities in 4 and 6 cases, respectively. We used hypothermia therapy for 5 patients. One patient showed impairment in short term memory, while the rest of the patients showed no sequelae. These 12 cases presented here suggest the early recognition and therapy according to the newly proposed guideline may reduce severe sequelae and mortality by acute encephalopathy associated with influenza H1N1-2009.

Congenital hypomyelinating disorders are a heterogeneous group of inherited leukoencephalopathies characterized by abnormal myelin formation. We have recently reported a hypomyelinating syndrome characterized by diffuse cerebral hypomyelination with cerebellar atrophy and hypoplasia of the corpus callosum (HCAHC). We performed whole-exome sequencing of three unrelated individuals with HCAHC and identified compound heterozygous mutations in POLR3B in two individuals. The mutations include a nonsense mutation, a splice-site mutation, and two missense mutations at evolutionally conserved amino acids. Using reverse transcription-PCR and sequencing, we demonstrated that the splice-site mutation caused deletion of exon 18 from POLR3B mRNA and that the transcript harboring the nonsense mutation underwent nonsense-mediated mRNA decay. We also identified compound heterozygous missense mutations in POLR3A in the remaining individual. POLR3A and POLR3B encode the largest and second largest subunits of RNA Polymerase III (Pol III), RPC1 and RPC2, respectively. RPC1 and RPC2 together form the active center of the polymerase and contribute to the catalytic activity of the polymerase. Pol III is involved in the transcription of small noncoding RNAs, such as SS ribosomal RNA and all transfer RNAs (tRNA). We hypothesize that perturbation of Pal 111 target transcription, especially of tRNAs, could be a common pathological mechanism underlying POLR3A and POLR3B mutations.

Congenital cerebral hypomyelination includes a group of genetic disorders, such as Pelizaeus-Merzbacher disease (PMD), and is characterized by hypomyelination of the cerebral white matter. Until recently, no classification system was available for congenital hypomyelination disorders that are clinically and genetically excluded for PMD. However, the establishment of new disease entities with gene discoveries has generated a clinical need for a new classification and diagnostic criteria for this group of disorders. Here, we review the recent findings on congenital cerebral hypomyelination, which includes 11 diseases, with a novel disease classification and diagnostic criteria with flow charts.

Background Conventional PCR-based direct sequencing of candidate genes for a family with X-linked leucoencephalopathy with unknown aetiology failed to identify any causative mutations. Objective To carry out exome sequencing of entire transcripts of the whole X chromosome to investigate a family with X linked leucoencephalopathy. Methods and results Next-generation sequencing of all the transcripts of the X chromosome, after liquid-based genome partitioning, was performed on one of the two affected male subjects (the proband) and an unaffected male subject (his brother). A nonsense mutation in MCT8 (c.1102A -> T (p. R368X)) was identified in the proband. Subsequent PCR-based direct sequencing of other family members confirmed the presence of this mutation, hemizygous in the other affected brother and heterozygous in the proband's mother and maternal grandmother. MCT8 mutations usually cause abnormal thyroid function in addition to neurological abnormalities, but this proband had normal thyroid function. Conclusion Single-lane exome next-generation sequencing is sufficient to fully analyse all the transcripts of the X chromosome. This method is particularly suitable for mutation screening of X-linked recessive disorders and can avoid biases in candidate gene choice.

We investigated seizure, intelligence quotient (IQ), and neurological outcomes including the process of motor function recovery after functional right hemispherectomy in 3 children with Rasmussen's encephalitis (RE). Before the procedure, they were unable to walk, nor sit without support due to progressive worsening of left hemiplegia and relentless epilepsia partialis continua (EPC) of the left extremities, which were refractory to antiepileptic drug and immunological treatment. After functional right hemispherectomy, EPC completely disappeared, although complete left hemiplegia was sustained. However, they recovered up to being able to walk independently with assistance devices, and to have an ordinary life with family support within 1.5 to 5 months through rehabilitation. At the same time, the interictal EEG improved on the unaffected side of hemisphere, exhibiting a posterior alpha rhythm. Their IQ also improved, and they were able to attend school. Early functional hemispherectomy should be considered before patients with RE are left in a serious condition due to progressive worsening of hemiplegia and seizures refractory to the available treatment.

We report acute encephalopathy in two cases with severe congenital hydrocephalus. Case 1 was a 23-month-old girl, born at of 36 weeks gestation and delivered by cesarean section due to congenital hydrocephalus. Magnetic resonance imaging (MRI) showed prominent ventricular dilation associated with hydrocephalus, Dandy Walker variant and cortical malformation. The blood test for toxoplasmosis, syphilis, varicella-zoster, rubella, cytomegalovirus, and herpes simplex virus (TORCH) complex and various metabolic tests of blood and urine specimens yielded unremarkable results. She was admitted to our hospital for respiratory failure with fever and her clinical course deteriorated, progressing to hemiconvulsion hemiplegia epilepsy syndrome. Case 2 was a 17-month-old boy, born by spontaneous vertex delivery at 39 weeks. Severe, asymmetrical ventricular dilation associated with hydrocephalus, cerebellar and brainstem hypoplasia, and punctuate calcifications of the thalamus, third and fourth ventricles, around the aqueduct, were observed on computed tomography (CT). The blood test for TORCH complex and various metabolic tests of blood and urine specimens yielded unremarkable results. He was admitted to our hospital for status epilepticus with fever and his clinical course progressed to hemorrhagic shock and encephalopathy syndrome. In patients with brain disorders, diagnosis and treatment are likely to be delayed and prognosis may thereby be worsened. When status epileptics or prolonged coma manifests even in patients with severe brain disorders, we must consider encephalopathy in the differential diagnosis. (C) 2010 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

【目的】意思疎通の困難な小児神経疾患の急性呼吸不全に対するMechanically Assisted Coughing(MAC)の有効性と安全性を明らかにする。【対象】日常でMACを使用していない意思疎通困難な神経疾患児のうち、平成22年2月から5月に急性呼吸不全に対してMACを使用した当院に入院した症例を対象とした。【方法】診療録からの後方視的検討。MAC導入3日以内にPaCO2が20mmHg以上改善、SpO2≧95%となる酸素必要量の減少、P/F比100以上改善、5日以内に無気肺消失を認めた症例を有効、喀出量が増えたが有効と判定できない症例を境界、それ以外を無効として検討した。【結果】10例11回の入院でMACが施行された(0.2-20.4歳、中央値1.8歳)。autoモードで陽圧:陰圧:休止=1:1:2秒、圧±20-30cmH2Oで5呼吸を3-10サイクル、一日1-4セット施行した。有効5回、無効3回、境界3回であった。気胸や不整脈のような合併症は生じなかった。【結論】MACは意思疎通の困難な児の急性呼吸不全にも有効な例があり、安全に施行できることが分かった。(著者抄録)

A 19-year-old university student with no personal or family history of neurologic disorders developed convulsions and was administered phenytoin. Two months later, he developed lower limb-dominant acute demyelinating polyneuropathy, from which he recovered within 2 months. At age 20, he rapidly developed visual disturbances and paraplegia from phenytoin intoxication. Cranial magnetic resonance imaging (MRI) revealed leukoencephalopathy with no evidence of thrombosis or vasoconstriction. Hyperhomocysteinemia, hypomethioninemia, low serum folate concentration, and an absence of megaloblastic anemia were consistent with the diagnosis of methylenetetrahydrofolate reductase (MTHFR) deficiency. A genomic DNA sequence analysis demonstrated compound heterozygosity for two missense mutations in the MTHFR gene, namely, [458G>T + 459C>T] (Gly149Val) and 358G>A (Ala116Thr), both of which are known pathogenic mutations. An absence of leukoencephalopathic changes on MRI scans performed 9 months previously strongly suggested that phenytoin intoxication caused acute leukoencephalopathy. Therefore, phenytoin may be an aggravating factor of remethylation defects in patients with MTHFR deficiency.

5,10-Methylenetetrahydrofolate reductase (MTHFR) deficiency is the most prevalent inborn error of folate metabolism, and has variable clinical manifestations from asymptomatic to severe psychomotor retardation, microcephalus and seizure. In untreated infantile cases, it predominantly affects the central nervous system, which is sometimes fatal. On the other hand, peripheral nerve involvement is uncommon. We present a severe infantile case of MTHFR deficiency that manifested unilateral phrenic nerve palsy with communicating hydrocephalus, developmental delay and died at 11 months of age. An enzymatic study confirmed MTHFR deficiency with residual activity of 0.75% of mean control values in cultured fibroblasts. Mutation analysis of the MTHFR gene revealed homozygous, tandem missense mutations c.[446G > T; 447C > T] in exon 3 of the MTHFR gene converting glycine to valine (Gly149Val). In MTHFR deficiency, betaine may improve the symptoms if started immediately after birth by reducing the level of serum homocysteine and increasing that of methionine. Our results show that we should be aware of possible inborn errors of folate metabolism such as MTHFR deficiency, in infants with unexplained developmental delay manifesting rapidly progressive polyneuropathy. (C) 2010 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

5歳女児。1病日に左足を引きずり歩行障害が出現し、時折静止できずに立位・座位困難となった。24病日頃より不眠が出現し、歩行障害のためずり這いをするようになった。構音障害、食事摂取量の低下、睡眠障害が次第に増悪し48病日に転院した。自己免疫性疾患の可能性を考え免疫療法を考慮した。54病日に1回目のステロイドパルス療法を施行し右上肢の舞踏病様運動と舌のジスキネジアが改善した。しかし、徐々に発語が消失し疎通性と自発性が低下し、68病日には疎通性が消失し痛み刺激に反応なく、体幹を前後左右に倒しては起き上がるという常同運動が出現した。75病日から免疫グロブリン療法を開始し、常同運動の著しい改善がみられ、疎通性も徐々に改善した。自立歩行も可能となり104病日に退院した。髄液抗NMDA受容体抗体が陽性であること、臨床経過とあわせて抗NMDA受容体脳炎と診断した。

Dravet syndrome (severe myoclonic epilepsy in infancy) is an epileptic syndrome with various types of seizures that begin in the first year of life and may result in intellectual impairment. Mutations of the SCN1A gene are the most prevalent genetic cause of Dravet syndrome. In this study, we report a 12-year-old girl with Dravet syndrome carrying an SCN1A mutation, c.2785Cdel (L929del fsX934). She had an episode of status epilepticus and persistent lethargy after 48h of acute febrile illness that was preceded by an annual flu vaccination. Low voltage activities detected by electroencephalogram and elevated neuron-specific enolase/interleukin-6 concentrations in the cerebrospinal fluid suggested acute encephalopathy. MRI showed abnormalities in the bilateral thalami, cerebellum and brainstem. These abnormalities were protracted over a month. The biochemical and MRI characteristics of this case are different from any known type of encephalopathy, and may suggest a vulnerability of neurons expressing mutant SCN1A in the brain. © Georg Thieme Verlag KG Stuttgart New York.

Hypomyelination with hypogonadotropic hypogonadism and hypodontia (4H syndrome) is a rare disease, characterized by both central and peripheral hypomyelination. We describe a 21-year-old male with mildly progressive ataxia, mental retardation, pituitary hypogonadotropic hypogonadism, delayed dentition, and cataract. Brain magnetic resonance imaging showed hypomyelinated white matter, cerebellar atrophy, and a thin corpus callosum. The literature suggests that abnormal findings upon sural nerve biopsy may indicate peripheral hypomyelination, even in the absence of clinically and physiologically evident peripheral neuropathy. A sural nerve biopsy of this patient was normal, and this finding is further discussed. Taken together with previous reports, this case suggests that 4H syndrome can be regarded as a spectrum disorder, the cardinal signs of which may be central hypomyelination, ataxia, hypogonadotropic hypogonadism, and hypodontia. (C) 2010 Elsevier B.V. All rights reserved.