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Ral (Ras-like) GTPases play an important role in the control of cell migration and have been implicated in Ras-mediated tumorigenicity. Recently, variants in RALA were also described as a cause of intellectual disability and developmental delay, indicating the relevance of this pathway to neuropediatric diseases. Here, we report the identification of bi-allelic variants in RALGAPA1 (encoding Ral GTPase activating protein catalytic alpha subunit 1) in four unrelated individuals with profound neurodevelopmental disability, muscular hypotonia, feeding abnormalities, recurrent fever episodes, and infantile spasms . Dysplasia of corpus callosum with focal thinning of the posterior part and characteristic facial features appeared to be unifying findings. RalGAPA1 was absent in the fibroblasts derived from two affected individuals suggesting a loss-of-function effect of the RALGAPA1 variants. Consequently, RalA activity was increased in these cell lines, which is in keeping with the idea that RalGAPA1 deficiency causes a constitutive activation of RalA. Additionally, levels of RalGAPB, a scaffolding subunit of the RalGAP complex, were dramatically reduced, indicating a dysfunctional RalGAP complex. Moreover, RalGAPA1 deficiency clearly increased cell-surface levels of lipid raft components in detached fibroblasts, which might indicate that anchorage-dependence of cell growth signaling is disturbed. Our findings indicate that the dysregulation of the RalA pathway has an important impact on neuronal function and brain development. In light of the partially overlapping phenotype between RALA- and RALGAPA1-associated diseases, it appears likely that dysregulation of the RalA signaling pathway leads to a distinct group of genetic syndromes that we suggest could be named RALopathies.

Kagami-Ogata syndrome (KOS) is a rare genomic imprinting disorder of chromosome 14 with characteristic facial features, a small, bell-shaped thorax, muscular hypotonia, and abdominal wall defects. We present a case of a kidney incarcerated in a posterolateral Bochdalek type congenital diaphragmatic hernia (CDH), intestinal malrotation and stage 2 rectocele in KOS. Successful repair of CDH and malrotation was achieved with Ladd's procedure, CDH repair, Nissen fundoplication and gastrostomy tube placement. She had no post-operative complications and is currently tolerating 100% enteral feeds. CDH, intestinal malrotation and rectocele have not been previously reported in KOS. Despite overall poor prognosis, KOS patients with CDH and malrotation can be repaired successfully with improvement in quality of life.

Arthrogryposis multiplex congenital, the occurrence of multiple joint contractures at birth, can in some cases be accompanied by insufficient myelination of peripheral nerves, muscular hypotonia, reduced tendon reflexes, and respiratory insufficiency. Recently mutations in the CASPR/CNTN1 complex have been associated with similar severe phenotypes and CNTNAP1 gene mutations, causing loss of the CASPR protein, were shown to cause severe, prenatal onset arthrogryposis multiplex congenita in four unrelated families. Here we report a consanguineous Arab family from Qatar with three children having an early lethal form of arthrogryposis multiplex congenita and a novel frameshift mutation in CNTNAP1. We further expand the existing CNTNAP1-associated phenotype to include profound cerebral and cerebellar atrophy.

The prevalence of obstructive sleep apnea-hypopnea syndrome in the general childhood population is 1-2% and the most common cause is adenotonsillar hypertrophy. However, beyond adenotonsillar hypertrophy, there are other highly prevalent causes of this syndrome in children. The causes are often multifactorial and include muscular hypotonia, dentofacial abnormalities, soft tissue hypertrophy of the airway, and neurological disorders). Collaboration between different specialties involved in the care of these children is essential, given the wide variability of conditions and how frequently different factors are involved in their genesis, as well as the different treatments to be applied. We carried out a wide literature review of other causes of obstructive sleep apnea-hypopnea syndrome in children, beyond adenotonsillar hypertrophy. We organised the prevalence of this syndrome in each pathology and the reasons that cause it, as well as their interactions and management, in a consistent manner.

Background The kyphoscoliotic type of the Ehlers-Danlos syndrome is an autosomal recessive connective tissue disorder characterized by soft extensible skin, laxity of joints, severe muscle hypotonia at birth, and kyphoscoliosis. Patient We describe a 3-year-old girl with the kyphoscoliotic type of the Ehlers-Danlos syndrome whose parents were cousins. She was born with breech presentation by vaginal delivery at term after a normal pregnancy. At birth she manifested hypotonia and congenital kyphosis. On the second postnatal day, subdural and intraparenchymal hemorrhages were detected by magnetic resonance imaging. During follow-up at 18 months of age, strabismus, umbilical hernia, kyphoscoliosis, joint laxity, bilateral hip dislocation, muscular hypotonia, and motor developmental delay. Results The cranial magnetic resonance imaging revealed periventricular leukomalacia and abnormal signal related to previous hemorrhage. Metabolic investigations and neuromuscular evaluation were normal, excluding other possible explanations of hypotonia. An analysis of urinary cross-links demonstrated an increase in the lysyl-pyridinoline to hydroxylysyl-pyridinoline ratio, suggesting the diagnosis of kyphoscoliotic type of the Ehlers-Danlos syndrome. Molecular analysis of the PLOD1 gene revealed that she had a novel homozygous p.Pro622Argfs*3 (c. 1863_1864dupCG) mutation in exon 17 that is expected to cause complete loss of the enzyme lysyl hydroxylase 1 and to cause kyphoscoliotic type of the Ehlers-Danlos syndrome. Conclusions We describe a child with the kyphoscoliotic type of the Ehlers-Danlos syndrome with a novel mutation of the PLOD1 gene. Our observations suggest that vascular lesions in the neonatal period may be a rare additional clinical feature of kyphoscoliotic type of the Ehlers-Danlos syndrome.

Prader-Willi syndrome (PWS) is caused by the lack of paternal expression of imprinted genes in the human chromosomal region 15q11.2-q13.2, which can be due to an interstitial deletion at 15q11.2-q13 of paternal origin (65-75%), maternal uniparental disomy (matUPD) of chromosome 15 (20-30%), or an imprinting defect (1-3%). The majority of PWS-associated matUPD15 cases represent a complete heterodisomy of chromosome 15 or a mixture of hetero- and isodisomic regions across the chromosome 15. Pure maternal isodisomy is observed in only a few matUPD15 patients. Here we report a case of an 18-year-old boy with some clinical features of Prader-Willi syndrome, such as overweight, muscular hypotonia, facial dysmorphism and psychiatric problems, but there was no reason to suspect PWS in the patient based solely on the phenotype estimation. However, chromosomal microarray analysis (CMA) revealed mosaic loss of heterozygosity of the entire chromosome 15. Methylation-specific multiplex ligation-dependant probe amplification (MS-MLPA) analysis showed hypermethylation of the SNRPN and NDN genes in the PWS/AS critical region of chromosome 15 in this patient. Taking into consideration the MS-MLPA results and the presence of PWS features in the patient, we concluded that it was matUPD15, although the patient's parents were not enrolled in the study. According to CMA and karyotyping, no trisomic or monosomic cells were present. To the best of our knowledge, only two PWS cases with mosaic maternal isodisomy 15 and without trisomic/monosomic cell lines have been reported so far.

We report on a de novo interstitial del/dup aberration consisting of a 13.3 Mb deletion of 5q15-5q21.3 (92.1-105.4 Mb, hg19) and a 23.6 Mb tandem direct duplication of 5q21.3-5q23.3 (106.1-129.7 Mb, hg19). Although the aberration covered a total of 60.6 Mb, it was cryptic, i.e., not detectable by karyotyping at a resolution of 430 bands. Array-CGH indicated a diploid region of 0.6 Mb between the duplicated and the deleted segment. The aberration affected a 14-month-old boy conceived after intracytoplasmic sperm injection who presented with developmental delay, muscular hypotonia, partial agenesis of the corpus callosum, prominent forehead, low set ears, hypertelorism, hyperopia, wide-bridged nose, retrognathia, high palate, and cryptorchidism. The duplicated segment comprised the LMNB1 gene, thus predicting adult-onset autosomal-dominant leukodystrophy and revealing a temporal dimension of the phenotype. Counseling problems implicated by this prediction include "the right not to know" that the patient might want to exercise when coming of age.

Congenital disorders of glycosylation (CDG) are caused by enzymatic defects of the formation or processing of lipid-linked oligosaccharides and glycoproteins. Since the majority of proteins is glycosylated, a defect in a singular CDG enzyme leads to a multisytemic disease with secondary malfunction of thousands of proteins. CDG-Ij (DPAGT1-CDG) is caused by a defect of the human DPAGT1 (UDP-GlcNAc: Dolichol Phosphate N-Acetylglucosamine-1-Phosphotransferase), catalyzing the first step of N-linked glycosylation. So far the clinical phenotype of only one CDG-Ij patient has been described. The patient showed severe muscular hypotonia, intractable seizures, developmental delay, mental retardation, microcephaly and exotropia. Molecular studies of this patient revealed the heterozygous mutation c.660A > G (Y170C; paternal) in combination with an uncharacterized splicing defect (maternal). Two further mutations, c.890A > T (I297F) and c.162-8 G > A as a splicing defect were detected when analyzing DPAGT1 in two affected siblings of a second family. We report two new patients with the novel homozygous mutation, c.341 C > G (A114G), causing a severe clinical phenotype, characterized by hyperexcitability, intractable seizures, bilateral cataracts, progressive microcephaly and muscular hypotonia. Both our patients died within their first year of life. With the discovery of this novel mutation and a detailed clinical description we extend the clinical features of CDG-Ij in order to improve early detection of this disease.

In a family three children presented with severe neonatal lactic acidosis, hypertrophic cardiomyopathy and generalised muscular hypotonia. One child died in infancy, two survived a clinically severe neonatal period. At an age of 9 and 17years, respectively, they present with exercise intolerance, proximal muscle weakness, non-progressive hypertrophic cardiomyopathy and normal mental development. In a muscle biopsy normal activity of respiratory chain enzymes was found; however the amount of the mitochondrial phosphate carrier was decreased. This protein is expressed in two tissue-specific isoforms generated by mutually exclusive alternative splicing of the SLC25A3 gene transcript. We identified a homozygous mutation c.158-9A>G located in the 5'-intron next to exon 3A specific for heart and skeletal muscle. This creates a novel splice site resulting in a more than 95% decrease of the wild type allele.

The heterozygous 15q13.3 microdeletion syndrome (MIM #612001) was first described by Sharp et al. in 2008. So far four patients with 15q13.3 homozygous or compound heterozygous microdeletions have been identified. Here we report a non-consanguineous family with two affected siblings carrying a homozygous microdeletion of ∼1.5 Mb at the 15q13.3 locus. They presented with congenital retinal dysfunction, refractory epilepsy, encephalopathy, mental retardation, repetitive hand movements, severe muscular hypotonia and macrocytosis. Dysmorphic facial features are synophrys and bilateral proptosis. The siblings carry a homozygous microdeletion at 15q13.3 of ∼1.5 Mb including the genes ARHGAP11B, MTMR15, MTMR10, TRPM1, KLF13, OTUD7A, and CHRNA7. The absence of CHRNA7 has been suggested as a cause of refractory seizures. According to knock-out experiments the deletion of KLF13 could be an explanation for macrocytosis. The homozygous loss of TRPM1 could be a possible explanation for congenital retinal dysfunction.

To date, more than 100 cases with a deletion of chromosome 2q have been identified, although studies reporting small interstitial deletions involving the 2q24.2-q24.3 region are still rare. Here, we have described the genotype and the phenotype of a boy with a 5.3 Mb de novo deletion in this region, identified by SNP array analysis. The selected region included 20 genes, of which 4 are prominently expressed in the brain. Their combined haplo-insufficiency could explain the main clinical features of this patient which included mental retardation, severe hypotonia, joint laxity and mild dysmorphic traits.

Prader-Willi syndrome (PWS) and Ehlers-Danlos syndrome (EDS) are two different genetical disorders both characterized, among other features, by muscular hypotonia. Postural control seems to be impaired in both conditions. The aim of the present study was to quantitatively compare postural control in adult PWS and EDS using stabilometric platform to unveil possible common determinants of impaired balance. We enrolled 11 PWS and 21 EDS adult patients and 20 age-matched controls. They were instructed to maintain an upright standing position for 30s with open eyes (OEs) focusing on a 6 cm black circle positioned at a distance of 1.5m. Both PWS and EDS patients were characterized by higher RANGEML, RANGEAP and trajectory length of CoP values as compared to CG. No statistically differences were found between PWS and EDS in terms of any of these parameters. The results demonstrated that both PWS and EDS are characterized by a severe postural instability. Muscle hypotonia and weakness may account for reduced balance capacity. Quantitative characterization of instability is important to identify, develop and enhance rehabilitation interventions.

Nonketotic hyperglycinemia (OMIM #605899), also known as glycine encephalopathy, is an autosomal recessive disorder of glycine metabolism caused by a defect in the glycine cleavage system. A term neonate developed progressive lethargy, muscular hypotonia, and respiratory insufficiency on day 2 after birth, but no overt clinical seizures. Amplitude-integrated electroencephalography indicated a continuous burst-suppression pattern. The diagnosis of nonketotic hyperglycinemia was made biochemically and was confirmed by genetic studies, which revealed two missense mutations (one not previously described) within the glycine decarboxylase gene, GLDC. Nonketotic hyperglycinemia should be incorporated into the differential diagnosis of neonatal hypotonia, to avoid an erroneous diagnosis of sepsis or hypoxic ischemic injury. Amplitude-integrated electroencephalography may be helpful in the initial assessment of severely sick and hypotonic neonates without overt clinical seizures, and may direct further diagnostic evaluation.

Congenital disorders of glycosylation (CDG) are an expanding group of inherited disorders caused by defects in the N- or O-Glycosylation of proteins and lipids. Several CDG subtypes have been described so far, including CDG type Ih which is caused by a deficiency of the dolichyl-P-Glc:Glc(1)Man(9)GlcNAc(2)-PP-dolichyl alpha1,3-glucosyltransferase (hALG8). The defect leads to an accumulation of Dol-PP-GlcNAc(2)Man(9) and Dol-PP-GlcNAc(2)Man(9)Glc(1) in the endoplasmic reticulum of patients' fibroblasts that can be detected by analyzing the lipid-linked oligosaccharyl intermediates. Five patients with CDG-Ih have been described so far. The clinical presentation of four of these patients was severe with death in early infancy. In this report, we describe two mildly affected siblings with CDG-Ih caused by two novel mutations. While one mutation (c.1434delC) causes a frame shift resulting in a premature termination codon (p.485X), the point mutation of the other allele (c.845C>T, p.A282V) causes an amino acid replacement in a highly conserved region of the hALG8 gene. The two siblings show similar symptoms, including pseudo-gynecomastia, epicanthus, muscular hypotonia, mental retardation and ataxia, expanding the genetic and clinical spectrum of CDG-Ih.

Diploid/triploid mosaicism is a rare chromosome aberration characterized by growth and mental retardation, muscular hypotonia, clinodactyly, syndactyly of fingers and toes, asymmetry of the body and the face, truncal obesity, and pigmentary anomalies of the skin. Many patients initially present with severe growth retardation and develop truncal obesity later in life. Variable phenotype expression during development and restriction of triploid cells to certain tissues explain why the diagnosis of diploid/triploid mosaicism is often delayed. Here, we report on a moderately retarded 14-year-old girl with diploid/triploid mosaicism due to inclusion of the second polar body, whose changing phenotype overlaps considerably with different genetic disorders associated with aberrant genomic imprinting. The observation that triploid cells, which in our patient show remarkably variable distribution in different tissues, may also be present in easily accessible tissues such as urinary sediment or buccal smear may contribute to an earlier diagnosis of this rare syndrome.

Monosomy 1p36 is one of the most commonly observed mental retardation (MR) syndromes that results in a clinically recognizable phenotype including delayed psychomotor development and/or MR, hypotonia, epilepsy, hearing loss, growth delay, microcephaly, deep-set eyes, flat nasal bridge and pointed chin. Besides, a Prader-Willi syndrome (PWS)-like phenotype has been described in patients with 1p36 monosomy. Forty-one patients presenting hypotonia, developmental delay, obesity and/or hyperphagia and behavioral problems who tested negative for PWS were investigated by FISH and/or microsatellite markers. Twenty-six were analyzed with a 1p-specific subtelomeric probe, and one terminal deletion was identified. Thirty patients (15 of which also studied by FISH) were investigated by microsatellite markers, and no interstitial 1p36 deletion was found. Our patient presenting the 1p36 deletion did not have the striking features of this monosomy, but her clinical and behavioral features were quite similar to those observed in patients with PWS, except for the presence of normal sucking at birth. The extent of the deletion could be limited to the most terminal 2.5 Mb of 1p36, within the chromosomal region 1p36.33-1p36.32, that is smaller than usually seen in monosomy 1p36 patients. Therefore, chromosome 1p36.33 deletion should be investigated in patients with hypotonia, developmental delay, obesity and/or hyperphagia and behavioral problems who test negative for PWS.

Summary Aims This study attempts to determine the type and relative frequency of muscle diseases contributing to floppy and hypotonic infants in Singapore. Methods Eighty consecutive muscle biopsies in the Department of Pathology, National University of Singapore, in the period 1978–2000, in which a clinical diagnosis of floppy or hypotonic infant was made, were reviewed. Results The commonest cause of severe hypotonia in infancy was spinal muscular atrophy, which accounted for 33% of cases followed by congenital muscular dystrophy (13%). Eight cases (10%) of infantile type II glycogenosis (Pompe’s disease) were encountered. There were seven cases of congenital myopathy, of which four were centronuclear myopathy, and one each of central core myopathy, nemaline myopathy and congenital fibre type disproportion. One case of centronuclear myopathy was associated with type I fibre smallness. Type II atrophy, which is generally considered a non-specific change, was encountered in five cases. Of interest is the relatively large number of muscle biopsies (29%) in which no significant pathological features were encountered at the light microscopic, histochemical as well as ultra-structural level. Conclusions The study has revealed a great variety of pathology affecting the muscle of children presenting as floppy infants or with hypotonia. The muscle diseases included spinal muscular atrophy, congenital muscular dystrophies, congenital myopathies and metabolic myopathies. However, 23 (29%) cases showed no significant pathology. For this group of floppy and hypotonic infants further studies are needed.

The floppy infant syndrome is a well-recognized entity for pediatricians and neonatologists. The condition refers to an infant with generalized hypotonia presenting at birth or in early life. The diagnostic work up in many instances is often complex, and requires multidisciplinary assessment. Advances in genetics and neurosciences have lead to recognition of newer diagnostic entities (several congenital myopathies), and rapid molecular diagnosis is now possible for several conditions such as spinal muscular atrophy (SMA), congenital muscular dystrophies (CMD), several forms of congenital myopathies and congenital myotonic dystrophy. The focus of the present review is to describe the advances in our understanding in the genetic, metabolic basis of neurological disorders, as well as the investigative work up of the floppy infant. An algorithm for the systematic evaluation of infants with hypotonia is suggested for the practicing pediatrician/neonatologist.

Congenital hypotonia with favorable outcome is characterized by an early neonatal onset and a benign clinical course. The old term, proposed by Walton, was benign congenital hypotonia, denoting the presence of muscle weakness and hypotonia, with the exception of Werdnig-Hoffmann disease. It has been clear that this term includes congenital myopathies with definite changes in the muscle fiber. However, many cases remain unclarified. The term congenital hypotonia with favorable outcome includes only these last cases. A long-term follow-up study of children with congenital hypotonia with favorable outcome is presented, and a hypothetical mechanism underlying muscle shortening is discussed. The study was carried out at the Department of Child Neuropsychiatric Sciences, University "La Sapienza" of Rome, during the period 1985-2000, and included 41 patients with congenital hypotonia. Our study confirms the good prognosis of congenital hypotonia with favorable outcome and suggests a correlation with joint hyperlaxity, which is observed in many parents of our children, as if the latter developed from the former. On the basis of experimental changes occurring in the muscles, we believe that in our cohort the main cause of shortening is caused by an increase in joint mobility, which keeps muscles shortened in both the passive and active states for a long time. If this view is confirmed by other studies, we suggest continuous muscle exercise as a preventive treatment.

The aim of this study was to determine the efficacy and safety of intrathecal baclofen (ITB) delivered by a programmable pump for the chronic treatment of severe spasticity due to traumatic brain injury (TBI). Eight patients with severe spasticity following TBI, refractory to oral baclofen or who experienced intolerable side effects, were screened. The first five patients were enrolled in a research protocol that was approved by the Institutional Review Board for Human Research at Boston University Medical Center. The other three patients were evaluated after the FDA approved the therapy for spasticity of cerebral origin. Results showed that the mean Ashworth score for rigidity in the legs decreased from 4.4 preoperatively to 1.3 (p < 0.05) on ITB. In the arms, the Ashworth score decreased from 2.7 to 1.5 (p < 0.05). Reduction of spasticity resulted in improved levels of physical activity and locomotion and ease of care. Complications consisted of muscular hypotonia, areflexic bladder and urinary retention, erythema, and breakdown of the skin over the pump. Our results suggest that long-term intrathecal baclofen by an implanted programmable pump is a safe and effective method of treating severe intractable spasticity arising from traumatic brain injury.

This self-directed learning module highlights hypotonia, facioscapulohumeral dystrophy, and herbal supplements causing muscle weakness. It is part of the chapter on neuromuscular rehabilitation and electrodiagnosis in the Self-Directed Physiatric Education Program for practitioners and trainees in physical medicine and rehabilitation. This section presents advances in the diagnosis of myotubular dystrophy, myoblast transfer, and problems associated with the increased use of herbal supplements.

Abnormalities of deep cerebellar nuclei in Joubert syndrome have been previously reported only in rare autopsy cases. Epilepsy in association with Joubert syndrome is also rarely reported. In two new cases of patients with Joubert syndrome, bilateral hypoplasia of deep cerebellar nuclei was detected in vivo by magnetic resonance imaging. One of the patients had drug-resistant epilepsy. Both patients received clinical examination, electroencephalography, neuropsychologic testing, and high-resolution magnetic resonance imaging (1.5 T). Patient 1, a 7-year-old boy, had muscular hypotonia, periodic tachypnea, mild ataxia, global developmental delay, exotropia, and polydactyly. Patient 2, a 23-year-old woman, had muscular hypotonia, epilepsy with pharmacoresistant generalized tonic-clonic seizures, learning disability, esotropia, and mild gait ataxia. Abnormalities of deep cerebellar nuclei might contribute to the pathophysiology of epilepsy in patients with Joubert syndrome.

SummaryWe describe a family with a novel disorder characterized by episodic muscle weakness and X-linked inheritance. Eight males in three generations demonstrate the characteristic features of the disorder. Episodes of severe muscle weakness are typically precipitated by febrile illness and affect the facial and extraocular musculature, as well as the trunk and limbs, and resolve spontaneously over a period of weeks to months. Younger members of the family are normal between episodes but during relapses show generalized weakness, ptosis, and fluctuations in strength. In some cases, fatigability can be demonstrated. The proband has late-onset chronic weakness and fatigability. The clinical phenotype has features suggestive both of the congenital myasthenic syndromes and of ion-channel disorders such as the periodic paralyses. We have localized the responsible gene to chromosome Xp22.3, with a maximum two-point LOD score of 4.52 at a recombination fraction of .0, between OACA2 and DXS9985.

A group of 25 children (5 months to 20 years of age) presenting with intractable seizures, developmental delay, and severe hypotonia, who did not fall into the known categories of mitochondrial encephalomyopathies, underwent muscle biopsy for evaluation of mitochondrial function and were compared with age-matched control subjects. Biopsied skeletal muscle was analyzed for six mitochondrial enzyme-specific activities, mitochondrial DNA point mutations and deletions, and mitochondrial DNA levels. The data reveal a high incidence of specific mitochondrial enzyme activity defects. Reduced activity levels were evident in complex I (11 patients), III (24 patients), IV (nine patients), and V (10 patients). Two patients also exhibited pronounced reduction in mitochondrial DNA levels (80% reduction compared with control subjects). Two patients manifested increased levels of 5-kb and 7.4-kb mitochondrial DNA deletions. Pathogenic mutations previously described in association with mitochondrial encephalomyopathies were not evident. The data suggest that mitochondrial dysfunction, including extensive defects in specific enzyme activities, may be frequently present in children with seizures, developmental delay, and hypotonia that do not fall within the known mitochondrial encephalomyopathies. These mitochondrial deficiencies can be primarily ascertained by biochemical analysis and are rarely accompanied by mitochondrial ultrastructural changes. The molecular basis of these defects, their role in these disorders, and potential treatment warrant further study.

Resume Les malpositions de la tete chez l'enfant sont le plus souvent liees a une hypotonie ou a une dystonie cervicale, generalement dans un contexte neurologique mais aussi dans le cadre plus benin du torticolis congenital. Dans ce travail, les auteurs decrivent les elements cliniques toujours indissociables des indications et des caracteristiques d'un appareillage, puis livrent leur experience en matiere d'appareillage de la tete et du cou en cas de malposition. Parmi d'autres types d'appareils plus classiques, ils decrivent leur adaptation d'une orthese serre-tete anti-effondrement deja decrite precedemment et l'orthese helicoidale asymetrique qu'ils ont mis au point pour le traitement des dystonies en rotation de la tete.

Adenylosuccinate lyase (ASL) deficiency is a defect in purine de novo synthesis pathway. The disease has variable clinical presentation involving psychomotor retardation, seizures, hypotonia, and autism. The presence of succinyladenosine and succinylaminoimidazole carboxamide riboside (SAICA riboside) in body fluids characterizes the biochemical phenotype. All cases of ASL deficiency described to date have been diagnosed in Europe. Using a high-resolution thin-layer chromatography (TLC) technique combining screening for ASL deficiency and disorders of saccharide metabolism, we found the first case of this disease in the US. The patient presented with delayed motor development and profound hypotonia. The family history and routine laboratory tests were negative. Screening for metabolic disorders detected the presence of succinyladenosine and SAICA riboside in urine. The activity of ASL in the patient's skin fibroblasts was 43% of controls (patient, mean = 1.20 nmol/min/mg of protein, s = 0.21, n = 3; controls, mean = 2.78 nmol/min/mig of protein, s = 0.61, n = 7). In a 15-month-old girl with profound hypotonia, we established the diagnosis of ASL deficiency by demonstrating succinyladenosine and SAICA riboside in urine and decreased residual activity of ASL in skin fibroblasts.

An 11-year-old girl died of a neuronal storage disorder that clinically was characterized by failure to thrive and muscular hypotonia from birth, with the subsequent evolution of motor neuron disease, epilepsy, and dementia. A wide range of metabolic disorders, including all forms of GM2 gangliosidosis, could be excluded. Electron microscopy demonstrated neuronal zebra body inclusions, and immunohistochemistry demonstrated that GM2 ganglioside was a major constituent of the storage material. We suggest that the patient died of a lysosomal storage disease that is clinically and biochemically different from Tay-Sachs disease, Sandhoff disease, and other GM2 gangliosidoses described previously. This case also further demonstrates that significant accumulation of GM2 ganglioside, which is crucial for dendritic formation, may occur in neuronal storage diseases lacking known defects in ganglioside catabolism.

BACKGROUND: To evaluate clinical, genetic, and radiologic features of our patients with muscle-eye-brain disease. METHODS: The data of patients who were diagnosed with muscle-eye-brain disease from a cohort of patients with congenital muscular dystrophy in the Division of Pediatric Neurology of Dokuz Eylul University School of Medicine and Gaziantep Children’s Hospital between 2005 and 2013 were analyzed retrospectively. RESULTS: From a cohort of 34 patients with congenital muscular dystrophy, 12 patients from 10 families were diagnosed with muscle-eyebrain disease. The mean age of the patients was 9 � 5.5 years (2-19 years). Mean serum creatine kinase value was 2485.80 � 1308.54 IU/L (700-4267 IU/L). All patients presented with muscular hypotonia at birth followed by varying degrees of spasticity and exaggerated deep tendon reflexes in later stages of life. Three patients were able to walk. The most common ophthalmologic and radiologic abnormalities were cataracts, retinal detachment, periventricular white matter abnormalities, ventriculomegaly, pontocerebellar hypoplasia, and multiple cerebellar cysts. All of the patients had mutations in the POMGNT1 gene. The most common mutation detected in 66% of patients was c.1814 G > A (p.R605H). Two novel mutations were identified. CONCLUSIONS: We suggest that muscle-eye-brain disease is a relatively common muscular dystrophy in Turkey. It should be suspected in patients with muscular hypotonia, increased creatine kinase, and structural eye and brain abnormalities. The c.1814 G > A mutation in exon 21 of the POMGNT1 gene is apparently a common mutation in the Turkish population. Individuals with this mutation show classical features of muscle-eye-brain disease, but others may exhibit a milder phenotype and retain the ability to walk independently. Congenital muscular dystrophy patients from Turkey carrying the clinical and radiologic features of muscle-eye-brain disease should be evaluated for mutations in POMGNT1 gene.

In a follow-up study of 259 floppy infants of undetermined cause in my laboratory, 11 patients were later diagnosed as having the Prader-Willi syndrome (PWS). To clarify the pathogenesis of muscle hypotonia in PWS, I examined muscle biopsies by histochemical and morphometric methods and the results were compared with those obtained from floppy infants with only mental retardation but with no other features. The histochemical abnormalities of PWS included (i) fiber size variation of both type 1 and 2 fibers, (ii) type 2 fiber atrophy, (iii) increased numbers of type 2C fibers, and (iv) decreased numbers of type 2B fiber. Although muscle hypotonia in PWS has been thought to be due to central nervous system abnormality, my findings suggest that primary muscle pathology, including muscle fiber immaturity and abnormal muscle fiber type distribution, at least in part, plays a role in muscle hypotonia and weakness.

D-2-Hydroxyglutaric aciduria was documented in a newborn who presented with seizures, hypotonia, cortical blindness, a movement disorder, and developmental delay. Her clinical presentation differs from that of patients with L-2-hydroxyglutaric aciduria and a single previously reported patient with D-2-hydroxyglutaric aciduria. Cerebrospinal fluid levels of gamma-aminobutyric acid were elevated, while biogenic amine metabolites were normal. The movement disorder in our patient and in those with L-2-hydroxyglutaric aciduria suggests involvement of the basal ganglia in the disease process. Prenatal diagnosis of an affected fetus was accomplished during a subsequent pregnancy.

Two-hundred fifty infants with high and no risk history transitory neurological findings (TNF) were examined during the first year of life. The neurological situation and the developmental progress were reconsidered in these children at 2.5–4.5 and 5–7 years of age. TNF were diagnosed mainly during the first two trimesters. Hyperirritability and asymmetries resolved to about 70% during the first half of the first year of life. In contrast, isolated central hypotonia resolved over a much longer period. No correlations of distinct types of TNF could be found with VLBW and LBW-infants, with fullterm infants, with birthweights, nor with risk factors. Children who developed spastic CP presented permanent hypertonia beside other specific neurological symptoms during the second half of the first year of life. Children with lasting non-spastic handicaps showed permanent hypotonia combined with other neurological abnormalities and symptoms of psychomotor retardation, which evolved also during the second half of the first year. From these results the question arises: which parts of TNF are essentially neurobiological findings indicating processes of transformation of the sensory motor system from non-intentional fetal to intentional motor behaviour of early infancy. TNF, then, should no longer be looked at as symptoms of pathological value only.

Three children displaying hypotonia, cardiac involvement and defects of the mitochondrial respiratory chain complexes are reported. The first case showed severe neonatal hypotonia, failure to thrive, hepatomegaly, dilation of the right cardiac cavities, profound lactic acidosis and amino aciduria. The boy died at the age of 7 weeks. In the second case hypotonia, severe cardiomyopathy, cyclic neutropenia, lactic acidosis and 3-methylglutaconic aciduria occurred. The boy died at the age of 27 months. The third case presented at the age of 16 months as an acute hypokinetic hypertrophic cardiomyopathy with transient hypotonia and mild lactic acidosis. Spontaneous clinical remission occurred. In all cases muscle biopsy was performed. Morphological studies failed to show ragged-red fibers but there was lipid storage myopathy and decreased cytochrome c oxidase activity. Biochemical studies confirmed the cytochrome c oxidase deficiency in muscle in all cases. It was associated with complex I III deficiency in case 1 and with severe deficits of all respiratory chain complexes in case 2. Post-mortem studies in case 1 indicated that complex IV was reduced in the liver but not in the heart and quantitative analysis of mtDNA revealed a depletion in muscle. Cases 1 and 2 shared some clinical features with fatal infantile myopathy associated with cytochrome c oxidase deficiency, while case 3 displayed a very unusual clinical presentation. The histochemical enzyme reaction of cytochrome c oxidase is useful for the diagnosis of mitochondrial myopathy because ragged-red fibers may be lacking. Finally, biochemical measurement of the different mitochondrial respiratory chain complexes is required because multiple defects are frequent and occasionally related to mtDNA depletion.

Six boys who all showed the combination of moderate-severe mental retardation, autistic behavior, and mild-moderate physical stigmatization are described. Muscular hypotonia, epilepsy, and kyphoscoliosis were associated features in several cases, as were extremes of short stature and low weight. A supernumerary chromosome was found in all six cases, and it appears that there may be a separate syndrome associated with partial trisomy of chromosome 15.

This report concerns a 6-year-old girl who showed peculiar symptoms but responded favourably to L-dopa. She developed normally until around 1 year of age, at which time head instability, hypotonia, increased deep tendon reflexes and choreoathetotic movements developed. These symptoms appeared to worsen in the afternoon and were alleviated after sleep. An extremely small dose of L-dopa (2 mg/kg) showed dramatic effects and her symptoms disappeared. This condition may be associated with the supersensitivity of the dopamine receptors, caused by hypofunction of the dopamine neurones.

A 30-month-old male exhibited marked hypotonia at birth accompanied by respiratory distress necessitating ventilator support. He subsequently demonstrated marked improvement in muscle power. He became independent of the respirator at 21 days of age and was able to sit without support at 11 months and walked alone at 24 months. Histopathologic analysis of the quadriceps femoris muscle confirmed the diagnosis of congenital fiber type of disproportion at 11 months of age. No other studies have described a patient with a severe neonatal form of congenital fiber type of disproportion who demonstrated such clear improvement. Physicians should be aware of this possibility when they interact with such patients and their families.

We describe 6 newborns evaluated for hypotonia, later diagnosed with Prader-Willi syndrome despite the absence of the classical neonatal features of this syndrome. Specific genetic testing for Prader-Willi syndrome should be considered for all neonates with undiagnosed central hypotonia even in the absence of the other major features of this syndrome.

A boy with an abnormal auditory brain stem response showing only a wave I-II pattern, congenital nystagmus, psycho-motor retardation, pyramidal tract signs and muscular hypotonia was reported. The auditory brain stem response, short latency somatosensory-evoked potential, somatosensory-evoked potential and visual-evoked potential indicated an intramedullary disorder of conduction. Magnetic resonance imaging revealed marked high signal intensity of the cerebral white matter in T2-weighted images, suggesting hypomyelination. A muscle biopsy specimen showed neurogenic changes with mild myogenic changes.

Objective The kyphoscoliotic type of the Ehlers-Danlos (EDSVIA) is a rare connective tissue disorder characterized by kyphoscoliosis, muscular hypotonia prominent in the neonatal period, joint hypermobility, easily bruisable skin, and occasionally rupture of the eye globe and vessels. Patients generally present with motor developmental delay. The clinical presentation among individuals affected with EDS VIA is variable, and genotype-phenotype correlation has not been established yet. Mutations in PLOD1 leading to deficiency of the enzyme lysyl hydroxylase 1 (LH1) cause underhydroxylation of collagen lysyl residues and, hence, abnormal formation of collagen cross-links. This results in an abnormal urinary excretion pattern of lysyl-pyridinolines (LP) and hydroxylysyl-pyridinolines (HP) cross-links. Therefore, the diagnosis of EDS VIA relies on the demonstration of a markedly increased ratio of total LP to HP (LP/HP), and may then be confirmed by molecular genetic analysis of PLOD1. Patients A 8.5-year-old girl, and her 11-year-old brother from a consanguineous family was evaluated because of developmental delay, scoliosis and laxity. Diagnosis at referral was Ullrich congenital muscular dystrophy. Skin lesions, joint hyper laxity, hyperelastic and fragile skin were additional clinical clues for EDSVIA. Conclusions We present a family with two affected siblings both showing increased urinary LP/HP ratio, harboring a homozygous large duplication (c.975+975_1755+? dup; p.Glu326_Lys585dup) between exon 10 and 16 of PLOD1, and showing broad intra-familial clinical variability especially in the degree of severity of kyphoscoliosis and gross-motor involvement.

CDKL5 mutations have been found in children diagnosed with Infantile Spasms, West Syndrome, Lennox-Gastaut, Rett Syndrome, cerebral palsy and autism. However, it is important to note that it is not know what causes CDKL5 mutations, or the full spectrum of CDKL5 disorders at this time. We observed the girl born from 3 pregnancy, 1 birth with weight 3040 and length 50cm. In age of 3 month was carried out adsorbed pertussis-diphtheria-tetanus vaccination and polio, in about 2 weeks after started paroxysms:staring and loss of muscular tonus, lasting a few seconds, also serial infantile spasms. At video-EEG hypsarhythmia and 3 seizures were registered. Neurological status: deformation of heard, can't hold head up, diffuse muscular hypotonia, no visual concentration, reflexes symmetrical, positive Babincki symptom. At that time she was observed with diagnosis: symptomatic generalized epilepsy, perinatal CNS damage, developmental delay. Antiepileptic treatment included: carbamazepine 30 mg/kg/day, valproic acid 50–300 mg/kg/day, topiramate 6–7 mg/kg/day, Phenobarbital 7 mg/kg/day, lamotrigine 2 mg/kg/day, tetracosactide (Synacthen depot) No. 10 in different combinations, but seizures persisted. In 2012 was observed in clinic at Germany: noted focal myoclonic and tonic seizures, with moving eyes upward and infantile spasms serial 5–20 per day, she received clonazepam, levetiracetam, vigabatrin, valproic acid, zonisamide, aethosuximidi in different combinations. In 2014 was made genetic tasting. Was diagnosed early infantile epileptic encephalopathy, type 2 (early infantile form of Rett synrdrome), OMIM 300672. DNA analyses found not known before mutation in CDKL5, X-linked dominant. Nowadays, the girl have redused cognitive development, didn't speak and respond on examination, doesn't contact, have stereotypical movements, no visual contact, have salivation, diffuse muscular hypotonia, reflexes are symmetrical, she doesn't walk, can sit. Antiepileptic treatment includes: valproic acid 600 mg/kg/day and ethosuximid 8 ml/day. Still present generalized tonic-clonic seizures with turning head to the right 1 min 1–2 times a day with breaks 2–5 days, selection of therapy still continues.

We describe a patient in whom full monosomy 21 was initially assumed from routine GTG-banded karyotyping. Re-examination with chromosome painting demonstrated an unbalanced translocation between the long arms of chromosomes 18 and 21. Fluorescence in situ hybridisation (FISH) and microsatellite marker analysis revealed partial monosomy of chromosome 21 (pter-q21) and 18(q22-qter). The patient, 18 years old at the second examination, revealed multiple dysmorphic features, genital hypoplasia, dilated cerebral ventricles, muscular hypotonia and severe mental retardation. In not one out of all patients investigated postnatally in whom an initial examination had revealed monosomy 21, this could be confirmed by FISH; in all of them, re-examination detected an unbalanced rearrangement leading to only partial monosomy 21 plus partial monosomy of another chromosome to which the distal 21q segment was attached. Thus, it is still highly likely that full monosomy 21 is incompatible with intra-uterine survival.

M. Pompe (acid maltase deficiency) is a lysosomal storage disorder leading to progredient heart failure and muscular weakness. In the most severe—that is, the infantile form—children present with cardiomyopathy, extreme muscular hypotonia, and early respiratory failure. They normally die in the first year of life. Adult patients present clinically with skeletal muscular weakness and/or respiratory failure due to insufficiency of the diaphragm muscle. In the medical literature, standardized studies are available only of infantile-onset Pompe disease patients. The age of our patient cohort ranged from 4 to 63 years (N = 11; mean [SD], 32.5 [18] years). In our standardized Pompe disease protocol, we performed lung function tests in the upright and supine positions, as well as the 6-minute walk test, before and 6 months after the start of enzyme replacement therapy (ERT) with alglucosidase alfa (20 mg/kg body weight every other week). As a parameter for lung function, we analyzed the forced vital capacity (FVC). All values were corrected for age, weight, and length, especially in children. Weakness of the diaphragm muscle was defined as loss of >20% of FVC in the supine compared with the upright position. The mean (SD) FVC in the upright position increased from 2.35 (1.06) L before ERT to 2.53 (1.06) L after 6 months of therapy (P = 0.028) (Figure). In the supine position, the FVC also changed significantly from 1.93 (1.03) L to 2.14 (1.11) L (P = 0.004). Five of 11 patients had diaphragm muscle weakness. They showed a similar increase in FVC.

STIM1, a Ca2+-sensing protein on ER/SR membrane, mediates a store-operated Ca2+-entry (SOCE) by activating Orai1 Ca2+-entry channel on plasma membrane. E136X mutant of STIM1, truncated STIM1 missing binding abilities to Orai1, has been found in patients with immunodeficiency accompanying muscular hypotonia. To identify causes of the muscular hypotonia, E136X was expressed in mouse skeletal myotubes and dominant-negative effects of E136X were examined. Myotubes expressing E136X showed increases in both KCl (a membrane depolarizer resulting excitation-contraction coupling) and caffeine (a direct RyR1 agonist) responses. On the other hand, SOCE, resting cytosolic Ca2+ level, SR Ca2+ level were not significantly changed by the expression of E136X. In addition, E136X did not interfere with puncta formations by endogenous STIM1 and Orai1. These data mean that muscular hypotonia found in patients with E136X is due to changes in excitation-contraction coupling. Additionally, we suggest that C-terminus of STIM1 that is missing in E136X participates in the regulation of skeletal EC coupling.

Background: Pompe disease is a rare autosomal recessively inherited lysosomal storage disorder caused by mutations of the gene coding for acid -glucosidase. Patients with the classic early onset usually come to attention in early life with marked muscular hypotonia and heart failure caused by hypertrophic cardiomyopathy. Without treatment, Pompe disease is fatal within the first year, mostly from cardiorespiratory failure. Central nervous system complications associated with this disorder are rarely reported. We describe here a case of a 4 months and a half-old girl with diagnosis of Pompe disease after an acute hydrocephalus. Case Report: The clinical history starts with feeding difficulties and fatigue reported by the mother. The pediatrician noticed a systolic murmur and referred the infant for cardiac examination which revealed hypertrophic cardiomyopathy. The following day and before clinical deterioration, the infant was admitted to the pediatric emergency where a full anterior fontanel was found. Additional clinical examination revealed an associated increased head circumference and axial hypotonia. Cerebral computed tomography showed a severe hydrocephalus with dilatation of the four ventricles. The infant underwent an acute placement of a ventriculoperitoneal shunt. Post-surgery surveillance biological tests showed slightly increased levels of CK (518 Ul/L) and increased levels of transaminases (ALT 176 Ul/L, AST 116 Ul/L). A metabolic disorder was evoked and Pompe disease was diagnosed. ERT was started immediately after exhaustive work-up. Despite ERT, this girl developed diffuse and evolutive leukopathy on MRI with evidence of dysmyelinisation on magnetic resonance spectroscopic imaging.

Summary A neurological follow up study was done of 143 full-term infants who were small for gestational age based on intrauterine growth retardation and of 49 preterm appropriate-for-gestational-age (PTAGA) infants at the age of 6 years. Findings were compared with those of a reference group of 192 full-term appropriate-forgestational-age (FTAGA) children. In 11 % of the children of both study groups, hypotonia was found without any other neurological deviancy. This type of hypotonia was absent in the reference group, whereas minor neurological dysfunction consisting of hypotonia with other neurological signs was found in all the three groups of children. No relation was found with obstetrical or neonatal variables, including severity of growth retardation and gestational age, or with weight, body height or head circumference at 6 years. The possible interference of preterm birth or intrauterine growth retardation with, and the role of placental mechanisms in, fetal and early postnatal muscle development is discussed.

Resume Differentes formes d'hypotonie resultant de diverses lesions dans le systeme somato-sensoriel sont presentees. A ce propos, les reflexes segmentaires ont ete etudies dans les muscles flexeurs du bras a l'aide de l'electromyographie. L'accent est mis sur les patients souffrant de Parkinson, et operes stereotaxiquement dans le but de soulager le tremblement. Ces patients ont ete etudies avant et apres l'operation et les resultats ont ete compares a ceux obtenus des sujets normaux. Cette comparaison a montre que la composante M2 de la reponse EMG segmentaire etait toujours plus ample avant l'operation. Ceci pourrait etre le resultat d'une decharge a haute frequence d'unites motrices, comme le suggerent les observations au niveau unitaire. Apres l'operation, la composante M2 est significativement reduite en relation avec l'hypotonie clinique. Il est propose que l'hypotonie observee chez le patient Parkinsonien apres subthalamotomie et/ou thalamotomie pourrait etre le resultat de la reduction de la composante M2. Les voies anatomiques qui pourraient etre interrompues et qui pourraient servir de passage a des reflexes a longue latence sont mentionnees. Il est aussi propose que la lesion stereotaxique pourrait influencer selectivement la motricite des fuseaux chez le Parkinsonien.

A 4-year-old boy with a history of muscular hypotonia, mental retardation, microcephaly, and generalized convulsions was found at autopsy to have agyria, agenesis of the anterior commissure and posterior corpus callosum as well as an abnormal decussation of pyramidal tracts which descended in the spinal dorsal columns. Postmortem muscular alterations included type IIc fiber hypertrophy and type I fiber grouping, variably expressed in individual muscles and intramuscular fascicles. This may represent a developmental delay compatible with a gestational age between the 34th and 40th week. These studies also indicate the importance of examining (a) multiple samples of postmortem muscles and (b) muscles from patients afflicted with cerebral malformations.