[Central manifestations of dystrophinopathies]

The dystrophin gene involved in Duchenne and Becker muscular dystrophy is expressed in three main tissues resulting in clinical manifestations: skeletal muscle, heart and central nervous system. The 6 different existing dystrophins in the brain may play a role in the maturation and plasticity of neuronal synapses in particular by their functions in clustering and stabilization of different receptors at the post synaptic membrane. The possibility of an intellectual deficiency in Duchenne muscular dystrophy is known from the original description by Duchenne himself. Current data are in line with a constant cognitive impairment with a Gaussian curve shifted intellectual quotient (IQ) at -1 standard deviation from the standard population with an average IQ around 80. Clinical manifestations suggestive of a central nervous system involvement can affect all dystrophinopathies, including isolated central presentations without myopathic sign. The phenotypic spectrum appears broader and more subtle than non specific intellectual deficiency. The isolated or shared involvement of specific cognitive functions is possible (memory functions, executive functions, attention) with or without intellectual deficiency. Autism spectrum disorders are also among the encountered events. In clinical practice, it seems worth to ask for a measurement of serum creatine kinase (CK) in these different situations, keeping in mind that pure forms of central dystrophinopathies with a normal CK level have been recently reported.

Botulinum toxin treatment of pes cavovarus in a child suffering from autosomal recessive axonal Charcot-Marie-Tooth neuropathy (AR-CMT2)

In a 12-year old girl suffering from autosomal recessive axonal Charcot-Marie-Tooth (CMT) neuropathy, pes cavovarus was treated with botulinum toxin injection in the tibialis posterior. The patient underwent a clinical evaluation, video analysis of spatiotemporal gait parameters and dynamic foot plantar pressure assessment before treatment and then two weeks, three months and six months thereafter. The video gait analysis revealed a decrease in varus during the swing phase of gait. The dynamic foot plantar pressure decreased by 50% in the excessive pressure at the side of the foot six months after the injection (maximal pressure=42.6N/cm2 before treatment and 18.9 N/cm2 after 6 month). Botulinum toxin injection appears to be an efficacious means of correcting pes cavovarus in CMT disease. A larger-scale clinical trial is now required to evaluate the putative longer-term preventive effect of this treatment on the pes cavus deformity.

[Multicentric study of medical care and practices in spinal muscular atrophy type 1 over two 10-year periods]

AIM

Questions about care practices and the role of palliative care in pediatric neurodegenerative diseases have led the Neuromuscular Committee of the French Society of Neurology to conduct a retrospective study in spinal muscular atrophy type 1, a genetic disease most often leading to death before the age of 1 year.

MATERIAL AND METHODS

A retrospective multicenter study from pediatricians included in the reference centers of pediatric neuromuscular diseases was carried out on two 10-year periods (1989-1998 and 1999-2009).

RESULTS

The 1989-1998 period included 12 centers with 106 patients, the 1999-2009 period 13 centers with 116 children. The mean age of onset of clinical signs was 2.1 months (range, 0-5.5 months), the median age at diagnosis was 4 months (range, 0-9 months) vs 3 months. The median age of death was 7.5 months (range, 0-24 months) vs 6 months. The care modalities included physiotherapy (90 %), motor support (61 % vs 26 % for the previous period), enteral nutrition by nasogastric tube (52 % vs 24 %), and 3.4 % of children had a gastrostomy (vs 1.8 %). At home, pharyngeal aspiration was used in 64 % (vs 41 %), oxygen therapy in 8 %, noninvasive ventilatory support in 7 %. The mean age at death was 8.1 months (range, 0-24 months) vs 7 months, the time from diagnosis to death was 4 months vs 3 months. Death occurred at home in 23 % vs 17 %, in a pediatric unit in 62 % vs 41 %. The use of analgesics and sedative drugs was reported in 60 % of cases: 40 % morphine (vs 18 %) and benzodiazepines in 48 % (vs 29 %). Respiratory support was limited mostly to oxygen by nasal tube (55 % vs 54 %), noninvasive ventilation in 9 % of the cases, and intubation and assisted mechanical ventilation (2 %).

DISCUSSION AND CONCLUSION

These results confirm a change in practices and the development of palliative care in children with a French consensus of practices quite different from the standard care in North-America and closer to the thinking of English medical teams. A prospective study within the 2011 national hospital clinical research program (PHRC 2011) is beginning in order to evaluate practices and the role of families and caregivers.

[Muscle biopsy in children: Usefulness in 2012]

Muscle biopsy is a mainstay diagnostic tool for investigating neuromuscular disorders in children. We report the yield of pediatric muscle biopsy in a population of 415 children by a retrospective study of 419 biopsies performed between 1/01/2000 and 31/12/2009 in a neuropediatric department, including mitochondrial respiratory chain analysis for 87 children. Two hundred and fifty-five biopsies were from boys (61%) 164 from girls (39%). Their mean age at biopsy was 6.5years; 155 (37%) biopsies were obtained before the child was 5years old. Final histopathological diagnoses were: congenital myopathy (n=193, including 15 structural congenital myopathies); progressive muscular dystrophy (n=75 [18%] including 57 dystrophinopathies); congenital muscular dystrophy (n=17, including six primary merosinopathies); dermatomyositis (n=11); spinal muscular atrophy (n=9, including six atypical spinal muscular atrophies); metabolic myopathy (n=32, including 19 mitochondrial myopathies); encephalomyopathy (n=53 [13%], including 27 with a mitochondrial respiratory chain defect). Pathological diagnosis remained undetermined in 16 cases. In 184 patients (44%), the muscle biopsy revealed specific histopathological anomalies (dystrophic process; specific ultrastructural abnormalities; perifascicular atrophy; neurogenic atrophy; metabolic anomalies) enabling a precise etiological diagnosis. For 85% of progressive muscular dystrophies, the biopsy resulted in a genetic diagnosis after identification of the protein defect. In 15% of the congenital myopathies, histopathological anomalies focused attention on one or several genes. Concerning dystrophinopathies, quantification of dystrophin deficiency on the biopsy specimen contributed to the definition of the clinical phenotype: Duchenne, or Becker. In children with a myopathy, muscle biopsy is often indispensable to establish the etiological diagnosis. Based on the results from this series, muscle biopsy can provide a precise orientation in 45% of patients, leading to a genetic hypothesis.

Recommendations for the diagnosis and management of typical childhood spinal muscular atrophy

Typical childhood spinal muscular atrophy is a disease that affects the anterior horn of the spinal cord related to SMN1 gene defects. Since no etiological treatment is currently available, its management is necessarily symptomatic and involves multidisciplinary care. The national plan on rare diseases for 2005-2008 developed by the French Ministry of Health resulted in the creation of 12 reference centres for neuromuscular diseases, mainly to improve their diagnosis and management. During the first one-day clinical research meeting on neuromuscular disorders, organized by the French Association to fight myopathies (AFM) in May 2007, clinicians from the 12 national reference centers led workshops for each of the main neuromuscular diseases. Concerning spinal muscular atrophy, discussions involving specialists from medical and allied professions were led by clinicians in charge of the workshop sessions. This paper reports the final version of their recommendation regarding the diagnosis, monitoring and management of typical infantile spinal muscular atrophy, which is necessarily multidisciplinary, including orthopedic, pulmonary, gastroenterology and nutrition care.

[Characteristics of tuberous sclerosis in children]

Tuberous sclerosis complex is a genetic multisystem disease characterized by hamartic development of many organs, most notably the brain, heart, kidneys, lungs, and skin. This autosomic dominant disorder results from mutations in one of two genes, TSC1 and TSC2, coding for hamartin and tuberin, respectively. The hamartin-tuberin complex inhibits the mammalian target of rapamycin pathway, which controls cell growth and proliferation. The clinical presentation is highly variable and most features of tuberous sclerosis become evident only in childhood after the child is several years of age, limiting their usefulness for early diagnosis. The aim of this article is to define the pediatric clinical manifestations of tuberous sclerosis in correlation with patient age. Sometimes, a prenatal diagnosis can be made based on fetal ultrasound and MRI, which show cardiac and brain lesions. However, newborns are most often asymptomatic. In the 1st year, seizures are the most common symptoms, with a high incidence of infantile spasms. In children between 2 and 10 years of age, neurological symptoms are the most frequent with epilepsy, mental retardation, and autism, but extraneurological manifestations can be diagnosed. In adolescents, most features of tuberous sclerosis become evident and renal and pulmonary manifestations must be sought. The knowledge of age-dependent clinical features of tuberous sclerosis can provide an earlier diagnosis and improve the management of these patients with a special role for multidisciplinary consultation.

Delineation of 15q13.3 microdeletions

The increasing use of array-comparative genomic hybridization (array-CGH) to identify copy number variations (CNVs) in patients with developmental delay (DD), mental retardation and/or dysmorphic features has allowed the recent recognition of numerous genomic imbalances, including the 15q13.3 microdeletion. Patients with this microdeletion generally present with relatively consistent breakpoints at BP4 and BP5, which include the CHRNA7 gene. About 100 index cases have been reported since the first publication in 2008. This large number of patients ascertained through highly variable samples has been necessary to describe the full phenotypic spectrum of this microdeletion, ranging from mental retardation with dysmorphic features, epilepsy, neuropsychiatric disturbances with or without cognitive impairment to complete absence of anomalies. Here, we describe a collaborative study reporting a new cohort of 12 index patients and 13 relatives carrying a heterozygous BP4-BP5 microdeletion out of a series of 4625 patients screened by array-CGH for DD. We confirm the clinical expressivity of the disease as well as the incomplete penetrance in seven families. We showed through a review of the literature that males are more likely to be symptomatic. Sequence analysis of CHRNA7 yielded no data to support the unmasking of recessive variants as a cause of phenotypic variability. We also report the first patient carrying a 15q13.3 homozygous microdeletion inherited from both parents. He had severe epileptic encephalopathy with retinopathy, autistic features and choreoathetosis. Besides the classical approximately 1.5 Mb BP4-BP5 microdeletion, we also describe three index patients and two relatives with a smaller 500 kb microdeletion, including the CHRNA7 gene.

Clinical and mutational spectrum of limb-girdle muscular dystrophy type 2I in 11 French patients

BACKGROUND

Limb-girdle muscular dystrophy 2I (LGMD2I) is caused by mutations in the fukutin-related protein gene FKRP, which is also involved in congenital muscular dystrophy (MDC1C).

OBJECTIVE

To evaluate the clinical, biological, radiological and mutational characteristics of LGMD2I patients with FKRP mutation.

METHODS

Eleven patients from nine families from the north of France were studied. Demographical data, muscular testing results, cardiac and respiratory examinations, muscle histological features and a genetic analysis of the FKRP gene for each patient are reported. Eight patients underwent brain MRI and seven neuropsychological tests.

RESULTS

The patients included six women and five men. The mean age at onset was 9 years (range 1.5 to 23 years). Five patients remained self-ambulatory, whereas the other six were confined to a wheelchair by a mean age of 19 years, after a mean disease duration of 10 years. Nine patients suffered from restrictive respiratory insufficiency, and two male patients had severe dilated cardiomyopathy. Neuropsychological tests revealed memory impairment in four cases. Brain MRI revealed cerebral abnormalities in four patients (4/8). Ten patients were carriers of the common L276I mutation, which was either homozygous (four patients) or heteroallelic with another mutation (six patients). Among the mutations found, three were novel: L322V, L489R and R275G.

CONCLUSIONS

This study reveals inter- and intrafamilial phenotypic variability in LGMD2I, with a preponderance of myocardiopathy and restrictive respiratory insufficiency. It also demonstrates central nervous involvement, probably associated with changes in alpha-dystroglycan expression in the brain.

The value of electromyography in the aetiological diagnosis of hypotonia in infants and toddlers

INTRODUCTION

During the first two years of life, hypotonia may be the only symptom of a central or peripheral nervous system disorder. We propose to assess the sensitivity of electroneuromyography (ENMG) in the aetiological diagnosis of hypotonia of neuromuscular origin in infants and toddlers.

METHOD

This is a retrospective, single-centre study with revision of the files of the 37 children aged between zero and 24 months who, between 1994 and 2006, underwent an ENMG in the etiological approach of their hypotonia and had a final diagnosis of neuromuscular disease.

RESULTS

All the 13 patients with spinal muscular atrophy or Charcot Marie-Tooth disease displayed neurogenic alterations on the electromyography (EMG). Among the 24 children ultimately diagnosed with myopathies, five only displayed myogenic alterations when tested before the age of two. Sixteen had normal EMG results and three showed neurogenic alterations.

DISCUSSION AND CONCLUSION

In infants presenting with hypotonia, ENMG is useful for the diagnosis of peripheral neuropathy. Normal ENMG is relatively common for confirmed muscle disorders in infants whereas myogenic alterations seem more unusual, so that muscle biopsy appears unquestionable. In a few cases, early onset myopathies may present with a neurogenic ENMG pattern. Such a result should not invalidate the clinically presumed diagnosis of myopathy and would indicate on the contrary the need for a muscle biopsy.

[Interest of the ketogenic diet in a refractory status epilepticus in adults]

INTRODUCTION

Ketogenic diets have been employed for the treatment of intractable epilepsy in children since 1921, although underlying mechanism remains unknown.

OBSERVATION

We report the case of a 54-year-old man with partial refractory status epilepticus who exhibited a favourable outcome about seven days after introduction of a ketogenic diet in association with antiepileptic drugs.

DISCUSSION

Although its efficiency was largely demonstrated in children, little is known about the impact of a ketogenic diet in adults with refractory epilepsy.

CONCLUSION

Introduction of a ketogenic diet requires a multidisciplinary approach. Its usefulness in adult intractable epilepsy and/or refractory status epilepticus merits further study into its efficacy in reducing the frequency of seizures and a possible prolonged effect.

New POMT2 mutations causing congenital muscular dystrophy: identification of a founder mutation

BACKGROUND

Dystroglycanopathies are a group of congenital muscular dystrophies (CMDs) with autosomal recessive inheritance, often associated with CNS and ocular involvement. They are characterized by the abnormal glycosylation of alpha-dystroglycan, and caused by mutations in at least six genes encoding enzymes: FKTN, POMGNT1, POMT1, POMT2, FKRP, and LARGE. POMT2 mutations have recently been identified in Walker-Warburg syndrome and in a milder muscle-eye-brain disease-like form.

METHODS

We studied mentally retarded patients with CMD, analyzed POMT2 by sequencing the coding regions, and also performed a haplotype analysis in all patients and their family members carrying the new POMT2 mutation.

RESULTS

We report three novel POMT2 mutations. One of these, p.Tyr666Cys, was homozygous in two unrelated patients and in a compound heterozygous state in others. All patients showed severe diffuse muscle weakness, microcephaly, severe mental retardation, and marked lordoscoliosis with hyperextended head. Elevated CK levels, cerebral cortical atrophy, and cerebellar vermis hypoplasia were constant findings. Mild cardiac abnormalities, focal white matter abnormalities, or partial corpus callosum hypoplasia were detected in single cases. Eye involvement was absent or mild. By genotype analysis, we defined a distinct 170kb haplotype encompassing POMT2 and shared by all the subjects harboring the mutation p.Tyr666Cys.

CONCLUSIONS

Our results broaden the clinical spectrum associated with POMT2 mutations, which should be considered in patients with CMD associated with microcephaly, and severe mental retardation with or without ocular involvement.

[Effect of thoracic bracing on lung function in children with neuromuscular disease]

Respiratory muscle weakness associated with scoliosis in neuromuscular disease leads to respiratory impairment. Children with scoliosis are usually treated with spinal bracing to delay the progress of disease. We studied the impact of spinal bracing on lung function in these children.

METHODS

Retrospective study of patient data from January 1997 to January 2003. Spirometry and measurement of lung volume involved 32 observations, corresponding to 17 children with neuromuscular disease, including 14 with spinal muscular atrophy. Data for children with and without a brace were studied.

RESULTS

A total of 72% of the children had severe scoliosis (Cobb score>30 degrees ); 40% wore a Garchois brace. Children without a brace showed a mean vital capacity of 65% of predicted value, with a restrictive syndrome in 44% of observations. Children with a brace showed significantly reduced vital capacity (-4.6%; P<0.001) and forced expiratory volume in 1 s (-4.6%; P=0.002). The reduced vital capacity was lower in children with the Garchois brace: -1% (P=0.02). Severity of scoliosis and measured volumes were not related.

CONCLUSION

Spinal bracing in children with neuromusclar disease leads to significant respiratory impairment. Assessment of pulmonary function is necessary when a brace is indicated. The Garchois brace might lead to less impairment of respiratory function.

[Phenotypic aspects of FKRP-linked muscular dystrophy type 2I in a series of eleven patients]

INTRODUCTION

Limb-girdle muscular dystrophy type 2I (LGMD2I) is caused by mutations in the fukutin related protein gene (FKRP gene). This study tries to evaluate clinical, biological and mutational characteristics of LGMD2I.

PATIENTS AND METHODS

Eleven patients belonging to 9 families from the North of France were selected. We reported demographic data, and results of muscular testing, cardiac, and respiratory examination, as well as the histopathological features of muscle tissue and a genetic analysis of FKRP gene for each patient.

RESULTS

There were 6 females and 5 males. Mean age at onset was 9.7 years old. Six had Duchenne like phenotype, 5 Becker like phenotype. Nine patients suffered from restrictive respiratory failure, two males had severe dilated cardiomyopathy. Ten patients had the common L276I mutation. Three mutations had not been previously identified: L322V, L489R and R275G heterozygous mutations associated with the L276I mutation.

CONCLUSION

This study underlines inter and intra familial phenotypic variability in LGMD2I, preponderance of cardiomyopathy in males and restrictive respiratory insufficiency in female.

'Cap myopathy': case report of a family

We report the observation of an 18-year-old girl, whose clinical presentation was very suggestive of a congenital myopathy with neonatal onset. A congenital myopathy had been already diagnosed in her brother and in addition her half-cousin died diagnosed with a severe nemaline myopathy at age 4 years. A muscle biopsy performed on both siblings revealed histological and ultrastructural features of 'cap myopathy'. This case report suggests that 'cap myopathy' and some cases of nemaline myopathy with neonatal onset might be two phenotypic expressions of the same genetic disorder. These two entities could therefore, perhaps, be regarded as 'Z-line disorders' possibly caused by defective myofibrillogenesis.

Small vessel abnormalities in alternating hemiplegia of childhood: Pathophysiologic implications

BACKGROUND

The pathophysiology of alternating hemiplegia of childhood (AHC) is unclear. The authors evaluated the skin and muscle biopsies from patients with AHC for vascular abnormalities.

METHODS

Skin biopsy specimens from four patients ages 18 months, 8 years, 9 years, and 18 years and muscle biopsies from two of these patients were examined by electron microscopy and compared with healthy controls.

RESULTS

Vascular abnormalities were found in both skin and muscle. Skin biopsies showed similar abnormalities in all four patients. Vacuoles were visible in the endothelium. The most striking abnormality was the presence in the tunica media of small and unevenly shaped vascular smooth muscle cells (VSMCs) containing intracytoplasmic vacuoles and, occasionally, apoptotic nuclei, with variations according to patient age. Moreover, most VSMCs had lost junctions with neighboring cells, and some were completely isolated. In vessels from muscle biopsies, the VSMCs showed vacuoles, residual osmiophilic deposits, and myofilament loss with substitution by vacuoles.

CONCLUSIONS

The vascular abnormalities in our patients suggest a primary or secondary vascular pathophysiology to alternating hemiplegia of childhood. The vascular smooth muscle cells may be the initial target of the disease process.

[Neuropediatric approach to autism]

Autism is defined by 3 main criteria: disturbance of reciprocal social interaction, disturbance of communication (including language comprehension and spoken language) and disturbance of normal variation in behaviour and imaginative activities; an onset before age 36 months is also required. The neuropediatric contribution to autism is dominated by the search for an underlying organic etiology, especially if there are arguments for an associated encephalopathy: ante- or perinatal medical history, dysmorphic signs, skin spots, neurological abnormalities, somatic abnormalities compatible with a neurometabolic disorder. The main associated conditions with autism are: chromosome anomalies, monogenic syndrome (including fragile X syndrome), neurocutaneous syndromes, epileptic encephalopathies, neurometabolic diseases, and dystrophinopathies. The identification of an associated medical condition to autism is primordial in prospect of genetic counselling, and by the change induced in familial perception of autism.

Troubles psychiatriques révélateurs d’une maladie de Niemann-Pick de type C à l’âge adulte

INTRODUCTION

Niemann-Pick Type C disease (NPC) is an autosomal recessive neurovisceral lysosomal lipid storage disorder.

CASE REPORT

A 31-year-old right-handed woman had suffered from schizophrenia for 13 years. At 25 years of age, she developed a gait disorder with a static and kinetic cerebellar syndrome, dysarthria, vertical supranuclear gaze palsy and cognitive impairment. Brain MRI was normal. Abdominal ultrasonography was performed because of hypercholesterolemia and elevated transaminases and revealed hepatosplenomegaly, which in conjunction with other signs and symptoms, suggested the diagnosis of NPC. The diagnosis was confirmed by demonstration of lysosomal storage of unesterified cholesterol (filipin staining) and of a reduced rate of LDL-induced cholesterol esterification. Implication of the NPC1 gene was assessed by genetic complementation analysis.

DISCUSSION

The phenotypic presentation of NPC is remarkably variable. The rarer adult-onset form has a slowly progressive course. Psychotic manifestations are often prominent and may precede neurologic symptoms. Exposure to neuroleptics delays the diagnosis of NPC.

CONCLUSION

Psychotic manifestations associated with cerebellar syndrome, vertical supranuclear gaze palsy, and splenomegaly are very suggestive of NPC disease which can be reliably diagnosed on cultured skin fibroblasts by filipin staining.

Patients with familial partial lipodystrophy of the Dunnigan type due to a LMNA R482W mutation show muscular and cardiac abnormalities

Diseases due to mutations in the lamin A/C gene (LMNA) are highly heterogeneous, including neuromuscular and cardiac dystrophies, lipodystrophies, and premature ageing syndromes. In this study we characterized the neuromuscular and cardiac phenotypes of patients bearing the heterozygous LMNA R482W mutation, which is the most frequent genotype associated with the familial partial lipodystrophy of the Dunnigan type (FPLD). Fourteen patients from two unrelated families, including 10 affected subjects, were studied. The two probands had been referred for lipoatrophy and/or diabetes. Lipodystrophy, exclusively observed in LMNA-mutated patients, was of variable severity and limited to postpubertal subjects. Lipodystrophy and metabolic disturbances were more severe in women, even if an enlarged neck was a constant finding. The severity of hypertriglyceridemia and hirsutism in females was related to that of insulin resistance. Clinical muscular alterations were only present in LMNA-mutated patients. Clinical and histological examination showed an invalidating, progressive limb-girdle muscular dystrophy in a 42-yr-old woman that had been present since childhood, associated with a typical postpubertal FPLD phenotype. Six of eight adults presented the association of calf hypertrophy, perihumeral muscular atrophy, and a rolling gait due to proximal lower limb weakness. Muscular histology was compatible with muscular dystrophy in one of them and/or showed a nonspecific excess of lipid droplets (in three cases). Immunostaining of lamin A/C was normal in the six muscular biopsies. Surprisingly, calpain 3 expression was undetectable in the patient with the severe limb-girdle muscular dystrophy, although the gene did not reveal any molecular alterations. At the cardiac level, cardiac septal hypertrophy and atherosclerosis were frequent in FPLD patients. In addition, a 24-yr-old FPLD patient had a symptomatic second degree atrioventricular block. In conclusion, we showed that most lipodystrophic patients affected by the FPLD-linked LMNA R482W mutation show muscular and cardiac abnormalities. The occurrence and severity of the myopathic and lipoatrophic phenotypes varied and were not related. The muscular phenotype was evocative of limb girdle muscular dystrophy. Cardiac hypertrophy and advanced atherosclerosis were frequent. FPLD patients should receive careful neuromuscular and cardiac examination whatever the underlying LMNA mutation.

Analyse d’une population de 100 enfants adressés pour troubles d’apprentissage scolaire

DESIGN

To determine the impact of a neuropediatrician view on diagnosis and management of learning disabilities.

METHOD

Retrospective review of the medical records of the last 100 children attending for learning disabilities from 1st June 2000 through 31st May 2001. Assessment concerned school curriculum, type of management before consultation, diagnosis procedure and type of management following consultation. Differential diagnosis was made in 100% of cases following evaluation.

RESULTS

The three main diagnoses were attentionnal deficit disorder with hyperactivity (39%), mental retardation (17%) and dyslexia (7%). Mental retardation and cerebral palsy diagnoses had not been made before consultation. Conversely, 70% of the diagnoses of dyslexia made before consultation were incorrect. Medical treatment was proposed in 38% of cases and modification in the management in 59% of cases.

CONCLUSION

This study highlights the interest of a rigorous diagnosis procedure for learning disabilities, based on a neuropediatrics examination, a cognitive evaluation and phonological and lexical evaluation. It only may lead to an appropriate management.

GUG is an efficient initiation codon to translate the human mitochondrial ATP6 gene

A maternally inherited and practically homoplasmic mitochondrial (mtDNA) mutation, 8527A>G, changing the initiation codon AUG into GUG, normally coding for a valine, was observed in the ATP6 gene encoding the ATPase subunit a. No alternate Met codon could replace the normal translational initiator. The patient harboring this mutation exhibited clinical symptoms suggesting a mitochondrial disease but his mother who carried the same mtDNA mutation was healthy. The mutation was absent from 100 controls and occurred once amongst 44 patients suspected of Leber Hereditary Optic Neuropathy (LHON) but devoid of typical LHON mutations. In patient fibroblasts, no effect of 8527A>G mutation could be demonstrated on the biosynthesis of mtDNA-encoded proteins, on size and the content of ATPase subunit a, on ATP hydrolysis and on mitochondrial membrane potential. In addition, ATP synthesis was barely decreased. Therefore, GUG is a functional initiation codon for the human ATP6 gene.

Clinical and molecular genetic spectrum of autosomal dominant Emery-Dreifuss muscular dystrophy due to mutations of the lamin A/C gene

Emery-Dreifuss muscular dystrophy (EDMD) is characterized by early contractures of the elbows and Achilles tendons, slowly progressive muscle wasting and weakness, and life-threatening cardiomyopathy with conduction blocks. We recently identified LMNA encoding two nuclear envelope proteins, lamins A and C, to be implicated in the autosomal dominant form of EDMD. Here, we report on the variability of the phenotype and spectrum of LMNA mutations in 53 autosomal dominant EDMD patients (36 members of 6 families and 17 sporadic cases). Twelve of the 53 patients showed cardiac involvement exclusively, although the remaining 41 all showed muscle weakness and contractures. We were able to identify a common phenotype among the patients with skeletal muscle involvement, consisting of humeroperoneal wasting and weakness, scapular winging, rigidity of the spine, and elbow and Achilles tendon contractures. The disease course was generally slow, but we observed either a milder phenotype characterized by late onset and a mild degree of weakness and contractures or a more severe phenotype with early presentation and a rapidly progressive course in a few cases. Mutation analysis identified 18 mutations in LMNA (i.e., 1 nonsense mutation, 2 deletions of a codon, and 15 missense mutations). All the mutations were distributed between exons 1 and 9 in the region of LMNA that is common to lamins A and C. LMNA mutations arose de novo in 76% of the cases; 2 of these de novo mutations were typical hot spots, and 2 others were identified in 2 unrelated cases. There was no clear correlation between the phenotype and type or localization of the mutations within the gene. Moreover, a marked inter- and intra-familial variability in the clinical expression of LMNA mutations exists, ranging from patients expressing the full clinical picture of EDMD to those characterized only by cardiac involvement, which points toward a significant role of possible modifier genes in the course of this disease. In conclusion, the high proportion of de novo mutations together with the large spectrum of both LMNA mutations and the expression of the disease should now prompt screening for LMNA in familial and sporadic cases of both EDMD and dilated cardiomyopathy associated with conduction system disease.

Epignathus teratoma: report of three cases with a review of the literature

Three cases of epignathus teratoma associated with other midline anomalies are reported. The first case involved Pierre Robin sequence and a bifid tongue. The second case was characterized by two teratomas, a meningoencephalocele, and a cleft lip and nose. The third case had Pierre Robin sequence associated with duplication of the pituitary gland and hypoplasia of the corpus callosum.

[Febrile convulsions and other occasional convulsions in children]

Febrile convulsions are the main etiology of the occasional convulsions. They occur between 6 months and 5 years. They are short, bilateral, clonic or tonico-clonic. Febrile convulsions are classified in 2 groups: benign febrile convulsions and complicated febrile convulsions. When it exists, the genetic predisposition is a significant factor recurrent of febrile convulsions, but their prognosis remains good. Treatment depends on the diagnosis of simple or complicated febrile convulsions. The treatment of febrile convulsions is intra-rectal diazepam (0.5 mg/kg). The risks of recurrence of convulsions are inversely proportional to the intensity and duration of the fever episode before the convulsion.

[Holoprosencephaly with neurogenic hypernatremia]

BACKGROUND

Semi-lobar holoprosencephalies can be seldom complicated by neurogenic hypernatremia, which must be distinguished from other causes of hypernatremia.

CASE REPORT

In two admitted children with semi-lobar holoprosencephaly, 7 months and 4 years old, biological data revealed chronic hypernatremia and hyperosmolarity without clinical signs of dehydration, which were finally attributed to a neurogenic hypernatremia.

CONCLUSION

Neurogenic hypernatremia must be clearly differentiated from other causes of hypernatremia since it never causes specific complications.

Acquired and isolated asymmetrical palatal palsy

Benign acquired and isolated asymmetrical palatal palsy is a rare condition in childhood. We report on three cases. Typical features include: sudden onset, abnormality of the palatal components of speech (rhinolalia), nasal escape of fluids from the ipsilateral nostril. It is supposed to be caused by viral infection, but attempts at viral isolation were unsuccessful. Complete spontaneous recovery is usual, taking a few weeks. Our paper seems to be the first report of magnetic resonance imaging of the brain in this condition. It did not disclose any abnormalities in the 2 cases in which it was performed.

[Benign reflex myoclonic epilepsy in infants]

BACKGROUND

Myoclonic epilepsy of infancy are seldom benign.

CASE REPORT

A 25-month old girl developed myoclonic jerks either spontaneously either as reflex responses to auditory and tactile stimuli, such as sudden touching of the face or trunk from the age of 4 months. The jerks disappeared after valproate therapy. Neurological examination was normal with a follow-up of 9 months.

CONCLUSION

This condition resembles that described in 1995 by Ricci et al. In must be differentiated from other myoclonic epilepsies of infancy, reflex epilepsies and hyperekplexia. It could be the earliest from of idiopathic generalized epilepsy.