Myotonia congenita: mutation spectrum of CLCN1 in Spanish patients.

Myotonia congenita (MC) is a Mendelian inherited genetic disease caused by the mutations in the CLCN1 gene, encoding the main skeletal muscle ion chloride channel (ClC-1). The clinical diagnosis of MC should be suspected in patients presenting myotonia, warm-up phenomenon, a characteristic electromyographic pattern, and/or family history. Here, we describe the largest cohort of MC Spanish patients including their relatives (up to 102 individuals). Genetic testing was performed by CLCN1 sequencing and multiplex ligation-dependent probe amplification (MLPA). Analysis of selected exons of the SCN4A gene, causing paramyotonia congenita, was also performed. Mutation spectrum and analysis of a likely founder effect of c.180+3A>T was achieved by haplotype analysis and association tests. Twenty-eight different pathogenic variants were found in the CLCN1 gene, of which 21 were known mutations and seven not described. Gross deletions/duplications were not detected. Four probands had a pathogenic variant in SCN4A. Two main haplotypes were detected in c.180+3A>T carriers and no statistically significant differences were detected between case and control groups regarding the type of haplotype and its frequencies. A diagnostic yield of 51% was achieved; of which 88% had pathogenic variants in CLCN1 and 12% in SCN4A. The existence of a c.180+3A>T founder effect remains unsolved.

Characterization of molecular mechanisms underlying the axonal Charcot-Marie-Tooth neuropathy caused by MORC2 mutations.

Mutations in MORC2 lead to an axonal form of Charcot-Marie-Tooth (CMT) neuropathy type 2Z. To date, 31 families have been described with mutations in MORC2, indicating that this gene is frequently involved in axonal CMT cases. While the genetic data clearly establish the causative role of MORC2 in CMT2Z, the impact of its mutations on neuronal biology and their phenotypic consequences in patients remains to be clarified. We show that the full-length form of MORC2 is highly expressed in both embryonic and adult human neural tissues and that Morc2 expression is dynamically regulated in both the developing and the maturing murine nervous system. To determine the effect of the most common MORC2 mutations, p.S87L and p.R252W, we used several in vitro cell culture paradigms. Both mutations induced transcriptional changes in patient-derived fibroblasts and when expressed in rodent sensory neurons. These changes were more pronounced and accompanied by abnormal axonal morphology, in neurons expressing the MORC2 p.S87L mutation, which is associated with a more severe clinical phenotype. These data provide insight into the neuronal specificity of the mutated MORC2-mediated phenotype and highlight the importance of neuronal cell models to study the pathophysiology of CMT2Z.

Cannabidiol: uso en epilepsias refractarias / Cannabidiol: its use in refractory epilepsies

Introducción. Algunos síndromes epilépticos se caracterizan por crisis de difícil control y asocian un retraso en el desarrollo neuropsicomotor, lo que conlleva un deterioro en la calidad de vida del paciente y su familia. Objetivo. Evaluar el uso del cannabidiol como tratamiento adyuvante en pacientes con epilepsias refractarias. Pacientes y métodos. Se realizó un estudio observacional por medio de una encuesta dirigida a la persona cuidadora del paciente. Se valoró la información sobre el paciente y el cuidador, cambios observados sobre las crisis, efectos neuropsicológicos, efectos adversos y percepción global de la familia tras el uso del cannabidiol. Resultados. Se evaluó a 15 pacientes con epilepsias refractarias, quienes recibieron cannabidiol durante un período de un mes a un año. En el 40% de los pacientes hubo una disminución en la frecuencia de las crisis, en el 60% de los pacientes se observó un control de más del 50% de las crisis y en el 27% las crisis desaparecieron totalmente. También se comunicaron cambios neurocognitivos: en el 73% hubo una mejoría del comportamiento; el 60% notificó una mejoría en el lenguaje; el 50%, en el sueño; el 43%, en la alimentación; y el 100%, en el estado de ánimo. La percepción global sobre la enfermedad notificó una mejoría en el 73%. Los efectos adversos más frecuentes fueron somnolencia y fatiga. Conclusiones. Estos resultados sugieren un posible efecto beneficioso del cannabidiol sobre el control de las crisis y en la mejoría de ciertos aspectos neurocognitivos en pacientes con epilepsias refractarias (AU)

Introduction. Some epileptic syndromes are characterised by seizures that are difficult to control and are associated to delayed neuropsychomotor development, which results in a deterioration in the patient’s quality of life as well as in that of his or her family. Aim. To evaluate the use of cannabidiol as adjuvant therapy in patients with refractory epilepsies. Patients and methods. An observational study was conducted by means of a survey addressed to the patient’s caregiver. Data collected included information about the patient and the caregiver, changes observed in the seizures, neuropsychological effects, side effects and the family’s overall perception following the use of cannabidiol. Results. The evaluation examined 15 patients with refractory epilepsies, who received cannabidiol over a period ranging from one month to one year. The frequency of seizures decreased in 40% of the patients, 60% of the patients were seen to have control over 50% of their seizures and in 27% of them the seizures disappeared completely. Neurocognitive changes were also reported: behaviour improved in 73%; 60% reported an improvement in language; in 50% sleep improved; 43% reported improvements in eating habits; and 100% said their mood had improved. The overall perception of the illness was that there had been improvements in 73% of respondents. The most common side effects were drowsiness and fatigue. Conclusions. These results suggest a possible beneficial effect of cannabidiol on the control of seizures and on the improvement of certain neurocognitive aspects in patients with refractory epilepsies (AU)

Outcome of arterial ischemic stroke in children with heart disease.

Arterial ischemic strokes (AIS) are rare in childhood. Congenital and acquired heart diseases are one of the most important risk factors of AIS in children. OBJECTIVE: Study the outcome of children with heart disease that have suffered AIS and the factors that influence on prognosis. PATIENTS AND METHODS: We evaluated all children with heart disease who had suffered AIS between 2000 and 2014 in our hospital. RESULTS: Seventy-four children with heart disease suffered an arterial ischemic stroke. 20% of them died and 10% had new AIS during the study period. Fifty-two patients were evaluated an average of six years after AIS. According to the Paediatric Stroke Outcome Scale (PSOM), most of the patients had some degree of impairment, mainly in sensorimotor and in cognitive-behavioural areas. The modified Rankin scale (mRS) showed an unfavourable outcome in 70% of patients (including patients that have died). Upper limb was more functionally impaired than lower limb. Strokes in neonatal period and early life were associated with poor prognosis. Size of stroke, cortical and subcortical involvement and basal ganglia stroke were associated with an unfavourable outcome. Fever in the acute phase and hemiparesis at presentation were also poor prognostic factors. Epilepsy at time of evaluation was also associated with unfavourable outcome. On the other hand, a normal electroencephalogram was associated with favourable outcome. CONCLUSIONS: AIS in children with heart disease had an unfavourable outcome, with impairment in different areas. Epilepsy happened in one third of the patients.

Posibilidades de tratamiento en la atrofia espinal infantil / Possible treatments for infantile spinal atrophy

Se revisan los nuevos tratamientos de la atrofia muscular espinal (AME) producida por deleción del gen SMN1. Se describen las diferentes posibilidades de incrementar la proteína SMN, de su actividad y persistencia en el organismo. Fármacos neuroprotectores, como olesoxime y riluzol, y fármacos que actúan epigenéticamente, como inhibidores de histona deacetilasa, han mostrado cierto efecto positivo en fases preclínicas pero no han conseguido eficacia en los ensayos clínicos. Podrían proporcionar en un futuro un beneficio añadidos a otros fármacos modificadores genéticos. Los mayores cambios en estudios de modelos del ratón SMA y en fases clínicas se han encontrado con oligonucleótidos antisentido que modifican el splicing del gen SMN2, y se espera que mejoren en el futuro próximo. Recientemente se ha aprobado el nusinersen, un metoxietilo fosforotioato-oligonucleótido antisentido, para uso en pacientes con AME de tipo I una vez demostrada su eficacia en pacientes en el ensayo en fase 3. Se revisan los resultados de este fármaco. Están en marcha modificaciones de oligonucleótidos antisentido que amplíen la liberación en el sistema nervioso y en tejidos periféricos. Hay datos que sugieren eficacia de la terapia génica introduciendo el gen SMN1 mediante virus adenoasociados, actualmente en fase clínica 1. Una constante en estos nuevos tratamientos es que los resultados se optimizan en las etapas precoces de la enfermedad y, mejor aún, en estadio presintomático. Se subraya la importancia de los cuidados generales óptimos, especialmente nutricionales y respiratorios, para conseguir los mejores resultados con las nuevas terapias (AU)

The new treatments of spinal muscular atrophy (SMA) due by SMN1 gene deletions are reviewed. There are several ways to increase the protein SMN, its activity and persistence in the tissues. Neuroprotective drugs as olesoxime or riluzole, and drugs acting by epigenetic mechanisms, as histone deacetylase inhibitors, have shown positive effects in preclinical studies but no clear efficacy in clinical trials. They might give in the future added benefits when used associated to other genetic modifying drugs. The best improvements in murine models of SMA and in clinical trials have been reached with antisense oligonucleotides, drugs that modify the splicing of SMN2, and they are expected to get better in the near future. Nusinersen, a methoxi-ethyl phosphotioate antisense oligonucleotide has recently approved for treatment of patients with SMA type 1 after having proved its efficacy in clinical trial phase 3. The results of nusinersen are reviewed. New modifications of antisense oligonucleotides with better access to brain, spinal cord and peripheral tissues are on the way. There are data of the efficacy of the genetic therapy with SMN1 gene through adenoassociated virus, now in phase 1 trial. A constant feature of these new treatments is that the earlier the treatment, the best are the results, and they are even better in presymptomatic stage. The general standards of care, particularly nutrition and respiratory management are needed in order to reach optimal results with the new therapies (AU)

Guía clínica de la enfermedad de Pompe infantil / Clinical guidelines for infantile-onset Pompe disease

La enfermedad de Pompe infantil tiene un pronóstico fatal a corto plazo si no se diagnostica precozmente ni se inicia un tratamiento enzimático sustitutivo lo antes posible. Un grupo de especialistas de las diferentes disciplinas involucradas en esta enfermedad ha revisado la evidencia científica actual y ha elaborado por consenso una serie de recomendaciones para el diagnóstico, el tratamiento y el seguimiento de los pacientes. Se recomienda instaurar tratamiento enzimático en todo paciente con enfermedad de Pompe sintomática de comienzo en el primer año de vida, con diagnóstico clínico y enzimático, y una vez conocido el estado CRIM (material inmunológico con reactividad cruzada) (AU)

Infantile-onset Pompe disease has a fatal prognosis in the short term unless it is diagnosed at an early stage and enzyme replacement therapy is not started as soon as possible. A group of specialists from different disciplines involved in this disease have reviewed the current scientific evidence and have drawn up an agreed series of recommendations on the diagnosis, treatment and follow-up of patients. We recommend establishing enzyme treatment in any patient with symptomatic Pompe disease with onset within the first year of life, with a clinical and enzymatic diagnosis, and once the CRIM (cross-reactive immunological material) status is known (AU)

Assessment of Targeted Next-Generation Sequencing as a Tool for the Diagnosis of Charcot-Marie-Tooth Disease and Hereditary Motor Neuropathy.

Charcot-Marie-Tooth disease is characterized by broad genetic heterogeneity with >50 known disease-associated genes. Mutations in some of these genes can cause a pure motor form of hereditary motor neuropathy, the genetics of which are poorly characterized. We designed a panel comprising 56 genes associated with Charcot-Marie-Tooth disease/hereditary motor neuropathy. We validated this diagnostic tool by first testing 11 patients with pathological mutations. A cohort of 33 affected subjects was selected for this study. The DNAJB2 c.352+1G>A mutation was detected in two cases; novel changes and/or variants with low frequency (<1%) were found in 12 cases. There were no candidate variants in 18 cases, and amplification failed for one sample. The DNAJB2 c.352+1G>A mutation was also detected in three additional families. On haplotype analysis, all of the patients from these five families shared the same haplotype; therefore, the DNAJB2 c.352+1G>A mutation may be a founder event. Our gene panel allowed us to perform a very rapid and cost-effective screening of genes involved in Charcot-Marie-Tooth disease/hereditary motor neuropathy. Our diagnostic strategy was robust in terms of both coverage and read depth for all of the genes and patient samples. These findings demonstrate the difficulty in achieving a definitive molecular diagnosis because of the complexity of interpreting new variants and the genetic heterogeneity that is associated with these neuropathies.

Mutations in the MORC2 gene cause axonal Charcot-Marie-Tooth disease.

Charcot-Marie-Tooth disease (CMT) is a complex disorder with wide genetic heterogeneity. Here we present a new axonal Charcot-Marie-Tooth disease form, associated with the gene microrchidia family CW-type zinc finger 2 (MORC2). Whole-exome sequencing in a family with autosomal dominant segregation identified the novel MORC2 p.R190W change in four patients. Further mutational screening in our axonal Charcot-Marie-Tooth disease clinical series detected two additional sporadic cases, one patient who also carried the same MORC2 p.R190W mutation and another patient that harboured a MORC2 p.S25L mutation. Genetic and in silico studies strongly supported the pathogenicity of these sequence variants. The phenotype was variable and included patients with congenital or infantile onset, as well as others whose symptoms started in the second decade. The patients with early onset developed a spinal muscular atrophy-like picture, whereas in the later onset cases, the initial symptoms were cramps, distal weakness and sensory impairment. Weakness and atrophy progressed in a random and asymmetric fashion and involved limb girdle muscles, leading to a severe incapacity in adulthood. Sensory loss was always prominent and proportional to disease severity. Electrophysiological studies were consistent with an asymmetric axonal motor and sensory neuropathy, while fasciculations and myokymia were recorded rather frequently by needle electromyography. Sural nerve biopsy revealed pronounced multifocal depletion of myelinated fibres with some regenerative clusters and occasional small onion bulbs. Morc2 is expressed in both axons and Schwann cells of mouse peripheral nerve. Different roles in biological processes have been described for MORC2. As the silencing of Charcot-Marie-Tooth disease genes have been associated with DNA damage response, it is tempting to speculate that a deregulation of this pathway may be linked to the axonal degeneration observed in MORC2 neuropathy, thus adding a new pathogenic mechanism to the long list of causes of Charcot-Marie-Tooth disease.

Guía para el seguimiento de la enfermedad de Pompe de inicio tardío / Guidelines for monitoring late-onset Pompe disease

Aunque el tratamiento con alglucosidasa alfa ha contribuido a mejorar el pronóstico de los pacientes con enfermedad de Pompe de inicio tardío, es necesario hacer un seguimiento periódico de la evolución de la enfermedad y de la eficacia del tratamiento. Por este motivo, un comité de expertos españoles ha elaborado una guía para el seguimiento de estos pacientes. El comité propone un modelo de pruebas de seguimiento para la enfermedad de Pompe de inicio tardío. En primer lugar, ha de valorarse el estado nutricional y la función deglutoria. En segundo lugar, y debido a la variabilidad del cuadro clínico, el comité recomienda el uso simultáneo de varias escalas que midan distintas funciones y pará- metros. De este modo, la fuerza muscular se evalúa con la escala del Medical Research Council; la función motora, con la prueba de la marcha en seis minutos y pruebas cronometradas; la discapacidad, con la escala de actividad específica de la enfermedad de Pompe construida según el análisis de Rasch; la función respiratoria, con la medida de la capacidad vital forzada y la saturación de oxígeno; y la fatiga, con la escala de intensidad de la fatiga. Por último, la seguridad y la tolerabilidad del tratamiento enzimático sustitutivo se controlan con el registro y tratamiento de los potenciales efectos adversos y la medición de los anticuerpos antialglucosidasa alfa. Se incluyen también diversas recomendaciones generales (AU)

Although treatment with alglucosidase alfa has helped improve the prognosis of patients with late-onset Pompe disease, both the development of the disease and the effectiveness of the treatment need to be monitored on a regular basis. This is the reason that has led a committee of Spanish experts to draw up a series of guidelines on how to follow up these patients. The committee proposes a model of follow-up tests for late-onset Pompe disease. First of all, the nutritional status and swallowing function must be evaluated. Second, and due to the variability of the clinical features, the committee recommends the simultaneous use of several scales to measure different functions and parameters. Thus, muscular force is assessed with the Medical Research Council scale; motor functioning, with the six-minute walk test and timed tests; disability, with the Rasch-built Pompe-specific Activity scale; respiratory functioning, with measurement of the forced vital capacity and oxygen saturation; and fatigue, with the fatigue intensity scale. Lastly, the safety and tolerability of enzyme replacement therapy are controlled by registering and treating the potential side effects and measurement of the anti-alglucosidase alfa antibodies. A number of different general recommendations are also included (AU)

[Guidelines for monitoring late-onset Pompe disease.Sociedad Española de Medicina Interna (SEMI), Sociedad Española de Neurología (SEN) y Sociedad Española de Neumología y CirugíaTorácica (SEPAR)]. / Guía para el seguimiento de la enfermedad de Pompe de inicio tardío.

Although treatment with alglucosidase alfa has helped improve the prognosis of patients with late-onset Pompe disease, both the development of the disease and the effectiveness of the treatment need to be monitored on a regular basis. This is the reason that has led a committee of Spanish experts to draw up a series of guidelines on how to follow up these patients. The committee proposes a model of follow-up tests for late-onset Pompe disease. First of all, the nutritional status and swallowing function must be evaluated. Second, and due to the variability of the clinical features, the committee recommends the simultaneous use of several scales to measure different functions and parameters. Thus, muscular force is assessed with the Medical Research Council scale; motor functioning, with the six-minute walk test and timed tests; disability, with the Rasch-built Pompe-specific Activity scale; respiratory functioning, with measurement of the forced vital capacity and oxygen saturation; and fatigue, with the fatigue intensity scale. Lastly, the safety and tolerability of enzyme replacement therapy are controlled by registering and treating the potential side effects and measurement of the anti-alglucosidase alfa antibodies. A number of different general recommendations are also included.

TITLE: Guia para el seguimiento de la enfermedad de Pompe de inicio tardio.Aunque el tratamiento con alglucosidasa alfa ha contribuido a mejorar el pronostico de los pacientes con enfermedad de Pompe de inicio tardio, es necesario hacer un seguimiento periodico de la evolucion de la enfermedad y de la eficacia del tratamiento. Por este motivo, un comite de expertos españoles ha elaborado una guia para el seguimiento de estos pacientes. El comite propone un modelo de pruebas de seguimiento para la enfermedad de Pompe de inicio tardio. En primer lugar, ha de valorarse el estado nutricional y la funcion deglutoria. En segundo lugar, y debido a la variabilidad del cuadro clinico, el comite recomienda el uso simultaneo de varias escalas que midan distintas funciones y parametros. De este modo, la fuerza muscular se evalua con la escala del Medical Research Council; la funcion motora, con la prueba de la marcha en seis minutos y pruebas cronometradas; la discapacidad, con la escala de actividad especifica de la enfermedad de Pompe construida segun el analisis de Rasch; la funcion respiratoria, con la medida de la capacidad vital forzada y la saturacion de oxigeno; y la fatiga, con la escala de intensidad de la fatiga. Por ultimo, la seguridad y la tolerabilidad del tratamiento enzimatico sustitutivo se controlan con el registro y tratamiento de los potenciales efectos adversos y la medicion de los anticuerpos antialglucosidasa alfa. Se incluyen tambien diversas recomendaciones generales.

Complexity of the Hereditary Motor and Sensory Neuropathies: Clinical and Cellular Characterization of the MPZ p.D90E Mutation.

Early-onset hereditary motor and sensory neuropathies are rare diseases representing a broad clinical and genetic spectrum. Without a notable familial history, the clinical diagnosis is complicated because acquired causes of peripheral neuropathy, such as inflammatory neuropathies, neuropathies with toxic causes, and nutritional deficiencies, must be considered. We examined the clinical, electrophysiological, and pathologic manifestations of a boy with an initial diagnosis of chronic inflammatory demyelinating polyneuropathy. The progression of the disease despite treatment led to a suspicion of hereditary motor and sensory neuropathy. Genetic testing revealed the presence of the MPZ p.D90E mutation in heterozygosis. To clarify the pathogenicity of this mutation and achieve a conclusive diagnosis, we investigated the MPZ p.D90E mutation through in silico and cellular approaches. This study broadens the clinical phenotype of hereditary motor and sensory neuropathy due to MPZ mutation and emphasises the difficulty of achieving an accurate genetic diagnosis in a sporadic patient to provide an appropriate pharmacologic treatment.

Funciones visuoespaciales y prematuridad / Visuospatial functions and prematurity

Durante la infancia, las funciones visuoespaciales son importantes en los procesos de aprendizaje y en el desarrollo del pensamiento abstracto. Diferentes estudios muestran que los niños prematuros o con bajo peso al nacer obtienen menores puntuaciones en los tests que valoran las funciones cognitivas, siendo estas diferencias más pronunciadas durante el primer año de vida. Con el tiempo, estas diferencias se van atenuando, pero persiste un retraso madurativo que afecta a la memoria de trabajo y a los procesos visuoespaciales. No está claro cuáles son los factores implicados en el desarrollo de estas funciones y qué factores pre o perinatales pueden interferir en su buen desarrollo, pero se han descrito diferencias anatómicas y fisiológicas entre el cerebro del niño pretérmino y el término que podrían explicar, en parte, alguna de estas alteraciones. La diferente vulnerabilidad selectiva a la hipoxia entre el cerebro inmaduro, en el que predominan las neuronas de la subplaca y los preoligodendrocitos, y el cerebro maduro del niño nacido a término determinan diferencias en el patrón de lesión por hipoxia con mayor afectación de la sustancia blanca periventricular en el niño pretérmino. Este patrón lesional conlleva una disfunción en los procesos atencionales y visuoespaciales debido a la mayor vulnerabilidad de las regiones que intervienen en la ruta dorsal del procesamiento visual (AU)

Visuospatial functions are very important in learning process and development of abstract thought during childhood. Several studies show that preterm and low birth weight infants obtain lower scores in test that assess cognitive functions, specially in the first year of life. These differences are attenuated over time, but a developmental delay that affects working memory and visuospatial process still persists. It is unclear what factors are involved in development of these functions, and pre- or perinatal factors may interfere with the proper conduct of the same, but have been described anatomical and physiological differences between the preterm and term brain that could explain somewhere in these alterations. The different selective vulnerability to hypoxia between immature brain in which preoligodendrocytes and subplate neurons predominate, and mature brain, determine differences in the pattern of injury from hypoxia with greater involvement of the periventricular white matter in preterm children. This lesional pattern leaves to a dysfunction in attentional and visuospatial process, due to the increased vulnerability of the regions involved in the dorsal pathway of visual processing (AU)

Neurofibromas plexiformes voluminosos de cuello en la neurofibromatosis tipo 1 / Voluminous plexiform neurofibromas of the neck region in neurofibromatosis 1

Objetivo. Presentar las características clínicas, de imagen y evolutivas de una serie de pacientes con neurofibromatosis tipo 1 que desarrollaron durante la infancia neurofibromas plexiformes voluminosos en el cuello (NFPVC). Pacientes y métodos. Nueve pacientes (cinco mujeres y cuatro varones) con edades entre 3 y 15 años en el momento del diagnóstico de los tumores, que podían extenderse también a la fosa posterior y a la zona torácica superior. El diagnóstico estuvo basado fundamentalmente en la clínica, la imagen y la histología. Resultados. Un tumor era intralaríngeo y causaba problemas respiratorios. Los otros ocho casos tenían su origen en varias raíces espinales de uno o de ambos lados y podían crecer también hacia el interior de la fosa posterior y de la región torácica en algunos pacientes, y desplazaban a las estructuras anatómicas vecinas, especialmente en tres casos, todos niñas, en las que el tumor creció hasta alcanzar gran volumen, especialmente por un lado, parándose el crecimiento entre los 11 y 12 años y no volviendo a crecer más tarde. Conclusiones. Los NFPVC son tumores histológicamente benignos. La extirpación es necesaria cuando están localizados en la laringe por los problemas respiratorios que causan, pero no en los de las otras regiones, pese a que el voluminoso tamaño que alcanzan en algunos casos puede causar exagerados desplazamientos de las estructuras vecinas. El estudio de nuestra serie parece indicar que al menos los tumores extralaríngeos sólo crecen hasta los 11-12 años. Puede ser recomendable retrasar la cirugía tanto como sea posible si no existe sintomatología aguda que la haga necesaria (AU)

Aim. To present the clinic, imaging and evolutive characteristics of a series of patients with neurofibromatosis 1 with voluminous plexiform neurofibromas in the neck (VPNFN) during childhood. Patients and methods. Nine patients (five females and four males) who were diagnosed as VPNFN at ages between 3 and 15 years. The VPNFN widespread to the posterior fossa or the upper thoracic region in some cases. The diagnosis was based on the clinical, imaging and histological findings. Results. One of the tumors was intralaryngeal and caused respiratory difficulties. The other eight patients had the origin of the tumor in several spinal roots of one or both sides and could growth to the posterior fossa and to the upper thoracic region in some cases with displacement of the surrounding organs, especially in three patients, all girls, in whom the tumor reached a voluminous size on one side, that was observed only until 10 to 11 years when the growth ceased. Conclusions. The VPNFN are histologically benign tumors. Those located in the larynx must be removed because of therespiratory problems, but it is not necessary in cases with other locations despite the voluminous size that can reach in some patients with great displacement of the surrounding organs. The analysis of the results of our series may demonstrate that al least the extralaryngeal tumors only grow to 11-12 years of age. This possibility may make recommendable to retard the surgical treatment as much as possible in cases that it is not necessary (AU)

[Voluminous plexiform neurofibromas of the neck region in neurofibromatosis 1]. / Neurofibromas plexiformes voluminosos de cuello en la neurofibromatosis tipo 1.

AIM. To present the clinic, imaging and evolutive characteristics of a series of patients with neurofibromatosis 1 with voluminous plexiform neurofibromas in the neck (VPNFN) during childhood. PATIENTS AND METHODS. Nine patients (five females and four males) who were diagnosed as VPNFN at ages between 3 and 15 years. The VPNFN widespread to the posterior fossa or the upper thoracic region in some cases. The diagnosis was based on the clinical, imaging and histological findings. RESULTS. One of the tumors was intralaryngeal and caused respiratory difficulties. The other eight patients had the origin of the tumor in several spinal roots of one or both sides and could growth to the posterior fossa and to the upper thoracic region in some cases with displacement of the surrounding organs, especially in three patients, all girls, in whom the tumor reached a voluminous size on one side, that was observed only until 10 to 11 years when the growth ceased. CONCLUSIONS. The VPNFN are histologically benign tumors. Those located in the larynx must be removed because of the respiratory problems, but it is not necessary in cases with other locations despite the voluminous size that can reach in some patients with great displacement of the surrounding organs. The analysis of the results of our series may demonstrate that al least the extralaryngeal tumors only grow to 11-12 years of age. This possibility may make recommendable to retard the surgical treatment as much as possible in cases that it is not necessary.

TITLE: Neurofibromas plexiformes voluminosos de cuello en la neurofibromatosis tipo 1.Objetivo. Presentar las caracteristicas clinicas, de imagen y evolutivas de una serie de pacientes con neurofibromatosis tipo 1 que desarrollaron durante la infancia neurofibromas plexiformes voluminosos en el cuello (NFPVC). Pacientes y metodos. Nueve pacientes (cinco mujeres y cuatro varones) con edades entre 3 y 15 años en el momento del diagnostico de los tumores, que podian extenderse tambien a la fosa posterior y a la zona toracica superior. El diagnostico estuvo basado fundamentalmente en la clinica, la imagen y la histologia. Resultados. Un tumor era intralaringeo y causaba problemas respiratorios. Los otros ocho casos tenian su origen en varias raices espinales de uno o de ambos lados y podian crecer tambien hacia el interior de la fosa posterior y de la region toracica en algunos pacientes, y desplazaban a las estructuras anatomicas vecinas, especialmente en tres casos, todos niñas, en las que el tumor crecio hasta alcanzar gran volumen, especialmente por un lado, parandose el crecimiento entre los 11 y 12 años y no volviendo a crecer mas tarde. Conclusiones. Los NFPVC son tumores histologicamente benignos. La extirpacion es necesaria cuando estan localizados en la laringe por los problemas respiratorios que causan, pero no en los de las otras regiones, pese a que el voluminoso tamaño que alcanzan en algunos casos puede causar exagerados desplazamientos de las estructuras vecinas. El estudio de nuestra serie parece indicar que al menos los tumores extralaringeos solo crecen hasta los 11-12 años. Puede ser recomendable retrasar la cirugia tanto como sea posible si no existe sintomatologia aguda que la haga necesaria.

Triple therapy with darbepoetin alfa, idebenone, and riboflavin in Friedreich's ataxia: an open-label trial.

Minimal objective evidence exists regarding management of Friedreich's ataxia (FRDA). Antioxidant and recombinant human erythropoietin therapies have been considered potential treatments to slow progression of FRDA in a small number of studies. The primary objective of the current study was to test the efficacy, safety, and tolerability of triple therapy-darbepoetin alfa, idebenone, and riboflavin-in FRDA in a clinical pilot study. Patients included in this study were nine females, 16 to 45 years of age (average 28 ± 8), diagnosed with FRDA with confirmed GAA repeat expansion mutations in the FXN gene and a GAA repeat ≥400 on the shorter allele. Patients had a baseline score between 8 and 28.5 (average 20.7 ± 8.3) on the scale for the assessment and rating of ataxia and 94.3 ± 27.2 g/m(2) in left ventricular mass index (LVMI). Patients had been treated with triple therapy with 150 µg darbepoetin alfa every 2 or 3 weeks, 10-20 mg/kg/day idebenone, and 10-15 mg/kg/day riboflavin for 32 ± 19.4 months (range of 8-56 months). Triple therapy was tolerated. Although not statistically significant, improvement of ataxia was observed during the first six 4-month periods of the study. Furthermore, a small decrease in disease progression during the first 2 years of treatment was observed. Long-term statistically nonsignificant improvement of LVMI and stability of the echocardiographic parameters could be considered. Triple therapy may slow disease progression of FRDA.

Clinical features of congenital myasthenic syndrome due to mutations in DPAGT1.

BACKGROUND: A newly defined congenital myasthenic syndrome (CMS) caused by DPAGT1 mutations has recently been reported. While many other CMS-associated proteins have discrete roles localised to the neuromuscular junction, DPAGT1 is ubiquitously expressed, modifying many proteins, and as such is an unexpected cause of isolated neuromuscular involvement. METHODS: We present detailed clinical characteristics of five patients with CMS caused by DPAGT1 mutations. RESULTS: Patients have prominent limb girdle weakness and minimal craniobulbar symptoms. Tubular aggregates on muscle biopsy are characteristic but may not be apparent on early biopsies. Typical myasthenic features such as pyridostigmine and 3, 4- diaminopyridine responsiveness, and decrement on repetitive nerve stimulation are present. CONCLUSIONS: These patients mimic myopathic disorders and are likely to be under-diagnosed. The descriptions here should facilitate recognition of this disorder. In particular minimal craniobulbar involvement and tubular aggregates on muscle biopsy help to distinguish DPAGT1 CMS from the majority of other forms of CMS. Patients with DPAGT1 CMS share similar clinical features with patients who have CMS caused by mutations in GFPT1, another recently identified CMS subtype.

Axonal neuropathy, long limbs and bumpy tongue: think of MEN2B.

INTRODUCTION: Multiple endocrine neoplasia type 2 (MEN 2) is an uncommon autosomal dominant cancer syndrome which can be associated with nerve conduction abnormalities. METHODS: A 14-year-old boy with a family history of consanguinity developed progressive gait clumsiness, pes cavus, hypotonia, and mucosal tumors of the lips and tongue since the age of 3 years. At age 11 years, he was diagnosed with an hereditary motor neuropathy (Charcot-Marie-Tooth syndrome). RESULTS: Physical examination revealed a Marfanoid habitus, mucocutaneous verrucous tumors, thyroid nodules, and cervical adenopathy. Genetic testing demonstrated the p.M918T mutation in the RET gene, and blood tests showed elevated levels of calcitonin. CONCLUSIONS: Clinical suspicion in MEN2 is crucial for early diagnosis and subsequent therapy. Mucosal neuroma and a Marfanoid habitus are especially useful. Other neurologic manifestations should not disguise the endocrine disorder, because early diagnosis and treatment of medullary thyroid carcinoma determines the prognosis.

Mutations in DPAGT1 cause a limb-girdle congenital myasthenic syndrome with tubular aggregates.

Congenital myasthenic syndromes are a heterogeneous group of inherited disorders that arise from impaired signal transmission at the neuromuscular synapse. They are characterized by fatigable muscle weakness. We performed whole-exome sequencing to determine the underlying defect in a group of individuals with an inherited limb-girdle pattern of myasthenic weakness. We identify DPAGT1 as a gene in which mutations cause a congenital myasthenic syndrome. We describe seven different mutations found in five individuals with DPAGT1 mutations. The affected individuals share a number of common clinical features, including involvement of proximal limb muscles, response to treatment with cholinesterase inhibitors and 3,4-diaminopyridine, and the presence of tubular aggregates in muscle biopsies. Analyses of motor endplates from two of the individuals demonstrate a severe reduction of endplate acetylcholine receptors. DPAGT1 is an essential enzyme catalyzing the first committed step of N-linked protein glycosylation. Our findings underscore the importance of N-linked protein glycosylation for proper functioning of the neuromuscular junction. Using the DPAGT1-specific inhibitor tunicamycin, we show that DPAGT1 is required for efficient glycosylation of acetylcholine-receptor subunits and for efficient export of acetylcholine receptors to the cell surface. We suggest that the primary pathogenic mechanism of DPAGT1 mutations is reduced levels of acetylcholine receptors at the endplate region. These individuals share clinical features similar to those of congenital myasthenic syndrome due to GFPT1 mutations, and their disorder might be part of a larger subgroup comprising the congenital myasthenic syndromes that result from defects in the N-linked glycosylation pathway and that manifest through impaired neuromuscular transmission.

[Treatment with antisense oligonucleotides in Duchenne's disease]. / Tratamiento con oligonucleotidos antisentido en la enfermedad de Duchenne.

In this paper I review the results of the treatments directed to modify the mRNA of dystrophin with the goal of converting the severe Duchenne type to the milder Becker muscular dystrophy. Antisense oligomers potential to modify Duchenne muscular dystrophy (DMD) gene expression and therapeutic strategies to induce ribosomal read-through of nonsense mutations (PTC124) are described. They are an important advance in the treatment of DMD, so far unspecific. Significant expression of new dystrophin is observed in biopsies of peripheral muscle, although the functional improvement is not so encouraging. New modification of chemistries are expected to improve the liberation, broad distribution in muscles, as well as their efficacy and safety enough to allow a positive chronic treatment of DMD.

Guía clínica de la enfermedad de Pompe de inicio tardío / Clinical guidelines for late-onset Pompe disease

Resumen. Hasta 2006, la enfermedad de Pompe o glucogenosis tipo II era una enfermedad incurable y con tratamiento meramente paliativo. El desarrollo de la terapia de sustitución con la enzima α-glucosidasa recombinante humana ha constituido el primer tratamiento específico para esta enfermedad. El objetivo de esta guía es servir de referencia en el manejo de la variedad de inicio tardío de la enfermedad de Pompe, es decir, la que aparece después del primer año de vida. En la guía, un grupo de expertos españoles hace recomendaciones específicas en cuanto a diagnóstico, seguimiento y tratamiento de esta enfermedad. En cuanto al diagnóstico, el método de la muestra en sangre seca es imprescindible como primer paso para el diagnóstico de la enfermedad de Pompe, y el diagnóstico de confirmación de la enfermedad de Pompe debe realizarse mediante un estudio de la actividad enzimática en muestra líquida en linfocitos aislados o mediante el análisis mutacional del gen de la alfa-glucosidasa. En cuanto al tratamiento de la enfermedad con terapia de sustitución enzimática, los expertos afirman que es eficaz en la mejoría o estabilización de la función motora y pulmonar, y debe iniciarse cuando aparezcan los síntomas atribuibles a la enfermedad de Pompe (AU)

Summary. Before 2006, Pompe disease or glycogenosis storage disease type II was an incurable disease whose treatment was merely palliative. The development of a recombinant human alpha-glucosidase enzymatic replacement therapy has become the first specific treatment for this illness. The aim of this guide is to serve as reference for the management of the late-onset Pompe disease, the type of Pompe disease that develops after one year of age. In the guide a group of Spanish experts make specific recommendations about diagnosis, follow-up and treatment of this illness. With regard to diagnosis, the dried blood spots method is essential as the first step for the diagnosis of Pompe disease. The confirmation of the diagnosis of Pompe disease must be made by means of an study of enzymatic activity in isolated lymphocytes or a mutation analysis of the alpha-glucosidase gene. With regard to treatment with enzymatic replacement therapy, the experts say that is effective improving or stabilizating the motor function and the respiratory function and it must be introduced when the first symptoms attributable to Pompe disease appear (AU)