Rapid Molecular Diagnosis of Genetically Inherited Neuromuscular Disorders Using Next-Generation Sequencing Technologies.

Neuromuscular diseases are genetically highly heterogeneous, and differential diagnosis can be challenging. Over a 3-year period, we prospectively analyzed 268 pediatric and adult patients with a suspected diagnosis of inherited neuromuscular disorder (INMD) using comprehensive gene-panel analysis and next-generation sequencing. The rate of diagnosis increased exponentially with the addition of genes to successive versions of the INMD panel, from 31% for the first iteration (278 genes) to 40% for the last (324 genes). The global mean diagnostic rate was 36% (97/268 patients), with a diagnostic turnaround time of 4-6 weeks. Most diagnoses corresponded to muscular dystrophies/myopathies (68.37%) and peripheral nerve diseases (22.45%). The most common causative genes, TTN, RYR1, and ANO5, accounted for almost 30% of the diagnosed cases. Finally, we evaluated the utility of the differential diagnosis tool Phenomizer, which established a correlation between the phenotype and molecular findings in 21% of the diagnosed patients. In summary, comprehensive gene-panel analysis of all genes implicated in neuromuscular diseases facilitates a rapid diagnosis and provides a high diagnostic yield.

Impact of COVID-19 in Immunosuppressed Children With Neuroimmunologic Disorders.

BACKGROUND AND OBJECTIVES: To investigate whether children receiving immunosuppressive therapies for neuroimmunologic disorders had (1) increased susceptibility to SARS-CoV2 infection or to develop more severe forms of COVID-19; (2) increased relapses or autoimmune complications if infected; and (3) changes in health care delivery during the pandemic. METHODS: Patients with and without immunosuppressive treatment were recruited to participate in a retrospective survey evaluating the period from March 14, 2020, to March 30, 2021. Demographics, clinical features, type of immunosuppressive treatment, suspected or confirmed COVID-19 in the patients or cohabitants, and changes in care delivery were recorded. RESULTS: One hundred fifty-three children were included: 84 (55%) female, median age 13 years (interquartile range [8-16] years), 79 (52%) on immunosuppressive treatment. COVID-19 was suspected or confirmed in 17 (11%) (all mild), with a frequency similar in patients with and without immunosuppressive treatment (11/79 [14%] vs 6/74 [8%], p = 0.3085). The frequency of neurologic relapses was similar in patients with (18%) and without (21%) COVID-19. Factors associated with COVID-19 included having cohabitants with COVID-19 (p < 0.001) and lower blood levels of vitamin D (p = 0.039). Return to face-to-face schooling or mask type did not influence the risk of infection, although 43(28%) children had contact with a classmate with COVID-19. Clinic visits changed from face to face to remote for 120 (79%) patients; 110 (92%) were satisfied with the change. DISCUSSION: In this cohort of children with neuroimmunologic disorders, the frequency of COVID-19 was low and not affected by immunosuppressive therapies. The main risk factors for developing COVID-19 were having cohabitants with COVID-19 and low vitamin D levels.

First female with Allan-Herndon-Dudley syndrome and partial deletion of X-inactivation center.

Allan-Herndon-Dudley is an X-linked recessive syndrome caused by pathogenic variants in the SLC16A2 gene. Clinical manifestations are a consequence of impaired thyroid metabolism and aberrant transport of thyroid hormones to the brain. Carrier females are generally asymptomatic and may show subtle symptoms of the disease. We describe a female with a complete Allan-Herndon-Dudley phenotype, carrying a de novo 543-kb deletion of the X chromosome. The deletion encompasses exon 1 of the SLC16A2 gene and JPX and FTX genes; it is known that the latter two genes participate in the X-inactivation process upregulating XIST gene expression. Subsequent studies in the patient demonstrated the preferential expression of the X chromosome with the JPX and FTX deletion.

New genotype-phenotype correlations in a large European cohort of patients with sarcoglycanopathy.

Sarcoglycanopathies comprise four subtypes of autosomal recessive limb-girdle muscular dystrophies (LGMDR3, LGMDR4, LGMDR5 and LGMDR6) that are caused, respectively, by mutations in the SGCA, SGCB, SGCG and SGCD genes. In 2016, several clinicians involved in the diagnosis, management and care of patients with LGMDR3-6 created a European Sarcoglycanopathy Consortium. The aim of the present study was to determine the clinical and genetic spectrum of a large cohort of patients with sarcoglycanopathy in Europe. This was an observational retrospective study. A total of 33 neuromuscular centres from 13 different European countries collected data of the genetically confirmed patients with sarcoglycanopathy followed-up at their centres. Demographic, genetic and clinical data were collected for this study. Data from 439 patients from 13 different countries were collected. Forty-three patients were not included in the analysis because of insufficient clinical information available. A total of 159 patients had a confirmed diagnosis of LGMDR3, 73 of LGMDR4, 157 of LGMDR5 and seven of LGMDR6. Patients with LGMDR3 had a later onset and slower progression of the disease. Cardiac involvement was most frequent in LGMDR4. Sixty per cent of LGMDR3 patients carried one of the following mutations, either in a homozygous or heterozygous state: c.229C>T, c.739G>A or c.850C>T. Similarly, the most common mutations in LMGDR5 patients were c.525delT or c.848G>A. In LGMDR4 patients the most frequent mutation was c.341C>T. We identified onset of symptoms before 10 years of age and residual protein expression lower than 30% as independent risk factors for losing ambulation before 18 years of age, in LGMDR3, LGMDR4 and LGMDR5 patients. This study reports clinical, genetic and protein data of a large European cohort of patients with sarcoglycanopathy. Improving our knowledge about these extremely rare autosomal recessive forms of LGMD was helped by a collaborative effort of neuromuscular centres across Europe. Our study provides important data on the genotype-phenotype correlation that is relevant for the design of natural history studies and upcoming interventional trials in sarcoglycanopathies.

Autosomal dominant distal myopathy with nemaline rods due to p.Glu197Asp mutation in ACTA1.

In a previous report of a new phenotype with predominant scapulo-humeral-peroneal-distal myopathy associated with the Glu197Asp mutation in ACTA1, muscle biopsies did not show nemaline rods, nor could nemaline rods formation be demonstrated in an exhaustive functional in vivo or in vitro study. However, muscle biopsy in members of our family, carrying a similar clinical phenotype of some members of the original family and the same ACTA1 mutation, revealed the presence of numerous nemaline rods, suggesting that there must be other factors that explain the absence of nemaline rods.

Clinical guide for the diagnosis and follow-up of myotonic dystrophy type 1, MD1 or Steinert's disease. / Guía clínica para el diagnóstico y seguimiento de la distrofia miotónica tipo 1, DM1 o enfermedad de Steinert.

BACKGROUND AND OBJECTIVES: Steinert's disease or myotonic dystrophy type 1 (MD1), (OMIM 160900), is the most prevalent myopathy in adults. It is a multisystemic disorder with dysfunction of virtually all organs and tissues and a great phenotypical variability, which implies that it has to be addressed by different specialities with experience in the disease. The knowledge of the disease and its management has changed dramatically in recent years. This guide tries to establish recommendations for the diagnosis, prognosis, follow-up and treatment of the complications of MD1. MATERIAL AND METHODS: Consensus guide developed through a multidisciplinary approach with a systematic literature review. Neurologists, pulmonologists, cardiologists, endocrinologists, neuropaediatricians and geneticists have participated in the guide. RECOMMENDATIONS: The genetic diagnosis should quantify the number of CTG repetitions. MD1 patients need cardiac and respiratory lifetime follow-up. Before any surgery under general anaesthesia, a respiratory evaluation must be done. Dysphagia must be screened periodically. Genetic counselling must be offered to patients and relatives. CONCLUSION: MD1 is a multisystemic disease that requires specialised multidisciplinary follow-up.

Hydrocephalus in pyridoxine-dependent epilepsy: New case and literature review.

INTRODUCTION: Pyridoxine-dependent epilepsy (PDE) is a rare disorder of the lysine metabolism, characterized by a pharmacoresistant epileptic encephalopathy that usually begins in the neonatal period. However, its phenotypic spectrum is wide and not limited to seizures. We report a new case of PDE who developed hydrocephalus, along with an exhaustive review of the literature. CASE REPORT: Our patient presented with seizures at 13 h of life. Antiepileptic drugs, vitamins and cofactors were required to achieve seizure control. Laboratory tests were congruent with PDE. She remained seizure-free until age five months, when seizures reappeared in the context of increasing head size and irritability. A cranial ultrasound showed hydrocephalus, for which she underwent ventriculoperitoneal shunting. DISCUSSION: Seven other patients with same features have been previously reported. Seizure onset occurred within the first 7 days in all patients. Most of the children developed hydrocephalus at 6-7 months of age. In 4 out of 7 a genetic mutation was identified, despite the accurate etiology of hydrocephalus was unknown in most of them. The case we report behaved similarly to the others previously described. We postulate that the pathogenesis of this complication could be related to the high expression of antiquitin in choroid plexus epithelium, where the cerebrospinal fluid is produced. CONCLUSIONS: patients with PDE should be closely monitored, since they may present severe complications. We highlight the development of hydrocephalus, an uncommon but potentially life-threatening problem reported in 8 patients up to present time.

[Stroke in paediatric patients with sickle-cell anaemia]. / Ictus en pacientes pediátricos con anemia falciforme.

INTRODUCTION: Sickle-cell anaemia is the severe homozygotic form of drepanocytosis, a genetic disorder that often occurs among black people and which is characterised by the production of haemoglobin S, chronic hemolytic anaemia and tissue ischaemia due to alterations in blood flow. A quarter of the patients presented neurological manifestations; 8-10% of children will have a stroke. AIM. To analyse the cases of stroke in children with sickle-cell anaemia in our centre. PATIENTS AND METHODS: We conducted a retrospective descriptive study of children with sickle-cell anaemia and stroke. RESULTS: Five patients (two Dominicans and three Guineans) with sickle-cell anaemia and stroke; one patient suffered two episodes of stroke. The mean age was 27 months. Five of the episodes were ischaemic infarctions. Stroke was the initial form of presentation of drepanocytosis on three occasions. Two of the strokes occurred within a context of pneumococcal meningitis. Four of the patients had previously reported fever. The initial clinical picture was hemiparesis in four cases. Mean haemoglobin on diagnosing the stroke was 6.5 g/dL. Transcranial ultrasound imaging revealed alterations in three patients and, in all the patients, magnetic resonance imaging revealed lesions, which were bilateral in half the cases. Following the stroke, a hypertransfusion regimen protocol was established and only one patient presented a new stroke. This same patient went on to develop moya-moya disease and was submitted to an indirect revascularisation; the patient progressed well, without presenting any new ischaemic events. CONCLUSIONS: Drepanocytosis is a disease that is emerging in our setting as a result of immigration. It should be suspected in cases of paediatric strokes associated to anaemia, above all in black children under the age of five who were not submitted to neonatal screening.

TITLE: Ictus en pacientes pediatricos con anemia falciforme.Introduccion. La anemia falciforme es la forma homocigota, grave, de drepanocitosis, un trastorno genetico, frecuente en raza negra, caracterizado por la produccion de hemoglobina S, anemia hemolitica cronica e isquemia tisular por alteracion del flujo sanguineo. Una cuarta parte de los pacientes presenta manifestaciones neurologicas; el 8-10% de los niños sufrira un ictus. Objetivo. Analizar los casos de ictus en niños con anemia falciforme en nuestro centro. Pacientes y metodos. Estudio descriptivo retrospectivo de niños con anemia falciforme e ictus. Resultados. Se recogieron cinco pacientes (dos dominicanos y tres guineanos) con anemia falciforme e ictus; un paciente sufrio dos episodios ictales. La edad media fue de 27 meses. Cinco episodios fueron infartos isquemicos. El ictus fue la forma de inicio de la drepanocitosis en tres ocasiones. Dos de los ictus ocurrieron en un contexto de meningitis neumococica. En cuatro pacientes hubo fiebre previa. La clinica inicial fue hemiparesia en cuatro casos. La hemoglobina media al diagnostico de ictus fue de 6,5 g/dL. En tres pacientes se hallaron alteraciones en la ecografia transcraneal y, en todos los pacientes, lesiones en la resonancia magnetica, que en la mitad eran bilaterales. Tras el ictus se inicio un protocolo de regimen hipertransfusional, y solo un paciente presento un nuevo ictus, que desarrollo un sindrome moya-moya y fue sometido a una revascularizacion indirecta, con buena evolucion, sin presentar nuevos eventos isquemicos posteriores. Conclusiones. La drepanocitosis es una enfermedad emergente en nuestro medio debido a la inmigracion. Debe sospecharse en ictus pediatricos asociados a anemia, sobre todo en menores de 5 años de raza negra no sometidos a cribado neonatal.

[Neurodevelopmental disorders as the presenting symptom of Duchenne's muscular dystrophy]. / Trastornos del neurodesarrollo como forma de presentación de la distrofia muscular de Duchenne.

TITLE: Trastornos del neurodesarrollo como forma de presentacion de la distrofia muscular de Duchenne.

[The use of the ketogenic diet as treatment for refractory epilepsy in the paediatric age]. / Experiencia en el tratamiento con dieta cetogenica de la epilepsia refractaria en la edad pediatrica.

INTRODUCTION: Between 23% and 25% of epileptic children are refractory to antiepileptic drugs. In recent times there has been a renewed interest in the ketogenic diet as treatment in these patients who are not candidates for other therapeutic options. AIMS. To evaluate the effectiveness and safety of treatment with the ketogenic diet in an important number of paediatric patients with refractory epilepsy in our centre and to determine whether the results obtained are consistent with others recently reported in the literature. PATIENTS AND METHODS: A retrospective review was conducted of the medical records of 41 children with refractory epilepsy treated with the ketogenic diet, mostly the Radcliffe II-type diet, between 1998 and 2011. Their median age on starting the diet was 3.92 years old. RESULTS: At six months after beginning the diet, the number of crises was reduced by at least 50% in 36.84% of the sample (10.53% of the children reached a 90% reduction and 5.26% no longer suffered crises). Around 50% of those in the youngest age group responded positively. Some tolerable, transient side effects were experienced by 58.54% of the patients, consisting mainly in high levels of cholesterol and constipation; no variations in the anthropomorphic parameters were observed. CONCLUSIONS: The ketogenic diet is a good therapeutic alternative in cases of refractory epilepsy in the paediatric age. Moreover, the younger the child is on starting on the diet, the more likely he or she is to gain benefits from it. In general it is well tolerated. Regular check-ups with supervision of these patients' nutrition are of great importance.

TITLE: Experiencia en el tratamiento con dieta cetogenica de la epilepsia refractaria en la edad pediatrica.Introduccion. El 23-25% de los niños epilepticos son refractarios a farmacos antiepilepticos. El interes por la dieta cetogenica como tratamiento en estos pacientes no candidatos a otras opciones terapeuticas ha resurgido ultimamente. Objetivo. Valorar la eficacia y seguridad del tratamiento con dieta cetogenica en un importante numero de pacientes pediatricos con epilepsia refractaria en nuestro centro y determinar si los resultados obtenidos corroboran otros de publicacion reciente. Pacientes y metodos. Se revisaron retrospectivamente las historias clinicas de 41 niños con epilepsia refractaria que fueron tratados con dieta cetogenica entre 1998 y 2011, la mayoria con dieta tipo Radcliffe II. La mediana de edad al inicio de la dieta fue de 3,92 años. Resultados. A los seis meses del inicio de la dieta se redujeron las crisis en al menos un 50% en un 36,84% de la muestra (el 10,53% de los niños alcanzo mas de un 90% de reduccion y un 5,26% quedo sin crisis). Aproximadamente un 50% por grupo de edad en los mas pequeños respondio de manera positiva. Un 58,54% de los pacientes presento algun efecto secundario, tolerable y transitorio, principalmente elevacion de los niveles de colesterol y estreñimiento, sin observarse variacion en los parametros antropometricos. Conclusiones. La dieta cetogenica supone una buena alternativa terapeutica en los casos de epilepsia refractaria en la edad pediatrica, con mayor probabilidad de beneficio cuanto menor sea la edad del niño al inicio de la dieta. En general, es bien tolerada. Son de gran importancia en estos pacientes las revisiones periodicas con control nutricional.

[Aicardi syndrome: retrospective study of a series of seven case reports]. / Sindrome de Aicardi: estudio retrospectivo de una serie de siete casos.

INTRODUCTION: The Aicardi syndrome is a disorder presumably X-linked dominant, classically defined by the triad of agenesis of the corpus callosum, chorioretinal lacunae and infantile spasms, with lethality in males. PATIENTS AND METHODS: Retrospective descriptive study of patients diagnosed with Aicardi syndrome over a period of 29 years in two tertiary pediatric hospitals. RESULTS: We found seven women that developed infantile spasms before 6 months of age, epileptic spasms persisting beyond infancy in two cases, a refractory symptomatic partial epilepsy in three patients, and well-controlled partial epilepsy in one girl. Six cases presented severe-profound mental retardation and moderate-severe in a girl. Two girls died at 2 and 6 years-old. In all patients neuroimaging studies showed agenesis of the corpus callosum, intracranial cysts and malformations of cortical development. Ophthalmological lesions were chorioretinal lacunae in seven cases, anophthalmia/microphthalmia in four girls and optic nerve coloboma in three patients. Other findings were congenital heart disease, costovertebral abnormalities, cervical lymphangioma and focal hypertrichosis. CONCLUSIONS: The Aicardi syndrome should be suspected in girls with infantile spasms and agenesis of the corpus callosum. It is necessary to rule out these ophthalmologic abnormalities, malformations of cortical development and intracranial cysts. The prognosis is poor due to its high mortality and its evolution to refractory epilepsy and profound mental retardation.

TITLE: Sindrome de Aicardi: estudio retrospectivo de una serie de siete casos.Introduccion. El sindrome de Aicardi es un trastorno presumiblemente dominante ligado al cromosoma X, que afecta en exclusiva a mujeres, clasicamente definido por la triada de agenesia del cuerpo calloso, lagunas coriorretinianas y espasmos infantiles, letal en varones en la vida intrauterina. Pacientes y metodos. Estudio descriptivo retrospectivo de pacientes diagnosticadas y seguidas hasta el final de la edad pediatrica de sindrome de Aicardi en dos hospitales universitarios durante un periodo de 29 años. Resultados. Encontramos siete niñas, todas desarrollaron espasmos infantiles antes de los 6 meses de edad. La evolucion fue a espasmos mas alla de la infancia (n = 2), a epilepsia parcial farmacorresistente (n = 3) y a epilepsia parcial bien controlada (n = 1). Seis casos presentaron retraso mental grave-profundo, y uno, moderado-grave. Fallecieron dos niñas a los 2 y 6 años. En todas, los estudios de neuroimagen mostraron agenesia del cuerpo calloso, quistes intracraneales y malformaciones del desarrollo cortical cerebral, ademas de lesiones oftalmologicas: lagunas coriorretinianas (n = 7), anoftalmia/microftalmia (n = 4) y coloboma del nervio optico (n = 3). Otros hallazgos fueron cardiopatia congenita, anomalias costovertebrales, linfangioma cervical e hipertricosis focal. Conclusiones. El sindrome de Aicardi debe sospecharse en niñas con espasmos infantiles y agenesia del cuerpo calloso. Deben descartarse en estas pacientes las alteraciones oftalmologicas, las anomalias de la migracion y organizacion neuronal y los quistes intracraneales. El pronostico es grave por su elevada morbimortalidad y por la frecuente evolucion a epilepsia refractaria y retraso mental grave.

Mirrored-self misidentification in a patient without dementia: evidence for right hemispheric and bifrontal damage.

Mirrored-self misidentification, often referred as the 'mirror sign', is a delusion characterized by the inability to recognize one's own reflected image, often associated with the intact capacity to recognize others in the mirror. It has been described mainly in moderate or severe dementia, especially Alzheimer's disease. In the few reported cases without global cognitive impairment, right hemispheric and frontal dysfunctions have been described. We report a 90-year-old man with abrupt onset of the mirror sign after a minor right hemispheric ischemic stroke. Neuropsychological testing revealed preserved cognitive capacities, except for mild to moderate impairment of visuospatial skills, suggesting right hemisphere dysfunction. Neuroimaging showed a small right dorsolateral frontal infarct, and bifrontal encephalomalacia, consistent with a past history of head trauma. Scattered ischemic white matter lesions in posterior periventricular regions were also seen. It seems that the mirror sign is a multifactorial phenomenon that usually requires right hemispheric dysfunction (perceptual abnormalities, loss of familiarity) and frontal damage (loss of judgement and inability to correct wrong beliefs). The right frontal dorsolateral prefrontal cortex seems to have a crucial role in self-recognition.