Obstructive Sleep Apnea Treatment with Oral Appliance in a Myotonic Dystrophy Type I Subject: A Case Report.

Objective to report a myotonic dystrophy type 1 (MD1) subject with obstructive sleep apnea syndrome treated with oral appliance. Methods A review of individual's history and records, associated with a photographic register of all diagnostic methods and literature research about the topic were done. Final Statements This case depicts the therapeutical choices disposable to treat subjects with obstructive sleep apnea and DM1. Although considered an uncommon treatment, the oral appliances, if well indicated in adequately selected cases, can satisfactorily improve respiratory parameters, symptoms and quality of life.

Transcriptome Analysis Reveals Altered Inflammatory Pathway in an Inducible Glial Cell Model of Myotonic Dystrophy Type 1.

Myotonic dystrophy type 1 (DM1), the most frequent inherited muscular dystrophy in adults, is caused by the CTG repeat expansion in the 3'UTR of the DMPK gene. Mutant DMPK RNA accumulates in nuclear foci altering diverse cellular functions including alternative splicing regulation. DM1 is a multisystemic condition, with debilitating central nervous system alterations. Although a defective neuroglia communication has been described as a contributor of the brain pathology in DM1, the specific cellular and molecular events potentially affected in glia cells have not been totally recognized. Thus, to study the effects of DM1 mutation on glial physiology, in this work, we have established an inducible DM1 model derived from the MIO-M1 cell line expressing 648 CUG repeats. This new model recreated the molecular hallmarks of DM1 elicited by a toxic RNA gain-of-function mechanism: accumulation of RNA foci colocalized with MBNL proteins and dysregulation of alternative splicing. By applying a microarray whole-transcriptome approach, we identified several gene changes associated with DM1 mutation in MIO-M1 cells, including the immune mediators CXCL10, CCL5, CXCL8, TNFAIP3, and TNFRSF9, as well as the microRNAs miR-222, miR-448, among others, as potential regulators. A gene ontology enrichment analyses revealed that inflammation and immune response emerged as major cellular deregulated processes in the MIO-M1 DM1 cells. Our findings indicate the involvement of an altered immune response in glia cells, opening new windows for the study of glia as potential contributor of the CNS symptoms in DM1.

Oropharyngeal dysphagia in early stages of myotonic dystrophy type 1.

INTRODUCTION: Myotonic dystrophy type 1 (DM1) is a multisystemic disorder characterized mainly by skeletal muscle alterations. Although oropharyngeal dysphagia is a prominent clinical feature of DM1, it remains poorly studied in its early disease stages. METHODS: Dysphagia was investigated in 11 presymptomatic DM1 carriers, 14 patients with DM1 and 12 age-matched healthy controls, by using fiberoptic endoscopic evaluation of swallowing (FEES) and clinical scores. RESULTS: Scores for the FEES variables, delayed pharyngeal reflex, posterior pooling, and postswallow residue were significantly greater in patients with DM1 and in presymptomatic DM1 carriers than in healthy controls (P < 0.05); oropharyngeal dysfunction was more severe in patients than in presymptomatic carriers. Penetration/aspiration was found altered exclusively in patients with DM1 (P < 0.05). DISCUSSION: Swallowing dysfunction occurs in presymptomatic DM1 carriers. Timely diagnosis of dysphagia in preclinical stages of the disease will aid in the timely management of presymptomatic carriers, potentially preventing medical complications. Muscle Nerve, 2019.

Origin of the myotonic dystrophy type 1 mutation in Mexican population and influence of Amerindian ancestry on CTG repeat allelic distribution.

Myotonic dystrophy type 1 is caused by expansion of a CTG trinucleotide repeat situated in the DMPK gene. Worldwide genetic studies suggest a single or limited number of mutational events cause the disease. However, distribution of CTG alleles and disease incidence varies among ethnicities. Due to the great ethnic diversity of the Mexican population, the present study was aimed at analyzing the impact of different lineages in shaping the CTG-repeat allelic distribution in the contemporary Mexican-Mestizo population as well as to shed light on the DM1 ancestral origin. Distribution of CTG-repeat alleles was similar among Mestizo and Amerindian subpopulations with (CTG)11-13 being the most frequent alleles in both groups, which implies that Mexican-Mestizo allelic distribution has been modeled by Amerindian ancestry. We diagnosed a relatively high number of cases, consistent with the high frequency of large-normal alleles found in Mexican subpopulations. Haplotype analysis using various polymorphic-markers in proximity to DMPK gene indicates that a single founder mutation originates myotonic dystrophy type 1 in Mexico; however, Y-STR haplogroups data and the presence of pre-mutated and large normal alleles in Amerindians support the hypothesis that both European and Amerindian ancestral chromosomes might have introduced the disease to the Mexican population, which was further disseminated through mestizaje.

Myotonic dystrophy type 1: frequency of ophthalmologic findings / Distrofia miotônica tipo 1: frequência dos achados oftalmológicos

ABSTRACT The purpose of the study was to evaluate the frequency of ophthalmologic abnormalities in a cohort of myotonic dystrophy type 1 (DM1) patients and to correlate them with motor function. We reviewed the pathophysiology of cataract and low intraocular pressure (IOP). Method Patients were included after clinical and laboratory diagnosis and after signed informed consent. They were evaluated by Motor Function Measure scale, Portuguese version (MFM-P) and ophthalmic protocol. Results We evaluated 42 patients aged 17 to 64 years (mean 40.7 ± 12.5), 22 of which were men. IOP (n = 41) was reduced in all but one. We found cataract or positivity for surgery in 38 (90.48%) and ptosis in 23 (54.76%). These signs but not IOP were significantly correlated with severity of motor dysfunction. Abnormalities in ocular motility and stereopsis were observed. Conclusion Cataract and ptosis are frequent in DM1 and associated to motor dysfunction. Reduced IOP is also common, but appears not to be related with motor impairment.

RESUMO O objetivo do estudo foi avaliar a frequência das anormalidades oftalmológicas em uma coorte de pacientes com distrofia miotônica tipo 1 (DM1) correlacionando-as à função motora. Revisamos a fisiopatogenia da catarata e baixa pressão intraocular (PIO). Método Os pacientes foram incluídos após diagnóstico clínico-laboratorial de DM1. Aqueles que assinaram o termo de participação foram avaliados pela escala medida da função motora, versão em português (MFM-P) e protocolo oftalmológico. Resultados Avaliamos 42 pacientes de 17 a 64 anos (média 40,7 ± 12,5), 22 do sexo masculino. Encontramos catarata ou positividade de cirurgia em 38 (90,48%) e blefaroptose em 23 (54,76%) e esses sinais foram correlacionados significativamente à maior gravidade da disfunção motora. Baixa PIO também foi comum e não correlacionada à gravidade motora. Alterações da motilidade ocular e de estereopsia ocorreram. Conclusão Catarata e ptose palpebral são frequentes na DM1 e associadas à gravidade motora. Baixa PIO é comum e parece ser independente da evolução motora.

Distrofa miotónica congénita en una Unidad de Cuidados Intensivos Neonatales: serie de casos / Congenital myotonic dystrophy in a Neonatal Intensive Care Unit: case series

La distrofia miotónica de Steinert es una enfermedad multisistémica, autosómica dominante, con un amplio espectro de gravedad y manifestaciones clínicas. La forma más grave es aquella que se manifesta en el periodo neonatal, llamada distrofa miotónica congénita. Se destaca la hipotonía global al nacer y el compromiso de la función respiratoria. Las complicaciones son frecuentes, principalmente, retraso del desarrollo psicomotor, del crecimiento pondoestatural, difcultades alimentarias y constipación. Se asocia a un mal pronóstico, con una mortalidad global de hasta un 50% de los niños gravemente afectados. Presentamos cinco casos de distrofa miotónica congénita con el objetivo de describir manifestaciones clínicas, métodos diagnósticos, tratamiento y pronóstico. Los datos existentes en la literatura sobre el desarrollo psicomotor, complicaciones y pronóstico de los supervivientes con distrofa miotónica congénita son pocos. En nuestra serie de casos, las limitaciones psicomotoras presentadas son signifcativas.

Steinert myotonic dystrophy is a multisystemic disease, autosomal dominant, with a wide spectrum of severity and clinical manifestations. The most severe form is one that manifests in the neonatal period, called congenital myotonic dystrophy. This condition is distinguished by overall hypotonia at birth and respiratory function compromise. Complications are frequent, mainly psychomotor development delay, growth failure, food diffculties and constipation. It is associated with a poor prognosis, with an overall mortality of up to 50% of severely affected children. We present fve patients with congenital myotonic dystrophy in order to describe clinical manifestations, diagnosis, treatment and prognosis. Existing data in the literature on psychomotor development, complications and prognosis of survivors withcongenital myotonic dystrophy are scarce. In our case studies, we have found signifcant chronic psychomotor limitations.

Distrofa miotónica congénita en una Unidad de Cuidados Intensivos Neonatales: serie de casos / Congenital myotonic dystrophy in a Neonatal Intensive Care Unit: case series

La distrofia miotónica de Steinert es una enfermedad multisistémica, autosómica dominante, con un amplio espectro de gravedad y manifestaciones clínicas. La forma más grave es aquella que se manifesta en el periodo neonatal, llamada distrofa miotónica congénita. Se destaca la hipotonía global al nacer y el compromiso de la función respiratoria. Las complicaciones son frecuentes, principalmente, retraso del desarrollo psicomotor, del crecimiento pondoestatural, difcultades alimentarias y constipación. Se asocia a un mal pronóstico, con una mortalidad global de hasta un 50% de los niños gravemente afectados. Presentamos cinco casos de distrofa miotónica congénita con el objetivo de describir manifestaciones clínicas, métodos diagnósticos, tratamiento y pronóstico. Los datos existentes en la literatura sobre el desarrollo psicomotor, complicaciones y pronóstico de los supervivientes con distrofa miotónica congénita son pocos. En nuestra serie de casos, las limitaciones psicomotoras presentadas son signifcativas.(AU)

Steinert myotonic dystrophy is a multisystemic disease, autosomal dominant, with a wide spectrum of severity and clinical manifestations. The most severe form is one that manifests in the neonatal period, called congenital myotonic dystrophy. This condition is distinguished by overall hypotonia at birth and respiratory function compromise. Complications are frequent, mainly psychomotor development delay, growth failure, food diffculties and constipation. It is associated with a poor prognosis, with an overall mortality of up to 50% of severely affected children. We present fve patients with congenital myotonic dystrophy in order to describe clinical manifestations, diagnosis, treatment and prognosis. Existing data in the literature on psychomotor development, complications and prognosis of survivors withcongenital myotonic dystrophy are scarce. In our case studies, we have found signifcant chronic psychomotor limitations.(AU)

Treatment of sleep central apnea with non-invasive mechanical ventilation with 2 levels of positive pressure (bilevel) in a patient with myotonic dystrophy type 1.

We are reporting a case of a 29 year-old female with diagnosis of myotonic dystrophy type 1 (Steinert's disease) with excessive daytime sleepiness, muscle fatigue, snoring, frequent arousals, non-restorative sleep, and witnessed apneas. Pulmonary function tests revealed a mild decrease of forced vital capacity. Nocturnal polysomnography showed an increase of apnea/hypopnea index (85.9 events/h), mainly of central type (236), minimal oxygen saturation of 72%, and end-tidal carbon dioxide values that varied from 45 to 53 mmHg. Bi-level positive airway pressure titration was initiated at an inspiratory pressure (IPAP) of 8 and an expiratory pressure (EPAP) of 4 cm H2O. IPAP was then gradually increased to eliminate respiratory events and improve oxygen saturation. An IPAP of 12cm H20 and an EPAP of 4cm H2O eliminated all respiratory events, and the oxygen saturation remained above 90%. Bi-level positive airway pressure treatment at spontaneous/timed mode showed an improvement in snoring, apneas, and Epworth sleepiness scale decreased from 20 to 10. This case illustrates the beneficial effects of Bi-level positive airway pressure support in central sleep apnea syndrome of a patient with myotonic dystrophy type 1.