Whole-body muscle magnetic resonance imaging in inflammatory myopathy with mitochondrial pathology.

Introduction: Inflammatory myopathy with mitochondrial pathology (IM-Mito) is a rare condition described in a few case series, and it is not clear whether it is a specific disease or a variant of Inclusion Body Myositis (IBM). Radiological data of IM-Mito patients has only been evaluated in one study. Aim: To analyze whole-body muscle magnetic resonance imaging (MRI) features in patients with IM-Mito compared with individuals with IBM. Methods: Fourteen IM-Mito and ten IBM patients were included. IM-Mito was defined by endomysial inflammatory infiltrate, presence of at least 1% of Cytochrome C Oxidase negative fibers, and absence of rimmed vacuoles in muscle biopsy; and IBM was defined by the presence of dystrophic muscular abnormalities, endomysial inflammatory infiltrate, and rimmed vacuoles. Patients underwent clinical evaluation and whole-body muscle MRI to determine the presence of edema, and fatty infiltration in various muscles. Results: Muscle imaging abnormalities were asymmetric in most patients with IM-Mito and IBM. Muscles with the highest average degree of fatty infiltration in both conditions were the quadriceps and medial gastrocnemius. Most patients with IM-Mito and IBM showed imaging patterns of rectus femoris relatively spared compared to other quadriceps muscles. The flexor digitorum profundus was the most affected muscle of the upper limbs in both IBM and IM-Mito. Discussion: Although the results suggest some similarities in muscle imaging features between IM-Mito and IBM, there remains uncertainty whether these two conditions are part of the same clinical spectrum.

Effect of the COVID-19 pandemic on patients with inherited neuromuscular disorders.

BACKGROUND: The COVID-19 pandemic has brought substantial challenges for current practices in treating hereditary neuromuscular disorders (hNMDs). However, this infection has not been the only concern for these patients. Social distancing has compromised multidisciplinary assistance and physical activity, and has brought about several mental health issues. We presented a follow-up on 363 patients with hNMDs at a Brazilian tertiary center during the peak of the COVID-19 pandemic. OBJECTIVE: We aimed to show the frequency and severity of SARS-CoV-2 infection among hNMD patients and to demonstrate the effects of the pandemic on life habits, disease progression and multidisciplinary supportive care status. METHODS: Three hundred and sixty-three patients (58% male and 42% female) were followed for three months through three teleconsultations during the peak of the COVID-19 pandemic in Brazil. RESULTS: There were decreases in the numbers of patients who underwent physical, respiratory and speech therapies. For several patients, their appetite (33%) and sleep habits (25%) changed. Physical exercises and therapies were interrupted for most of the patients. They reported new onset/worsening of fatigue (17%), pain (17%), contractions (14%) and scoliosis (7%). Irritability and sleep, weight and appetite changes, and especially diminished appetite and weight loss, were more frequent in the group that reported disease worsening. There was a low COVID-19 contamination rate (0.8%), and all infected patients had a mild presentation. CONCLUSION: The isolation by itself was protective from a COVID-19 infection perspective. However, this isolation might also trigger a complex scenario with life habit changes that are associated with an unfavorable course for the NMD.

Inflammatory myopathies: an update for neurologists.

Idiopathic inflammatory myopathies (IIM) are a heterogenous group of treatable myopathies. Patients present mainly to the rheumatologist and neurologists, complaining of acute or subacute onset of proximal weakness. Extramuscular manifestations may occur, including involvement of the lungs, skin, and joints. Classically, the diagnosis used to be made based on the creatine kinase level increase, abnormalities in electroneuromyography and presence of inflammatory infiltrates in the muscle biopsy. Recently, the importance of autoantibodies has increased, and now they may be identified in more than half of IIM patients. The continuous clinicoseropathological improvement in IIM knowledge has changed the way we see these patients and how we classify them. In the past, only polymyositis, dermatomyositis and inclusion body myopathy were described. Currently, immune-mediated necrotizing myopathy, overlap myositis and antisynthetase syndrome have been considered the most common forms of IIM in clinical practice, increasing the spectrum of classification. Patients previously considered to have polymyositis, in fact have these other forms of seropositive IIM. In this article, we reviewed the new concepts of classification, a practical way to make the diagnosis and how to plan the treatment of patients suffering from IIM.

The Location of Disease-Causing DES Variants Determines the Severity of Phenotype and the Morphology of Sarcoplasmic Aggregates.

Desmin (DES) is the main intermediate muscle filament that connects myofibrils individually and with the nucleus, sarcolemma, and organelles. Pathogenic variants of DES cause desminopathy, a disorder affecting the heart and skeletal muscles. We aimed to analyze the clinical features, morphology, and distribution of desmin aggregates in skeletal muscle biopsies of patients with desminopathy and to correlate these findings with the type and location of disease-causing DES variants. This retrospective study included 30 patients from 20 families with molecularly confirmed desminopathy from 2 neuromuscular referral centers. We identified 2 distinct patterns of desmin aggregates: well-demarcated subsarcolemmal aggregates and diffuse aggregates with poorly delimited borders. Pathogenic variants located in the 1B segment and the tail domain of the desmin molecule are more likely to present with early-onset cardiomyopathy compared to patients with variants in other segments. All patients with mutations in the 1B segment had well-demarcated subsarcolemmal aggregates, but none of the patients with variants in other desmin segments showed such histological features. We suggest that variants located in the 1B segment lead to well-shaped subsarcolemmal desmin aggregation and cause disease with more frequent cardiac manifestations. These findings will facilitate early identification of patients with potentially severe cardiac syndromes.

Effect of the COVID-19 pandemic on patients with inherited neuromuscular disorders / Efeito da pandemia do COVID-19 em pacientes com doenças neuromusculares hereditárias

ABSTRACT Background The COVID-19 pandemic has brought substantial challenges for current practices in treating hereditary neuromuscular disorders (hNMDs). However, this infection has not been the only concern for these patients. Social distancing has compromised multidisciplinary assistance and physical activity, and has brought about several mental health issues. We presented a follow-up on 363 patients with hNMDs at a Brazilian tertiary center during the peak of the COVID-19 pandemic. Objective We aimed to show the frequency and severity of SARS-CoV-2 infection among hNMD patients and to demonstrate the effects of the pandemic on life habits, disease progression and multidisciplinary supportive care status. Methods Three hundred and sixty-three patients (58% male and 42% female) were followed for three months through three teleconsultations during the peak of the COVID-19 pandemic in Brazil. Results There were decreases in the numbers of patients who underwent physical, respiratory and speech therapies. For several patients, their appetite (33%) and sleep habits (25%) changed. Physical exercises and therapies were interrupted for most of the patients. They reported new onset/worsening of fatigue (17%), pain (17%), contractions (14%) and scoliosis (7%). Irritability and sleep, weight and appetite changes, and especially diminished appetite and weight loss, were more frequent in the group that reported disease worsening. There was a low COVID-19 contamination rate (0.8%), and all infected patients had a mild presentation. Conclusion The isolation by itself was protective from a COVID-19 infection perspective. However, this isolation might also trigger a complex scenario with life habit changes that are associated with an unfavorable course for the NMD.

RESUMO Antecedentes: A Pandemia por COVID-19 tem trazido desafios subtanciais para a prática clínica no tratamento das doenças neuromusculares hereditárias (DNMh). A infecção não tem sido a única preocupação para os pacientes. O distanciamento social tem comprometido a assistência multidisciplinar, atividade física e tem trazido problemas mentais em decorrência do próprio isolamento. Nós apresentamos aqui um seguimento de 363 pacientes com DNMh de um centro terciário Brasileiro durante o pico da Pandemia de Covid-19. Objetivos: Mostrar a frequência e gravidade da infecção por Sars-Cov-2 em pacientes com DNMh e demonstrar os efeitos da pandemia nos hábitos de vida, na progressão da doença e no cuidado multidisciplinary. Métodos Trezentos e sessenta e três pacientes (58% homens and 42% mulheres) foram acompanhados por 3 meses através de 3 teleconsultas durante o pico da Pandemia de Covid-19 no Brasil. Resultados Houve um decréscimo no número de pacientes que faziam terapia física, respiratória e fonoaudiológica. Em muitos pacientes, o apetite (33%) e hábitos do sono (25%) se alteraram. Exercícios físicos e terapias foram interrompidas pela maioria dos pacientes. Physical exercises and therapies were interrupted for most of the patients. Eles relataram piora ou aparecimento de fadiga (17%), dor (17%), retrações (14%), e escoliose (7%). Irritabilidade, mudanças no sono, peso e apetite, sendo principalmente diminuição do apetite e peso foram mais frequentemente encontrados em pacientes que apresentaram piora clinica da doença. Houve uma baixa taxa de contaminação por Covid-19 (0.8%), e todos os pacientes infectado apresentaram quadro clinico leve. Conclusão O isolamento por si só se mostrou protetor na perspectiva de infecção por Covid-19, mas pode desencadear um cenário complexo com mudanças nos hábitos de vida e curso desfavorável da doença de base.

Inflammatory myopathies: an update for neurologists / Miopatias inflamatórias: uma atualização para neurologistas

ABSTRACT Idiopathic inflammatory myopathies (IIM) are a heterogenous group of treatable myopathies. Patients present mainly to the rheumatologist and neurologists, complaining of acute or subacute onset of proximal weakness. Extramuscular manifestations may occur, including involvement of the lungs, skin, and joints. Classically, the diagnosis used to be made based on the creatine kinase level increase, abnormalities in electroneuromyography and presence of inflammatory infiltrates in the muscle biopsy. Recently, the importance of autoantibodies has increased, and now they may be identified in more than half of IIM patients. The continuous clinicoseropathological improvement in IIM knowledge has changed the way we see these patients and how we classify them. In the past, only polymyositis, dermatomyositis and inclusion body myopathy were described. Currently, immune-mediated necrotizing myopathy, overlap myositis and antisynthetase syndrome have been considered the most common forms of IIM in clinical practice, increasing the spectrum of classification. Patients previously considered to have polymyositis, in fact have these other forms of seropositive IIM. In this article, we reviewed the new concepts of classification, a practical way to make the diagnosis and how to plan the treatment of patients suffering from IIM.

RESUMO As miopatias inflamatórias idiopáticas (MII) são um grupo heterogêneo de miopatias tratáveis. Os pacientes procuram principalmente o reumatologista e o neurologista, queixando-se de início agudo ou subagudo de fraqueza proximal. Manifestações extramusculares podem ocorrer, incluindo envolvimento dos pulmões, pele e articulações. Classicamente, o diagnóstico era feito com base na elevação dos níveis de creatina quinase, anormalidades na eletroneuromiografia e presença de infiltrados inflamatórios na biópsia muscular. Recentemente, a importância dos autoanticorpos aumentou, e agora eles podem ser identificados em mais da metade dos pacientes com MII. A contínua melhora clínico-soropatológica no conhecimento do MII mudou a forma como vemos esses pacientes e como os classificamos. No passado, apenas polimiosite, dermatomiosite e miopatia por corpos de inclusão eram descritas. Atualmente, a miopatia necrosante imunomediada, a miosite de sobreposição e a síndrome antissintetase têm sido consideradas as formas mais comuns de MII na prática clínica, aumentando o espectro de classificação. Pacientes previamente considerados como portadores de polimiosite, na verdade, têm uma dessas outras formas de MII soropositivas. Neste artigo, revisamos os novos conceitos de classificação, uma forma prática de fazer o diagnóstico e como planejar o tratamento de pacientes que sofrem de MII.

A Novel Multisystem Proteinopathy Caused by a Missense ANXA11 Variant.

OBJECTIVE: Protein misfolding plays a central role not only in amyotrophic lateral sclerosis (ALS), but also in other conditions, such as frontotemporal dementia (FTD), inclusion body myopathy (hIBM) or Paget's disease of bone. The concept of multisystem proteinopathies (MSP) was created to account for those rare families that segregate at least 2 out of these 4 conditions in the same pedigree. The calcium-dependent phospholipid-binding protein annexin A11 was recently associated to ALS in European pedigrees. Herein, we describe in detail 3 Brazilian families presenting hIBM (isolated or in combination with ALS/FTD) caused by the novel p.D40Y change in the gene encoding annexin A11 (ANXA11). METHODS: We collected clinical, genetic, pathological and skeletal muscle imaging from 11 affected subjects. Neuroimaging was also obtained from 8 patients and 8 matched controls. RESULTS: Clinico-radiological phenotype of this novel hIBM reveals a slowly progressive predominant limb-girdle syndrome, but with frequent axial (ptosis/dropped head) and distal (medial gastrocnemius) involvement as well. Muscle pathology identified numerous rimmed vacuoles with positive annexin A11, TDP-43 and p62 inclusions, but no inflammation. Central nervous system was also involved: two patients had FTD, but diffusion tensor imaging uncovered multiple areas of cerebral white matter damage in the whole group (including the corticospinal tracts and frontal subcortical regions). INTERPRETATION: These findings expand the phenotypic spectrum related to ANXA11. This gene should be considered the cause of a novel multisystem proteinopathy (MSP type 6), rather than just ALS. ANN NEUROL 2021;90:239-252.

Motor unit number index (MUNIX) in children and adults with 5q-spinal muscular atrophy: Variability and clinical correlations.

Spinal muscular atrophy (SMA) is a motor neuron disease associated with progressive muscle weakness and motor disability. The motor unit number index (MUNIX) is a biomarker used to assess loss of motor units in later-onset SMA patients. Twenty SMA patients (SMA types 3 and 4), aged between 7 and 41 years, were clinically evaluated through the Hammersmith Motor Functional Scale Expanded and the Spinal Muscular Atrophy-Functional Rating Scale. The patients underwent compound motor action potential (CMAP) and MUNIX studies of the right abductor pollicis brevis, abductor digiti minimi and tibialis anterior (TA) muscles. Age-matched healthy controls (n = 20) were enrolled to obtain normative CMAP and MUNIX values from the same muscles. Compared to healthy controls, SMA patients showed significant reductions in MUNIX values among all muscles studied, whereas CMAP showed reductions only in the weaker muscles (abductor digiti minimi and TA). MUNIX variability was significantly higher in the SMA group than in the control group. MUNIX variability in TA correlated with CMAP variability. Motor functional scores correlated with TA MUNIX. The MUNIX study is feasible in later-onset SMA patients, and TA MUNIX values correlate with disease severity in patients with mild motor impairment.

Managing intrathecal administration of nusinersen in adolescents and adults with 5q-spinal muscular atrophy and previous spinal surgery.

BACKGROUND: Spinal muscular atrophy (SMA) is a neurodegenerative disease of lower motor neurons associated with frequent occurrence of spinal deformity. Nusinersen is an antisense oligonucleotide that increases SMN protein level and is administrated by frequent intrathecal lumbar injections. Thus, spinal deformities and previous spinal surgery are important challenges for drug delivery in SMA. OBJECTIVE: To report imaging methods used for Nusinersen injection in SMA patients. METHODS: Nusinersen injection procedures in SMA types 2 and 3 patients who had previous spinal surgery were analyzed retrospectively to describe the imaging and puncture procedures, as well as the occurrence of complications. RESULTS: Nine SMA patients (14 to 50 years old) underwent 57 lumbar punctures for nusinersen injection. Six patients had no interlaminar space available; in five of them, a transforaminal approach was used, and another one underwent a surgery to open a posterior bone window for the injections. Transforaminal puncture was performed using CT scan in three cases and fluoroscopy in the other two, with a similar success rate. One patient in the transforaminal group had post-procedure radiculitis, and another one had vagal reaction (hypotension). In three cases, with preserved interlaminar space, injections were performed by posterior interlaminar puncture, and only one adverse event was reported (post-puncture headache). CONCLUSION: In SMA patients with previous spinal surgery, the use of imaging-guided intervention is necessary for administering intrathecal nusinersen. Transforaminal technique is indicated in patients for whom the interlaminar space is not available, and injections should always be guided by either CT or fluoroscopy.

Electrophysiological study of neuromuscular junction in congenital myasthenic syndromes, congenital myopathies, and chronic progressive external ophthalmoplegia.

This study was designed to analyze the sensitivity, specificity, and accuracy of jitter parameters combined with repetitive nerve stimulation (RNS) in congenital myasthenic syndrome (CMS), chronic progressive external ophthalmoplegia (CPEO), and congenital myopathies (CM). Jitter was obtained with a concentric needle electrode during voluntary activation of the Orbicularis Oculi muscle in CMS (n = 21), CPEO (n = 20), and CM (n = 18) patients and in controls (n = 14). RNS (3 Hz) was performed in six different muscles for all patients (Abductor Digiti Minimi, Tibialis Anterior, upper Trapezius, Deltoideus, Orbicularis Oculi, and Nasalis). RNS was abnormal in 90.5% of CMS patients and in only one CM patient. Jitter was abnormal in 95.2% of CMS, 20% of CPEO, and 11.1% of CM patients. No patient with CPEO or CM presented a mean jitter higher than 53.6 µs or more than 30% abnormal individual jitter (> 45 µs). No patient with CPEO or CM and mild abnormal jitter values presented an abnormal decrement. Jitter and RNS assessment are valuable tools for diagnosing neuromuscular transmission abnormalities in CMS patients. A mean jitter value above 53.6 µs or the presence of more than 30% abnormal individual jitter (> 45 µs) strongly suggests CMS compared with CPEO and CM.

Neurological consultations and diagnoses in a large, dedicated COVID-19 university hospital.

BACKGROUND: More than one-third of COVID-19 patients present neurological symptoms ranging from anosmia to stroke and encephalopathy. Furthermore, pre-existing neurological conditions may require special treatment and may be associated with worse outcomes. Notwithstanding, the role of neurologists in COVID-19 is probably underrecognized. OBJECTIVE: The aim of this study was to report the reasons for requesting neurological consultations by internists and intensivists in a COVID-19-dedicated hospital. METHODS: This retrospective study was carried out at Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, Brazil, a 900-bed COVID-19 dedicated center (including 300 intensive care unit beds). COVID-19 diagnosis was confirmed by SARS-CoV-2-RT-PCR in nasal swabs. All inpatient neurology consultations between March 23rd and May 23rd, 2020 were analyzed. Neurologists performed the neurological exam, assessed all available data to diagnose the neurological condition, and requested additional tests deemed necessary. Difficult diagnoses were established in consensus meetings. After diagnosis, neurologists were involved in the treatment. RESULTS: Neurological consultations were requested for 89 out of 1,208 (7.4%) inpatient COVID admissions during that period. Main neurological diagnoses included: encephalopathy (44.4%), stroke (16.7%), previous neurological diseases (9.0%), seizures (9.0%), neuromuscular disorders (5.6%), other acute brain lesions (3.4%), and other mild nonspecific symptoms (11.2%). CONCLUSIONS: Most neurological consultations in a COVID-19-dedicated hospital were requested for severe conditions that could have an impact on the outcome. First-line doctors should be able to recognize neurological symptoms; neurologists are important members of the medical team in COVID-19 hospital care.

Neurological consultations and diagnoses in a large, dedicated COVID-19 university hospital / Consultas neurológicas e diagnósticos em um grande hospital universitário dedicado a COVID-19

ABSTRACT Background: More than one-third of COVID-19 patients present neurological symptoms ranging from anosmia to stroke and encephalopathy. Furthermore, pre-existing neurological conditions may require special treatment and may be associated with worse outcomes. Notwithstanding, the role of neurologists in COVID-19 is probably underrecognized. Objective: The aim of this study was to report the reasons for requesting neurological consultations by internists and intensivists in a COVID-19-dedicated hospital. Methods: This retrospective study was carried out at Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, Brazil, a 900-bed COVID-19 dedicated center (including 300 intensive care unit beds). COVID-19 diagnosis was confirmed by SARS-CoV-2-RT-PCR in nasal swabs. All inpatient neurology consultations between March 23rd and May 23rd, 2020 were analyzed. Neurologists performed the neurological exam, assessed all available data to diagnose the neurological condition, and requested additional tests deemed necessary. Difficult diagnoses were established in consensus meetings. After diagnosis, neurologists were involved in the treatment. Results: Neurological consultations were requested for 89 out of 1,208 (7.4%) inpatient COVID admissions during that period. Main neurological diagnoses included: encephalopathy (44.4%), stroke (16.7%), previous neurological diseases (9.0%), seizures (9.0%), neuromuscular disorders (5.6%), other acute brain lesions (3.4%), and other mild nonspecific symptoms (11.2%). Conclusions: Most neurological consultations in a COVID-19-dedicated hospital were requested for severe conditions that could have an impact on the outcome. First-line doctors should be able to recognize neurological symptoms; neurologists are important members of the medical team in COVID-19 hospital care.

RESUMO Introdução: Mais de um terço dos pacientes com COVID-19 apresentam sintomas neurológicos que variam de anosmia a AVC e encefalopatia. Além disso, doenças neurológicas prévias podem exigir tratamento especial e estar associadas a piores desfechos. Não obstante, o papel dos neurologistas na COVID-19 é provavelmente pouco reconhecido. Objetivo: O objetivo deste estudo foi relatar os motivos para solicitar consultas neurológicas por clínicos e intensivistas em um hospital dedicado à COVID-19. Métodos: Estudo retrospectivo realizado no Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, Brasil, um centro dedicado à COVID-19 com 900 leitos (incluindo 300 leitos para unidades de terapia intensiva). O diagnóstico de COVID-19 foi confirmado por SARS-CoV-2-RT-PCR em swabs nasais. Todas as interconsultas de neurologia hospitalar entre 23 de março e 23 de maio de 2020 foram analisadas. Os neurologistas realizaram o exame neurológico, avaliaram todos os dados disponíveis para diagnosticar a patologia neurológica e solicitaram exames adicionais conforme necessidade. Diagnósticos difíceis foram estabelecidos em reuniões de consenso. Após o diagnóstico, os neurologistas participaram da condução dos casos. Resultados: Foram solicitadas consultas neurológicas para 89 de 1.208 (7,4%) em pacientes internados por COVID-19 durante o período. Os principais diagnósticos neurológicos incluíram: encefalopatia (44,4%), acidente vascular cerebral (16,7%), doenças neurológicas prévias (9,0%), crises epilépticas (9,0%), transtornos neuromusculares (5,6%), outras lesões encefálicas agudas (3,4%) e outros sintomas leves inespecíficos (11,2%). Conclusões: A maioria das consultas neurológicas em um hospital dedicado à COVID-19 foi solicitada para condições graves que poderiam afetar o desfecho clínico. Os médicos na linha de frente devem ser capazes de reconhecer sintomas neurológicos. Os neurologistas são membros importantes da equipe médica no atendimento hospitalar à COVID-19.

Facial myokymia in inherited peripheral nerve hyperexcitability syndrome.

Peripheral nerve hyperexcitability syndrome comprises a heterogeneous group of diseases, clinically characterised by myokymia, fasciculation, muscle cramps and stiffness. The causes are either immune mediated or non-immune mediated. Non-immune-mediated forms are mostly genetic, relating to two main genes: KCNQ2 and KCNA1 Patients with KCNQ2 gene mutations typically present with epileptic encephalopathy, benign familial neonatal seizures and myokymia, though occasionally with purely peripheral nerve hyperexcitability. We report a woman with marked facial myokymia and distal upper limb contractures whose mother also had subtle facial myokymia; both had the c.G620A (p.R207Q) variant in the KCNQ2 gene. Patients with familial myokymia and peripheral nerve hyperexcitability syndrome should be investigated for KCNQ2 variants. This autosomal dominant condition may respond to antiepileptic medications acting at potassium channels.

Clinical features of collagen VI-related dystrophies: A large Brazilian cohort.

OBJECTIVES: Collagen VI-related dystrophies (COL6-RDs) have a broad clinical spectrum and are caused by mutations in the COL6A1, COL6A2 and COL6A3 genes. Despite the clinical variability, two phenotypes are classically recognized: Bethlem myopathy (BM, milder form) and Ullrich congenital muscular dystrophy (UCMD, more severe form), with many patients presenting an intermediate phenotype. In this work, we present clinical and genetic data from 28 patients (27 families), aged 6-38 years (mean of 16.96 years), with COL6-RDs. PATIENTS AND METHODS: Clinical, muscle histology and genetic data are presented. COL6A1, COL6A2 and COL6A3 genes were analyzed by next-generation sequencing (NGS). RESULTS: Homozygous or heterozygous variants were found in COL6A1 (12 families), COL6A2 (12 families) and COL6A3 (3 families). Patients with the severe UCMD phenotype (three cases) had a homogeneous clinical picture characterized by neonatal onset of manifestations, no gait acquisition and a stable course, but with severe respiratory involvement. Most of the patients with the mild UCMD phenotype had neonatal onset of manifestations (88.8 %), delayed motor development (66.6 %), slowly progressive course, pulmonary involvement (55.5 %) and loss of the walking capacity before the age of 10 (66.6 %). In the intermediate group (nine patients), some children had neonatal onset of manifestations (44.5 %) and delayed motor development (88.9 %); but all of them achieved the ability to walk and were still ambulatory. Some patients that had the BM phenotype presented neonatal manifestations (57.1 %); however, all of them had normal motor development and normal pulmonary function. Only one patient from the group of BM lost the walking capacity during the evolution of the disease. Other frequent findings observed in all groups were joint retractions, spinal deformities, distal hyperextensibility, congenital hip dislocation and keloid formation. CONCLUSION: COL6-RDs present variable clinical manifestations, but common findings are helpful for the clinical suspicion. NGS is a valuable approach for diagnosis, providing useful information for the genetic counseling of families.