Gene replacement therapy for spinal muscular atrophy: safety and preliminary efficacy in a Brazilian cohort.

Spinal muscular atrophy (SMA) is a motor neuron disease associated with progressive muscle weakness, ventilatory failure, and reduced survival. Onasemnogene abeparvovec is the first gene replacement therapy (GT) approved to treat this condition. An observational retrospective study was conducted to assess adverse events and efficacy of GT in SMA patients. Forty-one patients with SMA (58.5% females and 80.1% SMA type 1) were included. The mean age at GT dosing was 18 (±6.4) months. Thirty-six patients (87.8%) were under previous treatment with nusinersen, and 10 (24.4%) continued nusinersen after GT. Mean CHOP-INTEND increased 13 points after 6 months and this finding did not differ between groups according to nusinersen maintenance after GT (p = 0.949). Among SMA type 1 patients, 14 (46.6%) reached the ability to sit alone. Liver transaminases elevation at least two times higher than the upper limit of normal value occurred in 29 (70.7%) patients. Thrombocytopenia occurred in 13 (31.7%) patients, and one presented thrombotic microangiopathy. Older age (>2 years) was associated with more prolonged use of corticosteroids (p = 0.021). GT is effective in SMA patients, combined nusinersen after GT did not appear to add gain in motor function and older age is associated with prolonged corticosteroid use.

Muscle Ultrasound Changes Correlate With Functional Impairment in Spinal Muscular Atrophy.

OBJECTIVE: We investigated ultrasound patterns of muscle involvement in different types of spinal muscular atrophy (SMA) and their correlation with functional status to determine the pattern of muscle compromise in patients with SMA and the potential role of ultrasound to evaluate disease progression. METHODS: We examined muscles (biceps brachii, rectus femoris, diaphragm, intercostals and thoracic multifidus) of 41 patients with SMA (types 1 to 4) and 46 healthy age- and sex-matched control individuals using B-mode ultrasound for gray-scale analysis (GSA), area (biceps brachii and rectus femoris) and diaphragm thickening ratio. Functional scales were applied to patients only. We analyzed ultrasound abnormalities in specific clinical subtypes and correlated findings with functional status. RESULTS: Compared with controls, patients had reduced muscle area and increased mean GSA for all muscles (p < 0.001), with an established correlation between the increase in GSA and the severity of SMA for biceps brachii, rectus femoris and intercostals (p = 0.03, 0.01 and 0.004 respectively) when using the Hammersmith Functional Motor Scale Expanded. Diaphragm thickening ratio was normal in the majority of patients, and intercostal muscles had higher GSA than diaphragm in relation to the controls. CONCLUSION: Ultrasound is useful for quantifying muscular changes in SMA and correlates with functional status. Diaphragm thickening ratio can be normal even with severe compromise of respiratory muscles in quantitative analysis, and intercostal muscles were more affected than diaphragm.

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.

Intragenic variants in the SMN1 gene determine the clinical phenotype in 5q spinal muscular atrophy.

OBJECTIVE: The aim of the study was to report the proportion of homozygous and compound heterozygous variants in the survival motor neuron 1 (SMN1) gene in a large population of patients with spinal muscular atrophy (SMA) and to correlate the severity of the disease with the presence of specific intragenic variants in SMN1 and with the SMN2 copy number. METHODS: Four hundred fifty Brazilian patients with SMA were included in a retrospective study, and clinical data were analyzed compared with genetic data; the SMN2 copy number was obtained by multiplex ligation-dependent probe amplification and pathogenic variants in SMN1 by next-generation sequencing. RESULTS: Four hundred two patients (89.3%) presented homozygous exon 7-SMN1 deletion, and 48 (10.7%) were compound heterozygous for the common deletion in one allele and a point mutation in the other allele. Recurrent variants in exons 3 and 6 (c.460C>T, c.770_780dup and c.734_735insC) accounted for almost 80% of compound heterozygous patients. Another recurrent pathogenic variant was c.5C>G at exon 1. Patients with c.770_780dup and c.734_735insC had a clinical phenotype correlated with SMN2 copy number, whereas the variants c.460C>T and c.5C>G determined a milder phenotype independently of the SMN2 copies. CONCLUSIONS: Patients with specific pathogenic variants (c.460C>T and c.5C>G) presented a milder phenotype, and the SMN2 copy number did not correlate with disease severity in this group.

Cognitive performance of children with spinal muscular atrophy: A systematic review.

Spinal muscular atrophy (SMA) is genetic and progressive, caused by large bi-allelic deletions in the SMN1 gene, or the association of a large deletion and a null variant. OBJECTIVE: To evaluate the evidence about cognitive outcomes in spinal muscular atrophy (SMA). METHODS: Searches on the PUBMED/Medline, Web of Knowledge and Scielo databases retrieved 26 studies (1989 to 2019, descriptors "spinal muscular atrophy" and "cognition"). Nine studies were selected according to the eligibility criteria: (1) cognition tested in individuals with SMA; (2) written in English or Spanish. The Risk of Bias in Non-Randomized Studies of Interventions was used to describe design, bias, participants, evaluation protocol and main findings. This study was registered on the International prospective register of systematic reviews (PROSPERO). RESULTS: Three studies described normal cognition. In another three studies, cognitive outcomes were above average. Cognitive impairment was found in three studies. Poor cognitive performance was more frequently reported in studies that were recent, included children with SMA type I and that employed visual/auditory attention and executive function tests. Protocols and cognitive domains varied, precluding metanalysis. CONCLUSION: The severity of motor impairment may be related to cognitive outcomes: studies that included a higher number/percentage of children with SMA type I found cognitive impairment. The establishment of gold-standard protocols is necessary. Further studies should compare the cognitive outcomes of subjects with SMA types I to IV.

A atrofia muscular espinhal (SMA) é genética e progressiva, causada por grandes deleções bi-alélicas no gene SMN1, ou pela associação de uma grande deleção e uma variante nula. OBJETIVO: Avaliar as evidências sobre o desempenho cognitivo na atrofia muscular espinhal (AME). MÉTODOS: Pesquisas nas bases de dados PUBMED/ Medline, Web of Knowledge e Scielo localizaram 26 estudos (1989 a 2019, descritores "atrofia muscular espinhal" e "cognição"). Nove estudos foram selecionados de acordo com os critérios de elegibilidade: (1) testaram a cognição em pessoas com AME; (2) escritos em inglês/espanhol. A avaliação do risco de viés em estudos com intervenções não-randomizadas foi utilizada para descrever o desenho experimental, viés, amostra, protocolo de avaliação e principais achados. Este estudo foi aprovado no Registro Internacional Prospectivo de Revisões Sistemáticas (PROSPERO). RESULTADOS: Em três estudos, foi registrado que a cognição estava preservada. Em três estudos, o desempenho cognitivo estava acima da média. O comprometimento cognitivo foi encontrado em três estudos. Desempenho cognitivo pobre foi mais frequentemente relatado em estudos recentes, estudos que incluíram crianças com AME tipo I e estudos que incluíram atenção visual/auditiva e testes de função executiva. Protocolos e domínios cognitivos variaram muito, portanto não foi possível a realização de metanálise. CONCLUSÃO: A gravidade do comprometimento motor pode estar relacionada ao desempenho cognitivo: estudos que incluíram maior número/porcentagem de crianças com AME tipo I encontraram alterações no desempenho cognitivo. O estabelecimento de protocolos padrão-ouro é necessário. Novos estudos devem comparar o desempenho cognitivo de pessoas com AME tipos I a IV, ou seja, com diferenças no prognóstico e no desempenho motor.

Cognitive performance of children with spinal muscular atrophy: A systematic review / Desempenho cognitivo de crianças com atrofia muscular espinhal: uma revisão sistemática

ABSTRACT Spinal muscular atrophy (SMA) is genetic and progressive, caused by large bi-allelic deletions in the SMN1 gene, or the association of a large deletion and a null variant. Objective: To evaluate the evidence about cognitive outcomes in spinal muscular atrophy (SMA). Methods: Searches on the PUBMED/Medline, Web of Knowledge and Scielo databases retrieved 26 studies (1989 to 2019, descriptors "spinal muscular atrophy" and "cognition"). Nine studies were selected according to the eligibility criteria: (1) cognition tested in individuals with SMA; (2) written in English or Spanish. The Risk of Bias in Non-Randomized Studies of Interventions was used to describe design, bias, participants, evaluation protocol and main findings. This study was registered on the International prospective register of systematic reviews (PROSPERO). Results: Three studies described normal cognition. In another three studies, cognitive outcomes were above average. Cognitive impairment was found in three studies. Poor cognitive performance was more frequently reported in studies that were recent, included children with SMA type I and that employed visual/auditory attention and executive function tests. Protocols and cognitive domains varied, precluding metanalysis. Conclusion: The severity of motor impairment may be related to cognitive outcomes: studies that included a higher number/percentage of children with SMA type I found cognitive impairment. The establishment of gold-standard protocols is necessary. Further studies should compare the cognitive outcomes of subjects with SMA types I to IV.

RESUMO A atrofia muscular espinhal (SMA) é genética e progressiva, causada por grandes deleções bi-alélicas no gene SMN1, ou pela associação de uma grande deleção e uma variante nula. Objetivo: Avaliar as evidências sobre o desempenho cognitivo na atrofia muscular espinhal (AME). Métodos: Pesquisas nas bases de dados PUBMED/ Medline, Web of Knowledge e Scielo localizaram 26 estudos (1989 a 2019, descritores "atrofia muscular espinhal" e "cognição"). Nove estudos foram selecionados de acordo com os critérios de elegibilidade: (1) testaram a cognição em pessoas com AME; (2) escritos em inglês/espanhol. A avaliação do risco de viés em estudos com intervenções não-randomizadas foi utilizada para descrever o desenho experimental, viés, amostra, protocolo de avaliação e principais achados. Este estudo foi aprovado no Registro Internacional Prospectivo de Revisões Sistemáticas (PROSPERO). Resultados: Em três estudos, foi registrado que a cognição estava preservada. Em três estudos, o desempenho cognitivo estava acima da média. O comprometimento cognitivo foi encontrado em três estudos. Desempenho cognitivo pobre foi mais frequentemente relatado em estudos recentes, estudos que incluíram crianças com AME tipo I e estudos que incluíram atenção visual/auditiva e testes de função executiva. Protocolos e domínios cognitivos variaram muito, portanto não foi possível a realização de metanálise. Conclusão: A gravidade do comprometimento motor pode estar relacionada ao desempenho cognitivo: estudos que incluíram maior número/porcentagem de crianças com AME tipo I encontraram alterações no desempenho cognitivo. O estabelecimento de protocolos padrão-ouro é necessário. Novos estudos devem comparar o desempenho cognitivo de pessoas com AME tipos I a IV, ou seja, com diferenças no prognóstico e no desempenho motor.

Matching pairs difficulty in children with spinal muscular atrophy type I.

This study aimed to investigate the performance on pair-matching tasks in children with Spinal Muscular Atrophy type I (SMA-I) and the relationship between this performance and motor function, functional independence and quality of life. SMA-I (n = 12; 6.0 ± 2.3 yrs; 9 boys, 3 girls) and control sex-, age-matched children (n = 12; 6.2 ± 2.6 yrs) performed four pair-matching figure, number and letter tasks. The eye tracker detected eye movements. SMA-I children were assessed with CHOP INTEND, Pediatric Evaluation of Disability Inventory, and Pediatric Quality of Life Inventory. Analysis of variance showed that SMA-I children had a lower percentage of correct answers and longer timed performance compared to controls (p < 0.05). Pediatric Evaluation of Disability Inventory score (social function domain) was correlated to the percentage of correct answers on the pair-matching tasks on task 1 (r = 0.81; p = 0.001) and task 2 (r = 0.66; p = 0.020). Pair-matching performance of SMA-I children was poorer than the performance of control children. There was a relationship between pair-matching performance and social function. The restricted interaction with the environment, due to severe paralysis and poor verbal communication, is associated with cognitive difficulties in SMA-I children. The eye tracker was helpful in cognitive assessment of SMA-I children, who responded to the cognitive tests with eye movements.

Relação entre alinhamento postural e desempenho motor em crianças com paralisia cerebral / Relationship between postural alignment and motor performance in children with cerebral palsy

O objetivo deste estudo foi verificar se há correlação entre alinhamento postural e desempenho motor em crianças com paralisia cerebral (PC), além de compará-las com crianças de desenvolvimento motor típico. Participaram 14 crianças com PC tipo espástico, entre 4 e 12 anos, classificadas nos níveis III, IV e V no sistema de classificação de função motora ampla (GMFCS); e 20 com idades entre 4 e 8 anos e desenvolvimento motor adequado, que constituíram o grupo controle. Foi avaliado o alinhamento de lordose cervical e cifose torácica na postura sentada por meio de fotometria; o desempenho motor foi avaliado pelo índice de função motora ampla (Gross motor function measure, GMFM) apenas nas dimensões sentar (B) e ficar em pé (D). O subgrupo de PC nível III obteve maiores escores no GMFM do que o dos níveis IV e V, com diferença significativa nas dimensôes B (p=0,00) e D (p=0,016). Quanto ao alinhamento postural, os dois subgrupos de PC apresentaram menor angulação da lordose cervical do que o GC, com diferença significativa; também foram medidos ãngulos menores da cifose torácica nos subgrupos PC, sendo que o subgrupo dos níveis IV e V apresentou diferença significativa tanto em relação ao outro subgrupo PC quanto ao controle...

The purpose was to search for a correlation between postural alignment and motor performance of children with cerebral palsy (CP), and to compare them to typical development children. Twenty of these, aged 4 to 8 years old, formed the control group (CG); and 14 children with CP, aged 4 to 12 years old, were divided into two subgroups (level III, and levels IV and V) according to their classification by the Gross Motor Function Classification System. Cervical lordosis and thoracic kyphosis angles in sitting posture were assessed by photometry; motor performance was assessed at dimensions B (sitting) and D (standing) of the Gross motor function measure (GMFM). PC level III subgroup had higher GMFM scores than levels IV and V subgroup, with significant differences at the B (p=0.00) and D (p=0.016) dimensions. As to posture alignment...