Genetic profile of Brazilian patients with LAMA2-related dystrophies.

LAMA2-related dystrophies (LAMA2-RD) constitute a rare neuromuscular disorder with a broad spectrum of phenotypic severity. Our understanding of the genotype-phenotype correlations in this condition remains incomplete, and reliable clinical data for clinical trial readiness is limited. In this retrospective study, we reviewed the genetic data and medical records of 114 LAMA2-RD patients enrolled at seven research centers in Brazil. We identified 58 different pathogenic variants, including 21 novel ones. Six variants were more prevalent and were present in 81.5% of the patients. Notably, the c.1255del, c.2049_2050del, c.3976 C>T, c.5234+1G>A, and c.4739dup variants were found in patients unable to walk and without cortical malformation. In contrast, the c.2461A>C variant was present in patients who could walk unassisted. Among ambulatory patients, missense variants were more prevalent (p < 0.0001). Although no specific hotspot regions existed in the LAMA2, 51% of point mutations were in the LN domain, and 88% of the missense variants were found within this domain. Functional analysis was performed in one intronic variant (c.4960-17C>A) and revealed an out-of-frame transcript, indicating that the variant creates a cryptic splicing site (AG). Our study has shed light on crucial phenotype-genotype correlations and provided valuable insights, particularly regarding the Latin American population.

Serum myostatin as a candidate disease severity and progression biomarker of spinal muscular atrophy.

The identification of biomarkers for spinal muscular atrophy is crucial for predicting disease progression, severity, and response to new disease-modifying therapies. This study aimed to investigate the role of serum levels of myostatin and follistatin as biomarkers for spinal muscular atrophy, considering muscle atrophy secondary to denervation as the main clinical manifestation of the disease. The study evaluated the differential gene expression of myostatin and follistatin in a lesional model of gastrocnemius denervation in mice, as well as in a meta-analysis of three datasets in transgenic mice models of spinal muscular atrophy, and in two studies involving humans with spinal muscular atrophy. Subsequently, a case-control study involving 27 spinal muscular atrophy patients and 27 controls was conducted, followed by a 12-month cohort study with 25 spinal muscular atrophy cases. Serum levels of myostatin and follistatin were analysed using enzyme-linked immunosorbent assay at a single centre in southern Brazil. Skeletal muscle gene expression of myostatin decreased and of follistatin increased following lesional muscle denervation in mice, consistent with findings in the spinal muscular atrophy transgenic mice meta-analysis and in the iliopsoas muscle of five patients with spinal muscular atrophy type 1. Median serum myostatin levels were significantly lower in spinal muscular atrophy patients (98 pg/mL; 5-157) compared to controls (412 pg/mL; 299-730) (P < 0.001). Lower myostatin levels were associated with greater disease severity based on clinician-rated outcomes (Rho = 0.493-0.812; P < 0.05). After 12 months, there was a further reduction in myostatin levels among spinal muscular atrophy cases (P = 0.021). Follistatin levels did not differ between cases and controls, and no significant changes were observed over time. The follistatin:myostatin ratio was significantly increased in spinal muscular atrophy subjects and inversely correlated with motor severity. Serum myostatin levels show promise as a novel biomarker for evaluating the severity and progression of spinal muscular atrophy. The decrease in myostatin levels and the subsequent favourable environment for muscle growth may be attributed to denervation caused by motor neuron dysfunction.

Consensus from the Brazilian Academy of Neurology for the diagnosis, genetic counseling, and use of disease-modifying therapies in 5q spinal muscular atrophy.

Spinal muscular atrophy linked to chromosome 5 (SMA-5q) is an autosomal recessive genetic disease caused by mutations in the SMN1. SMA-5q is characterized by progressive degeneration of the spinal cord and bulbar motor neurons, causing severe motor and respiratory impairment with reduced survival, especially in its more severe clinical forms. In recent years, highly effective disease-modifying therapies have emerged, either acting by regulating the splicing of exon 7 of the SMN2 gene or adding a copy of the SMN1 gene through gene therapy, providing a drastic change in the natural history of the disease. In this way, developing therapeutic guides and expert consensus becomes essential to direct the use of these therapies in clinical practice. This consensus, prepared by Brazilian experts, aimed to review the main available disease-modifying therapies, critically analyze the results of clinical studies, and provide recommendations for their use in clinical practice for patients with SMA-5q. This consensus also addresses aspects related to diagnosis, genetic counseling, and follow-up of patients under drug treatment. Thus, this consensus provides valuable information regarding the current management of SMA-5q, helping therapeutic decisions in clinical practice and promoting additional gains in outcomes.

Atrofia muscular espinhal ligada ao cromossomo 5 (AME-5q) é uma doença genética de herança autossômica recessiva causada por mutações no gene SMN1. A AME-5q cursa com degeneração progressiva dos motoneurônios medulares e bulbares, acarretando grave comprometimento motor e respiratório com redução da sobrevida, especialmente nas suas formas clínicas mais graves. Nos últimos anos, terapias modificadoras da doença altamente eficazes, ou que atuam regulando o splicing do exon 7 do gene SMN2 ou adicionando uma cópia do gene SMN1 via terapia gênica, têm surgido, proporcionando uma mudança drástica na história natural da doença. Dessa forma, o desenvolvimento de guias terapêuticos e de consensos de especialistas torna-se importante no sentido de direcionar o uso dessas terapias na prática clínica. Este consenso, preparado por especialistas brasileiros, teve como objetivos revisar as principais terapias modificadoras de doença disponíveis, analisar criticamente os resultados dos estudos clínicos dessas terapias e prover recomendações para seu uso na prática clínica para pacientes com AME-5q. Aspectos relativos ao diagnóstico, aconselhamento genético e seguimento dos pacientes em uso das terapias também são abordados nesse consenso. Assim, esse consenso promove valiosas informações a respeito do manejo atual da AME-5q auxiliando decisões terapêuticas na prática clínica e promovendo ganhos adicionais nos desfechos finais.

Co-Occurrence of Myotonic Dystrophy Type 1 and Limb-Girdle Muscular Dystrophy Type 2B: A Case Report.

Introduction: Myotonic dystrophy type 1 (DM1) is an autosomal dominant neuromuscular disease whose pattern of weakness is predominantly distal. Limb-girdle muscular dystrophy type 2B/R2-dysferlin-related (LGMD2B/R2) is another neuromuscular disease, which presents an autosomal recessive inheritance and is marked by proximal muscle weakness. Even if uncommon, comorbid inherited pathologies must be considered in cases of atypical presentations, especially in those with family history of consanguinity. Case Presentation: Herein, we report the unique case of a patient diagnosed with both DM1 and LGMD2B/R2: a 38-year-old woman in follow-up of DM1 in a neuromuscular disease service presenting prominent proximal weakness. The patient's parents were consanguineous, and creatine kinase levels were elevated. A multi-gene panel test was performed and revealed the diagnosis of LGMD2B/R2. Conclusion: Genetic diseases with atypical presentations should raise the possibility of a second disorder, prompting an appropriate investigation. Overlooking a second diagnosis can implicate in not offering adequate genetic counseling, support, or specific treatment.

Empowerment of genetic information by women at-risk of being carriers of Duchenne and Becker muscular dystrophies.

The emergence of therapies acting on specific molecular targets for Duchenne and Becker muscular dystrophies (DBMD) led to expanded access of diagnostic DMD analysis. However, it is unclear how much of these advances have also improved healthcare and access to genetic testing for women at-risk of being carriers. This study evaluates the process of genetic counseling and empowerment of genetic information by women from DBMD families. We carried out a cross-sectional study between February and June 2022 in Brazil. The online survey with items regarding sociodemographic data; family history; access to health services; reproductive decisions; and the Genomic Outcome Scale was answered by 123 women recruited from a rare diseases reference service and a nationwide patient advocacy group. Genetic counseling was reported by 77/123 (62.6%) of women and 53.7% reported having performed genetic analysis of DMD. Although the majority knew about the risks for carriers of developing heart disease and muscle weakness, only 35% of potential carriers have had cardiac studies performed at least once in their lives. Country region, type of kinship, number of affected males in the family, age, notion of genetic risk, education level, and participation in advocacy groups were the main factors associated with adequate healthcare access to women and empowerment of genetic information. Education to health professionals and policies to expand access to carrier genetic testing, whether public policies or regulation of pharmaceutical companies' diagnostic programs, is paramount to improve the care of families with DBMD in Brazil.

Postural adjustments and perceptual responses of Nordic running: concurrent effects of poles and irregular terrain.

PURPOSE: In the natural environment, humans must continuously negotiate irregular and unpredictable terrain. Recently, the poles have been extensively used during trial running events. However, we know little about how humans adjust posture and bilateral coordination to use poles in irregular terrain. Here, we compared kinematics, bilateral coordination and perceptual responses between regular (compact dust) and irregular terrain (medium-length grass) during running at preferred speed with and without poles. METHODS: In this transversal observational study, thirteen young healthy adults (8 men; mean ± SD; age 29.1 ± 8.0 years, body mass 76.8 ± 11.4 kg; height 1.75 ± 0.08 m) were evaluated during running at a self-selected comfortable speed with and without poles on regular and irregular terrains. RESULTS: Our results show that, despite more flexed pattern on lower-limb joints at irregular terrain, the usage of poles was not enough to re-stabilize the bilateral coordination. Also, the perceived exertion was impaired adding poles to running, probably due to more complex movement pattern using poles in comparison to free running, and the invariance in the bilateral coordination. CONCLUSION: Besides the invariability of usage poles on bilateral coordination and lower-limb kinematics, the runners seem to prioritize postural stability over lower limb stiffness when running in medium-length grass given the larger range of ankle and knee motion observed in irregular terrain. Further investigations at rougher/hilly terrains will likely provide additional insights into the neuromotor control strategies used to maintain the stability and on perceptual responses using poles during running.

Static Balance in Hereditary Spastic Paraplegias: a Cross-sectional Study.

Motor and somatosensory pathway dysfunction due to degeneration of long tracts in hereditary spastic paraplegias (HSP) indicates that postural abnormalities may be a relevant disease feature. However, balance assessments have been underutilized to study these conditions. How does the static balance of individuals with HSP with eyes open and closed differ from healthy controls, and how does it relate to disease severity? This cross-sectional case-control study assessed the static balance of 17 subjects with genetically confirmed HSP and 17 healthy individuals, evaluating the center of pressure (COP) variables captured by a force platform. The root-mean-square of velocities and mean of displacements amplitudes in mediolateral and anteroposterior axes were correlated with disease severity. All COP parameters' performances were significantly impaired in HSP subjects compared to controls (p < 0.001 for all comparisons). COP with eyes open and closed differed for all variables within the HSP group, whereas in the control group, differences were observed only for anteroposterior velocity and amplitude. Spastic Paraplegia Rating Scale presented moderate direct correlations with the most COP variables (Rho = - 0.520 to - 0.736). HSP individuals presented significant postural instability with eyes open and to a greater extent with eyes closed, corroborating the clinical findings of somatosensorial and proprioceptive pathways dysfunction. The degrees of proprioceptive and motor impairments are mutually correlated, suggesting that similar pathophysiological mechanisms operate for the degeneration of these long tracts. COP parameters can be seen as disease severity biomarkers of HSP, and they should be assessed in future clinical trials.

Consensus from the Brazilian Academy of Neurology for the diagnosis, genetic counseling, and use of disease-modifying therapies in 5q spinal muscular atrophy / Consenso da Academia Brasileira de Neurologia para diagnóstico, aconselhamento genético e uso de terapias modificadoras na atrofia muscular espinhal 5q

Abstract Spinal muscular atrophy linked to chromosome 5 (SMA-5q) is an autosomal recessive genetic disease caused by mutations in the SMN1. SMA-5q is characterized by progressive degeneration of the spinal cord and bulbar motor neurons, causing severe motor and respiratory impairment with reduced survival, especially in its more severe clinical forms. In recent years, highly effective disease-modifying therapies have emerged, either acting by regulating the splicing of exon 7 of the SMN2 gene or adding a copy of the SMN1 gene through gene therapy, providing a drastic change in the natural history of the disease. In this way, developing therapeutic guides and expert consensus becomes essential to direct the use of these therapies in clinical practice. This consensus, prepared by Brazilian experts, aimed to review the main available disease-modifying therapies, critically analyze the results of clinical studies, and provide recommendations for their use in clinical practice for patients with SMA-5q. This consensus also addresses aspects related to diagnosis, genetic counseling, and follow-up of patients under drug treatment. Thus, this consensus provides valuable information regarding the current management of SMA-5q, helping therapeutic decisions in clinical practice and promoting additional gains in outcomes.

Resumo Atrofia muscular espinhal ligada ao cromossomo 5 (AME-5q) é uma doença genética de herança autossômica recessiva causada por mutações no gene SMN1. A AME-5q cursa com degeneração progressiva dos motoneurônios medulares e bulbares, acarretando grave comprometimento motor e respiratório com redução da sobrevida, especialmente nas suas formas clínicas mais graves. Nos últimos anos, terapias modificadoras da doença altamente eficazes, ou que atuam regulando o splicing do exon 7 do gene SMN2 ou adicionando uma cópia do gene SMN1 via terapia gênica, têm surgido, proporcionando uma mudança drástica na história natural da doença. Dessa forma, o desenvolvimento de guias terapêuticos e de consensos de especialistas torna-se importante no sentido de direcionar o uso dessas terapias na prática clínica. Este consenso, preparado por especialistas brasileiros, teve como objetivos revisar as principais terapias modificadoras de doença disponíveis, analisar criticamente os resultados dos estudos clínicos dessas terapias e prover recomendações para seu uso na prática clínica para pacientes com AME-5q. Aspectos relativos ao diagnóstico, aconselhamento genético e seguimento dos pacientes em uso das terapias também são abordados nesse consenso. Assim, esse consenso promove valiosas informações a respeito do manejo atual da AME-5q auxiliando decisões terapêuticas na prática clínica e promovendo ganhos adicionais nos desfechos finais.

Neonatal screening for spinal muscular atrophy: A pilot study in Brazil.

Spinal muscular atrophy (SMA) is considered one of the most common autosomal recessive disorders, with an estimated incidence of 1 in 10,000 live births. Testing for SMA has been recommended for inclusion in neonatal screening (NBS) panels since there are several therapies available and there is evidence of greater efficacy when introduced in the pre/early symptomatic phases. In Brazil, the National Neonatal Screening Program tests for six diseases, with a new law issued in 2021 stating that it should incorporate more diseases, including SMA. In the present study, dried blood spot (DBS) samples collected by the Reference Services of Neonatal Screening of RS and SP, to perform the conventional test were also screened for SMA, using real-time PCR, with SALSA MC002 technique. A total of 40,000 samples were analyzed, enabling the identification of four positive cases of SMA, that were confirmed by MLPA. Considering our sampling, Brazil seems to have an incidence comparable to the described in other regions. This work demonstrated that the use of the MC002 technique in samples routinely collected for the conventional NBS program is suitable to screen for SMA in our conditions and can be included in the expansion of the neonatal screening programs.

Oral Dantrolene Reduces Myalgia and Hyperckemia in a Child with RYR1-Related Exertional Myalgia/Rhabdomyolysis.

RYR1-related exertional myalgia/rhabdomyolysis (ERM) is an underrecognized condition, which can cause limiting muscle symptoms, and may account for more than one-third of undiagnosed rhabdomyolysis cases. Dantrolene has shown promising results in controlling muscle symptoms in individuals with ERM, however, its use in children remains poorly documented. This case report presents the successful treatment of a 5-year-old patient with ERM using oral dantrolene. The patient experienced notable improvements, including a reduction in the frequency and intensity of myalgia episodes, no hospitalizations due to rhabdomyolysis, a substantial decrease in creatine phosphokinase (CPK) levels, and enhanced performance on the 6-minute walk test. The use of dantrolene was well-tolerated, and no significant adverse effects were observed. This report adds to the existing evidence supporting the effectiveness of oral dantrolene in managing ERM, and, to the best of our knowledge, this is the first report of the use of dantrolene in a pediatric patient for controlling anesthesia-independent muscle symptoms.

Long-term progression of clinician-reported and gait performance outcomes in hereditary spastic paraplegias.

Introduction: Hereditary spastic paraplegias (HSPs) are a heterogeneous group of neurodegenerative diseases in which little is known about the most appropriate clinical outcome assessments (COAs) to capture disease progression. The objective of this study was to prospectively determine disease progression after 4.5 years of follow-up with different clinician-reported (ClinRO) and gait performance outcomes (PerFOs). Methods: Twenty-six HSP patients (15 SPG4, 5 SPG7, 4 SPG5, 2 SPG3A) participated in this single-center cohort study in which the ClinRO: Spastic Paraplegia Rating Scale; and the PerFOs: 10-meters walking test and timed-up and go (TUG), at self-selected and maximal walking speeds; Locomotor Rehabilitation Index; and 6-min walking test were performed at baseline and after 1.5 (18 patients) and 4.5 (13 patients) years. Results: In the 3-year interval between the second and third assessments, significant progressions were only found in PerFOs, while in the overall 4.5 years of follow-up, both PerFOs and ClinROs presented significant progressions. The progression slopes of COAs modeled according to the disease duration allowed the estimation of the annual progression of the outcomes and sample size estimations for future clinical trials of interventions with different effect sizes. TUG at maximal walking speed was the only COA capable of differentiating subjects with a worse compared to a stable/better impression of change and would require the smallest sample size if chosen as the primary endpoint of a clinical trial. Discussion: These findings indicate that both performance and clinician-reported outcomes can capture long-term progression of HSPs, with some PerFOs presenting greater sensitivity to change. The presented data are paramount for planning future disease-modifying and symptomatic therapy trials for this currently untreatable group of diseases.

Estimated costs for Duchenne muscular dystrophy care in Brazil.

BACKGROUND: The economic burden of rare diseases on health systems is still not widely measured, with the generation of accurate information about the costs with medical care for subjects with rare diseases being crucial when defining health policies. Duchenne Muscular Dystrophy (DMD) is the most common form of muscular dystrophy, with new technologies recently being studied for its management. Information about the costs related to the disease in Latin America is scarce, and the objective of this study is to evaluate the annual hospital, home care and transportation costs per patient with DMD treatment in Brazil. RESULTS: Data from 27 patients were included, the median annual cost per patient was R$ 17,121 (IQR R$ 6,786; 25,621). Home care expenditures accounted for 92% of the total costs, followed by hospital costs (6%) and transportation costs (2%). Medications and loss of family, and patient's productivity are among the most representative consumption items. When disease worsening due to loss of the ability to walk was incorporated to the analysis, it was shown that wheelchair users account for an incremental cost of 23% compared with non-wheelchair users. CONCLUSIONS: This is an original study in Latin America to measure DMD costs using the micro-costing technique. Generating accurate information about costs is crucial to provide health managers with information that could help establish more sustainable policies when deciding upon rare diseases in emerging countries.

Update of the Brazilian consensus recommendations on Duchenne muscular dystrophy.

In the last few decades, there have been considerable improvements in the diagnosis and care of Duchenne muscular dystrophy (DMD), the most common childhood muscular dystrophy. International guidelines have been published and recently reviewed. A group of Brazilian experts has developed a standard of care based on a literature review with evidence-based graded recommendations in a two-part publication. Implementing best practice management has helped change the natural history of this chronic progressive disorder, in which the life expectancy for children of the male sex in the past used to be very limited. Since the previous publication, diagnosis, steroid treatment, rehabilitation, and systemic care have gained more significant insights with new original work in certain fields. Furthermore, the development of new drugs is ongoing, and some interventions have been approved for use in certain countries. Therefore, we have identified the need to review the previous care recommendations for Brazilian patients with DMD. Our objective was to create an evidence-based document that is an update on our previous consensus on those topics.

Nas últimas décadas, houve progressos significativos no diagnóstico e no tratamento da distrofia muscular de Duchenne (DMD), considerada a distrofia muscular mais comum na infância. Diretrizes internacionais foram publicadas e revisadas recentemente. Um grupo de especialistas brasileiros desenvolveu um padrão de atendimento baseado em revisão de literatura, com recomendações graduadas pautadas em evidências compiladas em uma publicação dividida em duas partes. A implementação de melhores práticas de manejo ajudou a modificar a história natural desta doença crônica, progressiva, que, no passado, oferecia uma expectativa de vida muito limitada para crianças do sexo masculino. Desde a publicação desse consenso anterior, o diagnóstico, o tratamento com esteroides, a reabilitação e os cuidados sistêmicos ganharam novas possibilidades a partir da divulgação dos resultados de trabalhos originais em algumas dessas áreas. Além disso, as pesquisas e o desenvolvimento de novos fármacos estão em andamento, e algumas intervenções já foram aprovadas para uso em determinados países. Nesse contexto, identificamos a necessidade de rever as recomendações anteriores sobre o manejo dos pacientes brasileiros com DMD. Nosso objetivo principal foi elaborar uma atualização baseada em evidências sobre esses tópicos do consenso.

Update of the Brazilian consensus recommendations on Duchenne muscular dystrophy / Atualização das recomendações do consenso brasileiro para distrofia muscular de Duchenne

Abstract In the last few decades, there have been considerable improvements in the diagnosis and care of Duchenne muscular dystrophy (DMD), the most common childhood muscular dystrophy. International guidelines have been published and recently reviewed. A group of Brazilian experts has developed a standard of care based on a literature review with evidence-based graded recommendations in a two-part publication. Implementing best practice management has helped change the natural history of this chronic progressive disorder, in which the life expectancy for children of the male sex in the past used to be very limited. Since the previous publication, diagnosis, steroid treatment, rehabilitation, and systemic care have gained more significant insights with new original work in certain fields. Furthermore, the development of new drugs is ongoing, and some interventions have been approved for use in certain countries. Therefore, we have identified the need to review the previous care recommendations for Brazilian patients with DMD. Our objective was to create an evidence-based document that is an update on our previous consensus on those topics.

Resumo Nas últimas décadas, houve progressos significativos no diagnóstico e no tratamento da distrofia muscular de Duchenne (DMD), considerada a distrofia muscular mais comum na infância. Diretrizes internacionais foram publicadas e revisadas recentemente. Um grupo de especialistas brasileiros desenvolveu um padrão de atendimento baseado em revisão de literatura, com recomendações graduadas pautadas em evidências compiladas em uma publicação dividida em duas partes. A implementação de melhores práticas de manejo ajudou a modificar a história natural desta doença crônica, progressiva, que, no passado, oferecia uma expectativa de vida muito limitada para crianças do sexo masculino. Desde a publicação desse consenso anterior, o diagnóstico, o tratamento com esteroides, a reabilitação e os cuidados sistêmicos ganharam novas possibilidades a partir da divulgação dos resultados de trabalhos originais em algumas dessas áreas. Além disso, as pesquisas e o desenvolvimento de novos fármacos estão em andamento, e algumas intervenções já foram aprovadas para uso em determinados países. Nesse contexto, identificamos a necessidade de rever as recomendações anteriores sobre o manejo dos pacientes brasileiros com DMD. Nosso objetivo principal foi elaborar uma atualização baseada em evidências sobre esses tópicos do consenso.

Copy number variations in SPAST and ATL1 are rare among Brazilians.

Copy number variations (CNV) may represent a significant proportion of SPG4 and SPG3A diagnosis, the most frequent autosomal dominant subtypes of hereditary spastic paraplegias (HSP). We aimed to assess the frequency of CNVs in SPAST and ATL1 and to update the molecular epidemiology of HSP families in southern Brazil. A cohort study that included 95 Brazilian index cases with clinical suspicion of HSP was conducted between April 2011 and September 2022. Multiplex Ligation Dependent Probe Amplification (MLPA) was performed in 41 cases without defined diagnosis by different massive parallel sequencing techniques (MPS). Diagnosis was obtained in 57/95 (60%) index cases, 15/57 (26.3%) being SPG4. Most frequent autosomal recessive HSP subtypes were SPG7 followed by SPG11, SPG76 and cerebrotendinous xanthomatosis. No CNVs in SPAST and ATL1 were found. Copy number variations are rare among SPG4 and SPG3A families in Brazil. Considering the possibility of CNVs detection by specific algorithms with MPS data, we consider that this is likely the most cost-effective approach to investigate CNVs in these genes in low-risk populations, with MLPA being reserved as an orthogonal confirmatory test.

Dysarthria in hereditary spastic paraplegia type 4.

OBJECTIVE: To describe the speech pattern of patients with hereditary Spastic Paraplegia type 4 (SPG4) and correlated it with their clinical data. METHODS: Cross-sectional study was carried out in two university hospitals in Brazil. Two groups participated in the study: the case group (n = 28) with a confirmed genetic diagnosis for SPG4 and a control group (n = 17) matched for sex and age. The speech assessment of both groups included: speech task recording, acoustic analysis, and auditory-perceptual analysis. In addition, disease severity was assessed with the Spastic Paraplegia Rating Scale (SPRS). RESULTS: In the auditory-perceptual analysis, 53.5% (n = 15) of individuals with SPG4 were dysarthric, with mild to moderate changes in the subsystems of phonation and articulation. On acoustic analysis, SPG4 subjects' performances were worse in measurements related to breathing (maximum phonation time) and articulation (speech rate, articulation rate). The articulation variables (speech rate, articulation rate) are related to the age of onset of the first motor symptom. CONCLUSION: Dysarthria in SPG4 is frequent and mild, and it did not evolve in conjunction with more advanced motor diseases. This data suggest that diagnosed patients should be screened and referred for speech therapy evaluation and those pathophysiological mechanisms of speech involvement may differ from the length-dependent degeneration of the corticospinal tract.

Dysarthria in hereditary spastic paraplegia type 4

Abstract Objective: To describe the speech pattern of patients with hereditary Spastic Paraplegia type 4 (SPG4) and correlated it with their clinical data. Methods: Cross-sectional study was carried out in two university hospitals in Brazil. Two groups participated in the study: the case group (n = 28) with a confirmed genetic diagnosis for SPG4 and a control group (n = 17) matched for sex and age. The speech assessment of both groups included: speech task recording, acoustic analysis, and auditory-perceptual analysis. In addition, disease severity was assessed with the Spastic Paraplegia Rating Scale (SPRS). Results: In the auditory-perceptual analysis, 53.5% (n = 15) of individuals with SPG4 were dysarthric, with mild to moderate changes in the subsystems of phonation and articulation. On acoustic analysis, SPG4 subjects' performances were worse in measurements related to breathing (maximum phonation time) and articulation (speech rate, articulation rate). The articulation variables (speech rate, articulation rate) are related to the age of onset of the first motor symptom. Conclusion: Dysarthria in SPG4 is frequent and mild, and it did not evolve in conjunction with more advanced motor diseases. This data suggest that diagnosed patients should be screened and referred for speech therapy evaluation and those pathophysiological mechanisms of speech involvement may differ from the length-dependent degeneration of the corticospinal tract.

Diagnostic reasoning in neurogenetics: a general approach.

Establishing the definitive diagnosis of a neurogenetic disease is usually a complex task. However, like any type of clinical diagnostic reasoning, an organized process of development and consideration of diagnostic hypotheses may guide neurologists and medical geneticists to solve this difficult task. The aim of the present review is to propose a general method for diagnostic reasoning in neurogenetics, with the definition of the main neurological syndrome and its associated topographical diagnosis, followed by the identification of major and secondary neurological syndromes, extraneurological findings, and inheritance pattern. We also discuss general rules and knowledge requirements of the ordering physician to request genetic testing and information on how to interpret genetic variants in a genetic report. By guiding the requests for genetic testing according to an organized model of diagnostic reasoning and with the availability of specific treatments, clinicians may find greater resoluteness and efficacy in the diagnostic investigation, shortening the struggle of patients for a definitive diagnosis.

Estabelecer o diagnóstico definitivo de uma condição neurogenética geralmente é uma tarefa complexa; entretanto, semelhante a qualquer raciocínio diagnóstico clínico, um processo organizado de formulação e ponderação de hipóteses diagnósticas pode ajudar neurologistas e médicos geneticistas a resolverem essa difícil tarefa. O objetivo desta revisão é propor um método geral de raciocínio diagnóstico em neurogenética, com a definição da síndrome neurológica principal e seu diagnóstico topográfico associado, seguidos da identificação das síndromes neurológicas principais e secundárias, dos achados extraneurológicos, e do padrão de herança. Também discutimos as regras gerais e os requisitos de conhecimento do médico solicitante para o pedido de teste genético e informações sobre como interpretar variantes genéticas quando recebemos um laudo. Ao orientar a solicitação de exames genéticos de acordo com um modelo organizado de raciocínio diagnóstico e com a disponibilidade de tratamentos específicos, o clínico poderá encontrar maior resolutividade e eficiência na investigação diagnóstica, o que encurtará a odisseia do paciente para um diagnóstico definitivo.

Diagnostic reasoning in neurogenetics: a general approach / Raciocínio diagnóstico em neurogenética: abordagem geral

Abstract Establishing the definitive diagnosis of a neurogenetic disease is usually a complex task. However, like any type of clinical diagnostic reasoning, an organized process of development and consideration of diagnostic hypotheses may guide neurologists and medical geneticists to solve this difficult task. The aim of the present review is to propose a general method for diagnostic reasoning in neurogenetics, with the definition of the main neurological syndrome and its associated topographical diagnosis, followed by the identification of major and secondary neurological syndromes, extraneurological findings, and inheritance pattern. We also discuss general rules and knowledge requirements of the ordering physician to request genetic testing and information on how to interpret genetic variants in a genetic report. By guiding the requests for genetic testing according to an organized model of diagnostic reasoning and with the availability of specific treatments, clinicians may find greater resoluteness and efficacy in the diagnostic investigation, shortening the struggle of patients for a definitive diagnosis.

Resumo Estabelecer o diagnóstico definitivo de uma condição neurogenética geralmente é uma tarefa complexa; entretanto, semelhante a qualquer raciocínio diagnóstico clínico, um processo organizado de formulação e ponderação de hipóteses diagnósticas pode ajudar neurologistas e médicos geneticistas a resolverem essa difícil tarefa. O objetivo desta revisão é propor um método geral de raciocínio diagnóstico em neurogenética, com a definição da síndrome neurológica principal e seu diagnóstico topográfico associado, seguidos da identificação das síndromes neurológicas principais e secundárias, dos achados extraneurológicos, e do padrão de herança. Também discutimos as regras gerais e os requisitos de conhecimento do médico solicitante para o pedido de teste genético e informações sobre como interpretar variantes genéticas quando recebemos um laudo. Ao orientar a solicitação de exames genéticos de acordo com um modelo organizado de raciocínio diagnóstico e com a disponibilidade de tratamentos específicos, o clínico poderá encontrar maior resolutividade e eficiência na investigação diagnóstica, o que encurtará a odisseia do paciente para um diagnóstico definitivo.

Speech and swallowing characteristics in patients with facioscapulohumeral muscular dystrophy / Caracterização da fala e da deglutição em pacientes com distrofia muscular facioescapuloumeral

ABSTRACT Background: Although facial muscle weakness is common in patients with Facioscapulohumeral Muscular Dystrophy (FSHD), the literature is scarce on the speech and swallowing aspects. Objective: To investigate speech and swallowing patterns in FSHD and assess the correlation with clinical data. Methods: A cross-sectional study was conducted. Patients with clinical confirmation of FSHD and aged above 18 years were included and paired with healthy control individuals by age and gender. Individuals who had neurological conditions that could interfere with test results were excluded. The following assessments were applied: speech tests (acoustic and auditory-perceptual analysis); swallowing tests with the Northwestern Dysphagia Patient Check Sheet (NDPCS), the Eat Assessment Tool (EAT-10), the Speech Therapy Protocol for Dysphagia Risk (PARD), and the Functional Oral Intake Scale (FOIS); disease staging using the modified Gardner-Medwin-Walton scale (GMWS); and quality of life with the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36). The correlation between test results and clinical data was verified by non-parametric statistics. Results: Thirteen individuals with FSHD and 10 healthy controls were evaluated. The groups presented significant differences in the motor bases of phonation and breathing. Regarding swallowing, two (15%) individuals presented mild dysphagia and seven (53.8%) showed reduced facial muscles strength. These results were not correlated with duration of the disease, age at symptoms onset, and quality of life. Dysphagia was related to worsening disease severity. Conclusions: FSHD patients presented mild dysarthria and dysphagia. Frequent monitoring of these symptoms could be an important way to provide early rehabilitation and better quality of life.

RESUMO Antecedentes: Embora haja predomínio de fraqueza muscular facial na distrofia facioescapuloumeral (FSHD), é escassa a literatura sobre aspectos de fala e deglutição. Objetivo: Investigar os padrões de fala e deglutição na FSHD e correlacioná-los com dados clínicos da doença. Métodos: Estudo transversal. Pacientes com confirmação clínica de FSHD e idade acima de 18 anos foram incluídos e pareados por idade e sexo com controles saudáveis. Foram excluídos indivíduos que apresentassem condições neurológicas que pudessem interferir nos resultados dos testes. Aplicaram-se as seguintes avaliações: fala (análise acústica e perceptivo-auditiva); deglutição, por meio do Northwestern Dysphagia Patient Check Sheet (NDPCS), Eat Assessment Tool (EAT-10), Protocolo de Avaliação para Risco de Disfagia (PARD) e Functional Oral Intake Scale (FOIS); estadiamento da doença, por meio da Gardner-Medwin-Walton scale (GMWS); e qualidade de vida, com o Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36). Resultados de fala e deglutição foram correlacionados com dados clínicos da doença por teste não paramétrico. Resultados: Foram avaliados 13 indivíduos com FSHD e dez controles saudáveis. Houve diferença significativa entre os grupos nas bases motoras fonação e respiração. Na deglutição, dois (15%) indivíduos apresentaram disfagia leve e sete (53,8%), força reduzida da musculatura da face. Esses resultados não foram correlacionados com tempo de doença, idade de início dos sintomas e qualidade de vida. A disfagia esteve relacionada com a gravidade da doença. Conclusões: Pacientes com FSHD apresentaram disartria e disfagia leves. O monitoramento frequente desses sintomas pode ser uma forma importante de proporcionar reabilitação precoce e melhor qualidade de vida.