Neuromuscular Centre Research Articles

Efficacy and safety of gene therapy with onasemnogene abeparvovec in children with spinal muscular atrophy in the D-A-CH-region: a population-based observational study

Real-world data on gene addition therapy (GAT) with onasemnogene abeparvovec (OA), including all age groups and with or without symptoms of the disease before treatment are needed to provide families with evidence-based advice and realistic therapeutic goals. Aim of this study is therefore a population-based analysis of all patients with SMA treated with OA across Germany, Austria and Switzerland (D-A-CH). This observational study included individuals with Spinal Muscular Atrophy (SMA) treated with OA in 29 specialized neuromuscular centers in the D-A-CH-region. A standardized data set including WHO gross motor milestones, SMA validated motor assessments, need for nutritional and respiratory support, and adverse events was collected using the SMArtCARE registry and the Swiss-Reg-NMD. Outcome data were analyzed using a prespecified statistical analysis plan including potential predictors such as age at GAT, SMN2 copy number, past treatment, and symptom status. 343 individuals with SMA (46% male, 54% female) with a mean age at OA of 14.0 months (range 0-90, IQR 20.0 months) were included in the analysis. 79 (23%) patients were clinically presymptomatic at the time of treatment. 172 (50%) patients received SMN2 splice-modifying drugs prior to GAT (risdiplam: n=16, nusinersen: n=154, both: n=2). Functional motor improvement correlated with lower age at GAT, with the best motor outcome in those younger than 6 weeks, carrying 3 SMN2 copies, and being clinically presymptomatic at time of treatment. The likelihood of requiring ventilation or nutritional support showed a significantly increase with older age at the time of GAT and remained stable thereafter. Pre-treatment had no effect on disease trajectories. Liver-related adverse events occurred significantly less frequently up to 8 months of age. All other adverse events showed an even distribution across all age and weight groups. Overall, motor, respiratory, and nutritional outcome were dependent on timing of GAT and initial symptom status. It was best in presymptomatic children treated within the first six weeks of life, but functional motor scores also increased significantly after treatment in all age groups up to 24 months. Additionally, OA was best tolerated when administered at a young age. Our study therefore highlights the need for SMA newborn screening and immediate treatment to achieve the best possible benefit-risk ratio. The SMArtCARE and Swiss-Reg-NMD registries are funded by different sources (see acknowledgements).

Clinical characteristics of idiopathic inflammatory myopathies related to anti-SRP: a single center experience

Idiopathic inflammatory myopathy (IIM) with autoantibodies recognizing the signal recognition particle (SRP) is characterized by prominent proximal weakness, infrequent extramuscular involvement, dramatically elevated creatine kinase levels, and myofiber necrosis with few inflammatory cell infiltrates in muscle tissue. To enhance understanding of the clinically used diagnosis and treatment of this disease, this study presents a single-center experience and analysis of a Chinese cohort with anti-SRP IIM. The most recent European Neuromuscular Center criteria were used to include Anti-SRP IIM patients from September 2016 to November 2019. Prior to treatment initiation, all sera were collected for the detection of anti-SRP autoantibodies and other myositis-related autoantibodies. Muscle strength, concurrent autoimmune conditions, comorbidities like interstitial lung disease (ILD), treatment outcomes, and follow-up results were also documented. Univariate logistic regression was employed to determine factors affecting prognosis. Among 271 patients with IIM, we identified 23 (8.5%) patients with anti-SRP IIM. Lower limb muscle weakness was frequently more severe. Interstitial lung disease (ILD) was observed in 50% of anti-SRP IIM patients. The presence of ILD may serve as a predictor of a poor prognosis, as revealed by univariate logistic regression analysis (odds ratio, 3.8, 95% CI: 1.0-6.8, p = 0.05).This Chinese Anti-SRP IIM cohort from Hunan province seems to have higher incidences of ILD, and associated ILD may be a risk factor for a poor prognosis. To fully understand the specific role of the anti-SRP autoantibody in this unique subset with ILD, further research is necessary.

Cross-cultural adaptation of the "Questionnaire about Care for People with Duchenne Muscular Dystrophy" to Brazilian Portuguese

Objective: To describe the cross-cultural adaptation of the"Questionnaire about Care for People with Duchenne MuscularDystrophy" to Brazilian Portuguese and our findings about the DMDcare access in a group of 43 patients assisted in an UniversityHospital in Rio de Janeiro.Method: Guidelines for best practice in translation and culturaladaptation were followed. Validation of the adapted questionnairewas verified in a group of 43 patients with Duchenne MuscularDystrophy (DMD) assisted in the Child Neurology Department of auniversity hospital in Rio de Janeiro.Results: Once the questionnaire was cross-adapted into BrazilianPortuguese, information was obtained on disease progression,access to recommended care and difficulties encountered inmaintaining treatment. This allowed comparison with previouslypublished national and international data.Conclusion: The adapted version of the CARE-NMD questionnairefor Brazilian Portuguese has the potential to support the work donein neuromuscular centers and health managers in Brazil. It providesa picture of access to care in our country, and allows exchangingupdated information between Brazilian and internationalneuromuscular centers.

Slowly progressing Amyotrophic lateral sclerosis associated with the F21L variant in the SOD1 gene: Demographic and clinical characteristics

Introduction/objective Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease in which genetic variants can significantly influence clinical presentation and prognosis. This study aims to describe the demographic and clinical characteristics of ALS patients carrying the SOD1: c.63C > G (p.Phe21Leu) [NM_000454.4] variant, as treated at a national reference center in Colombia. Methods A descriptive study was conducted on patients identified with the SOD1: c.63C > G (p.Phe21Leu) [NM_000454.4] variant, selected from the database of a neuromuscular disease center in Colombia. Demographic and clinical data were collected through medical records and patient interviews. Molecular analysis was performed using PCR and automated sequencing to confirm the presence of the variant. Results Eleven patients with SOD1: c.63C > G (p.Phe21Leu) [NM_000454.4] variant were identified. The mean age at onset was 48.4 years, with a mean disease duration of 76.7 months. The majority (90.9%) exhibited a slowly progressive course, predominantly with spinal onset and no cognitive impairment. Bulbar symptoms developed in 72.2% of the patients, and 81.8% required noninvasive ventilation. A family history of ALS or other neurodegenerative disorders was present in 54.5% of the patients. Conclusions The SOD1: c.63C > G (p.Phe21Leu) [NM_000454.4] variant is associated with a slowly progressive ALS phenotype, characterized by predominant lower motor neuron involvement and delayed onset of bulbar and respiratory symptoms. This variant appears to be predominantly distributed in central Colombia. Early detection of this variant may enable timely interventions and personalized care plans. Further research is required to establish a definitive causal relationship between this variant and the observed clinical course.

206P A quality improvement proposal: improving care management of complex neuromuscular patients – establishing a neuromuscular complex care centre as part of the translational neuromuscular pathway

206P A quality improvement proposal: improving care management of complex neuromuscular patients – establishing a neuromuscular complex care centre as part of the translational neuromuscular pathway

216P A questionnaire-based investigation into levels physical disability and of physical activity in adults with neuromuscular disease in a UK neuromuscular centre

216P A questionnaire-based investigation into levels physical disability and of physical activity in adults with neuromuscular disease in a UK neuromuscular centre

131P Social communication abilities in treated children with spinal muscular atrophy type 1 (SMA1): a cross-sectional study from two tertiary neuromuscular centres

131P Social communication abilities in treated children with spinal muscular atrophy type 1 (SMA1): a cross-sectional study from two tertiary neuromuscular centres

498P Neuromuscular centre effect on prevalence of congenital myasthenic syndrome (CMS) in the UK

498P Neuromuscular centre effect on prevalence of congenital myasthenic syndrome (CMS) in the UK

696P ADAPT-NMD: a hybrid II study exploring the feasibility of delivering, evaluating, and implementing a self-management programme for people with neuromuscular disorders at a specialist neuromuscular centre

696P ADAPT-NMD: a hybrid II study exploring the feasibility of delivering, evaluating, and implementing a self-management programme for people with neuromuscular disorders at a specialist neuromuscular centre

Impact of respiratory tract infections on spinal muscular atrophy with focus on respiratory syncytial virus infections: a single-centre cohort study.

Spinal muscular atrophy (SMA) is a degenerative neuromuscular disorder leading to muscle hypotonia, weakness, and respiratory and bulbar impairment. Infants with SMA have an increased risk of respiratory tract infections (RTI) including severe respiratory syncytial virus (RSV) infections. Therefore, guidelines for the treatment of SMA recommend RSV prophylaxis with palivizumab for patients aged below two years who have compromised motor functions ("non-sitters"). Since palivizumab is not approved for RSV prophylaxis in SMA patients in Switzerland, payers usually do not grant cost approvals for this indication. Therefore, this study aimed to investigate the frequency of severe RTI among SMA patients focusing on RSV infections requiring hospital treatment and to determine the long-term impact of RSV infections on the natural history of SMA. A single-centre cohort study at the tertiary paediatric Neuromuscular Centre Zurich, Switzerland, including data of SMA patients with a genetic-based therapy initiated below two years of age between May 2019 and December 2022. All hospitalisations were analysed with a focus on severe RTI and especially RSV infections, and their impact on nutritional and respiratory function. The costs of inpatient treatment of RSV infections were determined and compared with estimated expenses for RSV prophylaxis with palivizumab. 12 SMA patients (median age at treatment initiation: 3.5 months, range: 0-17 months) were followed for a cumulative period of 25.75 years (7 SMA type 1; 5 SMA type 2 including one presymptomatic individual). With an incidence rate of 2.34 per patient-year, the risk of severe RTI was especially high in SMA type 1 (versus 0.1 in SMA type 2, p = 0.044). A total of 37 hospitalisations (279 hospital days) was necessary for the treatment of RTI in general; 9 of them were attributed to RSV infections (in 5 SMA type 1 patients; 84 hospital days). Only 3/12 SMA patients had received seasonal RSV prophylaxis with palivizumab. No RSV infections requiring hospital treatment occurred in patients while receiving seasonal RSV prophylaxis. During RTI, nutritional support had to be commonly initiated and continued after discharge. In 3/7 SMA type 1 patients, non-invasive ventilation was started during acute treatment for RTI and continued to the end of follow-up. We observed a high risk of RTI, especially RSV infections, among young SMA patients. Failure to adhere to established care protocols, for example by omitting RSV prophylaxis, may be linked to a heightened risk of morbidity in these children.

450P A review of the symptom control clinic, advance care planning and mortality in myotonic dystrophy 1 in a UK neuromuscular centre

450P A review of the symptom control clinic, advance care planning and mortality in myotonic dystrophy 1 in a UK neuromuscular centre

Postnatal management of preterm infants with spinal muscular atrophy: experience from German newborn screening

BackgroundThe introduction of newborn screening (NBS) for spinal muscular atrophy (SMA) has increased the early diagnosis of 5q-associated SMA in presymptomatic and symptomatic preterm infants. National and international recommendations for treating preterms and newborns < 38 weeks of gestational age are unavailable. Our retrospective multicentre study aimed to evaluate the postnatal clinical course of preterm infants with 5q-associated SMA diagnosed since the implementation of NBS in Germany in 2021 and to summarize the German experience regarding the decision-making process for available treatment regimens for preterm infants with ≤ 3 survival of motor neuron 2 (SMN2) copies.ResultsTwelve preterm infants with 5q-associated SMA and a mean gestational age of 34.0 weeks (range: 26.1–36.8) and birth weight of 2022 g (range: 645–3370) were reported from 8/20 German SMA NBS follow-up centers using a pseudonymized questionnaire. Confirmatory diagnosis, including SMN2 copy number, was completed on average on postnatal day 13. All patients had a biallelic deletion of exon 7 or exons 7 and 8 of the survival of motor neuron 1 (SMN1) gene, with SMN2 copy numbers of two in 10 patients and three in two patients. The neonatal course was complicated by respiratory distress due to prematurity (n = 2), sepsis (n = 2), and jaundice (n = 2). At birth, 11 preterm infants (91.6%) were presymptomatic. However, the neurological status of one patient deteriorated at five weeks of age (postconceptional age of 41.8 weeks) prior to the start of treatment. Disease-modifying treatments were initiated in all patients at a mean postconceptional age of 38.8 weeks, with the majority receiving onasemnogene abeparvovec (83.3%, including 2 patients with prior risdiplam bridge therapy). Notably, consensus among participating experts from German neuromuscular centers resulted in 83.3% of patients receiving disease-modifying treatment at term.ConclusionsPremature infants with SMA require interdisciplinary care in close collaboration with the neuromuscular center. SMA NBS facilitates early initiation of disease-modifying therapy, ideally during the presymptomatic phase, which significantly influences the prognosis of the newborn.

Recommendations of an expert group for the cardiac assessment of non-dystrophic myotonia adult patients treated with mexiletine

Mexiletine (NaMuscla™) is indicated for the symptomatic treatment of myotonia in adults with non-dystrophic myotonia. A cardiac assessment is required as mexiletine may have a pro-arrhythmic effect. Long-term safety data supporting the use of mexiletine in patients with non-dystrophic myotonia combined with the extensive clinical experience of an expert group resulted in creation of an algorithm for cardiac monitoring of patients treated with mexiletine. To define the treatment algorithm, several expert workshops including three neurologists, five cardiologists from different French neuromuscular reference centers and one pharmacologist from Italy were set up. These workshops aimed to define the screening and surveillance tools required to ensure the safe use of mexiletine in patients. The recommendations are based on the summary of product characteristics (SmPC), a review of the literature on the safety of mexiletine-treated patients with non-dystrophic myotonia, and the expertise of the authors. The expert group concluded that the cardiac safety profile of mexiletine in these patients appears to be similar to that in the general population. Therefore, patients with non-dystrophic myotonia treated with mexiletine should be monitored as per any patient with cardiac problems who are prescribed a class 1b anti-arrhythmic.

Interpretation of Sydney Swallow Questionnaire results using the oropharyngeal dysphagia risk matrix.

Oropharyngeal dysphagia (OD) commonly occurs in neuromuscular diseases (NMD). Appropriate management involves early detection, clinical evaluation, and tailored follow-up to minimize complications. Various assessment tools exist, including the Sydney Swallow Questionnaire (SSQ), a patient-reported outcome measure for assessing OD severity in adult patients. This paper proposes utilizing an innovative risk matrix (OD-Risk-Matrix) to enhance SSQ interpretation. This matrix categorizes OD risk for each SSQ question, offering valuable assistance to clinicians. This study analyzes SSQ results from a cohort of individuals with NMD (n = 57). Patients filled in the SSQ during outpatient visits at our neuromuscular center. Subsequently, SSQ scores were grouped by NMD conditions and interpreted using the OD-Risk-Matrix categorizing each question's risk as low, moderate, or high. This matrix is based on the SSQ results by categorizing the risk of OD for each question, as well as the likelihood of occurrence of OD. In light of the OD-Risk-Matrix, the interpretation of SSQ scores revealed various risk categories associated with each question, while also highlighting distinct OD characteristics and discrepancies among the different NMDs. In conclusion, the OD-Risk-Matrix offers a framework for interpreting the SSQ, revealing variations in the risks of OD among different questions in patients with NMD. This novel approach could be a valuable tool in SSQ interpretation to identify specific fields of OD and could lead to a tailored management plan, prioritizing interventions aimed at reducing the risk of aspiration, ensuring proper nutrition, and enhancing swallowing safety and efficiency.

Guillain-Barrè Syndrome-Retrospective Analysis of Data from a Cohort of Patients Referred to a Tertiary Care Pediatric Neuromuscular Center from 2000 to 2017: Electrophysiological Findings, Outcomes, and a Brief Literature Review.

Background and Objectives: Guillain-Barré syndrome (GBS) is the most frequent cause of acute flaccid paresis in children. The aim of this study was to describe the clinical and electrophysiological findings and outcomes of children with GBS diagnosed in our unit. Moreover, the literature on pediatric GBS cases from the past 5 years was reviewed. In this retrospective study, we reported data on 12 patients (9 male and 3 female patients; mean age: 5 y, 4 mo; range: 9 mo-11 y) clinically diagnosed at the Child Neurology Unit of the AUSL-IRCCS of Reggio Emilia, Italy, between 2000 and 2017 and a brief analysis/comparison with data from the literature. Materials and Methods: Data were collected from medical charts. Results: In our cohort, male patients were more frequent than female ones (9 vs. 3), and upper respiratory tract infection (n = 8, 66.7%) was the most frequent triggering factor. The main clinical symptoms on admission were distal lower limbs' weakness with gait difficulties (83.3%), pain (50%), upper limbs' weakness (50%), and dysphagia for liquids (25%). Peripheral neurophysiological studies revealed acute inflammatory demyelinating polyradiculoneuropathy (AIDP) in 66.6% of the children, acute motor and sensory axonal neuropathy (AMSAN) in 25%, and acute motor axonal neuropathy (AMAN) in 8.3%. Ten individuals (83.3%) received timely treatment with intravenous immunoglobulins (IVIG), and, out of these ten patients, 58% received concomitant treatment with IV methylprednisolone because of a progressive disease course. Complete remission was observed in the majority of individuals (91.6%) within 6 months of symptom onset. Conclusions: Different subtypes of GBS can affect children; however, the outcome is usually positive. Early treatment appears to be important for a favorable outcome.

Benefits of Early Versus Late Initiation of Intravenous Immunoglobulin in the Treatment of Patients With Anti-3-Hydroxy-3-Methylglutaryl-Coenzyme A Reductase Immune-Mediated Necrotizing Myopathy.

No clinical trials have been conducted to establish optimal and effective treatment in patients with immune-mediated necrotizing myopathy (IMNM), which can have a refractory course with increased morbidity from permanent muscle damage, especially in patients who experience delay in diagnosis and treatment. A subset of autoimmune necrotizing myopathy is associated with antibodies against 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR). Treatment involves withdrawing statins and using a combination of immunosuppressant and immunomodulatory treatment. Our study aims to provide longitudinally collected data on outcomes of early versus late initiation of intravenous Ig (IVIG) using our myositis center cohort of patients with anti-HMGCR IMNM. We conducted a retrospective chart review of 31 adult patients of the Oregon Health and Science University Myositis Center who were diagnosed with anti-HMGCR IMNM from September 2016 through October 2022 and reviewed physical examination, serologic laboratory data, and their treatment including prednisone reception as well as treatment response at 0 (the evaluation immediately before IVIG initiation), 3, 6, and 12 months on treatment. We divided this cohort into those who received IVIG at or before six months after receiving the diagnosis of anti-HMGCR IMNM and refer this as the cohort with nondelayed treatment, and those who received IVIG after six months following their diagnosis, which we referred to as the cohort with delayed treatment. Diagnosis of anti-HMGCR IMNM was defined as per the 2016 European Neuromuscular Centre criteria as having all three of elevated serum creatine kinase (CK), proximal muscle weakness, and anti-HMGCR antibodies. We evaluated the response to treatment by using a limited total improvement score (TIS) as per 2016 American College of Rheumatology/EULAR myositis response criteria. Among the 31 total patients, 19 were included within the cohort with nondelayed treatment, and 12 within the cohort with delayed treatment. The two cohorts had a comparable amount of time between the onset of symptoms and diagnosis; however, the cohort with delayed treatment had a significantly longer time between diagnosis and IVIG treatment (P < 0.001). At disease onset, cohorts had a comparable serum CK (P > 0.999), but patients with delayed treatment had an expected lower serum CK (P = 0.016) at the 0-month time point. At the 0-month time point, nine of the patients with nondelayed treatment (47%) required the use of a walker or wheelchair, whereas eight of the cohort with delayed treatment (66%) did. Patients who received nondelayed treatment demonstrated significant improvement in manual muscle testing 8 at the 12-month intervals (P < 0.001). Average serum CK values of all patients measured at the 3, 6, and 12 months did not significantly differ between the groups with nondelayed and delayed treatment. TIS improved more in the group with nondelayed treatment than in the group with delayed treatment (P = 0.002 at 3 months, P = 0.019 at 6 months, and P = 0.001 at 12 months). Seven patients in the group with delayed treatment had permanent residual muscle weakness requiring walker or wheelchair use at 12 months, whereas none of the patients in the group with nondelayed treatment did. Though our results have limitations, they contribute to a growing body of evidence that suggests that IVIG may prove to be a valuable addition to an early and aggressive induction regimen in patients afflicted by anti-HMGCRIMNM, particularly those with moderate to severe weakness requiring the use of a wheelchair or walking aids. Delay in IVIG treatment may lead to the development of permanent residual weakness and long-term disability.

Genetic Landscape of Amyotrophic Lateral Sclerosis in Czech Patients.

Genetic factors are involved in the pathogenesis of familial and sporadic amyotrophic lateral sclerosis (ALS) and constitute a link to its association with frontotemporal dementia (FTD). Gene-targeted therapies for some forms of ALS (C9orf72, SOD1) have recently gained momentum. Genetic architecture in Czech ALS patients has not been comprehensively assessed so far. We aimed to deliver pilot data on the genetic landscape of ALS in our country. A cohort of patients with ALS (n = 88), recruited from two Czech Neuromuscular Centers, was assessed for hexanucleotide repeat expansion (HRE) in C9orf72 and also for genetic variations in other 36 ALS-linked genes via next-generation sequencing (NGS). Nine patients (10.1%) had a familial ALS. Further, we analyzed two subgroups of sporadic patients - with concomitant FTD (n = 7) and with young-onset of the disease (n = 22). We detected the pathogenic HRE in C9orf72 in 12 patients (13.5%) and three other pathogenic variants in FUS, TARDBP and TBK1, each in one patient. Additional 7 novel and 9 rare known variants with uncertain causal significance have been detected in 15 patients. Three sporadic patients with FTD (42.9%) were harbouring a pathogenic variant (all HRE in C9orf72). Surprisingly, none of the young-onset sporadic patients harboured a pathogenic variant and we detected no pathogenic SOD1 variant in our cohort. Our findings resemble those from other European populations, with the highest prevalence of HRE in the C9orf72 gene. Further, our findings suggest a possibility of a missing genetic variability among young-onset patients.

Clinical, Histopathologic, and Genetic Features of Patients With Myofibrillary and Distal Myopathies: Experience From the Italian Network.

The diagnostic process for myofibrillar myopathies (MFM) and distal myopathies (DM) is particularly complex because of the large number of causative genes, the existence of still molecularly undefined disease entities, and the overlapping features between the 2 categories. This study aimed to characterize a large cohort of patients affected by MFM and DM and identify the most important diagnostic and prognostic aspects of these diseases. Patients with either a myopathological diagnosis of MFM or a clinical diagnosis of DM were included in this retrospective multicentric national study. Demographic, genetic, clinical, and histopathologic data of anonymized patients were collected from the neuromuscular centers of the Italian Association of Myology network. Data regarding 132 patients with MFM (mean age 57.0 ± 15.8 years, 49% female) and 298 patients with DM (mean age 50.7 ± 15.9 years, 40% female) were gathered from 20 neuromuscular centers. 69 patients fulfilled the criteria for both groups (distal myopathies with myofibrillar pathology, DM-MP). Molecular confirmation was achieved in 63% of the patients. Fifty-two percent of the patients with MFM carried pathogenic variants in either DES (n = 30), MYOT (n = 20), or DNAJB6 (n = 18), which were also the most frequent disease-causing genes in DM-MP, while GNE (n = 44) and MYH7 (n = 23) were the genes most commonly carrying pathogenic variants in DM. The mean age at onset varied from <25 years in patients with causative variants in MYH7 and DYSF to 59 years in patients with myotilinopathies. Cardiac involvement was reported in 29% of patients with MFM and 16% of patients with DM, with DES and MYH7 variants significantly associated with the development of cardiomyopathy. Respiratory impairment was more prevalent in patients with TTN and DES variants and rare in other disorders such as GNE myopathy and dysferlinopathies, which were instead associated, together with DNAJB6-related and PLIN4-related myopathies, with the risk of losing ambulation during the disease course. The Italian cohort of patients with MFM and DM recapitulates the phenotypic heterogeneity and the partial overlap between the 2 groups. However, in relative contrast to the encountered phenotypic variability, only 5 genes accounted for most of the molecular diagnoses. Specific genetic entities are associated with significantly increased risk of developing cardiorespiratory complications or loss of ambulation, which has relevant prognostic implications.

Pharmacotherapy review and clinical, sub-clinical characteristics in limb-girdle muscular dystrophy

Aims: Review pharmacotherapy in limb-girdle muscular dystrophy and describe clinical, and subclinical characteristics in patients of limb-girdle muscular dystrophy (LGMD). Methods: A meta-analysis with data in PubMed, up to May 2023 on the pharmacotherapy of LGMD combined with a cross-sectional study. Patients were diagnosed with LGMD according to the European Neuromuscular Centre (ENMC) in 1995 at E and Bach Mai Hospitals, from December 2022 to May 2023. Results: 21 studies in pharmacotherapy were conducted, and treatment therapies (glucocorticoid, biological antibody, gene therapy) initially showed safety and some effectiveness in muscular strength. There are some potential gene therapies. The clinical characteristic of collected 15 patients with LGMD was high onset age (20.7±12.5 years), and prolonged diagnosis time (6.3±5.5 years). Most patients showed signs of muscle weakness and muscle atrophy (100 and 86.7%), waddling gait, and Gower’s sign (93.3%). 100% of patients had increased creatine kinase (CK) of 1648.5±2235.8 U/l. Most patients had normal inflammatory indexes. On muscular histopathology, the majority of patients had muscle fiber degeneration, hypertrophy, fibrous tissue invasion, and fat infiltration (86.7%). Conclusions: Treatment therapies in LGMD initially showed safety and some effectiveness in muscular strength; the gene therapies are promising. Clinically, all patients showed signs of muscle weakness in the limb-girdle, most of them showed muscle atrophy, waddling gait, Gowers’ sign, increased CK, negative inflammatory markers, and muscle fiber degeneration on histopathology.

Distinct phenotype and prognosis of immune-mediated necrotizing myopathy based on clinical-serological-pathological classification.

The aim of the study was to investigate the characteristics and prognosis of patients with immune-mediated necrotizing myopathy (IMNM) based on clinical, serological and pathological classification. A total of 138 patients with IMNM who met the 2018 European Neuromuscular Center criteria for IMNM including 62 anti-SRP, 32 anti-HMGCR-positive and 44 myositis specific antibody-negative were involved in the study. All patients were followed up and evaluated remission and relapse. Clustering analysis based on clinical, serological, and pathological parameters was used to define subgroups. Clustering analysis classified IMNM into three clusters. Cluster 1 patients (n = 35) had the highest CK levels, the shortest disease course, severe muscle weakness, and more inflammation infiltration in muscle biopsy. Cluster 2 patients (n = 79) had the lowest CK level and moderate inflammation infiltrate. Cluster 3 patients (n = 24) had the youngest age of onset, the longest disease course and the least frequency of inflammatory infiltration. Patients in cluster 3 had the longest time-to-remission (median survival time: 61[18.3, 103.7] vs 20.5[16.2, 24.9] and 27[19.6, 34.3] months) and shortest relapse-free time than those in cluster 1 and 2 (median remission time 95%CI: 34[19.9, 48.0] vs 73[49.0, 68.7] and 73[48.4, 97.6] months). Patients with age of onset >55 years, more regeneration of muscle fibers, more CD4+T infiltration, and MAC deposition had more favorable outcomes regarding time to achieving remission. Stratification combining clinical, serological, and pathological features could distinguish phenotypes and prognosis of IMNM. The pathological characteristics may impact the long-term prognosis of patients with IMNM.