Explore the vast range of titles available.

Introduction Fatty‐acid oxidation disorders (FAODs) are recessive genetic diseases. Materials and methods We report here clinical and paraclinical data from a retrospective study of 44 adults with muscular FAODs from six French reference centers for neuromuscular or metabolic diseases. Results The study cohort consisted of 44 adult patients: 14 with carnitine palmitoyl transferase 2 deficiency (32%), nine with multiple acyl‐CoA deficiency (20%), 13 with very long‐chain acyl‐CoA dehydrogenase deficiency (30%), three with long‐chain 3‐hydroxyacyl‐CoA dehydrogenase deficiency (7%), and five with short‐chain acyl‐CoA dehydrogenase deficiency (11%). Disease onset occurred during childhood in the majority of patients (59%), with a mean age at onset of 15 years (range = 0.5–35) and a mean of 12.6 years (range = 0–58) from disease onset to diagnosis. The principal symptoms were acute muscle manifestations (rhabdomyolysis, exercise intolerance, myalgia), sometimes associated with permanent muscle weakness. Episodes of rhabdomyolysis were frequent (84%), with a mean creatinine kinase level of 68,958 U/L (range = 660–300,000). General metabolic complications were observed in 58% of patients, respiratory manifestations in 18% of cases, and cardiological manifestations in 9% of cases. Fasting acylcarnitine profile was used to orient genetic explorations in 65% of cases. After a mean follow‐up of 10 years, 33% of patients were asymptomatic and 56% continued to display symptoms after exercise. The frequency of rhabdomyolysis decreased after diagnosis in 64% of cases. Conclusion A standardized register would complete this cohort description of muscular forms of FAODs with exhaustive data, making it possible to assess the efficacy of therapeutic protocols in real‐life conditions and during the long‐term follow‐up of patients.

Myotonic Dystrophy type 1 (DM1) is one of the most heterogeneous hereditary disease in terms of age of onset, clinical manifestations, and severity, challenging both medical management and clinical trials. The CTG expansion size is the main factor determining the age of onset although no factor can finely predict phenotype and prognosis. Differences between males and females have not been specifically reported. Our aim is to study gender impact on DM1 phenotype and severity. We first performed cross-sectional analysis of main multiorgan clinical parameters in 1409 adult DM1 patients (>18 y) from the DM-Scope nationwide registry and observed different patterns in males and females. Then, we assessed gender impact on social and economic domains using the AFM-Téléthon DM1 survey (n = 970), and morbidity and mortality using the French National Health Service Database (n = 3301). Men more frequently had (1) severe muscular disability with marked myotonia, muscle weakness, cardiac, and respiratory involvement; (2) developmental abnormalities with facial dysmorphism and cognitive impairment inferred from low educational levels and work in specialized environments; and (3) lonely life. Alternatively, women more frequently had cataracts, dysphagia, digestive tract dysfunction, incontinence, thyroid disorder and obesity. Most differences were out of proportion to those observed in the general population. Compared to women, males were more affected in their social and economic life. In addition, they were more frequently hospitalized for cardiac problems, and had a higher mortality rate. Gender is a previously unrecognized factor influencing DM1 clinical profile and severity of the disease, with worse socio-economic consequences of the disease and higher morbidity and mortality in males. Gender should be considered in the design of both stratified medical management and clinical trials.

Background and Objectives Mortality in Late‐Onset Pompe Disease (LOPD) has been associated with the rapid progression of respiratory and motor impairment. However, an in‐depth approach to the exact causes of death in these patients is still lacking. Methods In this retrospective cohort study, we analyzed the cause of death and the comorbidities of all deceased patients from the French Late‐Onset Pompe Disease registry. Results By the time of the last extraction, 60 patients diagnosed with LOPD and monitored were registered as deceased in the French national registry, out of a total of 260 patients included. The median age of death was 70.5 years, while the median age of diagnosis was 58 years. The causes of death were divided into disease‐related, accounting for 46.6% of deaths, and non‐disease‐related, comprising 28.3% of total deaths. Fifteen patients (25%) died of an unknown cause. The most frequent etiology of disease‐related death was respiratory failure (n = 14), while for the non‐disease‐related group, malignant neoplasm was the most common (n = 8). Patients in the non‐disease‐related death group had significantly higher forced vital capacity (FVC) values compared to those in the disease‐related death group (54.7% vs. 38%). Treatment‐wise, the median period elapsed from diagnosis to ERT introduction was higher in the disease‐related group. Discussion This is the first study to focus on the specific causes of death of LOPD patients. The majority of the LOPD deaths in the French registry were attributed to respiratory failure and malignant neoplasms.

Background Diagnostic wandering and impasse are major challenges for rare disease management. This study describes the characteristics of patients with rare neuromuscular diseases (RNMDs) without a diagnosis being managed by the French national network for RNMDs (FILNEMUS). Methods Data for RNMD patients managed by FILNEMUS centers between January 2017 and November 2022 were extracted from the French National Rare Disease Database (BNDMR). A network‐wide, standardized, and quality‐controlled process was established to collect additional data for patients without a diagnosis. The demographic and socioeconomic characteristics of these patients were then compared with patients with a confirmed diagnosis. Results 13.5% of patients evaluated (n = 5696/42,256) had no confirmed diagnosis. Comparison with 25,682 managed in the same centers and during the same periods with a confirmed diagnosis revealed that socioeconomic characteristics and region of residence did not influence diagnostic status. However, lack of a confirmed diagnosis was more common in patients aged > 50 years, and older patients had longer periods between first symptom onset and first interaction with an expert center. Evaluation of medical records identified eight RNMDs associated with increased risk of diagnostic wandering and impasse. Conclusions The FILNEMUS national network of expert centers has enabled equality of care for RNMD patients across France, but further measures are needed to promote more rapid referral to these centers, reduce times to first consultation, and maintain patient engagement in the diagnostic process, particularly for later‐onset RNMDs. Between 2017 and 2022, 13.5% of the 42,256 FILNEMUS patients (n = 5696) still lacked a confirmed diagnosis. Socio‐economic status and postcode are off the hook, but crossing the 50‐year mark sharply lengthens the gap between first symptoms and expert evaluation. Eight neuromuscular diseases top the “whodunnit” list, highlighting the need for nimbler diagnostic pathways especially for the silver‐haired sleuths among us.

ObjectiveCerebellar ataxia with neuropathy and vestibular areflexia syndrome (CANVAS) is a recessively inherited multisystem ataxia compromising cerebellar, vestibular, and sensory nerves, which has been associated to a pathogenic AAGGG(n) biallelic expansion repeat in the RFC1 gene. Our objective was to assess its prevalence in a French cohort of patients with idiopathic sporadic late-onset ataxia (ILOA), idiopathic early-onset ataxia (IEOA), or Multiple System Atrophy of Cerebellar type (MSA-C).Methods163 patients were recruited in 3 French tertiary centers: 100 ILOA, 21 IEOA, and 42 patients with possible or probable MSA-C.ResultsA pathogenic biallelic RFC1 AAGGG(n) repeat expansion was found in 15 patients: 15/100 in the ILOA group, but none in the IEOA and MSA-C subgroups. 14/15 patients had a CANVAS phenotype. Only 1/15 had isolated cerebellar ataxia, but also shorter biallelic expansions. Two RFC1 AAGGG(n) alleles were found in 78% of patients with a CANVAS phenotype. In one post-mortem case, the pathophysiological involvement of cerebellum and medullar posterior columns was found.ConclusionOur study confirms the genetic heterogeneity of the CANVAS and that RFC1 repeat expansions should be searched for preferentially in case of unexplained ILOA associated with a sensory neuronopathy, but not particularly in patients classified as MSA-C.

The m.8344A>G mutation in the MTTK gene, which encodes the mitochondrial transfer RNA for lysine, is traditionally associated with myoclonic epilepsy and ragged-red fibres (MERRF), a multisystemic mitochondrial disease that is characterised by myoclonus, seizures, cerebellar ataxia, and mitochondrial myopathy with ragged-red fibres. We studied the clinical and paraclinical phenotype of 34 patients with the m.8344A>G mutation, mainly derived from the nationwide mitoREGISTER, the multicentric registry of the German network for mitochondrial disorders (mitoNET). Mean age at symptom onset was 24.5 years ±10.9 (6–48 years) with adult onset in 75 % of the patients. In our cohort, the canonical features seizures, myoclonus, cerebellar ataxia and ragged-red fibres that are traditionally associated with MERRF, occurred in only 61, 59, 70, and 63 % of the patients, respectively. In contrast, other features such as hearing impairment were even more frequently present (72 %). Other common features in our cohort were migraine (52 %), psychiatric disorders (54 %), respiratory dysfunction (45 %), gastrointestinal symptoms (38 %), dysarthria (36 %), and dysphagia (35 %). Brain MRI revealed cerebral and/or cerebellar atrophy in 43 % of our patients. There was no correlation between the heteroplasmy level in blood and age at onset or clinical phenotype. Our findings further broaden the clinical spectrum of the m.8344A>G mutation, document the large clinical variability between carriers of the same mutation, even within families and indicate an overlap of the phenotype with other mitochondrial DNA-associated syndromes.

Background Sporadic late-onset nemaline myopathy (SLONM) is a rare, late-onset muscle disorder, characterized by the presence of nemaline rods in muscle fibers. Phenotypic characterization in a large cohort and a comprehensive overview of SLONM are lacking. Methods We studied the clinico-pathological features, treatment and outcome in a large cohort of 76 patients with SLONM, comprising 10 new patients and 66 cases derived from a literature meta-analysis (PubMed, 1966–2016), and compared these with 15 reported HIV-associated nemaline myopathy (HIV-NM) cases. In 6 SLONM patients, we performed a targeted next-generation sequencing (NGS) panel comprising 283 myopathy genes. Results SLONM patients had a mean age at onset of 52 years. The predominant phenotype consisted of weakness and atrophy of proximal upper limbs in 84%, of proximal lower limbs in 80% and both in 67%. Other common symptoms included axial weakness in 68%, as well as dyspnea in 55% and dysphagia in 47% of the patients. In 53% a monoclonal gammopathy of unknown significance (MGUS) was detected in serum. The mean percentage of muscle fibers containing rods was 28% (range 1–63%). In 2 cases ultrastructural analysis was necessary to detect the rods. The most successful treatment in SLONM patients (all with MGUS) was autologous peripheral blood stem cell therapy. A targeted NGS gene panel in 6 SLONM patients (without MGUS) did not reveal causative pathogenic variants. In a comparison of SLONM patients with and without MGUS, the former comprised significantly more males, had more rapid disease progression, and more vacuolar changes in muscle fibers. Interestingly, the muscle biopsy of 2 SLONM patients with MGUS revealed intranuclear rods, whereas this feature was not seen in any of the biopsies from patients without paraproteinemia. Compared to the overall SLONM cohort, significantly more HIV-NM patients were male, with a lower age at onset (mean 34 years). In addition, immunosuppression was more frequently applied with more favorable outcome, and muscle biopsies revealed a significantly higher degree of inflammation and necrosis in this cohort. Similar to SLONM, MGUS was present in half of the HIV-NM patients. Conclusions SLONM presents a challenging, but important differential diagnosis to other neuromuscular diseases of adult onset. Investigations for MGUS and HIV should be performed, as they require distinct but often effective therapeutic approaches. Even though SLONM and HIV-NM show some differences, there exists a large clinico-pathological overlap between the 2 entities.

Background The diagnosis of patients with mutations in the VCP gene can be complicated due to their broad phenotypic spectrum including myopathy, motor neuron disease and peripheral neuropathy. Muscle MRI guides the diagnosis in neuromuscular diseases (NMDs); however, comprehensive muscle MRI features for VCP patients have not been reported so far. Methods We collected muscle MRIs of 80 of the 255 patients who participated in the “VCP International Study” and reviewed the T1-weighted (T1w) and short tau inversion recovery (STIR) sequences. We identified a series of potential diagnostic MRI based characteristics useful for the diagnosis of VCP disease and validated them in 1089 MRIs from patients with other genetically confirmed NMDs. Results Fat replacement of at least one muscle was identified in all symptomatic patients. The most common finding was the existence of patchy areas of fat replacement. Although there was a wide variability of muscles affected, we observed a common pattern characterized by the involvement of periscapular, paraspinal, gluteal and quadriceps muscles. STIR signal was enhanced in 67% of the patients, either in the muscle itself or in the surrounding fascia. We identified 10 diagnostic characteristics based on the pattern identified that allowed us to distinguish VCP disease from other neuromuscular diseases with high accuracy. Conclusions Patients with mutations in the VCP gene had common features on muscle MRI that are helpful for diagnosis purposes, including the presence of patchy fat replacement and a prominent involvement of the periscapular, paraspinal, abdominal and thigh muscles.

Background Spinal muscular atrophy (SMA) patients benefit from pre-mRNA splicing modifiers targeting the SMN2 gene, which aims to increase functional SMN production. The animal toxicity affecting spermatogenesis associated with one such treatment raised questions about male SMA patients’ spermatogenesis. Methods This descriptive, cross-sectional study was conducted from June 2022 to July 2023. The study involved adult male patients with genetically confirmed SMA type 2 (SMA2) or SMA3 from 13 French neuromuscular centers. The patients’ general data, motor severity, urological history, exposure to certain factors, parenthood, and spermogram results were obtained. All patients were enrolled prior to exposure to risdiplam. Findings Sixty-eight patients were enrolled ( 36 SMA2 and 32 SMA3 patients). Forty-one patients had fertility data (parenthood history and spermogram analyses) and underwent 33 spermograms. Fertility disorders were identified in 27 of the 41 patients (65·9%, 95%CI 51·3–80·4%) in particular SMA2 patients: 19 cases (90 . 5%, CI 77·9–100%) (SMA3: 8 cases (40%, CI 18·5–61·5%). Among the patients with available spermograms, 81% (27/33) had abnormal sperm concentration; 30% presented azoospermia. These abnormalities were significantly associated with SMA type (more prevalent in SMA2 patients, p  < 0·001), disease motor severity, which included age at the loss of walking ability and wheelchair use duration ( p  < 0·001). The Motor Function Measure (MFM) determined that the sperm counts were also correlated with disease severity ( p  < 0·01). Interpretation The fertility disorders were correlated with SMA severity and were particularly evident in SMA2 patients. In the latter, sperm concentration positively correlated with MFM. This study is the first one to link fertility disorders with spermogram abnormalities in SMA males. Understanding spermatogenesis in SMA is crucial, especially with new therapies such as risdiplam. Consequently, conducting systematic spermogram studies prior to SMA treatment is recommended.

Background Due to their health condition, patients with neuromuscular diseases (NMD) are at greater risk of developing serious complications with COVID-19. The objective of this study was to analyze the prevalence of COVID-19 among NMD patients and the risk factors for its impact and severity during the first wave of the pandemic. Clinical data were collected from NMD-COVID-19 patients, between March 25, 2020 and May 11, 2020 in an anonymous survey carried out by expert physicians from the French Health Care Network Filnemus. Results Physicians reported 84 patients, including: 34 with myasthenia gravis, 27 with myopathy and 23 with neuropathy. COVID-19 had no effect on NMD for 48 (58%) patients and 48 (58%) patients developed low COVID-19 severity. COVID-19 caused the death of 9 (11%) NMD patients. Diabetic patients were at greater risk of dying. Patients with diabetes, hypertension or severe forms of NMD had a higher risk of developing a moderate or severe form of COVID-19. In our cohort, corticosteroids and other immunosuppressants were not significantly associated with higher COVID-19 severity for acquired NMD. Conclusion During this period, a small percentage of French NMD patients was affected by COVID-19 compared to the general French population and COVID-19 had a limited short-term effect on them. Diabetes, hypertension and a severe degree of NMD were identified as risk factors of unfavorable outcome following COVID-19. Conversely, in our cohort of patients with acquired NMD, corticosteroids or other immunosuppressants did not appear to be risk factors for more severe COVID-19.