Spectrum of sleep-disordered breathing and quality of sleep in adolescent and adult patients with spinal muscular atrophy.

Sleep-disordered breathing is common among children with spinal muscular atrophy, but has been hardly studied among adult subjects. Little is known about sleep quality in spinal muscular atrophy. The aims of this study were to evaluate occurrence and characteristics of sleep-disordered breathing and subjective sleep quality among adolescent and adult patients with spinal muscular atrophy type 2 or 3. Twenty patients aged 33.9 ± 15.2 years were studied. They underwent nocturnal cardiorespiratory monitoring, lung and muscular function evaluation, and were administered the Pittsburgh Sleep Quality Index questionnaire. Nineteen patients showed sleep-disordered breathing, with obstructive events in seven subjects and non-obstructive events in the remaining 12. In the latter group, 10 patients showed pseudo-obstructive hypopneas. Patients with non-obstructive sleep-disordered breathing were younger (p = 0.042), had a lower body mass index (p = 0.0001), were more often affected by spinal muscular atrophy type 2 (p = 0.001), and showed worse impairment of respiratory function than patients with obstructive sleep-disordered breathing. Ten patients were classified as poor sleepers and 10 patients good sleepers. In the whole sample, sniff nasal inspiratory pressure proved to be the only independent predictor of sleep quality (p = 0.009). In conclusion, sleep-disordered breathing is common even among adult patients with spinal muscular atrophy type 2 and 3, and may show either obstructive or different types on non-obstructive features. A worse respiratory muscle function is associated to non-obstructive sleep-disordered breathing and poorer sleep quality. Sleep quality should receive greater attention especially in patients with spinal muscular atrophy type 2, who have a poorer respiratory muscle function, as it could affect their quality of life.

Genetic screening for hereditary transthyretin amyloidosis with polyneuropathy in western Sicily: Two years of experience in a neurological clinic.

BACKGROUND AND PURPOSE: Hereditary transthyretin amyloidosis with polyneuropathy (ATTRv-PN) is caused by mutations in the TTR gene, leading to misfolded monomers that aggregate generating amyloid fibrils. METHODS: A prospective systematic genetic screening for ATTRv-PN was proposed in patients presenting with a sensory-motor idiopathic polyneuropathy and two or more "red flags" among the following: family history of polyneuropathy or cardiopathy, bilateral carpal tunnel syndrome, cardiac insufficiency, renal amyloidosis, lumbar tract stenosis, autonomic dysfunction, idiopathic gastrointestinal disease, amyloid deposits on biopsy, and vitreous opacities. The detection rate was calculated, and nonparametric analyses were carried out to underline differences among screened positive versus negative patients. RESULTS: In the first step, 145 suspected patients underwent genetic testing, revealing a diagnosis of ATTRv-PN in 14 patients (10%). Then, cascade screening allowed early recognition of 33 additional individuals (seven symptomatic ATTRv-PN patients and 26 presymptomatic carriers) among 84 first-degree relatives. Patients with a positive genetic test presented a higher frequency of unexplained weight loss, gastrointestinal symptoms, and family history of cardiopathy. CONCLUSIONS: A systematic screening for ATTRv-PN yielded an increased recognition of the disease in our neurological clinic. Unexplained weight loss associated with axonal polyneuropathy had the highest predictive value in the guidance of clinical suspicion. A focused approach for the screening of ATTRv-PN could lead to an earlier diagnosis and identification of asymptomatic carriers, who will be promptly treated after a strict follow-up at the clinical onset.

Comorbidity in myasthenia gravis: multicentric, hospital-based, and controlled study of 178 Italian patients.

BACKGROUND: Myasthenia gravis (MG) is an autoimmune disorder with fluctuating weakness that causes significant disability and morbidity. Comorbidities may influence the course of MG, particularly in specific subgroups. The aim of this study is to investigate the frequency of comorbidities in MG patients compared to healthy controls (HC) and to evaluate their distribution according to age at disease onset, sex, and disease severity. METHODS: MG patients attending the University Hospital "Paolo Giaccone" in Palermo and "SS Annunziata" Hospital in Chieti were enrolled; HC were enrolled from the general population. Non-parametric statistics and logistic regression were used to assess the association of specific comorbidities according to age at disease onset, sex, disease subtypes, and severity of the disease. RESULTS: A total of 356 subjects were included in the study: 178 MG patients (46% F; median age 60 years [51-71]) and 178 sex- and age-matched HC (46% F, median age 59 years [50-66]). Overall, 86% of MG patients and 76% of HC suffered from comorbidities, and MG patients had a higher number of comorbidities compared to HC. Patients with late-onset suffered from more comorbidities than those with early-onset MG. Hypertension was more common in male patients with MG, while thymic hyperplasia, osteoporosis, and autoimmune diseases were more common in females. Respiratory disorders and thymoma were more common in patients with more severe disease (p < 0.05 for all comparisons). CONCLUSION: MG patients, particularly those with late onset, showed a higher prevalence of comorbidities than HC. Assessment of comorbidities in MG is an essential issue to identify the appropriate treatment and achieve the best management.

Cognitive dysfunction in amyotrophic lateral sclerosis: can we predict it?

BACKGROUND AND AIM: Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder characterized by the degeneration of both upper and lower motoneurons in the brain and spinal cord leading to motor and extra-motor symptoms. Although traditionally considered a pure motor disease, recent evidences suggest that ALS is a multisystem disorder. Neuropsychological alterations, in fact, are observed in more than 50% of patients: while executive dysfunctions have been firstly identified, alterations in verbal fluency, behavior, and pragmatic and social cognition have also been described. Detecting and monitoring ALS cognitive and behavioral impairment even at early disease stages is likely to have staging and prognostic implications, and it may impact the enrollment in future clinical trials. During the last 10 years, humoral, radiological, neurophysiological, and genetic biomarkers have been reported in ALS, and some of them seem to potentially correlate to cognitive and behavioral impairment of patients. In this review, we sought to give an up-to-date state of the art of neuropsychological alterations in ALS: we will describe tests used to detect cognitive and behavioral impairment, and we will focus on promising non-invasive biomarkers to detect pre-clinical cognitive decline. CONCLUSIONS: To date, the research on humoral, radiological, neurophysiological, and genetic correlates of neuropsychological alterations is at the early stage, and no conclusive longitudinal data have been published. Further and longitudinal studies on easily accessible and quantifiable biomarkers are needed to clarify the time course and the evolution of cognitive and behavioral impairments of ALS patients.

Rituximab in AChR subtype of myasthenia gravis: systematic review.

Myasthenia gravis (MG) is a chronic autoimmune disorder of the neuromuscular junction characterised by an autoantibody against acetylcholine receptor (AChR-Ab), autoantibody against muscle-specific kinase (MuSK-Ab), lipoprotein-related protein 4 or agrin in the postsynaptic membrane at the neuromuscular junction. Many patients are resistant to conventional treatment and effective therapies are needed. Rituximab (RTX) is a monoclonal antibody directed against CD20 antigen on B cells which has been successfully employed in anti-MuSK-Ab+MG, but the efficacy in anti-AChR-Ab+MG is still debated. The purpose of this systematic review was to describe the best evidence for RTX in the acetylcholine receptor subtype. The authors undertook a literature search during the period of 1999-2019 according to the Preferred Reporting Items for Systematic Reviews and Meta-Analys methodology, employing (myasthenia)+(gravis)+(RTX) as search terms. The analysis was confined to studies that include at least five patients with confirmed anti-AChR-Ab+MG. Thirteen studies have been selected, showing a good safety. The data obtained were heterogeneous in terms of posology, administration scheme and patients' evaluation, ranging from a minimum of two to a maximum of three cycles. RTX led to a sustained clinical improvement with prolonged time to relapse, in parallel to a reduction or discontinuation of other immunosuppressive therapies. Treatment with RTX appears to work in some but not all patients with anti-AChR-Ab+MG, but randomised controlled trials are needed. Future studies should take into account the subtype of MG and employ reliable measures of outcome and severity focusing on how to identify patients who may benefit from the treatment. Trial registration number: NCT02110706.

Efgartigimod beyond myasthenia gravis: the role of FcRn-targeting therapies in stiff-person syndrome.

Stiff-person syndrome (SPS) is a rare autoimmune neurological disorder characterized by high titers of antibodies against glutamic acid decarboxylase (GAD) causing impaired GABAergic inhibitory neurotransmission. To date, there is not a defined therapy for such condition, but immunomodulating therapies, such as plasma exchange, intravenous immunoglobulins, and rituximab, have been widely used in clinical practice. However, the efficacy and tolerability of these treatments is not well established. Efgartigimod, a new neonatal Fc receptor (FcRn) blocker, is a human IgG1 antibody Fc fragment engineered with increased affinity for FcRn binding, leading to a reduction in IgGs levels, including pathogenic IgG autoantibody showing promising results in neurological autoimmune disorders and has been approved for the treatment of AChR-seropositive generalized myasthenia gravis (MG). In this study, we report and describe the first data on treatment with efgartigimod in three patients affected by both AChR-seropositive generalized MG and anti-GAD-seropositive SPS. Patients were followed since the start of efgartigimod and for the whole treatment period (12 weeks). MG symptoms were assessed with the "MG activity of daily living score" and the Quantitative Myasthenia Gravis score, while SPS ones were assessed with the "SPS activity of daily living score"; muscle strength was assessed with the Medical Research Council Sum score; the overall disability from MG and SPS was assessed by the modified Rankin Scale. All patients showed an improvement in symptoms of both SPS and MG after 2 cycles of treatment. Our data suggest that efgartigimod may be considered as a candidate drug for SPS and other autoantibody-mediated neurological disorders.

Aromatic L-Amino Acid Decarboxylase Deficiency: A Genetic Screening in Sicilian Patients with Neurological Disorders.

Aromatic L-amino acid decarboxylase deficiency (AADCd) is a rare autosomal recessive neurometabolic disorder caused by AADC deficiency, an enzyme encoded by the DDC gene. Since the enzyme is involved in the biosynthesis of serotonin and dopamine, its deficiency determines the lack of these neurotransmitters, but also of norepinephrine and epinephrine. Onset is early and the key signs are hypotonia, movement disorders (oculogyric crises, dystonia and hypokinesia), developmental delay and autonomic dysfunction. Taiwan is the site of a potential founder variant (IVS6+4A>T) with a predicted incidence of 1/32,000 births, while only 261 patients with this deficit have been described worldwide. Actually, the number of affected persons could be greater, given that the spectrum of clinical manifestations is broad and still little known. In our study we selected 350 unrelated patients presenting with different neurological disorders including heterogeneous neuromuscular disorders, cognitive deficit, behavioral disorders and autism spectrum disorder, for which the underlying etiology had not yet been identified. Molecular investigation of the DDC gene was carried out with the aim of identifying affected patients and/or carriers. Our study shows a high frequency of carriers (2.57%) in Sicilian subjects with neurological deficits, with a higher concentration in northern and eastern Sicily. Assuming these data as representative of the general Sicilian population, the risk may be comparable to some rare diseases included in the newborn screening programs such as spinal muscular atrophy, cystic fibrosis and phenylketonuria.

The Clinical Relevance of Artificial Intelligence in Migraine.

Migraine is a burdensome neurological disorder that still lacks clear and easily accessible diagnostic biomarkers. Furthermore, a straightforward pathway is hard to find for migraineurs' management, so the search for response predictors has become urgent. Nowadays, artificial intelligence (AI) has pervaded almost every aspect of our lives, and medicine has not been missed. Its applications are nearly limitless, and the ability to use machine learning approaches has given researchers a chance to give huge amounts of data new insights. When it comes to migraine, AI may play a fundamental role, helping clinicians and patients in many ways. For example, AI-based models can increase diagnostic accuracy, especially for non-headache specialists, and may help in correctly classifying the different groups of patients. Moreover, AI models analysing brain imaging studies reveal promising results in identifying disease biomarkers. Regarding migraine management, AI applications showed value in identifying outcome measures, the best treatment choices, and therapy response prediction. In the present review, the authors introduce the various and most recent clinical applications of AI regarding migraine.

Insomnia and Migraine: A Missed Call?

Migraine is one of the most prevalent and disabling neurological conditions, presenting episodes of throbbing headache that limit activities of daily living. Several factors may influence migraine frequency, such as lifestyle or alcohol consumption. Among the most recognised ones, sleep plays a biunivocal role, since poor sleep quality may worsen migraine frequency, and a high migraine frequency may affect sleep quality. In this paper, the authors evaluate the relationship between migraine and insomnia by exploring a cohort of patients affected by episodic or chronic migraine. To do so, a phone interview was performed, asking patients about their migraine frequency and mean pain intensity, in addition to the questions of the Insomnia Severity Index. The last one explores several symptoms impairing sleep that focus on insomnia. Patients complaining of insomnia showed an increased migraine frequency, and a weak but significant correlation was found between headache days per month and insomnia scores. Such results were particularly evident in patients affected by chronic migraine. Such results suggest how insomnia, in the presented data, seems to be associated with migraine frequency but not with pain intensity.

Physical Activity in Patients with Neuromuscular Disease Three Years after COVID-19, a Longitudinal Survey: The After-Effects of the Quarantine and the Benefits of a Return to a Healthier Life-Style.

BACKGROUND: Quarantine was one of the strategies adopted by governments against the spread of COVID-19. This restriction has caused an increase in sedentary behaviors and a decrease in the practice of physical activity (PA), with a consequent negative impact on lifestyle both in healthy people and in those who need constant practice of PA to combat diseases, such as patients suffering from neuromuscular diseases (NMDs). Hence, this study aimed to compare PA levels among patients with NMD during and after quarantine. METHODS: An adapted version of the International Physical Activity Questionnaire Short-Form and the Short-Form Health Survey were administered during COVID-19 quarantine (T0) and after 3 years (T1) to 91 Italian patients with NMDs. RESULTS: We found a significant increase in the total PA level at T1, with no significant changes in vigorous-intensity PA. Moreover, a significant decrease in the PA level was found among the patients with different NMDs. No significant changes in physical component scores and mental component scores were detected. CONCLUSIONS: Our results suggest that it would be necessary to provide alternative indoor exercise settings to prevent the adoption of sedentary behaviors.

Sensory neuropathy in amyotrophic lateral sclerosis: a systematic review.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by the degeneration of both upper and lower motoneurons, leading to motor and non-motor symptoms. Recent evidence suggests that ALS is indeed a multisystem disorder, associated with cognitive impairment, dysautonomia, pain and fatigue, excess of secretions, and sensory symptoms. To evaluate whether sensory neuropathy could broaden its spectrum, we systematically reviewed its presence and characteristics in ALS, extracting data on epidemiological, clinical, neurophysiological, neuropathological, and genetic features. Sensory neuropathy can be found in up to 20% of ALS patients, affecting both large and small fibers, although there is a great heterogeneity related to different techniques used for its detection (electromyography vs skin biopsy vs nerve biopsy). Moreover, the association between CIDP-like neuropathy and ALS needs to be better explored, although it could be interpreted as part of the neuroinflammatory process in the latter disease. Sensory neuropathy in ALS may be associated with a spinal onset and might be more frequent in SOD1 patients. Moreover, it seems mutually exclusive with cognitive impairment. No associations with sex and other genetic mutation were observed. All these data in the literature reveal the importance of actively looking for sensory neuropathy in ALS patients, and suggest including sensory neuropathy among ALS non-motor features, as it may explain sensory symptoms frequently reported throughout the course of the disease. Its early identification could help avoid diagnostic delays and improve patients' treatment and quality of life.

Frequency and Correlates of Mild Cognitive Impairment in Myasthenia Gravis.

BACKGROUND: Antibodies against acetylcholine receptors (AChRs) can also target nicotinic AChRs that are present throughout the central nervous system, thus leading to cognitive dysfunctions in patients with myasthenia gravis (MG). However, the presence of cognitive impairment in MG is controversial, and the factors that may influence this risk are almost completely unknown. In this study, the frequency of mild cognitive impairment (MCI) in MG, as well as the clinical, immunological, and behavioral correlates of MCI in MG were evaluated. METHODS: A total of 52 patients with MG underwent a comprehensive assessment including motor and functional scales, serological testing, and neuropsychological and behavioral evaluation. RESULTS: The frequency of MCI was 53.8%, and the most impaired cognitive domains were, in order, visuoconstructive/visuospatial skills, memory, and attention. After multivariate analysis, only pyridostigmine use was inversely associated with the presence of MCI, while a trend toward a positive association between MCI and disease severity and arms/legs hyposthenia was found. Correlation analyses showed that daily doses of prednisone and azathioprine significantly correlated with depressive symptomatology, while disease severity significantly correlated with depressive symptomatology and sleep disturbance. CONCLUSIONS: The presence of MCI is rather frequent in MG and is characterized by multidomain amnestic impairment. Such preliminary data need further confirmation on larger case series.

Usefulness and Clinical Impact of Whole-Body MRI in Detecting Autoimmune Neuromuscular Disorders.

Autoimmune neuromuscular diseases are a group of heterogenous pathologies secondary to the activation of the immune system that damage the structures of the peripheric nerve, the neuromuscular junction, or the skeleton muscle. The diagnosis of autoimmune neuromuscular disorders comprises a combination of data from clinical, laboratory, electromyography, imaging exam, and biopsy. Particularly, the whole-body MRI examination in the last two decades has been of great use in the assessment of neuromuscular disorders. MRI provides information about the structures involved and the status of activity of the disease. It can also be used as a biomarker, detect the pattern of specific muscle involvement, and is a useful tool for targeting the optimal muscle site for biopsy. In this work, we summarized the most used technical protocol of whole-body MRI and the role of this imaging technique in autoimmune neuromuscular disorders.

Diagnosis and Management of Seronegative Myasthenia Gravis: Lights and Shadows.

Myasthenia gravis (MG) is an antibody-mediated neuromuscular disease affecting the neuromuscular junction. In most cases, autoantibodies can be detected in the sera of MG patients, thus aiding in diagnosis and allowing for early screening. However, there is a small proportion of patients who have no detectable auto-antibodies, a condition termed "seronegative MG" (SnMG). Several factors contribute to this, including laboratory test inaccuracies, decreased antibody production, immunosuppressive therapy, immunodeficiencies, antigen depletion, and immune-senescence. The diagnosis of SnMG is more challenging and is based on clinical features and neurophysiological tests. The early identification of these patients is needed in order to ensure early treatment and prevent complications. This narrative review aims to examine the latest updates on SnMG, defining the clinical characteristics of affected patients, diagnostic methods, management, and therapeutic scenarios.

The Mitochondrial tRNASer(UCN) Gene: A Novel m.7484A>G Mutation Associated with Mitochondrial Encephalomyopathy and Literature Review.

Mitochondrial tRNASer(UCN) is considered a hot-spot for non-syndromic and aminoglycoside-induced hearing loss. However, many patients have been described with more extensive neurological diseases, mainly including epilepsy, myoclonus, ataxia, and myopathy. We describe a novel homoplasmic m.7484A>G mutation in the tRNASer(UCN) gene affecting the third base of the anticodon triplet in a girl with profound intellectual disability, spastic tetraplegia, sensorineural hearing loss, a clinical history of epilepsia partialis continua and vomiting, typical of MELAS syndrome, leading to a myoclonic epilepticus status, and myopathy with severe COX deficiency at muscle biopsy. The mutation was also found in the homoplasmic condition in the mother who presented with mild cognitive deficit, cerebellar ataxia, myoclonic epilepsy, sensorineural hearing loss and myopathy with COX deficient ragged-red fibers consistent with MERRF syndrome. This is the first anticodon mutation in the tRNASer(UCN) and the second homoplasmic mutation in the anticodon triplet reported to date.

Immunological Aspects of Von Hippel-Lindau Disease: A Focus on Neuro-Oncology and Myasthenia Gravis.

Von Hippel-Lindau (VHL) disease is an autosomal dominant condition that predisposes affected individuals to a variety of malignant and benign neoplasms. The pathogenetic turning point of this illness is the accumulation of hypoxia-inducible factor (HIF)-1α, a transcription factor of several genes involved in oncogenesis, angiogenesis, tissue regeneration, metabolic regulation, hematopoiesis, and inflammatory responses. From an oncological perspective, increased awareness of the molecular pathways underlying this disease is bringing us closer to the development of specific and targeted therapies. Meanwhile, on the surgical side, improved understanding can help to better identify the patients to be treated and the surgical timing. Overall, pathogenesis research is crucial for developing patient-tailored therapies. One of the actual key topics of interest is the link between the VHL/HIF axis and inflammation. The present study aims to outline the fundamental mechanisms that link VHL disease and immune disorders, as well as to explore the details of the overlap between VHL disease and myasthenia gravis (MG) pathogenetic pathways. As a result, MG becomes a paradigm for autoimmune disorders that might be related with VHL disease.

Effects of a Single Session of OnabotulinumtoxinA Therapy on Sleep Quality and Psychological Measures: Preliminary Findings in a Population of Chronic Migraineurs.

Chronic migraine is a burdensome condition, and onabotulinumtoxinA is revealed to be an effective therapy. Migraine shows a bidirectional relationship with sleep, but the effects of preventive therapies on sleep quality are poorly studied. This study aims to evaluate the effects of a single session of onabotulinumtoxinA on patients' sleep quality and correlates the results with measures of comorbid anxiety/depression. Patients completed self-administrable questionnaires about sleep quality (Pittsburgh Sleep Quality Index-PSQI) and psychological symptoms (Beck Depression Inventory, 2nd edition-BDI-II-and Hospital Anxiety and Depression Scale-HADS-subscales "a" and "d" for anxiety and depression, respectively), and reported migraine frequency at baseline and after 12 weeks. The 42 included patients showed a significant reduction in migraine days (from 20.6 ± 6.0 to 13.6 ± 6.2, p < 0.001), while no changes were observed in sleep quality (PSQI score from 11.0 ± 5.0 to 9.8 ± 4.6, p = 0.277) or psychological measures (BDI-II from 16.7 ± 10.2 to 15.7 ± 10.3, p = 0.678; HADS-a from 10.3 ± 4.8 to 9.3 ± 5.5, p = 0.492; and HADS-d from 7.2 ± 3.9 to 7.1 ± 5.0, p = 0.901). On the other hand, a strong correlation among PSQI, BDI-II, HADS-a, and HADS-d scores (p < 0.001, rho > 0.7) was found. Despite its efficacy in migraine prevention, a single session of onabotulinumtoxinA was not able to affect patients' sleep quality or their psychological symptoms.