Cardiovascular autonomic failure in hereditary transthyretin amyloidosis and TTR carriers is an early and progressive disease marker.

BACKGROUND: The cardiomyopathic and neuropathic phenotype of hereditary transthyretin amyloidosis are well recognized. Cardiovascular autonomic dysfunction is less systematically and objectively assessed. METHODS: Autonomic and clinical features, quantitative cardiovascular autonomic function, and potential autonomic prognostic markers of disease progression were recorded in a cohort of individuals with hereditary transthyretin amyloidosis and in asymptomatic carriers of TTR variants at disease onset (T0) and at the time of the first quantitative autonomic assessment (T1). The severity of peripheral neuropathy and its progression was stratified with the polyneuropathy disability score. RESULTS: A total of 124 individuals were included (111 with a confirmed diagnosis of hereditary transthyretin amyloidosis, and 13 asymptomatic carriers of TTR variants). Symptoms of autonomic dysfunction were reported by 27% individuals at T0. Disease duration was 4.5 ± 4.0 years [mean ± standard deviation (SD)] at autonomic testing (T1). Symptoms of autonomic dysfunction were reported by 78% individuals at T1. Cardiovascular autonomic failure was detected by functional testing in 75% individuals and in 64% of TTR carriers. Progression rate from polyneuropathy disability stages I/II to III/IV seemed to be shorter for individuals with autonomic symptoms at onset [2.33 ± 0.56 versus 4.00 ± 0.69 years (mean ± SD)]. CONCLUSIONS: Cardiovascular autonomic dysfunction occurs early and frequently in individuals with hereditary transthyretin amyloidosis within 4.5 years from disease onset. Cardiovascular autonomic failure can be subclinical in individuals and asymptomatic carriers, and only detected with autonomic function testing, which should be considered a potential biomarker for early diagnosis and disease progression.

Paraneoplastic neurological syndromes of the central nervous system: a single institution 7-year case series.

BACKGROUND: Paraneoplastic neurological syndromes (PNSs) are nonmetastatic complications of malignancy, defined by the presence of onconeural antibodies (ONAs). ONAs may be found in 60% of patients with central nervous system (CNS) involvement, and they are directed against intraneuronal antigens or channels, receptors or associated proteins located at the synaptic or extra-synaptic neuronal cell membrane. Given its rare incidence, there are few epidemiological case series on CNS-PNS. We aim to discuss the variability of CNS-PNSs etiology, clinical features, management and outcome, highlighting the importance of early recognition and appropriate treatment, leading to significant reduction of mortality and morbidity. METHODS: We retrospectively reviewed our 7-years single-center experience, and specifically discussed the underlying etiology, parenchymal CNS involvement, and the acute treatment response. Only cases fulfilling PNS Euronetwork criteria for definitive PNS were included. RESULTS: A total of 26 probable PNSs cases involving CNS were identified. We reported medical records of eleven (42.3%) illustrative cases, meeting the criteria of definite PNS and presenting variable clinical spectrum and different radiological appearances. Our series has a relative paucity of the most common syndromes and larger portion of clinical diagnosis with ONAs. Well-characterized ONAs had been detected in CSF of six patients. CONCLUSIONS: Our case series supports the utmost importance of early recognition of CNS-PNSs. Screening for occult malignancies should not be limited to patients with classical CNS syndrome. Empiric immunomodulatory therapy may be considered before the diagnostic evaluation is completed, in order to prevent unfavorable outcome. Late presentations should not discourage initiation of treatment.

Role of Sport Activity on Quality of Life in Charcot-Marie-Tooth 1A Patients.

The present study aims to investigate the benefits induced by physical activity/practiced sport in Charcot-Marie-Tooth 1A (CMT1A). Patients were divided into sport and no-sport groups according to their sports performance habit. Thirty-one patients were enrolled, of which 14 practiced sports and 17 did not. Clinical assessments were administered to evaluate disability, self-esteem, depression, quality of life, and pain. Statistical analysis revealed significant differences in terms of gender in the no-sport group compared to the sport group (p = 0.04). Regarding the quality of life, physical function (p = 0.001), general health (p = 0.03), social function (p = 0.04), and mental health (p = 0.006) showed better patterns in the sport group than no-sport group. Moreover, neuropathic pain was reduced in the sport group according to the Neuropathic Pain Symptom Inventory (p = 0.001) and ID-PAIN (p = 0.03). The other administered questionnaires showed no significant differences. Our study confirms that CMT1A patients, who practice sports, with a similar severity of disability, may have a better physical quality of life while suffering less neuropathic pain than their peers who do not practice sports. Results recommend the prescription of sport in CMT1A patients.

The Spinal Muscular Atrophy Health Index: Italian validation of a disease-specific outcome measure.

Patient report outcome measures in Spinal Muscular Atrophy (SMA) represent a potential complement to observer rated scales which can be used to better understand treatment response. We developed, translated and validated an Italian version of the Spinal Muscular Atrophy Health Index (SMAHI), a disease-specific, patient reported outcome measure questionnaire, designed to estimate the patients' perception of disease burden. Test-retest reliability was assessed in 37 patients (16 children aged 12-17 and 21 adults) and was excellent in both cohorts. Internal consistency in an additional 98 patients (24 children, 74 adults) was also excellent (Cronbach's alpha = 0.93 and 0.91 respectively). In children the highest level of disease burden was generated from lower limb dysfunction and fatigue as well as their perception of decreased performance in social situations. Most patients in the adult cohort were sitters and complained of problems with upper limb functions as well as of fatigue. The SMAHI-IT was also able to differentiate between SMA types according to diseases severity. The results of our study demonstrate that the SMAHI can be considered a marker of disease-specific burden in patients with SMA with a high test-retest reliability and internal validity in Italian patients aged 12 and older.

ATTRv amyloidosis Italian Registry: clinical and epidemiological data.

INTRODUCTION: ATTRv amyloidosis is worldwide spread with endemic foci in Portugal and Sweden, Japan, Brazil, Maiorca, and Cyprus. A national Registry was developed to characterise the epidemiology and genotype-phenotype correlation of ATTRv amyloidosis in Italy and to allow a better planning of diagnostic and therapeutic services. METHODS: Fifteen Italian referral centres for amyloidosis spread all over the country have contributed to the Registry. RESULTS: Four-hundred-forty-seven subjects were enrolled, 187 asymptomatic carriers and 260 affected patients. Thirty-one different mutations were recorded. The seven most represented genetic variants were significantly different in terms of age at onset, clinical features and geographical distribution. National prevalence is 4.33/million with higher values in Southern Italy. Overall symptoms of polyneuropathy were present at disease onset in about half of the patients, symptoms of cardiomyopathy in a quarter of patients, the rest referring carpal tunnel syndrome, dysautonomia or lumbar spinal stenosis. 52.6% of patients were in FAP stage 1, 20.4% in stage 2 and 13.5% in stage 3, while 13.5% patients had no neuropathy, presenting only cardiological symptoms. CONCLUSIONS: We presented an epidemiological study based on collaboration among referral centres for ATTRv amyloidosis spread in all the Italian territory, using web-based Registry. It provided a detailed map of the regional distribution of the disease. The increased awareness of the disease among general practitioners and medical specialists has contributed to reduce the diagnostic delay and the rate of misdiagnosis. The Registry will allow to collect also future information about clinical and instrumental follow-up.

Psychosocial impact of sport activity in neuromuscular disorders.

Previous studies demonstrated the benefits of motor exercise and physical activity in neuromuscular disorders. However, very few papers assessed the effects of sport practise. The aim of this multicentre study was to assess the impact of sport activity on self-esteem and emotional regulation in a cohort of athletes with neuromuscular disorders. The 38 patients with Duchenne, Becker or other types of muscular dystrophy or spinal muscular atrophy practising sport (aged 13-49 years) and 39 age-, gender-, disability- and disease-matched patients not practising sport were enrolled. Testing procedures to assess self-esteem, anxiety and depression disorder, personality trait and quality of life (QoL) were used. Patients practising sport had a significantly higher self-esteem, lower level of depression, greater social own identity and adherence and QoL. Frequency of sport activity may represent a complementary therapy in neuromuscular disorders to improve mental and social well-being.

Antibodies to neurofascin, contactin-1, and contactin-associated protein 1 in CIDP: Clinical relevance of IgG isotype.

OBJECTIVE: To assess the prevalence and isotypes of anti-nodal/paranodal antibodies to nodal/paranodal proteins in a large chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) cohort, compare clinical features in seronegative vs seropositive patients, and gather evidence of their isotype-specific pathogenic role. METHODS: Antibodies to neurofascin-155 (Nfasc155), neurofascin-140/186 (Nfasc140/186), contactin-1 (CNTN1), and contactin-associated protein 1 (Caspr1) were detected with ELISA and/or cell-based assay. Antibody pathogenicity was tested by immunohistochemistry on skin biopsy, intraneural injection, and cell aggregation assay. RESULTS: Of 342 patients with CIDP, 19 (5.5%) had antibodies against Nfasc155 (n = 9), Nfasc140/186 and Nfasc155 (n = 1), CNTN1 (n = 3), and Caspr1 (n = 6). Antibodies were absent from healthy and disease controls, including neuropathies of different causes, and were mostly detected in patients with European Federation of Neurological Societies/Peripheral Nerve Society (EFNS/PNS) definite CIDP (n = 18). Predominant antibody isotypes were immunoglobulin G (IgG)4 (n = 13), IgG3 (n = 2), IgG1 (n = 2), or undetectable (n = 2). IgG4 antibody-associated phenotypes included onset before 30 years, severe neuropathy, subacute onset, tremor, sensory ataxia, and poor response to intravenous immunoglobulin (IVIG). Immunosuppressive treatments, including rituximab, cyclophosphamide, and methotrexate, proved effective if started early in IVIG-resistant IgG4-seropositive cases. Five patients with an IgG1, IgG3, or undetectable isotype showed clinical features indistinguishable from seronegative patients, including good response to IVIG. IgG4 autoantibodies were associated with morphological changes at paranodes in patients' skin biopsies. We also provided preliminary evidence from a single patient about the pathogenicity of anti-Caspr1 IgG4, showing their ability to penetrate paranodal regions and disrupt the integrity of the Nfasc155/CNTN1/Caspr1 complex. CONCLUSIONS: Our findings confirm previous data on the tight clinico-serological correlation between antibodies to nodal/paranodal proteins and CIDP. Despite the low prevalence, testing for their presence and isotype could ultimately be part of the diagnostic workup in suspected inflammatory demyelinating neuropathy to improve diagnostic accuracy and guide treatment. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that antibodies to nodal/paranodal proteins identify patients with CIDP (sensitivity 6%, specificity 100%).

Genetic neuromuscular disorders: living the era of a therapeutic revolution. Part 1: peripheral neuropathies.

Recent advances in pathophysiological and genetic mechanisms of some neuromuscular diseases and a rapid progress in new pharmacological technologies led to an accelerated development of innovative treatments, generating an unexpected therapeutic revolution. In part 1, we report already commercially available drugs, just approved drugs and new therapeutic promises in the treatment of peripheral neuropathies. Hereditary transthyretin amyloidosis (hATTR) is a devastating disease due to amyloid accumulation in peripheral nerves, heart and autonomic system. The first specific drug approved for hATTR was tafamidis, a TTR tetramer stabilizer. In 2018, the positive results of two phase 3 trials have been reported leading to start of regulatory approval route for inotersen, an antisense oligonucleotide and patisiran, the first-ever RNA interference (RNAi) therapeutic. System biology targeting approach has indicated baclofen, naltrexone and sorbitol in combination (PXT3003) as candidate drugs for Charcot-Marie-Tooth disease type 1A. This hypothesis was confirmed in experimental models and in phase 2 and 3 clinical trials. Givosiran, another RNAi therapeutic, targeting 5-aminolevulinic acid synthase, has been positively tested in acute intermittent porphyria in phase 1/2 and ongoing phase 3 trials. Although allogenic hematopoietic stem cell transplantation resulted recently a long-term therapy in mitochondrial neurogastrointestinal encephalomyopathy (MNGIE), a new strategy is liver transplantation which is able to revert the severe biochemical and clinical imbalance of the disease. Recently, a gene therapy has been tested in a MNGIE murine model, indicating that it may become a new therapeutic option.

6MWT performance correlates with peripheral neuropathy but not with cardiac involvement in patients with hereditary transthyretin amyloidosis (hATTR).

Hereditary transthyretin amyloidosis (hATTR) is a life-threatening multisystemic disease with sensory-motor peripheral neuropathy, cardiomyopathy and dysautonomia. Although the six-minute walk test (6MWT) is one of the most popular clinical tests to assess functional exercise capacity in cardiopulmonary and neuromuscular diseases, little is known about 6MWT in evaluating hATTR patients. A prospective single-center pilot study was performed in twenty hATTR patients, comparing 6MWT with widely used outcome measures. After 18 months, fourteen patients were re-evaluated. 6MWT performance was highly related with familial amyloidotic polyneuropathy stage and polyneuropathy disability score, and with CMT examination score, neuropathy impairment score-lower limbs and Kumamoto score. There was no correlation with compound autonomic dysfunction test, modified body mass index and numerous indices of heart dysfunction. After 18 months, familial amyloidotic polyneuropathy stage and polyneuropathy disability score systems were not able to reveal any significant change, whereas all other outcome measures significantly worsened. Among the outcome measures monitoring the neuropathic disturbances, neuropathy impairment score-lower limbs showed the highest responsiveness to change (adjusted effect size: 0.79), followed by CMT examination score (0.67), Kumamoto scale (0.65), 6MWT (0.62). 10MWT showed a very small value (0.21). Compound autonomic dysfunction test had a large value (0.91) whereas modified body mass index a small/moderate value (0.49). 6MWT is a simple and sensitive tool to monitor neuropathic involvement but not cardiac dysfunction in hATTR course.

Non-coding variants contribute to the clinical heterogeneity of TTR amyloidosis.

Coding mutations in TTR gene cause a rare hereditary form of systemic amyloidosis, which has a complex genotype-phenotype correlation. We investigated the role of non-coding variants in regulating TTR gene expression and consequently amyloidosis symptoms. We evaluated the genotype-phenotype correlation considering the clinical information of 129 Italian patients with TTR amyloidosis. Then, we conducted a re-sequencing of TTR gene to investigate how non-coding variants affect TTR expression and, consequently, phenotypic presentation in carriers of amyloidogenic mutations. Polygenic scores for genetically determined TTR expression were constructed using data from our re-sequencing analysis and the GTEx (Genotype-Tissue Expression) project. We confirmed a strong phenotypic heterogeneity across coding mutations causing TTR amyloidosis. Considering the effects of non-coding variants on TTR expression, we identified three patient clusters with specific expression patterns associated with certain phenotypic presentations, including late onset, autonomic neurological involvement, and gastrointestinal symptoms. This study provides novel data regarding the role of non-coding variation and the gene expression profiles in patients affected by TTR amyloidosis, also putting forth an approach that could be used to investigate the mechanisms at the basis of the genotype-phenotype correlation of the disease.

Parenteral nutrition improves nutritional status, autonomic symptoms and quality of life in transthyretin amyloid polyneuropathy.

Transthyretin familial amyloid polyneuropathy (TTR-FAP) is an inherited amyloidosis, leading to death in about ten years in most cases due to cardiac failure or wasting syndrome. Previous studies showed that modified body mass index was related to time before death, duration of gastrointestinal disturbances, malabsorption and functional capacity. We report two patients in whom nutritional status worsened despite diet modification, hypercaloric supplement and two relevant therapeutic approaches such as liver transplant and tafamidis meglumine, respectively. The first patient, a 52-year-old lady carrying Thr49Ala mutation, had a disease duration of twelve years and had lost weight up to 35 kg because of daily diarrhea. The second patient, a 63-year-old man with Glu89Gln mutation and a disease duration of fifteen years, was in the New York Heart Association (NYHA) Functional Classification class III and his weight was 39 kg. In both cases, a peripherally inserted central catheter was placed for parenteral nutrition. It allowed to improve their nutritional status and clinical conditions, with body weight gains of 11 and 8 kg in a one year follow-up, respectively. Moreover, reduction of autonomic symptoms including postural hypotension, nausea and diarrhoea was recorded with ameliorated quality of life. Our experience suggests that parenteral nutrition may be useful in reducing complications and disabilities in TTR-FAP patients, even when all dietary adjustments have been ineffective. Reasonably, the improvement in nutritional status may prolong survival in TTR-FAP patients.

Charcot-Marie-Tooth 2F: phenotypic presentation of the Arg136Leu HSP27 mutation in a multigenerational family.

Mutations in the small heat-shock protein HSP27 gene are associated with distal hereditary motor neuropathy and with the axonal form of Charcot-Marie-Tooth disease type 2. We present the clinical and electrophysiological data on a multigenerational family with the p.Arg136Leu HSP27 mutation. Atypical features such as deafness and pyramidal signs were present in our cases adding new data to the large spectrum of HSP27-related phenotype.

Transthyretin-Related Familial Amyloid Polyneuropathy (TTR-FAP): A Single-Center Experience in Sicily, an Italian Endemic Area.

BACKGROUND: Familial amyloid polyneuropathy related to transthyretin gene (TTR-FAP) is a life-threatening disease transmitted as an autosomal dominant trait. Val30Met mutation accounts for the majority of the patients with large endemic foci especially in Portugal, Sweden and Japan. However, more than one hundred other mutations have been described worldwide. A great phenotypic variability among patients with late- and early-onset has been reported. OBJECTIVE: To present a detailed report of TTR-FAP patients diagnosed in our tertiary neuromuscular center, in a 20-year period. METHODS: Clinical informations were gathered through the database of our center. RESULTS: The study involved 76 individuals carrying a TTR-FAP mutation. Three phenotypes were identified, each corresponding to a different TTR variant, homogeneous within and heterogeneous between each other: i) Glu89Gln mutation, characterised by 5th - 6th decade onset, neuropathy as presenting symptoms, early heart dysfunction, cardiomyopathy as major cause of mortality followed by dysautonomia and cachexia; ii) Phe64Leu mutation, marked by familiarity reported in one-half of cases, late onset, severe peripheral neuropathy, moderate dysautonomia and mild cardiomyopathy, death for wasting syndrome; iii) Thr49Ala mutation, distinguished by onset in the 5th decade, autonomic disturbances as inaugural symptoms which may remain isolated for many years, moderate polyneuropathy, cachexia as major cause of mortality followed by cardiomyopathy. CONCLUSIONS: This survey highlighted a prevalence of 8.8/1,000,000 in Sicily Island. Good knowledge of the natural history of the disease according to different TTR mutations allow clinicians to optimise multiprofessional care for patients and to offer carriers a personalized follow-up to reveal first signs of the disease.

Autonomic involvement in subacute and chronic immune-mediated neuropathies.

Autonomic function can be impaired in many disorders in which sympathetic, parasympathetic, and enteric arms of the autonomic nervous system are affected. Signs and symptoms of autonomic involvement are related to impairment of cardiovascular, gastrointestinal, urogenital, thermoregulatory, sudomotor, and pupillomotor autonomic functions. Availability of noninvasive, sensitive, and reproducible tests can help to recognize these disorders and to better understand specific mechanisms of some, potentially treatable, immune-mediated autonomic neuropathies. This paper describes autonomic involvement in immune-mediated neuropathies with a subacute or chronic course.

Transthyretin-related familial amyloidotic polyneuropathy: description of a cohort of patients with Leu64 mutation and late onset.

Transthyretin-related familial amyloidotic polyneuropathy (TTR-FAP) usually presents itself as a progressive sensorimotor polyneuropathy with severe autonomic dysfunction and cardiomyopathy. Eighteen patients carrying the Leu64 mutation underwent a series of regular follow-ups, including: neurological examination, electroneurography, electromyography, electrocardiography and echocardiography, blood analysis, a questionnaire on autonomic symptoms, cardiovascular autonomic tests and a 99mTc-DPD examination study. A late onset of a slowly progressive disease which reached its terminal stage after about 10 years was observed. The onset was mainly a length-dependent sensory neuropathy, although a focal onset with carpal tunnel syndrome was detected in three patients. At the onset of the disease, autonomic dysfunction was present in a small number of patients, but, within a few years, this had manifested in all members of the sample group. The only extra-neurological manifestations were cardiac related. It is reasonable to consider Southern Italy as an endemic focus of TTR-FAP. An underestimation of disease prevalence could be caused by a late onset of FAP, which can manifest in patients up to their late 70s. Follow-up of asymptomatic individuals may permit the early detection of symptoms and signs, allowing a detailed record of the natural history of the disease from the beginning and facilitating prompt treatment.

Unusual features of central nervous system involvement in CMTX associated with a novel mutation of GJB1 gene.

In this study, we report a novel connexin 32 (CX32) mutation associated with cognitive impairment and a differential degree of peripheral nerve involvement. We present clinical, electrophysiological, and neuroimaging data on a family with X-linked Charcot-Marie-Tooth disease caused by a 41A>G mutation of the gap junction protein beta 1 (GJB1) gene. The proband and her sister presented with a severe neuropathy with subclinical cognitive impairment; the proband's brother showed severe cognitive impairment and a mild neuropathy. This family report confirms that Charcot-Marie-Tooth type X is a clinically heterogeneous group, with great variability of phenotypes, possible severe involvement in females and clinical signs of cognitive impairment. Thus, this novel mutation should be added to the group of CX32 mutations with a central nervous system phenotype.