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Loss-of-function mutations in TTC19 (tetra-tricopeptide repeat domain 19) have been associated with severe neurological phenotypes and mitochondrial respiratory chain complex III deficiency. We previously demonstrated the mitochondrial localization of TTC19 and its link with complex III biogenesis. Here we provide detailed insight into the mechanistic role of TTC19, by investigating a Ttc19?/? mouse model that shows progressive neurological and metabolic decline, decreased complex III activity, and increased production of reactive oxygen species. By using both the Ttc19?/? mouse model and a range of human cell lines, we demonstrate that TTC19 binds to the fully assembled complex III dimer, i.e., after the incorporation of the iron-sulfur Rieske protein (UQCRFS1). The in situ maturation of UQCRFS1 produces N-terminal polypeptides, which remain bound to holocomplex III. We show that, in normal conditions, these UQCRFS1 fragments are rapidly removed, but when TTC19 is absent they accumulate within complex III, causing its structural and functional impairment.
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Complejo III de Transporte de Electrones/metabolismo , Proteínas Hierro-Azufre/metabolismo , Proteínas de la Membrana/metabolismo , Mitocondrias/enzimología , Proteínas Mitocondriales/metabolismo , Animales , Conducta Animal , Modelos Animales de Enfermedad , Complejo III de Transporte de Electrones/deficiencia , Complejo III de Transporte de Electrones/genética , Femenino , Genotipo , Células HeLa , Humanos , Proteínas Hierro-Azufre/genética , Cinética , Masculino , Proteínas de la Membrana/genética , Ratones Endogámicos C57BL , Ratones Noqueados , Enfermedades Mitocondriales , Proteínas Mitocondriales/genética , Actividad Motora , Degeneración Nerviosa , Sistema Nervioso/metabolismo , Sistema Nervioso/patología , Sistema Nervioso/fisiopatología , Fenotipo , Unión Proteica , Estabilidad Proteica , Proteolisis , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Pompe disease (PD) is a monogenic autosomal recessive disorder caused by biallelic pathogenic variants of the GAA gene encoding lysosomal alpha-glucosidase; its loss causes glycogen storage in lysosomes, mainly in the muscular tissue. The genotype-phenotype correlation has been extensively discussed, and caution is recommended when interpreting the clinical significance of any mutation in a single patient. As there is no evidence that environmental factors can modulate the phenotype, the observed clinical variability in PD suggests that genetic variants other than pathogenic GAA mutations influence the mechanisms of muscle damage/repair and the overall clinical picture. Genes encoding proteins involved in glycogen synthesis and catabolism may represent excellent candidates as phenotypic modifiers of PD. The genes analyzed for glycogen synthesis included UGP2, glycogenin (GYG1-muscle, GYG2, and other tissues), glycogen synthase (GYS1-muscle and GYS2-liver), GBE1, EPM2A, NHLRC1, GSK3A, and GSK3B. The only enzyme involved in glycogen catabolism in lysosomes is α-glucosidase, which is encoded by GAA, while two cytoplasmic enzymes, phosphorylase (PYGB-brain, PGL-liver, and PYGM-muscle) and glycogen debranching (AGL) are needed to obtain glucose 1-phosphate or free glucose. Here, we report the potentially relevant variants in genes related to glycogen synthesis and catabolism, identified by whole exome sequencing in a group of 30 patients with late-onset Pompe disease (LOPD). In our exploratory analysis, we observed a reduced number of variants in the genes expressed in muscles versus the genes expressed in other tissues, but we did not find a single variant that strongly affected the phenotype. From our work, it also appears that the current clinical scores used in LOPD do not describe muscle impairment with enough qualitative/quantitative details to correlate it with genes that, even with a slightly reduced function due to genetic variants, impact the phenotype.
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BACKGROUND AND PURPOSE: Many single cases and small series of Guillain-Barré syndrome (GBS) associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection were reported during the coronavirus disease 19 (COVID-19) outbreak worldwide. However, the debate regarding the possible role of infection in causing GBS is still ongoing. This multicenter study aimed to evaluate epidemiological and clinical findings of GBS diagnosed during the COVID-19 pandemic in northeastern Italy in order to further investigate the possible association between GBS and COVID-19. METHODS: Guillain-Barré syndrome cases diagnosed in 14 referral hospitals from northern Italy between March 2020 and March 2021 were collected and divided into COVID-19-positive and COVID-19-negative. As a control population, GBS patients diagnosed in the same hospitals from January 2019 to February 2020 were considered. RESULTS: The estimated incidence of GBS in 2020 was 1.41 cases per 100,000 persons/year (95% confidence interval 1.18-1.68) versus 0.89 cases per 100,000 persons/year (95% confidence interval 0.71-1.11) in 2019. The cumulative incidence of GBS increased by 59% in the period March 2020-March 2021 and, most importantly, COVID-19-positive GBS patients represented about 50% of the total GBS cases with most of them occurring during the two first pandemic waves in spring and autumn 2020. COVID-19-negative GBS cases from March 2020 to March 2021 declined by 22% compared to February 2019-February 2020. CONCLUSIONS: Other than showing an increase of GBS in northern Italy in the "COVID-19 era" compared to the previous year, this study emphasizes how GBS cases related to COVID-19 represent a significant part of the total, thus suggesting a relation between COVID-19 and GBS.
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COVID-19 , Síndrome de Guillain-Barré , COVID-19/complicaciones , COVID-19/epidemiología , Síndrome de Guillain-Barré/etiología , Humanos , Incidencia , Pandemias , SARS-CoV-2RESUMEN
OBJECTIVE: Single cases and small series of Guillain-Barré syndrome (GBS) have been reported during the SARS-CoV-2 outbreak worldwide. We evaluated incidence and clinical features of GBS in a cohort of patients from two regions of northern Italy with the highest number of patients with COVID-19. METHODS: GBS cases diagnosed in 12 referral hospitals from Lombardy and Veneto in March and April 2020 were retrospectively collected. As a control population, GBS diagnosed in March and April 2019 in the same hospitals were considered. RESULTS: Incidence of GBS in March and April 2020 was 0.202/100 000/month (estimated rate 2.43/100 000/year) vs 0.077/100 000/month (estimated rate 0.93/100 000/year) in the same months of 2019 with a 2.6-fold increase. Estimated incidence of GBS in COVID-19-positive patients was 47.9/100 000 and in the COVID-19-positive hospitalised patients was 236/100 000. COVID-19-positive patients with GBS, when compared with COVID-19-negative subjects, showed lower MRC sum score (26.3±18.3 vs 41.4±14.8, p=0.006), higher frequency of demyelinating subtype (76.6% vs 35.3%, p=0.011), more frequent low blood pressure (50% vs 11.8%, p=0.017) and higher rate of admission to intensive care unit (66.6% vs 17.6%, p=0.002). CONCLUSIONS: This study shows an increased incidence of GBS during the COVID-19 outbreak in northern Italy, supporting a pathogenic link. COVID-19-associated GBS is predominantly demyelinating and seems to be more severe than non-COVID-19 GBS, although it is likely that in some patients the systemic impairment due to COVID-19 might have contributed to the severity of the whole clinical picture.
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COVID-19/complicaciones , Síndrome de Guillain-Barré/epidemiología , Adulto , Anciano , COVID-19/diagnóstico , COVID-19/terapia , Femenino , Síndrome de Guillain-Barré/diagnóstico , Síndrome de Guillain-Barré/terapia , Hospitalización , Humanos , Incidencia , Italia , Masculino , Persona de Mediana Edad , Derivación y Consulta , Estudios RetrospectivosRESUMEN
INTRODUCTION/AIMS: Paramyotonia congenita (PMC) is a skeletal muscle sodium channelopathy characterized by paradoxical myotonia, cold sensitivity, and exercise/cold-induced paralysis. Treatment with sodium-channel-blocking antiarrhythmic agents may expose patients to a risk of arrhythmia or may be poorly tolerated or ineffective. In this study we explored the effectiveness of non-antiarrhythmic sodium-channel blockers in two patients with PMC. METHODS: Earlier treatment with mexiletine was discontinued for gastrointestinal side effects in one of the patients and lack of clinical benefit in the other. One patient received lacosamide, ranolazine, and buprenorphine, and the other was given buprenorphine only. Drug efficacy was assessed by clinical scores, timed tests, and by long and short exercise tests. RESULTS: In both patients, buprenorphine improved pain scores by at least 50%, stiffness and weakness levels, and handgrip/eyelid-opening times. The fall in compound muscle action potential (CMAP) during short exercise normalized in both patients at baseline, and improved after cooling. During long exercise, one patient showed an earlier recovery of CMAP, and the other patient had a less severe decrease (<60%). With buprenorphine, the fall in CMAP induced by cooling normalized in one patient (from -72% to -4%) and improved (from -49% to -37%) in the other patient. DISCUSSION: Buprenorphine showed promising results for the treatment of exercise-induced paralysis and cold intolerance in the two patients assessed. The exercise test may be useful for quantitative assessment of treatment response. Further studies on a larger number of patients, under carefully controlled conditions, should be considered to address the effectiveness and long-term tolerability of this therapeutic option.
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Analgésicos Opioides/uso terapéutico , Buprenorfina/uso terapéutico , Trastornos Miotónicos/diagnóstico , Trastornos Miotónicos/tratamiento farmacológico , Analgésicos Opioides/farmacología , Buprenorfina/farmacología , Prueba de Esfuerzo/efectos de los fármacos , Prueba de Esfuerzo/métodos , Humanos , Masculino , Persona de Mediana Edad , Trastornos Miotónicos/genética , Canal de Sodio Activado por Voltaje NAV1.4/genética , Resultado del TratamientoRESUMEN
INTRODUCTION/AIMS: Coronavirus disease 2019 (COVID-19), a disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, has become a global pandemic. Patients with myasthenia gravis (MG), often treated with immunosuppressants, might be at higher risk of developing COVID-19 and of demonstrating a severe disease course. We aimed to study prevalence and describe features of COVID-19 in MG patients. METHODS: In May 2020, we conducted telephonic interviews with MG patients followed at our referral center. We collected structured data regarding MG and COVID-19, which was diagnosed as probable or confirmed according to the European Centre for Disease Prevention and Control case definition. We compared confirmed-COVID-19 prevalence calculated from the beginning of the pandemic in MG patients with that of the overall Pavia district. RESULTS: We interviewed 162 MG patients (median age, 66 y; interquartile range 41-77; males 59.9%), 88 from the Pavia district. Three patients had SARS-CoV-2-confirmed by polymerase chain reaction and eight had probable-COVID-19. In the Pavia district, the prevalence of confirmed-COVID-19 among MG patients (1/88, 1.14%) and overall population (4777/546 515, 0.87%) did not differ (P = .538). Higher Myasthenia Gravis Foundation of America clinicalclass and the need for recent rescue treatment, but not ongoing immunosuppressive treatments, were associated with COVID-19 risk. Of 11 MG patients with probable/confirmed-COVID-19, 3 required ventilator support, and 2 elderly patients died of COVID-19 respiratory insufficiency. Only 1 of11 patients experienced worsening MG symptoms, which improved after increasing their steroid dose. DISCUSSION: The risk of COVID-19 in MG patients seems to be no higher than that of the general population, regardless of immunosuppressive therapies. In our cohort, COVID-19 barely affected MG course.
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COVID-19/diagnóstico , COVID-19/epidemiología , Progresión de la Enfermedad , Miastenia Gravis/diagnóstico , Miastenia Gravis/epidemiología , Anciano , Anciano de 80 o más Años , Prueba de Ácido Nucleico para COVID-19/métodos , Femenino , Humanos , Inmunosupresores/administración & dosificación , Masculino , Persona de Mediana Edad , Miastenia Gravis/tratamiento farmacológicoRESUMEN
BACKGROUND: Transient global amnesia (TGA) is a clinical syndrome characterized by a temporary short-term memory loss with inability to retain new memories, usually lasting 2 to 8 h. TGA may be related to several medical procedures, including angiography, general anesthesia, gastroscopy. CASE PRESENTATION: We report a 58-year-old woman who experiencing TGA one hour after the execution of her first-time nasopharyngeal swab for COVID-19. Brain MRI showed a typical punctate Diffusion Weight Image (DWI) hippocampal lesion. CONCLUSIONS: This is the first report of TGA after the execution of nasopharyngeal swab for COVID-19. This association lengthen the list of medical procedures associated with TGA, and we discuss the possible plausible mechanisms by which a nasopharyngeal swab could trigger TGA.
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Amnesia Global Transitoria , COVID-19/diagnóstico , Manejo de Especímenes/efectos adversos , Amnesia Global Transitoria/diagnóstico , Amnesia Global Transitoria/etiología , Prueba de COVID-19 , Femenino , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Nasofaringe/virologíaRESUMEN
BACKGROUND: The mechanisms of genotype-phenotype interaction in Familiar Hemiplegic migraine type 2 (FHM2) are still far from clear. Different ATP1A2 mutations have been described, with a spectrum of phenotypes ranging from mild to severe. No genotype-phenotype correlations have been attempted. CASE PRESENTATION: We describe an Italian family with FHM and a missense ATP1A2 variant (L425H) not previously described. The clinical picture was mild in all the affected members. CONCLUSIONS: Co-segregation of the variant with the aura phenotype was complete in this family, suggesting a 100% penetrance. In silico protein prediction softwares indicate that this variant may change the 3D structure of ATPA1A2 at the cytoplasmic loop between the two central transmembrane helices. Milder FHM phenotypes are rarely reported in literature, likely because case reports are biased towards the most severe phenotypes, with milder forms possibly misdiagnosed as sporadic migraine with aura forms (MAs), even with complex auras. Further studies taking into account intra-familiar variability and functional consequences on the channel protein may help clarify genotype-phenotype correlations.
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Migraña con Aura , Humanos , Italia , Migraña con Aura/genética , Mutación , Mutación Missense , Linaje , ATPasa Intercambiadora de Sodio-Potasio/genéticaAsunto(s)
Infecciones por Coronavirus/complicaciones , Síndrome de Guillain-Barré/etiología , Neumonía Viral/complicaciones , Anciano , Betacoronavirus , COVID-19 , Infecciones por Coronavirus/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/terapia , SARS-CoV-2 , Capacidad Vital , Adulto JovenRESUMEN
Non-dystrophic myotonias are characterized by clinical overlap making it challenging to establish genotype-phenotype correlations. We report clinical and electrophysiological findings in a girl and her father concomitantly harbouring single heterozygous mutations in SCN4A and CLCN1 genes. Functional characterization of N1297S hNav1.4 mutant was performed by patch clamp. The patients displayed a mild phenotype, mostly resembling a sodium channel myotonia. The CLCN1 c.501C>G (p.F167L) mutation has been already described in recessive pedigrees, whereas the SCN4A c.3890A>G (p.N1297S) variation is novel. Patch clamp experiments showed impairment of fast and slow inactivation of the mutated Nav1.4 sodium channel. The present findings suggest that analysis of both SCN4A and CLCN1 genes should be considered in myotonic patients with atypical clinical and neurophysiological features.
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Canales de Cloruro/genética , Mutación/genética , Miotonía/genética , Canal de Sodio Activado por Voltaje NAV1.4/genética , Adulto , Femenino , Estudios de Asociación Genética/métodos , Heterocigoto , Humanos , Miotonía/diagnóstico , Linaje , FenotipoRESUMEN
Enzyme replacement therapy is currently the only approved treatment for Pompe disease, due to acid α-glucosidase deficiency. Clinical efficacy of this approach is variable, and more effective therapies are needed. We showed in preclinical studies that chaperones stabilize the recombinant enzyme used for enzyme replacement therapy. Here, we evaluated the effects of a combination of enzyme therapy and a chaperone on α-glucosidase activity in Pompe disease patients. α-Glucosidase activity was analyzed by tandem-mass spectrometry in dried blood spots from patients treated with enzyme replacement therapy, either alone or in combination with the chaperone N-butyldeoxynojirimycin given at the time of the enzyme infusion. Thirteen patients with different presentations (3 infantile-onset, 10 late-onset) were enrolled. In 11 patients, the combination treatment resulted in α-glucosidase activities greater than 1.85-fold the activities with enzyme replacement therapy alone. In the whole patient population, α-glucosidase activity was significantly increased at 12 hours (2.19-fold, P = 0.002), 24 hours (6.07-fold, P = 0.001), and 36 hours (3.95-fold, P = 0.003). The areas under the curve were also significantly increased (6.78-fold, P = 0.002). These results suggest improved stability of recombinant α-glucosidase in blood in the presence of the chaperone.
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1-Desoxinojirimicina/análogos & derivados , Enfermedad del Almacenamiento de Glucógeno Tipo II/sangre , Enfermedad del Almacenamiento de Glucógeno Tipo II/tratamiento farmacológico , Inhibidores de Glicósido Hidrolasas/farmacología , alfa-Glucosidasas/farmacología , 1-Desoxinojirimicina/farmacología , Adolescente , Adulto , Animales , Niño , Preescolar , Modelos Animales de Enfermedad , Pruebas con Sangre Seca , Sinergismo Farmacológico , Terapia de Reemplazo Enzimático/métodos , Estabilidad de Enzimas , Femenino , Humanos , Masculino , Ratones , Persona de Mediana Edad , Adulto Joven , alfa-Glucosidasas/sangre , alfa-Glucosidasas/uso terapéuticoRESUMEN
BACKGROUND AND OBJECTIVES: 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. METHODS: 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. RESULTS: 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. DISCUSSION: 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.
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Miopatías Distales , Miopatías Estructurales Congénitas , Humanos , Femenino , Masculino , Persona de Mediana Edad , Italia , Adulto , Miopatías Distales/genética , Miopatías Distales/patología , Miopatías Distales/epidemiología , Estudios Retrospectivos , Anciano , Miopatías Estructurales Congénitas/genética , Miopatías Estructurales Congénitas/patologíaRESUMEN
PURPOSE: Type II glycogenosis (GSDII) is a rare and often fatal neuromuscular disorder caused by acid alpha-glucosidase deficiency. Although alglucosidase alfa enzyme replacement therapy (ERT) significantly improves outcomes in subjects with the infantile form, its efficacy in patients with the late-onset one is not entirely clear. The long-term efficacy of ERT in late-onset GSGII complicated by severe pulmonary impairment causing high mechanical ventilation dependency was investigated in this study. METHODS: The long-term clinical efficacy of ERT was assessed in eight late-onset GSDII patients using home mechanical ventilation (HMV) by comparing their outcomes with those of six historical control patients (GSDII patients) who had received HMV alone. The number of hospitalizations due to pulmonary exacerbations and of hours of daily use of HMV were considered the study's primary efficacy endpoints. RESULTS: The treatment group showed an increased tendency toward shorter follow-up compared to the control group (35.8 ± 29.2 vs. 52.6 ± 8.55 months; p = 0.04). At the end of the study period, the daily use of HMV (12.5 ± 7.6 vs. 19 ± 14.3 h; p = 0.004) and the hospitalization rate [incidence rate ratio = 0.43 (95 % confidence interval 0.18-0.93); p = 0.03] were significantly lower in the patients receiving ERT. The differences in the forced vital capacity absolute value and percentage change from baseline were not significantly different in the two groups. CONCLUSIONS: ERT reduces ventilator dependency in late-onset GSDII patients and the need for hospitalization due to respiratory exacerbations.
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Terapia de Reemplazo Enzimático , Enfermedad del Almacenamiento de Glucógeno Tipo II/tratamiento farmacológico , Enfermedades Pulmonares/terapia , Respiración Artificial , Mecánica Respiratoria/fisiología , alfa-Glucosidasas/uso terapéutico , Adolescente , Adulto , Edad de Inicio , Anciano , Atención Ambulatoria , Comorbilidad , Femenino , Estudios de Seguimiento , Enfermedad del Almacenamiento de Glucógeno Tipo II/epidemiología , Hospitalización/estadística & datos numéricos , Humanos , Incidencia , Enfermedades Pulmonares/epidemiología , Enfermedades Pulmonares/fisiopatología , Masculino , Persona de Mediana Edad , Mecánica Respiratoria/efectos de los fármacos , Resultado del Tratamiento , alfa-Glucosidasas/farmacologíaRESUMEN
BACKGROUND: The Italian Medicines Agency (AIFA) demands precise information on benefit/risk profile of home-based enzyme replacement therapy (ERT) for the treatment of patients with Pompe disease and Mucopolysaccharidosis type I (MPS I). This passage is necessary to obtain the authorization for ERT home therapy, even after the coronavirus disease-19 (COVID-19) pandemic period. This research intends to evaluate the safety, treatment satisfaction, and compliance of MPS I patients treated with laronidase (Aldurazyme®) and Pompe Disease patients treated with alglucosidase alfa (Myozyme®) in a homecare setting. RESULTS: We report herein an early interim analysis of the HomERT (Home infusions of ERT) study, a multicenter, non-interventional, double-cohort study that retrospectively analyzed 38 patients from 14 sites in Italy: cohort A (Pompe disease - 32 patients) and cohort B (MPS I - 6 patients). Among the selected patients who started home therapy before enrollment, the average number of missed home-based infusions was 0.7 (1.3) in cohort A and 3.8 (6.4) in cohort B with no return to the hospital setting. Irrespective of the treatment location, 3 prior ADRs per cohort were reported. The majority of patients preferred home-based infusions (cohort A: 96.9%; cohort B: 100%): the main reason was attributed to treatment convenience (cohort A: 81.3%; cohort B: 83.3%). Despite the underlying conditions, most patients self-evaluated their health as "good" (cohort A: 50%; cohort B: 83.3%). CONCLUSIONS: Evidence of favorable safety profile, improved treatment compliance and personal satisfaction validates the use of ERT with laronidase and alglucosidase alfa as a strong candidate for home therapy.
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COVID-19 , Enfermedad del Almacenamiento de Glucógeno Tipo II , Mucopolisacaridosis I , Mucopolisacaridosis VI , Humanos , Terapia de Reemplazo Enzimático/efectos adversos , Mucopolisacaridosis I/tratamiento farmacológico , Estudios de Cohortes , Estudios Retrospectivos , Prioridad del Paciente , alfa-GlucosidasasRESUMEN
Facioscapulohumeral muscular dystrophy (FSHD) is the second most common muscular dystrophy in adults, and it is associated with local D4Z4 chromatin relaxation, mostly via the contraction of the D4Z4 macrosatellite repeat array on chromosome 4q35. In this study, we aimed to investigate the use of Optical Genome Mapping (OGM) as a diagnostic tool for testing FSHD cases from the UK and India and to compare OGM performance with that of traditional techniques such as linear gel (LGE) and Pulsed-field gel electrophoresis (PFGE) Southern blotting (SB). A total of 6 confirmed and 19 suspected FSHD samples were processed with LGE and PFGE, respectively. The same samples were run using a Saphyr Genome-Imaging Instrument (1-color), and the data were analysed using custom EnFocus FSHD analysis. OGM was able to confirm the diagnosis of FSHD1 in all FSHD1 cases positive for SB (n = 17), and D4Z4 sizing highly correlated with PFGE-SB (p < 0.001). OGM correctly identified cases with mosaicism for the repeat array contraction (n = 2) and with a duplication of the D4Z4 repeat array. OGM is a promising new technology able to unravel structural variants in the genome and seems to be a valid tool for diagnosing FSHD1.
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Distrofia Muscular Facioescapulohumeral , Adulto , Humanos , Distrofia Muscular Facioescapulohumeral/diagnóstico , Distrofia Muscular Facioescapulohumeral/genética , Electroforesis en Gel de Campo Pulsado , Mapeo Cromosómico , IndiaRESUMEN
The purpose of this study is to analyze the role of genes known to influence muscle performances on the outcome after enzyme replacement treatment (ERT) in type II Glycogenosis (GSDII). We analyzed 16 patients receiving ERT for ≥two years. We assessed the changes in muscle strength by hand-held dynamometry, muscle mass by quantitative MRI, and resistance to exercise by the 6-minute walking test. Exercise gene assessment included angiotensin converting enzyme insertion/deletion polymorphism (ACE), alpha-actinin3 R577X polymorphism (ACTN3), and peroxisome proliferator activated receptor alpha G/C polymorphism (PPARα). Independent of disease severity, one third of patients had a poor response to ERT, which was found to be associated with ACE DD genotype. The ACTN3 null polymorphism appeared to exert a positive effect on treatment efficacy, while PPARα did not seem to exert any influence at all. We conclude that poor treatment outcome in ACE DD genotypes is in line with previous observation of a worse disease course in this subpopulation, and suggests the need for a more careful follow-up and individualized treatment approaches for these patients. Exercise genes may provide a new opportunity for studying the outcome after treatment and the muscle regeneration abilities in other models of genetic myopathies.
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Terapia de Reemplazo Enzimático , Enfermedad del Almacenamiento de Glucógeno Tipo II/genética , Enfermedad del Almacenamiento de Glucógeno Tipo II/terapia , Músculo Esquelético/metabolismo , Actinina/genética , Adulto , Edad de Inicio , Anciano , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , PPAR alfa/genética , Peptidil-Dipeptidasa A/genética , Polimorfismo Genético , Resultado del TratamientoRESUMEN
Glycogen storage disease type II (GSD II), also known as Pompe disease, is an autosomal recessive inherited disorder caused by a reduced activity of acid alpha glucosidase (GAA). Two different clinical entities have been described: rapidly fatal infantile and late onset forms. Hearing loss has been described in classic infantile Pompe patients but rarely in late onset cases. The main purpose of this study was to investigate the involvement of the auditory system in a cohort of Italian patients with late onset GSD II. We have enrolled 20 patients, 12 males and 8 females. The auditory system assessment included speech and pure tone audiometry, impedance audiometry and auditory brainstem responses (ABR). A combined interpretation of those tests allowed us to define the origin of the hearing impairment (sensorineural, conductive or mixed). Clinically, all patients but one denied subjective hearing disturbances. On the other hand, audiological evaluation revealed that 21/40 patient ears (52.5%) had a hearing impairment: 57% had a sensorineural deficit, 33% showed a conductive hearing loss whereas 10% presented with a mixed pattern. Our study revealed that, in this group of GSDII late onset patients, the auditory system impairment was more frequently present than thought with a prominent cochlear involvement. Our results emphasize the importance of a routinely auditory function evaluation in all forms of Pompe disease.
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Cóclea/patología , Enfermedad del Almacenamiento de Glucógeno Tipo II/patología , Pérdida Auditiva Conductiva/patología , Pérdida Auditiva Sensorineural/patología , Pruebas de Impedancia Acústica , Adolescente , Adulto , Edad de Inicio , Anciano , Audiometría de Tonos Puros , Niño , Cóclea/fisiopatología , Potenciales Evocados Auditivos del Tronco Encefálico , Femenino , Glucógeno/metabolismo , Enfermedad del Almacenamiento de Glucógeno Tipo II/metabolismo , Enfermedad del Almacenamiento de Glucógeno Tipo II/fisiopatología , Audición/fisiología , Pérdida Auditiva Conductiva/fisiopatología , Pérdida Auditiva Sensorineural/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , alfa-Glucosidasas/metabolismoRESUMEN
INTRODUCTION: The clinical course of late-onset Pompe disease is heterogeneous, and new clinical outcome measures are needed to evaluate enzyme replacement therapy (ERT). METHODS: We correlated the 6-Minute Walk Test (6MWT), Walton and Gardner-Medwin (WGM) score, and GSGC (Gait, Stairs, Gower, Chair) scores in 40 patients. RESULTS: At baseline, the GSGC score correlated with both WGM (P < 0.001, n = 33) and 6MWT (P < 0.001, n = 26). After 1 year of ERT, we observed a significant change in gait, stairs and chair performance on the GSGC scale. The 6MWT significantly increased from 319 to 371 meters in 32 patients, and the WGM score was reduced. CONCLUSIONS: GSGC is a group of functional tests that requires only a few minutes to perform, therefore, this score might be a good indicator to be used in future studies.
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Evaluación de la Discapacidad , Terapia de Reemplazo Enzimático , Enfermedad del Almacenamiento de Glucógeno Tipo II/tratamiento farmacológico , Enfermedad del Almacenamiento de Glucógeno Tipo II/epidemiología , Actividad Motora/fisiología , Evaluación de Resultado en la Atención de Salud , Adulto , Edad de Inicio , Anciano , Femenino , Estudios de Seguimiento , Marcha/fisiología , Enfermedad del Almacenamiento de Glucógeno Tipo II/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Caminata/fisiologíaRESUMEN
BACKGROUND: The syndrome of transient Headache and Neurological Deficits with cerebrospinal fluid (CSF) Lymphocytosis (HaNDL) is classified among secondary headaches attributed to "non-infectious, inflammatory intracranial disease". Despite its classification among secondary headaches, the current definition of HaNDL does not contemplate a causal agent. Thus, the aetiology, as well as the pathogenesis of both the headache and the transient focal deficits, remains unknown. CASE PRESENTATION: We describe a 29-year-old healthy male developing episodes of thunderclap headaches associated with recurrence of hemiparesis/hemi-paraesthesia; CSF showed lymphocytosis 200/mm3 and increased albumin; brain MRI revealed widespread leptomeningeal enhancement and a non-enhancing, circular diffusion restriction in the splenium of corpus callosum. Screening for neurotropic pathogens detected Epstein-Barr (EBV) DNA in serum and CSF, interpreted as a primary EBV infection once the seroconversion of EBV nuclear antigen (EBNA) IgM to IgG was proven on follow-up. Transcranial Doppler detected, during headache, increased flow velocity in middle cerebral arteries, possibly indicating vasospasm. Oral nimodipine was administered, with prompt clinical recovery, resolution of CSF/MRI abnormalities, and normalization of flow velocities in middle cerebral arteries. CASE-BASED REVIEW: Although the definition of HaNDL does not contemplate a viral trigger or abnormal brain imaging, we found other literature cases of HaNDL associated with direct or indirect signs of CNS infection. CONCLUSIONS: At least in a proportion of patients, a viral aetiology may have a role in HaNDL. Whatever the aetiology, we suggest that the pathogenic mechanism may rely on the (viral or other) agent ultimately triggering cerebral vasoconstriction, which would explain both focal symptoms and headache. Calcium channel blockers might be a therapeutic option.