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Emery-Dreifuss muscular dystrophy (EDMD) is a rare disease characterized by early contractures, progressive muscle weakness, and cardiac abnormalities. Different subtypes of EDMD have been described, with the two most common forms represented by the X-linked EDMD1, caused by mutations in the EMD gene encoding emerin, and the autosomal EDMD2, due to mutations in the LMNA gene encoding lamin A/C. A clear definition of the magnetic resonance imaging (MRI) pattern in the two forms, and especially in the rarer EDMD1, is still lacking, although a preferential involvement of the medial head of the gastrocnemius has been suggested in EDMD2. We report a 13-year-old boy with mild limb girdle muscle weakness, elbow and ankle contractures, with absence of emerin at muscle biopsy, carrying a hemizygous frameshift mutation on the EMD gene (c.153dupC/p.Ser52Glufs*9) of maternal inheritance. Minor cardiac rhythm abnormalities were detected at 24-hour Holter electrocardiogram and required β-blocker therapy. MRI scan of the thighs showed a mild diffuse involvement, while tibialis anterior, extensor digitorum longus, peroneus longus, and medial gastrocnemius were the most affected muscles in the leg. We also provide a review of the muscular MRI data in EDMD patients and highlight the relative heterogeneity of the MRI patterns found in EDMDs, suggesting that muscle MRI should be studied in larger EDMD cohorts to better define disease patterns and to cover the wide disease spectrum.

SPTLC1-related disorder is a late onset sensory-autonomic neuropathy associated with perturbed sphingolipid homeostasis which can be improved by supplementation with the serine palmitoyl-CoA transferase (SPT) substrate, l-serine. Recently, a juvenile form of motor neuron disease has been linked to SPTLC1 variants. Variants affecting the p.S331 residue of SPTLC1 cause a distinct phenotype, whose pathogenic basis has not been established. This study aims to define the neuropathological and biochemical consequences of the SPTLC1 p.S331 variant, and test response to l-serine in this specific genotype.We report clinical and neurophysiological characterisation of two unrelated children carrying distinct p.S331 SPTLC1 variants. The neuropathology was investigated by analysis of sural nerve and skin innervation. To clarify the biochemical consequences of the p.S331 variant, we performed sphingolipidomic profiling of serum and skin fibroblasts. We also tested the effect of l-serine supplementation in skin fibroblasts of patients with p.S331 mutations.In both patients, we recognised an early onset phenotype with prevalent progressive motor neuron disease. Neuropathology showed severe damage to the sensory and autonomic systems. Sphingolipidomic analysis showed the coexistence of neurotoxic deoxy-sphingolipids with an excess of canonical products of the SPT enzyme. l-serine supplementation in patient fibroblasts reduced production of toxic 1-deoxysphingolipids but further increased the overproduction of sphingolipids.Our findings suggest that p.S331 SPTLC1 variants lead to an overlap phenotype combining features of sensory and motor neuropathies, thus proposing a continuum in the spectrum of SPTLC1-related disorders. l-serine supplementation in these patients may be detrimental.

Genetic modifiers of Duchenne muscular dystrophy (DMD) are variants located in genes different from the disease-causing gene DMD, but associated with differences in disease onset, progression, or response to treatment. Modifiers described so far have been tested mainly for associations with ambulatory function, while their effect on upper limb function, which is especially relevant for quality of life and independence in non-ambulatory patients, is unknown. We tested genotypes at several known modifier loci (SPP1, LTBP4, CD40, ACTN3) for association with Performance Upper Limb version 1.2 score in an Italian multicenter cohort, and with Brooke scale score in the Cooperative International Neuromuscular Group Duchenne Natural History Study (CINRG-DNHS), using generalized estimating equation (GEE) models of longitudinally collected data, with age and glucocorticoid treatment as covariates. CD40 rs1883832, previously linked to earlier loss of ambulation, emerged as a modifier of upper limb function, negatively affecting shoulder and distal domains of PUL (p = 0.023 and 0.018, respectively) in the Italian cohort, as well as of Brooke score (p = 0.018) in the CINRG-DNHS. These findings will be useful for the design and interpretation of clinical trials in DMD, especially for non-ambulatory populations.

The role of muscle biopsy in the diagnostic workup of floppy infants is controversial. Muscle sampling is invasive, and often, results are not specific. The rapid expansion of genetic approach has made the muscle histopathology analysis less crucial. This study aims to assess the role and efficacy of muscle histopathology in the diagnostic algorithm of hypotonia in early infancy through a retrospective analysis of 197 infants who underwent muscle biopsy in their first 18 months of life. Data analysis revealed that 92/197 (46.7%) of muscle biopsies were non-specific (80) or normal (12), not allowing a specific diagnosis. In 41/197 (20.8%) cases, biopsy suggested a metabolic or mitochondrial myopathy, while in 23/197 cases (11.7%), we found evidence of muscular dystrophy. In 19/197 cases (9.7%), histopathology characteristics of a congenital myopathy were reported. In 22/197 cases (11.7%), the histopathological study indicated presence of a neurogenic damage. Overall, 46 diagnoses were then achieved by oriented genetic tests. Muscle biopsy results were consistent with genetic results in 90% of cases. Diagnostic algorithms for the diagnosis of a floppy infant are largely missing. Muscle biopsy alone can lead to a diagnosis, help the clinician in the choice of a genetic test, or even modify a diagnosis made previously.

Il progetto di studio delle mummie di Roccapelago, nato in seguito al ritrovamento, nella cripta della locale chiesa della Conversione di San Paolo Apostolo, dei resti di oltre 400 individui, molti dei quali parzialmente mummificati, ha previsto, fin dall’inizio, un approccio multidisciplinare volto all'integrazione dei risultati scaturiti dalle indagini archeoantropologiche, paleodemografiche e paleopatologiche con quelli prodotti dalle analisi genetiche dei reperti. A questo scopo è stato programmato, tra l’altro, anche uno studio diacronico del DNA finalizzato a indagare la struttura e le dinamiche della popolazione di Roccapelago nell’arco di circa quattro secoli, cioè dalla fase più antica di uso sepolcrale della cripta fino alla comunità attualmente vivente. La selezione dei campioni oggetto dello studio ha perciò riguardato sia i reperti antichi, risalenti a un periodo compreso tra il XVI e il XVIII secolo, sia membri attuali della comunità locale.

The aim of this retrospective study was to review body mass index (BMI) in a large cohort of Italian pediatric type 2 spinal muscular atrophy (SMA) patients, aged between 0 and 20 years and to establish possible differences in relation to a number of variables such as ventilation, motor function, and survival motor neuron 2 gene copies. Cross-sectional data were collected from 102 patients for a total of 344 visits. Standard growth charts for height and weight were used as reference, with age adjusted BMI calculated using the Center for Disease and Prevention Children’s BMI Tool. In the 344 visits, weight ranged between 3.90 and 83 kg, and the BMI between 8.4 and 31.6 with a BMI/age z-scores z-scores > + 2SD in 9% of the measurements. The BMI/age z-scores were relatively stable z-scores after the age of 13. A difference on the BMI/age z-scores was found among the different age subgroups (z-scores and gender were significantly contributing to the changes while other variables were not.Conclusion: Our results confirm that careful surveillance of weight and BMI/age z-scores is needed in type 2 SMA. Further studies, including assessments of chewing and swallowing and of lean/fat body mass, will help to better understand the possible mechanisms underlying weight issues. What is Known:• Feeding difficulties have been reported in a few studies and were invariably found in patients with type 1 SMA.• Type 2 SMA patients often have low BMI with a relevant number of patients requiring tube feeding. What is New:• Reduction in BMI/age z-score overtime appeared to depend on baseline BMI/age z-score and gender.• Patients with a low BMI/age z-score were at higher risk of developing further reduction.

Background Benign acute childhood myositis (BACM) is a self-limited syndrome associated with viral infections characterized by symmetric lower extremity pain typically affecting school-aged children. Evolution in rhabdomyolysis and kidney damage is rarely reported. Despite this, the acute presentation commonly concerns both parents and health care providers, often leading to unnecessary workup. The aim of the study was to determine the features and outcome of a large series of children with BACM identifying a management pathway for pediatricians in Emergency Department (ED). Methods We conducted a retrospective study of patients with BACM managed in 2 Italian pediatric ED during a period of 8 and a half years. Demographic data, clinical, and laboratory results were extracted from electronic medical records. Recurrence, complications, treatments, and outcomes were also recorded. Descriptive statistics were produced for first-episode patients and for those with recurrence of myositis. A comparison between groups was performed. Results One hundred and thirteen patients with BACM were identified. Ninety-two children (65 males) had a single episode, while ten (nine males) had recurrence. The mean age at presentation was 6.0 years (range 2–13,2). All patients had normal neurological examination and no one developed myoglobinuria, or renal failure. At first evaluation median CK level was 1413 UI/l (normal values Median CK of “recurrent” patients was higher than “non-recurrent” (2330 vs 1150 U/L, p = 0.009). Viral studies were positive in 51/74 cases, with high prevalence of Influenza viruses. Ninety-six patients (85%) were hospitalized with a median of 4 days. No patients had any residual muscular impairment. Conclusions BACM has an excellent prognosis. Severe pathological conditions can be excluded with a complete history and clinical examination and simple blood and urine tests, avoiding unnecessary diagnostic investigations. Most patients may be discharged home from ED recommending hydration, rest, analgesics and careful follow-up.

Aim Since the immune system plays a role in the pathogenesis of several muscular dystrophies, we aim to characterize several muscular inflammatory features in α- (LGMD R3) and γ-sarcoglycanopathies (LGMD R5). Materials and methods We explored the expression of major histocompatibility complex class I molecules (MHCI), and we analyzed the composition of the immune infiltrates in muscle biopsies from 10 patients with LGMD R3 and 8 patients with LGMD R5, comparing the results to Duchenne muscular dystrophy patients (DMD). Results A consistent involvement of the immune response was observed in sarcoglycanopathies, although it was less evident than in DMD. LGMD R3-R5 and DMD shared an abnormal expression of MHCI, and the composition of the muscular immune cell infiltrate was comparable. Conclusion These findings might serve as a rationale to fine-tune a disease-specific immunomodulatory regimen, particularly relevant in view of the rapid development of gene therapy for sarcoglycanopathies.

T lymphocytes play a central role in antigen-specific immune responses. They modulate the function of different immune cells both through a direct contact (receptor binding) and through the secretion of cytokines. At the same time, they are deeply involved in the direct killing of aberrant target cells. T lymphocytes derive from a bone marrow precursor that migrates in the thymus where the main differentiation steps take place. Mature CD4 and CD8 single-positive cells, then, leave the thymus to reach the secondary lymphoid organs. T-cell subsets and their maturation steps can be identified mainly based on the expression of extracellular markers, intracellular transcription factors and cytokine production profiles. In this review, we report, from a cytometric point of view, an overview of the most important T-cell subpopulations and their differentiation state. © 2020 International Society for Advancement of Cytometry.

Sarcoglycanopathies include four subtypes of autosomal recessive limb-girdle muscular dystrophies (LGMDR3, LGMDR4, LGMDR5 and LGMDR6) that are caused, respectively, by mutations in the SGCA, SGCB, SGCG and SGCD genes. Delta-sarcoglycanopathy (LGMDR6) is the least frequent and is considered an ultra-rare disease. Our aim was to characterize the clinical and genetic spectrum of a large international cohort of LGMDR6 patients and to investigate whether or not genetic or protein expression data could predict a disease's severity. This is a retrospective study collecting demographic, genetic, clinical and histological data of patients with genetically confirmed LGMDR6 including protein expression data from muscle biopsies. We contacted 128 paediatric and adult neuromuscular units around the world that reviewed genetic data of patients with a clinical diagnosis of a neuromuscular disorder. We identified 30 patients with a confirmed diagnosis of LGMDR6 of which 23 patients were included in this study. Eighty-seven per cent of the patients had consanguineous parents. Ninety-one per cent of the patients were symptomatic at the time of the analysis. Proximal muscle weakness of the upper and lower limbs was the most common presenting symptom. Distal muscle weakness was observed early over the course of the disease in 56.5% of the patients. Cardiac involvement was reported in five patients (21.7%) and four patients (17.4%) required non-invasive ventilation. Sixty per cent of patients were wheelchair-bound since early teens (median age of 12.0 years). Patients with absent expression of the sarcoglycan complex on muscle biopsy had a significant earlier onset of symptoms and an earlier age of loss of ambulation compared to patients with residual protein expression. This study confirmed that delta-sarcoglycanopathy is an ultra-rare neuromuscular condition and described the clinical and molecular characteristics of the largest yet-reported collected cohort of patients. Our results showed that this is a very severe and quickly progressive disease characterized by generalized muscle weakness affecting predominantly proximal and distal muscles of the limbs. Similar to other forms of sarcoglycanopathies, the severity and rate of progressive weakness correlates inversely with the abundance of protein on muscle biopsy. Alonso-Pérez et al. describe the largest cohort to date of patients with the ultra-rare neuromuscular disorder delta-sarcoglycanopathy, and show that the severity and rate of progressive weakness correlates inversely with the abundance of protein expression on muscle biopsy.

Sarcoglycanopathies comprise four subtypes of autosomal recessive limb-girdle muscular dystrophies (LGMDR3, LGMDR4, LGMDR5 and LGMDR6) that are caused, respectively, by mutations in the SGCA, SGCB, SGCG and SGCD genes. In 2016, several clinicians involved in the diagnosis, management and care of patients with LGMDR3–6 created a European Sarcoglycanopathy Consortium. The aim of the present study was to determine the clinical and genetic spectrum of a large cohort of patients with sarcoglycanopathy in Europe. This was an observational retrospective study. A total of 33 neuromuscular centres from 13 different European countries collected data of the genetically confirmed patients with sarcoglycanopathy followed-up at their centres. Demographic, genetic and clinical data were collected for this study. Data from 439 patients from 13 different countries were collected. Forty-three patients were not included in the analysis because of insufficient clinical information available. A total of 159 patients had a confirmed diagnosis of LGMDR3, 73 of LGMDR4, 157 of LGMDR5 and seven of LGMDR6. Patients with LGMDR3 had a later onset and slower progression of the disease. Cardiac involvement was most frequent in LGMDR4. Sixty per cent of LGMDR3 patients carried one of the following mutations, either in a homozygous or heterozygous state: c.229C>T, c.739G>A or c.850C>T. Similarly, the most common mutations in LMGDR5 patients were c.525delT or c.848G>A. In LGMDR4 patients the most frequent mutation was c.341C>T. We identified onset of symptoms before 10 years of age and residual protein expression lower than 30% as independent risk factors for losing ambulation before 18 years of age, in LGMDR3, LGMDR4 and LGMDR5 patients. This study reports clinical, genetic and protein data of a large European cohort of patients with sarcoglycanopathy. Improving our knowledge about these extremely rare autosomal recessive forms of LGMD was helped by a collaborative effort of neuromuscular centres across Europe. Our study provides important data on the genotype-phenotype correlation that is relevant for the design of natural history studies and upcoming interventional trials in sarcoglycanopathies.

In muscle ATP is primarily known for its function as an energy source and as a mediator of the “excitation-transcription” process, which guarantees muscle plasticity in response to environmental stimuli. When quickly released in massive concentrations in the extracellular space as in presence of muscle membrane damage, ATP acts as a damage-associated molecular pattern molecule (DAMP). In experimental murine models of muscular dystrophies characterized by membrane instability, blockade of eATP/P2X7 receptor (R) purinergic signaling delayed the progression of the dystrophic phenotype dampening the local inflammatory response and inducing Foxp3+ T Regulatory lymphocytes. These discoveries highlighted the relevance of ATP as a harbinger of immune-tissue damage in muscular genetic diseases. Given the interactions between the immune system and muscle regeneration, the comprehension of ATP/purinerigic pathway articulated organization in muscle cells has become of extreme interest. This review explores ATP release, metabolism, feedback control and cross-talk with members of muscle inflammasome in the context of muscular dystrophies.

The assessment of muscle fatigue could provide crucial information to monitor the progression of a neuromuscular disease, as well as evidences about the efficacy of an eventual therapeutic approach. The aim of the present work is to test the feasibility of a novel method based on a robotic wrist device and sEMG, on neuromuscular pediatric subjects for a future implementation in clinical practice. The proposed paradigm has been previously validated on a population of healthy subjects. Five children (age 8.8 ± 1.3 yo) with Duchenne Muscular Dystrophy (DMD) performed the test and their right flexor and extensor carpi radialis were recorded to obtain an objective indicator of muscle fatigue.

Background: Archaeological data provide evidence that Italy, during the Iron Age, witnessed the appearance of the first communities with well defined cultural identities. To date, only a few studies report genetic data about these populations and, in particular, the Piceni have never been analysed. Aims: To provide new data about mitochondrial DNA (mtDNA) variability of an Iron Age Italic population, to understand the contribution of the Piceni in shaping the modern Italian gene pool and to ascertain the kinship between some individuals buried in the same grave within the Novilara necropolis. Subjects and methods: In a first set of 10 individuals from Novilara, we performed deep sequencing of the HVS-I region of the mtDNA, combined with the genotyping of 22 SNPs in the coding region and the analysis of several autosomal markers. Results: The results show a low nucleotide diversity for the inhabitants of Novilara and highlight a genetic affinity of this ancient population with the current inhabitants of central Italy. No family relationship was observed between the individuals analysed here. Conclusions: This study provides a preliminary characterisation of the mtDNA variability of the Piceni of Novilara, as well as a kinship assessment of two peculiar burials.

In muscular dystrophies, muscle membrane fragility results in a tissue-specific increase of danger-associated molecular pattern molecules (DAMPs) and infiltration of inflammatory cells. The DAMP extracellular ATP (eATP) released by dying myofibers steadily activates muscle and immune purinergic receptors exerting dual negative effects: a direct damage linked to altered intracellular calcium homeostasis in muscle cells and an indirect toxicity through the triggering of the immune response and inhibition of regulatory T cells. Accordingly, pharmacologic and genetic inhibition of eATP signaling improves the phenotype in models of chronic inflammatory diseases. In α-sarcoglycanopathy, eATP effects may be further amplified because α-sarcoglycan extracellular domain binds eATP and displays an ecto-ATPase activity, thus controlling eATP concentration at the cell surface and attenuating the magnitude and/or the duration of eATP-induced signals. Herein, we show that in vivo blockade of the eATP/P2X purinergic pathway by a broad-spectrum P2X receptor-antagonist delayed the progression of the dystrophic phenotype in α-sarcoglycan-null mice. eATP blockade dampened the muscular inflammatory response and enhanced the recruitment of forkhead box protein P3-positive immunosuppressive regulatory CD4+ T cells. The improvement of the inflammatory features was associated with increased strength, reduced necrosis, and limited expression of profibrotic factors, suggesting that pharmacologic purinergic antagonism, altering the innate and adaptive immune component in muscle infiltrates, might provide a therapeutic approach to slow disease progression in α-sarcoglycanopathy.

Mutations in the guanosine diphosphate mannose (GDP-mannose) pyrophosphorylase B (GMPPB) gene encoding a key enzyme of the glycosylation pathway have been described in families with congenital (CMD) and limb girdle (LGMD) muscular dystrophy with reduced alpha-dystroglycan (α-DG) at muscle biopsy.Patients typically display a combined phenotype of muscular dystrophy, brain malformations, and generalized epilepsy. However, a wide spectrum of clinical severity has been described ranging from classical CMD presentation to children with mild, yet progressive LGMD with or without intellectual disability. Cardiac involvement, including a long QT interval and left ventricular dilatation, has also been described in four cases.Two missense mutations in GMPPB gene, one novel and one already reported, have been identified in a 21-year-old man presenting with elevated CK (38,650 UI/L; normal values150 UI/L) without overt muscle weakness. Major complaints included limb myalgia, exercise intolerance, and several episodes of myoglobinuria consistent with a form of metabolic myopathy. Muscle biopsy showed only minimal alterations, whereas a marked reduction of glycosylated α-DG was evident.This case further expands the phenotypic spectrum of GMPPB mutations and highlights the importance of exhaustive molecular characterization of patients with reduced glycosylation of α-DG at muscle biopsy.

Infiltration of immune cells and chronic inflammation substantially affect skeletal and cardiac muscle degeneration in Duchenne muscular dystrophy. In the immune system, extracellular adenosine triphosphate (ATP) released by dying cells is sensed as a danger associated molecular pattern through P2 purinergic receptors. Specifically, the P2X7 subtype has a prominent role in regulating immune system physiology and contributes to inflammasome activation also in muscle cells. Here, we show that in vivo blockade of the extracellular ATP/P2X purinergic signaling pathway by periodate-oxidized ATP delayed the progression of the dystrophic phenotype and dampened the local inflammatory response in mdx mice, a spontaneous mouse model of dystrophin deficiency. Reduced infiltration of leukocytes and macrophages and decreased expression of IL-6 were revealed in the muscles of periodate-oxidized ATP-treated mdx mice. Concomitantly, an increase in Foxp3(+) immunosuppressive regulatory T cells was observed and correlated with enhanced myofiber regeneration. Moreover, we detected reduced concentrations of profibrotic cytokines, including transforming growth factor-β and connective tissue growth factor, in muscles of periodate-oxidized ATP-treated mdx mice. The improvement of inflammatory features was associated with increased strength and reduced necrosis, thus suggesting that pharmacologic purinergic antagonism altering the adaptive immune component in the muscle infiltrates might represent a promising therapeutic approach in Duchenne muscular dystrophy.

Ofatumumab is an anti‐CD20 humanized monoclonal antibody utilized in the treatment of several clinical conditions resistant to other treatments. In spite there was a general expectation that ofatumumab was less toxic compared to rituximab, side effects have been reported that resemble those of its anti‐CD20 chimeric precursor. Here, we describe the first case of Ofatumumab associate lung injury occurring in a 14‐year‐old boy affected by nephrotic syndrome dependent to prednisone plus cyclosporine A who had been treated with the dose of drug utilized in nephrotic syndrome (1500 mg/173 m2). The patient developed the full blown picture of rituximab associated lung injury (RALI) after 45 days from ofatumumab infusion at the end of the steroid tapering: severe exertional dyspnea, mild fever and cyanosis, with CT scan showing diffuse ground glass areas in both lungs and DLCO (diffusing capacity of transfer factor of the lung for carbon monoxide) test suggestive for reduction of CO diffusion. Clinical outcome was good with rapid improvement and normalization of all parameters without any specific therapy. After 60 days, chest CT and CO diffusion tests were normal. In conclusion, we describe here the first case of acute pneumonitis associated with ofatumumab that presents the same clinical, laboratory, and radiology features of the lung injury reported for rituximab. Like RALI occurring in patients treated for nephrotic syndrome, this case had a mild clinical expression and recovered in a few months.