Journal of Clinical Neuromuscular Disease最新文献

Abstract: The review begins with epidemiology studies that show an increased incidence of later onset myasthenia gravis (MG) and higher short-term mortality rates, especially in females, compared with the general population in Denmark. In the United States, a study showed increased mortality especially in older patients, and there was racial disparity. In France, a study showed higher mortality with male gender, older age, and higher comorbidities. Economic burden is addressed in another article. Regarding clinical features, light sensitivity in MG is discussed along with differentiating thyroid eye disease symptoms and signs from those of ocular MG. MG-specific measures are highlighted with consensus recommendations for their use. Several articles contain data regarding diagnostic laboratory assays and test sensitivity and specificity among other measures. The role of thymectomy in older patients with MG is considered. The medical treatment section addresses corticosteroid regimens, intravenous immunoglobulin as maintenance therapy, a phase 3 study of the recently approved neonatal Fc receptor (FcRN) blocker nipocalimab, use of complement inhibitors and FcRN blockers in general, regimens for efgartigimod, and positive studies on the interleukin-16 receptor monoclonal antibody (Ab) satralizumab and the CD19 B-cell-depleting monoclonal Ab inebilizumab.

Objectives: Synaptotagmin-2-related disease is an ultrarare entity, characterized by distal muscle atrophy in the lower limbs, foot deformities and, in some cases, neonatal hypotonia. Most mutations are concentrated in the C2B domain, critical for the protein's function. Here, our objective is to review clinical, electrophisiological and pathological aspects of this disease.

Methods: We describe a previously unreported variant, comparing it with another 27 cases described in the literature.

Results: A 14-year-old boy was born with neonatal hypotonia, weak cry, and dysphonia. During childhood, he had recurrent respiratory infections, delayed motor development, and developed glaucoma. Creatine phosphokinase level was 501 U/L; EMG showed reduced compound muscle action potential, myopathic findings, and incremental response. A comprehensive next-generation sequence panel revealed a homozygous variant in the SYT2 gene.

Conclusions: The data summarized here and our case provide a general characterization of the phenotypic spectrum of SYT2-related disease and point out to its electrophysiological and pathological features. We discuss the intriguing aspects of a neuromuscular junction disease considered as a distal hereditary motor neuropathy.

Abstract: To describe a 51-year-old woman with early-onset weakness and foot deformities carrying a biallelic truncating mutation in the VWA1 gene. The patient underwent laboratory tests, nerve conduction studies with electromyography, muscle magnetic resonance imaging, muscle biopsy, and genetic testing. Neurophysiological studies and biopsy revealed both myopathic and neuropathic features. Muscle magnetic resonance imaging showed a distinctive outside-in pattern of fatty replacement in the vastus lateralis, resembling that seen in type VI collagen-related myopathies. Whole-exome sequencing identified a homozygous pathogenic variant in VWA1, which encodes an extracellular matrix protein found in the basement membranes of nerves and muscles. Recently, truncating mutations in VWA1 have been associated with previously unsolved neuromyopathy cases. In one of these reports, as in the current case, the MRI pattern mimicked that of type VI collagen disorders. Biallelic VWA1 mutations may account for some genetically undiagnosed cases of neuropathy with myopathic features.

Objectives: Nitrous oxide is a multipurpose gas that has recently gained attention because of its use as a recreational drug and the associated neurological complications of abuse.

Methods: Seven patients were included, and clinical, electrodiagnostic, imaging, and serological data were retrospectively analyzed.

Results: All patients presented with various degrees of sensory impairment, gait disorder, muscle weakness, or ataxia, mainly involving the lower limbs. Electrodiagnostic studies showed a predominantly motor neuropathy, with axonal, demyelinating, or mixed features. Spinal magnetic resonance imaging showed posterior cord lesions in cervical regions, with 2 patients presenting concomitant thoracic cord lesions. Homocysteine levels were elevated in all patients.

Conclusions: Nitrous oxide abuse is known to be connected to the development of both polyneuropathy and myelopathy. Better understanding of the physiological, clinical, and paraclinical aspects of this pathology is needed to make a correct differential diagnosis and conduct and adequate treatment.