Journal of Clinical Neuromuscular Disease

This update covers several articles on diagnosis and misdiagnosis of myasthenia gravis (MG), the role of complement in MG, and then an impressive number of recent treatment trials. There is a negative study on any corticosteroid-sparing effect of intravenous immunoglobulin. A number of positive studies are reviewed. Open-label extension studies of phase 3 trials showed benefit regarding quality of life with efgartigimod and in functional measures with ravulizumab. The phase 3 RAISE trial of zilucoplan, a self-administered complement C5 inhibitor, is covered as well as the MyCarinG trial of rozanolixizumab...

OBJECTIVES: Isaac syndrome (IS) is a condition characterized by peripheral nerve hyperexcitability caused by voltage-gated potassium channel (VGKC)-complex antibodies. Muscle twitching, stiffness, hypertrophy, and dysautonomic characteristics, such as hyperhidrosis, are common manifestations. The syndrome can be autoimmune or paraneoplastic, with thymoma being a common cause of paraneoplastic IS. Furthermore, this condition could be handed down from one generation to another. However, there is limited information regarding outcomes, relapses, associated syndromes, associated malignancies (other than thymoma), and treatment options...

Immune checkpoint inhibitors used to treat malignancies may lead to various immune-related adverse events (irAEs) including conditions such as myositis and myasthenia gravis (MG). Here, we describe 2 cases of myositis treated effectively with therapeutic plasma exchange (PLEX). A 64-year-old man with thymic cancer developed leg weakness and dyspnea 1 month after the second dose of nivolumab with moderate weakness in proximal and distal muscles, with elevated creatine kinase levels. Another 77-year-old man with Stage IIIB squamous cell carcinoma of the lung developed progressive proximal muscle weakness and became nonambulatory after cycle 2 of durvalumab with persistently high creatine kinase levels despite prednisone treatment...

INTRODUCTION: The course of double-seronegative myasthenia gravis (DSNMG) during and after pregnancy has not been well described. OBJECTIVE: To assess the course of DSNMG during pregnancy and within 6 months postpartum. METHODS: A retrospective cohort study of women with DSNMG seen in the Duke Myasthenia gravis (MG) Clinic after 2003. RESULTS: Review of the Duke MG Clinic Registry and electronic medical record identified 8 patients who became pregnant after MG onset; the mean age at disease onset was 17...

Isaac syndrome is one of the rare peripheral nerve hyperexcitability (PNH) syndromes, which manifests with gross fasciculations, muscle undulation, twitching, and cramps, with or without autonomic and sensory symptoms. The diagnosis relies on characteristic electromyogram findings and the presence of anti-leucine-rich glial inactivated 1 and anti-contactin-associated protein 2 antibodies in the serum. Here, we report the case of a 21-year-old woman, who presented with extremities and tongue myokymia whose electromyogram findings were compatible with PNH, albeit seronegative for antibodies...

OBJECTIVES: As the clinical course of autosomal recessive limb-girdle muscular dystrophy (LGMDR) is highly variable, this study characterized the frequency of loss of ambulation (LOA) among patients by subtype (LGMDR1, LGMDR2, LGMDR3-6, LGMDR9, LGMDR12) and progression to cardiac and respiratory involvement among those with and without LOA. METHODS: Systematic literature review. RESULTS: From 2929 abstracts screened, 418 patients were identified with ambulatory status data (LOA: 265 [63...

No abstract text is available yet for this article.

OBJECTIVES: Anti-neurofascin-155 IgG4 (NF-155) antibody disease has previously been associated with a subset of patients with chronic inflammatory demyelinating polyradiculoneuropathy. We report a case of NF-155 positive polyneuropathy that initially presented as an acute inflammatory demyelinating polyradiculoneuropathy. The patient responded appropriately to treatment but subsequently progressed over a 3-month period, resulting in quadriplegia, areflexia, and oculobulbar paralysis. METHODS: Case report and literature review...

No abstract text is available yet for this article.

No abstract text is available yet for this article.

No abstract text is available yet for this article.

Congenital myasthenic syndromes (CMS) are relatively rare neurologic syndromes of defective neuromuscular transmission that stem from mutations in various proteins at the myoneural junction. Classically, the patients present within the first 2 years of life; however, the disease can also have onset in the second or third decade of life. The disease characteristically involves the skeletal muscles and spares smooth and cardiac muscles. The patients present with weakness involving ocular, limb, axial, or bulbar muscles...

We report a 5-year-old boy who presented with progressive weakness in 4 limbs and gait disorders over 7 months. No skin rash was observed on admission. A symmetrical proximodistal weakness was found. The creatine kinase level was normal with a slightly elevated lactate dehydrogenase level. Biopsy specimens showed infiltration of mononuclear cells, few necrotic fibers, and perifascicular atrophy. Screening for myositis-specific antibodies was positive for the antinuclear matrix protein 2 antibody, which is mainly associated with dermatomyositis...

Tangier disease is an autosomal recessive multisystem metabolic disorder with neuromuscular manifestations including peripheral neuropathy such as multifocal mononeuropathy or pseudosyringomyelia patterns. We report a novel phenotype of Tangier disease with predominant anterior horn cell involvement. A 16-year-old adolescent girl born to consanguineous parents had a 1-year history of hip girdle weakness with waddling gait and progressive atrophy of the right leg. She had orange tonsils, prominent lingual tonsils, soft skin, distal joint laxity, diffuse hypotonia with asymmetric wasting of legs, proximodistal moderate weakness in lower limbs, and tendon reflexes were hypoactive...

OBJECTIVES: Periodic paralysis is a rare genetic condition characterized by episodes of neuromuscular weakness, often provoked by electrolyte abnormalities, physiologic stress, physical exertion, and diet. In addition to mutations in genes coding for skeletal muscle ion channels, in 2019, Gustavasson et al discovered that the MCM3AP gene could be responsible for periodic paralysis. In this study, we present 2 individuals with clinical episodes of periodic paralysis who have variants in the MCM3AP gene...

INTRODUCTION: Peripheral nerve injuries are being increasingly recognized in patients recovering from severe SARS-CoV-2 infections. Axonal neuropathies can occur, leading to lasting and disabling deficits. CASE REPORTS: We present the cases of 3 patients who developed weakness and sensory symptoms after severe SARS-CoV-2 pneumonia. The clinical deficits revealed various patterns of injury including a mononeuropathy multiplex (MNM) in the first patient, a brachial plexopathy with superimposed MNM in the second patient, and a mononeuropathy superimposed on a polyneuropathy in the third patient...

ABSTRACT: Myasthenia gravis (MG) is an autoimmune disease of multifactorial etiology in which genetic factors and cytokines seem to play an important role. The aim of this study was to investigate potential associations of cytokines single nucleotide polymorphisms (SNPs) and MG in Algerian patients. We performed a case-control study that included 27 patients and 74 healthy subjects. Cytokines SNPs genotyping was performed by the polymerase chain reaction sequence-specific primers (PCR-SSP) method...

OBJECTIVES: Plasmapheresis (PLEX) and intravenous immunoglobulin (IVIg) are commonly used to treat autoimmune neuromuscular disorders, including myasthenia gravis, acute inflammatory demyelinating polyradiculoneuropathy, chronic inflammatory demyelinating polyradiculoneuropathy, and other autoimmune neurological disorders. The side effect profiles of these therapies vary, and concern has been raised regarding the safety of PLEX in the elderly population. In this study, we have examined the pattern of PLEX and IVIg use for autoimmune neurological disorders at a single facility and in a national database, focusing on the complications in elderly patients...

In the context of the global vaccination campaign against COVID-19, several cases of postvaccinal Guillain-Barré syndrome (GBS) were reported. Whether a causal relationship exists between these events has yet to be established. We investigated the clinical and electromyographic characteristics of patients who developed GBS after COVID-19 vaccination and compare these with findings in patients with GBS, without a history of recent vaccination. We included 91 cases between March 2020 and March 2022, treated at 10 referral hospitals of Buenos Aires, Argentina...

OBJECTIVES: To evaluate patient attitudes and beliefs toward thymectomy for myasthenia gravis (MG). METHODS: The Myasthenia Gravis Foundation of America administered a questionnaire to the MG Patient Registry, an ongoing longitudinal survey of adult MG patients. Questions assessed reasons for or against thymectomy and how hypothetical scenarios would have affected their decision. RESULTS: Of 621 respondents, 190 (31%) reported a history of thymectomy...