Myasthenia gravis associated with anti-MuSK antibodies developed after SARS-CoV-2 infection

Clinical features of COVID-19 infection in patients with myasthenia gravis: a real-world retrospective study

Objective

We investigated the risk factors associated with severe or critical Coronavirus disease 2019 (COVID-19) infection due to the Omicron variant in patients with myasthenia gravis (MG) and determined the potential effect of COVID-19 on myasthenic exacerbation during the Omicron pandemic.

Methods

This retrospective study included 287 patients with MG in Tianjin, China. Clinical data of the patients were collected using electronic questionnaires, databases, and clinical records.

Results

The overall infection rate was 84.7%. Advanced age, comorbidities, generalized phenotype, and MG instability were drivers of COVID-19 severity, and post-COVID-19 myasthenic exacerbation. The concurrent use of a steroid-sparing agent did not affect COVID-19 susceptibility or severity. It did lower the risk of myasthenic exacerbation after COVID-19 infection. Patients with severe COVID-19 experienced myasthenic exacerbation earlier than patients with non-severe infection (p < 0.001). The severity of COVID-19 (Hazards Ratio = 3.04, 95% CI: 1.41-6.54, p = 0.004) and the clinical phenotype (Hazards Ratio = 3.29, 95% CI: 1.63-6.63, p < 0.001) emerged as independent risk factors for early MG exacerbation.

Conclusion

Generally, patients with MG appear to be susceptible to the Omicron strains. Immunotherapy for MG did not increase COVID-19 susceptibility or severity. We do not advocate an immediate cessation of ongoing immunosuppressive treatments once a COVID-19 infection is diagnosed. Instead, a judicious evaluation of the risks and benefits, tailored to each individual, is recommended.

Seronegative Myasthenia Gravis: A Rare Disease Triggered by SARS-CoV-2 or a Coincidence?

Myasthenia gravis (MG) results from the production of autoantibodies against the neuromuscular junction, leading to muscle weakness. Although the exact cause is not fully understood, it is known that the onset and exacerbations of MG can occur after viral infections. We present the case of a patient with no prior history of MG with new-onset proximal muscle weakness and ptosis, following SARS-CoV-2 infection, This case underscores the potential for autoimmune diseases to be triggered by SARS-CoV-2.

A Bead-Based Nonradioactive Immunoassay for Autoantibody Testing in a Mouse Model of Myasthenia Gravis

Serological testing for anti-acetylcholine receptor (AChR) autoantibodies is not only crucial for the diagnosing, disease monitoring, and treatment management of patients with myasthenia gravis (MG) but also for preclinical studies utilizing MG disease models. However, there are no specific guidelines on which methods to use in clinical diagnostic or research laboratories to detect or quantify any MG-specific autoantibodies. Conventional autoantibody assays, particularly those for anti-AChR antibodies, are varied and mostly laboratory-specific. Here, we report our new nonradioactive immunoprecipitation-immunoblotting method for assessing autoantibodies (anti-AChR antibodies) in a mouse model of MG. This simple, efficient, reproducible, and cost-effective assay appears superior to the enzyme-linked immunosorbent assay but comparable to the radioimmunoprecipitation or cell-based assay in specificity and sensitivity. Thus, the newly developed assay can serve as a valuable alternative to classical assays and is suitable for routine testing of AChR-specific autoantibodies in preclinical studies. The further optimization of our assay may facilitate its application in the diagnosis and therapeutic management of patients with MG.

The Neurological Implications of COVID-19: A Comprehensive Narrative Review

The COVID-19 pandemic caused by the coronavirus SARS-CoV-2 revealed a huge number of problems as well as discoveries in medicine, notably, regarding the effects of the virus on the central nervous system (CNS) and peripheral nervous system (PNS). This paper is a narrative review that takes a deep dive into the complex interactions between COVID-19 and the NS. Therefore, this paper explains the broad range of neurological manifestations and neurodegenerative diseases caused by the virus. It carefully considers the routes through which SARS-CoV-2 reaches the NS, including the olfactory system and of course, the hematogenous route, which are also covered when discussing the virus's direct and indirect mechanisms of neuropathogenesis. Besides neurological pathologies such as stroke, encephalitis, Guillain-Barré syndrome, Parkinson's disease, and multiple sclerosis, the focus area is also given to the challenges of making diagnosis, treatment, and management of these conditions during the pandemic. The review also examines the strategic and interventional approaches utilized to prevent these disorders, as well as the ACE2 receptors implicated in the mediation of neurological effects caused by COVID-19. This detailed overview, which combines research outputs with case data, is directed at tackling this pandemic challenge, with a view toward better patient care and outcomes in the future.

Myasthenia Gravis Triggered by a COVID-19 Infection: A Case Report and Literature Review

Myasthenia gravis (MG) is an autoimmune disease that induces skeletal muscle weakness, affecting different muscle groups. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of coronavirus disease 2019 (COVID-19), became both a diagnostic and a therapeutic challenge during the pandemic. The effects of COVID-19 are not only limited to the acute symptoms but also to the post-infectious sequelae. We present the case of a 30-year-old Caucasian woman, with no significant medical history, who presented to the emergency room with acute respiratory failure. The patient tested positive for SARS-CoV-2 with a rapid antigen test and during hospitalization developed a myasthenic crisis, ultimately being diagnosed with seropositive MG.

Identification of key genes as potential diagnostic and therapeutic targets for comorbidity of myasthenia gravis and COVID-19

Introduction

Myasthenia gravis (MG) is a chronic autoimmune neuromuscular disorder. Coronavirus disease 2019 (COVID-19) has a significant impact on the health and quality of life of MG patients and may even trigger the onset of MG in some cases. With the worldwide development of the COVID-19 vaccination, several new-onset MG cases and exacerbations following the COVID-19 vaccines have been acknowledged. The potential link between myasthenia gravis (MG) and COVID-19 has prompted the need for further investigation into the underlying molecular mechanism.

Methods and results

The differential expression analysis identified six differentially expressed genes (DEGs) shared by myasthenia gravis (MG) and COVID-19, namely SAMD9, PLEK, GZMB, JUNB, NR4A1, and NR1D1. The relationship between the six common genes and immune cells was investigated in the COVID-19 dataset. The predictive value of the shared genes was assessed and a nomogram was constructed using machine learning algorithms. The regulatory miRNAs, transcription factors and small molecular drugs were predicted, and the molecular docking was carried out by AutoDock.

Discussion

We have identified six common DEGs of MG and COVID-19 and explored their immunological effects and regulatory mechanisms. The result may provide new insights for further mechanism research.

Association between COVID-19 and myasthenia gravis (MG): A genetic correlation and Mendelian randomization study

BACKGROUND

Observational studies have suggested an association between coronavirus disease 2019 (COVID-19) and myasthenia gravis (MG). Here, we aimed to estimate the genetic correlation and causal relationship between COVID-19 susceptibility, hospitalization, severity, and MG phenotypes using linkage disequilibrium score regression (LDSC) and Mendelian randomization (MR) approach.

METHODS

Summary statistics of COVID-19 susceptibility, hospitalization, and severity were used as instrumental variables for exposure traits. Large-scale genome-wide association study (GWAS) data for MG were used as outcome traits. The inverse variance weighted approach was used for the main MR analysis, complemented by MR-Egger, weighted median, simple mode, and weighted mode methods. Sensitivity analysis was implemented using Cochran's Q test, MR-PRESSO method, and MR-Egger intercept test.

RESULTS

LDSC analysis did not reveal any genetic correlation among COVID-19 susceptibility, hospitalization, severity, and MG phenotypes, including MG, early-onset MG, and late-onset MG (p > .05). Our MR analysis did not provide evidence supporting a causal effect of COVID-19 susceptibility, hospitalization, or severity on MG phenotypes (p > .05). Extensive sensitivity analysis strengthened the robustness and consistency of the MR estimates.

CONCLUSION

Our study did not find evidence of a genetic correlation or causal relationship among COVID-19 susceptibility, hospitalization, severity, and MG. Future studies with more GWAS data are needed to evaluate the association between COVID-19 phenotypes and MG and its subgroups.

COVID-19: a modern trigger for Guillain-Barre syndrome, myasthenia gravis, and small fiber neuropathy

COVID-19 infection has had a profound impact on society. During the initial phase of the pandemic, there were several suggestions that COVID-19 may lead to acute and protracted neurologic sequelae. For example, peripheral neuropathies exhibited distinctive features as compared to those observed in critical care illness. The peripheral nervous system, lacking the protection afforded by the blood-brain barrier, has been a particular site of sequelae and complications subsequent to COVID-19 infection, including Guillain-Barre syndrome, myasthenia gravis, and small fiber neuropathy. We will discuss these disorders in terms of their clinical manifestations, diagnosis, and treatment as well as the pathophysiology in relation to COVID-19.

Autoimmune myasthenia gravis and COVID-19. A case report-based review

A potential relationship between COVID-19 infection and new onset myasthenia gravis (MG) has been suggested by the coexistence of these two diseases in a number of reports. This study aimed to assess their relationship by reviewing case studies of COVID-19 followed by new onset MG published between 01 December 2019 and 30 June 2023 identified by a search of PubMed/Medline database. In addition, we reviewed evidence in favour and against a potential cause and effect association, and described possible mechanisms that would underpin such a relationship. We identified 14 publications that reported 18 cases. Analysis showed the following features: age 19-83 years; 10 men/8 women; median time interval between COVID-19 and MG (17, 5-56 days); autoimmune comorbidities (4); generalised MG (14); ocular MG (4); thymoma (3); antiacetylcholine receptor antibody (16); antimuscle-specific kinase antibodies (2). All patients improved following treatment. Proof of direct causality between the two conditions can only be established in time by confirming epidemiological increase in the incidence of MG or elucidating pathogenic mechanisms to substantiate a possible cause-effect association, or both.

Neurologic and Neuromuscular Sequelae of COVID-19

It is known that there can be neurologic complications related to acute infection with SARS-CoV-2, the virus that causes COVID-19. Currently, there is a growing body of evidence that postacute sequelae of SARS-CoV-2 infection can manifest as neurologic sequelae as a result of direct neuroinvasion, autoimmunity, and possibly lead to chronic neurodegenerative processes. Certain complications can be associated with worse prognosis, lower functional outcome, and higher mortality. This article provides an overview of the known pathophysiology, symptoms presentation, complications and treatment approaches of the post-acute neurologic and neuromuscular sequelae of SARS-CoV-2 infection.

Neurological manifestations of COVID-19: a systematic review and detailed comprehension

The current pandemic caused by severe acute respiratory syndrome corona virus 2 (SARS-CoV-2) is accompanied with a rapid increase of reports and papers detailing its neurological effects and symptoms. The virus infection causes respiratory illness named by the world health organization as corona virus 19 (COVID-19).This systematic review aims to study and summarize the different neurological manifestations of this virus. All articles published and indexed via Pubmed, Medline and Google Scholar databases between January 1st 2020 and February 28th 2021 that reported neurological symptoms of SARS-CoV-2 are reviewed following the Preferred Reporting Items for Systemic review and Meta-Analysis (PRISMA) guidelines.We included data from 113 articles: eight prospective studies, 25 retrospective studies and the rest were case reports/series. COVID-19 can present with central nervous system manifestations, such as headache, encephalitis and encephalopathy, peripheral nervous system manifestations, such as anosmia, ageusia and Guillian Barre syndrome, and skeletal muscle manifestations, such as myalgia and myasthenia gravis. Our systematic review showed that COVID-19 can be manifested by a wide spectrum of neurological symptoms reported either in the early stage or within the course of the disease. However, a detailed comprehension of these manifestations is required and more studies are needed in order to improve our scientific knowledge and to develop preventive and therapeutic measures to control this pandemic.

Myasthenia Gravis Associated With COVID-19 Infection

COVID-19 first emerged in Wuhan, China in late December 2019. The disease majorly involves the lungs leading to various respiratory complications; however, neurological manifestations of the disease are also described in the literature. Here, we report a case of COVID-19-induced seronegative myasthenia gravis (MG). We discuss the cases of COVID-19 and MG already described in the literature in regard to their presentation and serological findings to better understand the association between the two disease processes. MG may be missed in patients after COVID-19 infections because of the comorbidities and anti-acetylcholine receptor and anti-muscle-specific tyrosine kinase antibodies being negative. Evidence from more studies will help analyze the pathological timeline of the disease process and the immunological characteristics of COVID-19-induced MG which can prove to have morbidity and mortality benefit in patients with COVID-19-induced MG.

Epitranscriptomic N6-Methyladenosine Profile of SARS-CoV-2-Infected Human Lung Epithelial Cells

N6-methyladenosine (m6A) is a dynamic posttranscriptional RNA modification that plays an important role in determining transcript fate. The functional consequence of m6A deposition is dictated by a group of host proteins that specifically recognize and bind the m6A modification, leading to changes in RNA stability, transport, splicing, or translation. The cellular m6A methylome undergoes changes during certain pathogenic conditions such as viral infections. However, how m6A modification of host cell transcripts and noncoding RNAs change during severe acute respiratory syndrome coronavirus (SARS-CoV-2) infection has not been reported. Here, we define the epitranscriptomic m6A profile of SARS-CoV-2-infected human lung epithelial cells compared to uninfected controls. We identified mRNA and long and small noncoding RNA species that are differentially m6A modified in response to SARS-CoV-2 infection. The most significantly differentially methylated transcript was the precursor of microRNA-4486 (miRNA-4486), which showed significant increases in abundance and percentage of methylated transcripts in infected cells. Pathway analyses revealed that differentially methylated transcripts were significantly associated with several cancer-related pathways, protein processing in the endoplasmic reticulum, cell death, and proliferation. Upstream regulators predicted to be associated with the proteins encoded by differentially methylated mRNAs include several proteins involved in the type-I interferon response, inflammation, and cytokine signaling. IMPORTANCE Posttranscriptional modification of viral and cellular RNA by N6-methyladenosine (m6A) plays an important role in regulating the replication of many viruses and the cellular immune response to infection. We therefore sought to define the epitranscriptomic m6A profile of human lung epithelial cells infected with SARS-CoV-2. Our analyses demonstrate the differential methylation of both coding and noncoding cellular RNAs in SARS-CoV-2-infected cells compared to uninfected controls. Pathway analyses revealed that several of these RNAs may be involved in the cellular response to infection, such as type-I interferon. Our study implicates m6A modification of infected-cell RNA as a mechanism of posttranscriptional gene regulation during SARS-CoV-2 infection.

Clinical course and outcome of Covid-19 in patients with myasthenia gravis

OBJECTIVES

To analyze the prognosis and outcomes of COVID-19 in patients with MG and to determine factors associated with COVID-19 severity in patients with MG.

METHODS

Information concerning COVID-19 occurrence in patients with MG was collected in this single-center observational study. Univariate and multivariate analyses were used to identify factors associated with severe Covid-19.

RESULTS

Two hundred seventy-five of the 386 records of MG were included in this study. Eighty-two (29.8%) patients had concurrent COVID-19 . The patients' mean age was 50.3 ± 1.6 years, and the mean duration of MG was 6.7 ± 5.4 years. MG was diagnosed after COVID-19 in five cases. Covid-19 was mild in 45 patients (54.9%), moderate in 23 (28.1%), and severe in 14 (17.07%), while mortality occurred in four of the severe cases (4.9%). Three of the exitus patients were receiving rituximab therapy. Pre-Covid MG Activity of Daily Living (MG-ADL) severity scores were significantly high in severe cases. A history of myasthenic crisis was also higher in severe cases. Similarly, univariate and multivariate analyses revealed an association between severe COVID-19 and myasthenic crisis history and high pre-Covid MG-ADL. The type of MG treatment had no independent effect on COVID-19 severity.

CONCLUSION

The vast majority of the MG patients made a good recovery from Covid-19. The risk of severe COVID-19 is high in patients with high MG-ADL severity scores and a history of myasthenic crisis.

New-onset Myasthenia Gravis after SARS-CoV-2 infection: case report and literature review

We report the case of a 19-year-old female patient who developed Myasthenia Gravis 13 days after SARS-CoV-2 infection with positive RT-PCR testing. Her symptoms initially involved the oculo-bulbar district, but they gradually worsened in 3 months converting into a generalized form of Myasthenia Gravis complicated with a myasthenic crisis. A high level of anti-acetylcholine receptor antibodies was found in the serum, while anti-MuSK antibodies were negative; Repetitive Nerve Stimulation and Single-fiber Electromyography were suggestive of Myasthenia Gravis. Intravenous immunoglobulin courses and specific therapy were able to improve her symptoms, but thymic resection was needed to control the disease. This is a report of new-onset Myasthenia Gravis correlated to COVID-19 in which thymic resection was described and the histologic analysis of the thymus was performed showing thymic hyperplasia despite negative thoracic Magnetic Resonance Imaging. SARS-CoV-2 infection releases inflammatory cytokines that could dysregulate the immune system and lead to Myasthenia Gravis in susceptible subjects.

A Case Report and Literature Review of New-Onset Myasthenia Gravis After COVID-19 Infection

Myasthenia gravis (MG) is an autoimmune disorder affecting the neuromuscular junction caused by a B-cell-mediated, T-cell-dependent immunologic attack at the end plate of the postsynaptic membrane. Attack on muscle acetylcholine receptors (AChR) of the postsynaptic membrane due to the AChR, muscle-specific tyrosine kinase, or lipoprotein receptor-related peptide 4 antibodies lead to symptoms of painless, fluctuating weakness of muscle groups and often begins with ocular signs and symptoms. Coronavirus disease 2019 (COVID-19) is an acute respiratory disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel coronavirus closely related to SARS-CoV. Serious neurologic complications are infrequent and diverse with reported cases of stroke, encephalitis/meningitis, Guillain-Barré syndrome, acute disseminated encephalomyelitis, ataxia, and unspecified limb weakness. MG is a rarely reported sequela of COVID-19 infection. To date, there are 15 reported cases of post-COVID-19 MG. In this article, we present a case of post-COVID-19 MG and a concise review of other reported cases. An 83-year-old Caucasian male with a medical history of atrial fibrillation status post-ablation and non-ischemic cardiomyopathy was initially admitted for COVID-19 pneumonia. He was treated with remdesivir, convalescent plasma, and supplemental oxygen therapy but did not require invasive mechanical intubation. One month after discharge, he started experiencing fatigue with muscle weakness and progressive dyspnea. He progressed to develop dysphonia, especially at the end of the day. After extensive workup, he was diagnosed with MG with a positive antibody against the AChR. The chronological events of developing slowly worsening muscular weakness after recovering from COVID-19 infection and positive AChR antibody led to the diagnosis of post-COVID-19 new-onset MG. Post-COVID-19 fatigue, long-term use of steroids, and intensive care unit-related physical deconditioning can be confounders in the clinical presentation of post-COVID-19 new-onset MG. Careful history-taking and meticulous assessment of chronological events are needed to diagnose this rare entity.

COVID-19 and myasthenia gravis: A review of neurological implications of the SARS-COV-2

INTRODUCTION

This review highlights the potential mechanisms of neuromuscular manifestation of COVID-19, especially myasthenia gravis (MG).

METHODS

An extensive literature search was conducted by two independent investigators using PubMed/MEDLINE and Google Scholar from its inception to December 2020.

RESULTS

Exacerbations of clinical symptoms in patients of MG who were treated with some commonly used COVID-19 drugs has been reported, with updated recommendations of management of symptoms of neuromuscular disorders. Severe acute respiratory syndrome coronavirus 2 can induce the immune response to trigger autoimmune neurological disorders.

CONCLUSIONS

Further clinical studies are warranted to indicate and rather confirm if MG in the setting of COVID-19 can pre-existent subclinically or develop as a new-onset disease.

The relationship between myasthenia gravis and COVID-19: a systematic review

Introduction

Viral infection such as coronavirus disease 2019 (COVID-19) can exacerbate and aggravate neurological disorders due to autoimmune etiology like myasthenia gravis (MG). Experimental therapies used in COVID-19 are also factors that can cause the worsening of MG symptoms. This review aimed to assess and conclude the research-based study systematically to analyze the relationship of MG and COVID-19.

Method

This study was conducted in accordance to Cochrane handbook for systematic reviews and the guideline of preferred reporting items for systematic review and meta-analysis (PRISMA) and synthesis without meta-analysis (SWiM) in systematic reviews: reporting guideline. Inclusion criteria in this review were primary studies of every design, articles published in English around January 2000–October 2021, and the study used human as subject. A systematic literature finding was applied in 15 electronic scientific resources. The authors evaluated the study quality and risk of bias of each retrieved article.

Results

The authors found the study through electronic scientific resources that met inclusion and exclusion criteria. The authors evaluated 362 articles identified in literature searching, 22 articles met the criteria for this review and then underwent the evaluation of study quality and risk of bias.

Conclusion

COVID-19 infection can increase the risk of new-onset MG, myasthenic crisis, respiratory failure, and mortality rate due to cytokine storm in MG patients. The management of COVID-19 patients with MG is tailored to each person and based on national guidelines and local expert recommendations.

Efferent neuro-ophthalmic complications of coronavirus disease 2019

PURPOSE OF REVIEW

We set out to describe efferent neuro-ophthalmological complications that have been reported in association with coronavirus disease 2019 (COVID-19) infection. We describe syndromes affecting ocular motility and elaborate on mechanisms of disease, including para-infectious inflammation, hypercoagulability, endothelial damage, and direct neurotropic viral invasion. Despite global vaccination programs, COVID-19 continues to pose an international threat that may rarely result in diplopia or nystagmus.

RECENT FINDINGS

Efferent complications include cranial nerve palsies leading to diplopia, either isolated or in association with Miller Fisher syndrome. Nystagmus has been observed in the setting of hemorrhagic acute necrotizing encephalopathy and brainstem infarcts, and opsoclonus syndrome has been described.

SUMMARY

Observed neuro-ophthalmic associations need to be confirmed through larger comparative studies. Meanwhile, the range of possible complications should be recognized by neurologists and ophthalmologists alike, to facilitate faster diagnosis and treatment of both COVID-19 and its neuro-ophthalmic manifestations.

Autoimmune myasthenia gravis after COVID-19 in a triple vaccinated patient

Despite a well characterized mechanism, myasthenia gravis (MG) remains a dilemma in terms of etiology. Several case reports and series of cases suggest a potential cause-effect relation between SARS-CoV-2 infection or vaccination and MG. We present the case of an autoimmune MG occurring post Covid-19 in an elderly male, vaccinated with three doses of the BNT162b2/Pfizer-BioNTech vaccine. The 78-year-old male was admitted in the Neurology Clinic in early November 2021 with double vision, bilateral ptosis, dysphonia and dysphagia, 16 days after receiving a third dose of the BNT162b2/Pfizer-BioNTech SARS-CoV-2 vaccine and 12 days after testing positive for SARS-CoV-2 infection. The symptoms began to emerge at 9 days after COVID-19 diagnosis. Clinical neurological examination included ice-pack test and intramuscular neostigmine, both with positive results. Myasthenia gravis positive diagnosis was confirmed by slow repetitive nerve stimulation and abnormally increased serum levels of antibodies against acetylcholine receptors. Due to patient's refusal of further hospitalization, he was discharged with therapy recommendations. Under treatment with oral pyridostigmine, but no oral corticosteroid due to therapeutic noncompliance, the patient was readmitted two months later with aggravated symptoms. The myasthenic crisis was successfully treated with intravenous immunoglobulins, corticosteroid therapy and oral pyridostigmine. The novelty of the current case resides in the fact that, to the best of our knowledge, appears to be the first case of MG clinically manifested after COVID-19 infection in a fully vaccinated patient.

SARS-CoV-2 vaccination and new-onset myasthenia gravis: A report of 7 cases and review of the literature

Myasthenia gravis (MG) is an antibody-mediated immune disorder of the neuromuscular junction. SARS-CoV-2 is now recognised as a trigger factor for autoimmune diseases and to cause immune-mediated dysregulation, likely due to molecular mimicry induced by viral antigens. SARS-CoV-2 vaccination, similarly, results in exposure to viral antigen. Here we report 7 cases of new-onset myasthenia gravis in timely association with SARS-CoV-2 vaccination, including the first paediatric case identified to date. We also reviewed the literature for other new-onset MG cases reported within 4 weeks of SARS-CoV-2 vaccination and discuss our findings in the context of altered (auto)immunity following SARS-CoV-2 vaccination and/or infection.

Case Report: Functional Outcome of COVID-19 Subjects With Myasthenia Gravis and Critical Illness Polyneuropathy

Background

The COVID-19 disease can affect subjects suffering from myasthenia gravis (MG) and worsen its clinical course, leading to intensive care unit (ICU) admission. Critically ill subjects can develop a neuromuscular complication called ICU-acquired weakness (ICUAW). This disorder has also been detected in ICU subjects with COVID-19, but the association between MG and ICUAW has never been described in critically ill patients. We describe the case and functional outcome of a COVID-19 patient suffering from MG who developed critical illness polyneuropathy (CIP).

Case Presentation

A 66-year-old man with a history of hypertension and ocular MG had COVID-19 and required ICU admission. The patient underwent mechanical ventilation and tracheotomy and was treated with remdesivir and corticosteroids. Fifteen days after admission, he complained of tetraparesis without the ocular involvement that remained unchanged despite the increase in anticholinesterase therapy. The length of stay (LOS) in ICU was 35 days. On day 2 of admission, the patient underwent a frontal muscle jitter study that confirmed the MG, and electroneurography (ENG) and electromyography (EMG) that showed overlapping ICUAW with electrophysiological signs characteristic of CIP. The cerebrospinal fluid (CSF) showed normal pressure, cell count, and protein levels (&lt;45 mg/dl) without albumin-cytologic disassociation. The CSF/serum glucose ratio was normal. The CSF culture for possible organisms, laboratory tests for autoimmune disorders, the panel of antiganglioside antibodies, and the paraneoplastic syndrome were negative. Strength and functional outcomes were tested with the MRC scale, the DRS, Barthel scale, and the Functional Independence Measure (FIM) at admission, discharge, and follow-up. Muscular strength improved progressively, and the MRC scale sum-score was 50 at discharge. Anticholinesterase therapy with pyridostigmine at a dosage of 30 mg 3 times daily, which the patient was taking before COVID-19, was resumed. His motor abilities recovered, and functional evaluations showed full recovery at follow-up.

Conclusion

In the described subject, the coexistence of both neuromuscular disorders did not affect the clinical course and recovery, but the question remains about generalization to all patients with MG. The rehabilitation interventions might have facilitated the outcome.

What is in the Neuromuscular Junction Literature?

ABSTRACT

This update covers a number of treatment topics starting with Fc receptor inhibitors and the Federal Drug Administration approval of efgartigimod. Some uncertainties regarding the use of corticosteroids are addressed, namely the risk of exacerbation with initiation of treatment and how to taper. The presence and potential importance of antibody overshoot following plasmapheresis is noted and the evolving increase in usefulness of acetylcholine receptor antibodies in diagnosing ocular myasthenia. Several recent series and case reports regarding coronavirus 2019 and myasthenia gravis are reviewed. The topics of myasthenia gravis and pregnancy, and another look at thymectomy in MG are provided. Finally, a couple of case reports on Lambert-Eaton myasthenic syndrome concentrate on the ice pack test and an autoantibody association with paraneoplastic cerebellar degeneration and Lambert-Eaton myasthenic syndrome in the same patient.

Skeletal Muscle and COVID-19: The Potential Involvement of Bioactive Sphingolipids

SARS-CoV-2 virus infection is the cause of the coronavirus disease 2019 (COVID-19), which is still spreading over the world. The manifestation of this disease can range from mild to severe and can be limited in time (weeks) or persist for months in about 30–50% of patients. COVID-19 is considered a multiple organ dysfunction syndrome and the musculoskeletal system manifestations are beginning to be considered of absolute importance in both COVID-19 patients and in patients recovering from the SARS-CoV-2 infection. Musculoskeletal manifestations of COVID-19 and other coronavirus infections include loss of muscle mass, muscle weakness, fatigue or myalgia, and muscle injury. The molecular mechanisms by which SARS-CoV-2 can cause damage to skeletal muscle (SkM) cells are not yet well understood. Sphingolipids (SLs) represent an important class of eukaryotic lipids with structural functions as well as bioactive molecules able to modulate crucial processes, including inflammation and viral infection. In the last two decades, several reports have highlighted the role of SLs in modulating SkM cell differentiation, regeneration, aging, response to insulin, and contraction. This review summarizes the consequences of SARS-CoV-2 infection on SkM and the potential involvement of SLs in the tissue responses to virus infection. In particular, we highlight the role of sphingosine 1-phosphate signaling in order to aid the prediction of novel targets for preventing and/or treating acute and long-term musculoskeletal manifestations of virus infection in COVID-19.

Autoantibodies Against Proteins Previously Associated With Autoimmunity in Adult and Pediatric Patients With COVID-19 and Children With MIS-C

The antibody profile against autoantigens previously associated with autoimmune diseases and other human proteins in patients with COVID-19 or multisystem inflammatory syndrome in children (MIS-C) remains poorly defined. Here we show that 30% of adults with COVID-19 had autoantibodies against the lung antigen KCNRG, and 34% had antibodies to the SLE-associated Smith-D3 protein. Children with COVID-19 rarely had autoantibodies; one of 59 children had GAD65 autoantibodies associated with acute onset of insulin-dependent diabetes. While autoantibodies associated with SLE/Sjögren's syndrome (Ro52, Ro60, and La) and/or autoimmune gastritis (gastric ATPase) were detected in 74% (40/54) of MIS-C patients, further analysis of these patients and of children with Kawasaki disease (KD), showed that the administration of intravenous immunoglobulin (IVIG) was largely responsible for detection of these autoantibodies in both groups of patients. Monitoring in vivo decay of the autoantibodies in MIS-C children showed that the IVIG-derived Ro52, Ro60, and La autoantibodies declined to undetectable levels by 45-60 days, but gastric ATPase autoantibodies declined more slowly requiring >100 days until undetectable. Further testing of IgG and/or IgA antibodies against a subset of potential targets identified by published autoantigen array studies of MIS-C failed to detect autoantibodies against most (16/18) of these proteins in patients with MIS-C who had not received IVIG. However, Troponin C2 and KLHL12 autoantibodies were detected in 2 of 20 and 1 of 20 patients with MIS-C, respectively. Overall, these results suggest that IVIG therapy may be a confounding factor in autoantibody measurements in MIS-C and that antibodies against antigens associated with autoimmune diseases or other human proteins are uncommon in MIS-C.

Post-COVID simultaneous onset of Graves' disease and ocular myasthenia gravis in a patient with a complex ocular motility impairment

A 74-years-old man experienced severe diplopia one month after recovery from an uncomplicated SARS-CoV-2 infection. Neurological examination was normal whereas ophthalmological examination showed bilateral exophthalmos with a complex ocular motility disorder characterized by a pseudo-internuclear ophthalmoplegia after fatigue associated to impairment of elevation and infraduction. Antibodies against TSH and acetylcholine receptors were positive; subsequent hormonal tests, ultrasonography of thyroid gland, single fiber electromyography and orbit MRI confirmed the diagnosis of concomitant Graves Disease (GD) and Myasthenia Gravis (MG). The coexistence between MG and GD is not rare but simultaneous onset after viral infection is very unsual. The complex ocular disorder simulated a deficit of the oculomotor nerve nuclei, and on clinical examination it posed some problems in the diagnosis. We suggest that recent SARS-COV-2 infection may have triggered a complex autoimmune response.

COVID-19 and the Peripheral Nervous System. A 2-year review from the pandemic to the vaccine era

Increasing literature has linked COVID‐19 to peripheral nervous system (PNS) diseases. In addition, as we move from the pandemic to the vaccination era, literature interest is shifting towards the potential association between COVID‐19 vaccines and PNS manifestations. We reviewed published literature on COVID‐19, COVID‐19 vaccines and PNS manifestations between 1 January 2020 and 1 December 2021. For Guillain‐Barré syndrome (GBS), isolated cranial neuropathy (ICN) and myositis associated with COVID‐19, the demographic, clinical, laboratory, electrophysiological and imaging features were included in a narrative synthesis. We identified 169 studies on COVID‐19‐associated complications, including 63 papers (92 patients) on GBS, 29 papers (37 patients) on ICN and 11 papers (18 patients) on myositis. Additional clinical phenotypes included chronic inflammatory demyelinating polyneuropathy, vasculitic neuropathies, neuralgic amyotrophy, critical care‐related complications, and myasthenia gravis. PNS complications secondary to COVID‐19 vaccines have been reported during randomized clinical trials, in real‐world case reports, and during large‐scale surveillance programs. These mainly include cases of GBS, Bell's palsy, and cases of neuralgic amyotrophy. Based on our extensive review of the literature, any conclusion about a pathophysiological correlation between COVID‐19 and PNS disorders remains premature, and solely supported by their temporal association, while epidemiological and pathological data are insufficient. The occurrence of PNS complications after COVID‐19 vaccines seems limited to a possible higher risk of facial nerve palsy and GBS, to a degree that widespread access to the ongoing vaccination campaign should not be discouraged, while awaiting for more definitive data from large‐scale surveillance studies.

Characteristics, treatment, and outcomes of Myasthenia Gravis in COVID-19 patients: A systematic review

Objective

Recent studies suggest that the clinical course and outcomes of patients with coronavirus disease 2019 (COVID-19) and myasthenia gravis (MG) are highly variable. We performed a systematic review of the relevant literature with a key aim to assess the outcomes of invasive ventilation, mortality, and hospital length of stay (HLoS) for patients presenting with MG and COVID-19.

Methods

We searched the PubMed, Scopus, Web of Science, and MedRxiv databases for original articles that reported patients with MG and COVID-19. We included all clinical studies that reported MG in patients with confirmed COVID-19 cases via RT-PCR tests. We collected data on patient background characteristics, symptoms, time between MG and COVID-19 diagnosis, MG and COVID-19 treatments, HLoS, and mortality at last available follow-up. We reported summary statistics as counts and percentages or mean±SD. When necessary, inverse variance weighting was used to aggregate patient-level data and summary statistics.

Results

Nineteen studies with 152 patients (mean age 54.4 ± 12.7 years; 79/152 [52.0%] female) were included. Hypertension (62/141, 44.0%) and diabetes (30/141, 21.3%) were the most common comorbidities. The mean time between the diagnosis of MG and COVID-19 was7.0 ± 6.3 years. Diagnosis of COVID-19 was confirmed in all patients via RT-PCR tests. Fever (40/59, 67.8%) and ptosis (9/55, 16.4%) were the most frequent COVID-19 and MG symptoms, respectively. Azithromycin and ceftriaxone were the most common COVID-19 treatments, while prednisone and intravenous immunoglobulin were the most common MG treatments. Invasive ventilation treatment was required for 25/59 (42.4%) of patients. The mean HLoS was 18.2 ± 9.9 days. The mortality rate was 18/152 (11.8%).

Conclusion

This report provides an overview of the characteristics, treatment, and outcomes of MG in COVID-19 patients. Although COVID-19 may exaggerate the neurological symptoms and worsens the outcome in MG patients, we did not find enough evidence to support this notion. Further studies with larger numbers of patients with MG and COVID-19 are needed to better assess the clinical outcomes in these patients.

Neuro-COVID-19

Neuromuscular manifestations of new coronavirus disease 2019 (COVID-19) infection are frequent, and include dizziness, headache, myopathy, and olfactory and gustatory disturbances. Patients with acute central nervous system disorders, such as delirium, impaired consciousness, stroke and convulsive seizures, have a high mortality rate. The encephalitis/encephalopathy that causes consciousness disturbance and seizures can be classified into three conditions, including direct infection with the SARS-CoV-2 virus, encephalopathy caused by central nervous system damage secondary to systemic hypercytokinemia (cytokine storm) and autoimmune-mediated encephalitis that occurs after infection. The sequelae, called post-acute COVID-19 syndrome or long COVID, include neuromuscular manifestations, such as anxiety, depression, sleep disturbance, muscle weakness, brain fog and cognitive impairment. It is desirable to establish diagnostic criteria and treatment for these symptoms. Vaccine-induced thrombotic thrombocytopenia, Guillain-Barré syndrome, bilateral facial paralysis, encephalitis and opsoclonus-myoclonus syndrome have been reported as adverse reactions after the COVID-19 vaccine, although these are rare.

Disorders of the Cholinergic System in COVID-19 Era-A Review of the Latest Research

The appearance of the SARS-CoV-2 virus initiated many studies on the effects of the virus on the human body. So far, its negative influence on the functioning of many morphological and physiological units, including the nervous system, has been demonstrated. Consequently, research has been conducted on the changes that SARS-CoV-2 may cause in the cholinergic system. The aim of this study is to review the latest research from the years 2020/2021 regarding disorders in the cholinergic system caused by the SARS-CoV-2 virus. As a result of the research, it was found that the presence of the COVID-19 virus disrupts the activity of the cholinergic system, for example, causing the development of myasthenia gravis or a change in acetylcholine activity. The SARS-CoV-2 spike protein has a sequence similar to neurotoxins, capable of binding nicotinic acetylcholine receptors (nAChR). This may be proof that SARS-CoV-2 can bind nAChR. Nicotine and caffeine have similar structures to antiviral drugs, capable of binding angiotensin-converting enzyme 2 (ACE 2) epitopes that are recognized by SARS-CoV-2, with the potential to inhibit the formation of the ACE 2/SARS-CoV-2 complex. The blocking is enhanced when nicotine and caffeine are used together with antiviral drugs. This is proof that nAChR agonists can be used along with antiviral drugs in COVID-19 therapy. As a result, it is possible to develop COVID-19 therapies that use these compounds to reduce cytokine production. Another promising therapy is non-invasive stimulation of the vagus nerve, which soothes the body’s cytokine storm. Research on the influence of COVID-19 on the cholinergic system is an area that should continue to be developed as there is a need for further research. It can be firmly stated that COVID-19 causes a dysregulation of the cholinergic system, which leads to a need for further research, because there are many promising therapies that will prevent the SARS-CoV-2 virus from binding to the nicotinic receptor. There is a need for further research, both in vitro and in vivo. It should be noted that in the functioning of the cholinergic system and its connection with the activity of the COVID-19 virus, there might be many promising dependencies and solutions.

New onset of generalized myasthenia gravis developed after a new coronavirus infection (COVID-19)

Development of various immune-mediated neurological complications after a viral infection is of particular interest to medical society during a pandemic of COVID-19. It was found that SARS-CoV-2 has the ability to cause hyperstimulation of the immune system, thereby initiating developing of autoimmune diseases. The article describes a clinical case of new onset of generalized myasthenia gravis with thymoma in a patient after previous COVID-19. 

Neurological update: COVID-19

Coronavirus Disease 2019 is predominantly a disorder of the respiratory system, but neurological complications have been recognised since early in the pandemic. The major pathophysiological processes leading to neurological damage in COVID-19 are cerebrovascular disease, immunologically mediated neurological disorders and the detrimental effects of critical illness on the nervous system. It is still unclear whether direct invasion of the nervous system by the Severe Acute Respiratory Syndrome Coronavirus 2 occurs; given the vast numbers of people infected at this point, this uncertainty suggests that nervous system infection is unlikely to represent a significant issue if it occurs at all. In this review, we explore what has been learnt about the neurological complications of COVID-19 over the course of the pandemic, and by which mechanisms these complications most commonly occur.

SARS-CoV-2 Proteome Harbors Peptides Which Are Able to Trigger Autoimmunity Responses: Implications for Infection, Vaccination, and Population Coverage

Autoimmune diseases (ADs) could occur due to infectious diseases and vaccination programs. Since millions of people are expected to be infected with SARS-CoV-2 and vaccinated against it, autoimmune consequences seem inevitable. Therefore, we have investigated the whole proteome of the SARS-CoV-2 for its ability to trigger ADs. In this regard, the entire proteome of the SARS-CoV-2 was chopped into more than 48000 peptides. The produced peptides were searched against the entire human proteome to find shared peptides with similar experimentally confirmed T-cell and B-cell epitopes. The obtained peptides were checked for their ability to bind to HLA molecules. The possible population coverage was calculated for the most potent peptides. The obtained results indicated that the SARS-CoV-2 and human proteomes share 23 peptides originated from ORF1ab polyprotein, nonstructural protein NS7a, Surface glycoprotein, and Envelope protein of SARS-CoV-2. Among these peptides, 21 peptides had experimentally confirmed equivalent epitopes. Amongst, only nine peptides were predicted to bind to HLAs with known global allele frequency data, and three peptides were able to bind to experimentally confirmed HLAs of equivalent epitopes. Given the HLAs which have already been reported to be associated with ADs, the ESGLKTIL, RYPANSIV, NVAITRAK, and RRARSVAS were determined to be the most harmful peptides of the SARS-CoV-2 proteome. It would be expected that the COVID-19 pandemic and the vaccination against this pathogen could significantly increase the ADs incidences, especially in populations harboring HLA-B*08:01, HLA-A*024:02, HLA-A*11:01 and HLA-B*27:05. The Southeast Asia, East Asia, and Oceania are at higher risk of AD development.

Temporal association between SARS-CoV-2 and new-onset myasthenia gravis: is it causal or coincidental?

Several case reports of COVID-19 in patients with myasthenia gravis (MG) have been documented. However, new-onset autoimmune MG following COVID-19 has been reported very rarely. We report one such case here. A 65-year-old man presented to us with dysphagia 6 weeks following mild COVID-19. He was evaluated and diagnosed as antiacetylcholine receptor antibody (AchR) positive, non-thymomatous, generalised MG. He subsequently developed myasthenic crisis and improved after treatment with intravenous immunoglobulin, prednisolone and pyridostigmine. Systematic literature review showed eight more similar cases. Analysis of all cases including the one reported here showed these features: mean age 55.8 years, male gender (5), time interval between COVID-19 and MG (5-56 days), generalised (5), bulbar and/or ocular symptoms (4), anti-AchR antibodies (7) and antimuscle-specific kinase antibodies (2). All have improved with immunotherapy. Although, many hypothesis are proposed to explain causal relationship between the two, it could as well be sheer coincidence.

COVID-19 and Myositis: What We Know So Far

PURPOSE

Myositis as a rare manifestation of COVID-19 is only recently being reported. This review examines the current literature on COVID-19-induced myositis focusing on etiopathogenesis, clinical presentations, diagnostic practices, and therapeutic challenges with immunosuppression, and the difficulties experienced by rheumatologists in established myositis in the COVID-19 era.

RECENT FINDINGS

COVID-19 is associated with a viral myositis attributable to direct myocyte invasion or induction of autoimmunity. COVID-19-induced myositis may be varied in presentation, from typical dermatomyositis to rhabdomyolysis, and a paraspinal affliction with back pain. It may or may not present with acute exponential elevations of enzyme markers such as creatine kinase (CK). Virus-mediated muscle inflammation is attributed to ACE2 (angiotensin-converting enzyme) receptor-mediated direct entry and affliction of muscle fibers, leading on to innate and adaptive immune activation. A greater recognition of the stark similarity between anti-MDA5-positive myositis with COVID-19 has thrown researchers into the alley of exploration - finding common etiopathogenic basis as well as therapeutic strategies. For patients with established myositis, chronic care was disrupted during the pandemic with several logistic challenges and treatment dilemmas leading to high flare rates. Teleconsultation bridged the gap while ushering in an era of patient-led care with the digital transition to tools of remote disease assessment. COVID-19 has brought along greater insight into unique manifestations of COVID-19-related myositis, ranging from direct virus-induced muscle disease to triggered autoimmunity and other etiopathogenic links to explore. A remarkable shift in the means of delivering chronic care has led patients and caregivers worldwide to embrace a virtual shift with teleconsultation and opened doorways to a new era of patient-led care.

MuSK-positive myasthenia may not only be triggered by SARS-CoV-2

With interest we read the article by Assini et al, about a 77 years old male who developed ptosis, diplopia, dysarthria, and chewing difficulty 2 months after a mild infection with SARS-CoV-2, manifesting with fever and bilateral pneumonia (COVID-19) without necessitating continuous positive airway pressure (CPAP), bilevel positive airway pressure (BIPAP), or mechanical ventilation [1] Work-up revealed muscle-specific tyrosine-kinase (MuSK) positive myasthenia gravis (MG) (MuSK-MG), which did not respond to pyridostigmin but to azathioprine [1]. We have the following comments and concerns.