Interleukin-27 levels in patients with myasthenia gravis

Interleukin-27 (IL-27), which belongs to IL-12 family, influences the function of T cells (Tregs) through regulating the expression, and function of forkhead box P3 (FoxP3). In this study, we detected the IL-27 serum levels in 59 myasthenia gravis (MG) patients and 35 healthy controls (HCs). Among them, 32 MG patients received immunoglobulin intravenous (IVIG) injections (0.4 g/kg per day for 5 consecutive days). IL-27 levels were collected before and after the treatments and subjected to a comparative study. Finally, we assessed the correlations of IL-27 levels with the clinical characteristics of MG. As a result, serum IL-27 levels were significantly higher in MG patients than those in the HCs. Meanwhile, significant reduction was detected after the IVIG treatment. IL-27 levels positively correlated with both MG activities of daily living and quantitative MG score. IL-27 may participate in the pathogenesis of MG and can be used as an early marker for the diagnosis and prognosis of MG. In addition, IL-27 can be used as a target for MG treatment through the regulation of specific immune signaling and maintaining immune homeostasis.

Immunoregulatory Cells in Myasthenia Gravis

Myasthenia gravis (MG) is a T cell-dependent, B-cell mediated autoimmune disease caused by antibodies against the nicotinic acetylcholine receptor or other components of the post-synaptic muscle endplate at the neuromuscular junction. These specific antibodies serve as excellent biomarkers for diagnosis, but do not adequately substitute for clinical evaluations to predict disease severity or treatment response. Several immunoregulatory cell populations are implicated in the pathogenesis of MG. The immunophenotype of these populations has been well-characterized in human peripheral blood. CD4⁺FoxP3⁺ regulatory T cells (Tregs) are functionally defective in MG, but there is a lack of consensus on whether they show numerical perturbations. Myeloid-derived suppressor cells (MDSCs) have also been explored in the context of MG. Adoptive transfer of CD4⁺FoxP3⁺ Tregs or MDSCs suppresses ongoing experimental autoimmune MG (EAMG), a rodent model of MG, suggesting a protective role of both populations in this disease. An imbalance between follicular Tregs and follicular T helper cells is found in untreated MG patients, correlating with disease manifestations. There is an inverse correlation between the frequency of circulating IL-10–producing B cells and clinical status in MG patients. Taken together, both functional and numerical defects in various populations of immunoregulatory cells in EAMG and human MG have been demonstrated, but how they relate to pathogenesis and whether these cells can serve as biomarkers of disease activity in humans deserve further exploration.

Case Report: Orbital Myositis and Myasthenia Gravis as Symptoms of Immune Reconstitution Inflammatory Syndrome in a Patient With Human Immunodeficiency Virus Infection

We present a case of a 37-year-old man with HIV infection who had been on antiretroviral therapy for one year. He was admitted to our hospital with red and swollen eyes, acute onset progressive exophthalmos, and intermittent diplopia endured for 7 days. His symptoms, exam, and imaging led to a diagnosis of immune reconstitution inflammatory syndrome associated orbital myositis. His symptoms improved considerably after glucocorticoid therapy. Following a reduction in the oral prednisone dose, he re-presented with left ptosis, which rapidly progressed to bilateral ptosis. Diagnostic testing led to the diagnosis of immune mediated myasthenia gravis. Treatment with pyridostigmine bromide, prednisone, and tacrolimus was initiated. One month later, the patient's symptoms improved significantly. There was a probable association between his symptoms and autoimmune immune reconstitution inflammatory syndrome. This report highlights the importance of recognizing autoimmune disorders in human immunodeficiency virus-infected patients undergoing antiretroviral therapy. Orbital myositis and myasthenia gravis in human immunodeficiency virus-infected patients correlate closely with immunity status following a marked increase in CD4⁺ T cell counts.

Jobb oldali videoasszisztált thoracoscopos thymectomia a thymoma nélküli, felnőttkori myasthenia gravis sebészi kezelésében

Összefoglaló. Bevezetés: A myasthenia gravis javallatával végzett csecsemőmirigy-eltávolítás sebésztechnikai szempontból lényegesen megváltozott az elmúlt közel 30 évben. A standard műtétnek számító transsternalis és transcervicalis thymectomia mellett elterjedt a videoasszisztált thoracoscopos sebészeti (VATS), később pedig a robot sebészeti megoldás is. Két intézetünkben 2011-2012-ben vezettük be a VATS thymectomiát. Módszer: A többféle technikai megoldás közül a mediastinumot a jobb mellüreg felől megközelítő utat választottuk. Eleinte 3, később 2 pontos perimammaris portot készítettünk a thymus elérésére a beteg háton fekvő helyzetében. Minden esetben ultrahangos vágóeszközt alkalmaztunk. Kiterjesztett thymectomiára törekedve a perithymikus zsírszövetet is eltávolítottuk, szélesen megnyitva a bal oldali mellüreget is. A betegek kiválasztásában az átlagos testsúlyú vagy soványabb betegeket részesítettük előnyben. Eredmények: 8 év és 4 hónap alatt 92 beteget műtöttünk a fenti módszerrel thymoma nélküli myasthenia gravis alapbetegséggel. 20 férfi és 72 nő. Átlagéletkor 33,1 év (19-75 év). A műtéti idő 35-160 percig terjedt, átlagosan 82,3 perc volt. A tömegesebb mediastinalis zsírszövet néhány betegnél nehezítette a tájékozódást és a maradéktalan eltávolítást. Műtét alatt 4 esetben érsérülés és 3 ellenoldali tüdősérülés következett be. Két konverziót végeztünk (1-1 sternotomia és thoracotomia). Idegsérülés nem történt. Tíz beteg igényelt néhány órás művi lélegeztetést a műtét után, a többi beteget a műtőasztalon extubáltuk. Reintubáció, tracheostomia, légzési elégtelenség, műtéti halálozás nem volt. Az intenzív ápolási idő átlaga: 1,1 (0-11) nap. A teljes kórházi ápolási idő átlaga: 4,8 (3-15) nap. A drenázsidő 1-4 nap, átlagosan 1,16 nap. Két beteg (2,41%) halt meg a műtétet követően 1 és 5 éven belül. További 81 beteg 12-108 (átlag: 48) hónapos követése során a myastheniás állapotban 21 (25,3%) betegnél komplett, 4 (4,82%) betegnél gyógyszeres remisszió, 20 (24,1%) betegnél minimális manifesztáció, 28 (33,73%) betegnél egyéb javulás volt megállapítható. 4 (4,82%) beteg állapota változatlan maradt, 4 (4,82%) betegé pedig romlott. Következtetés: A VATS thymectomia teljesen új utat jelent a transsternalis módszerben járatos sebészek számára. A tömegesebb mediastinalis zsírszövet nagyon megnehezíti a műtétet. A perioperatív szak nagyon kedvező a betegek számára, és a késői eredmények is elfogadhatóak. Kérdéses, hogy a thymus minden esetben maradéktalanul eltávolítható-e ezzel a módszerrel.

SUMMARY

INTRODUCTION

Surgical technique of thymectomy performed for treatment of myasthenia gravis has considerably changed in the last almost 30 years. In addition to standard interventions - transsternal and transcervical thymectomy -, video-assisted thoracoscopic interventions (VATS), later on robotic surgery came into general use. In our two institutions, we apply VATS thymectomy since 2011.

METHODS

There are several different surgical techniques for this purpose; we approached the mediastinum through the right thoracic cavity. We prepared initially 3, later on 2 perimammal ports for the access of the thymus; the patients were in supine position during surgery. We used an ultrasonic cutting device in all cases. In order to perform extended thymectomy, we removed the fatty tissue around the thymus and opened widely the left thoracic cavity, too. During patient enrollment, we preferred patients with normal or lower body weight.

RESULTS

During 8 years and 4 months, we operated on 92 patients using this method for myasthenia gravis without thymoma; there were 20 male and 72 female patients at the age of 33 years on average (19-75 years). Duration of surgery was 35-160 minutes, 82.3 minutes on average. The bulky fatty tissue around the thymus made the orientation and the complete removal more difficult in a few patients. We experienced vascular injury in 4 cases and injury of the contralateral lung in 3 cases. Conversion was necessary in 2 cases (1 sternotomy and 1 thoracotomy), there were no nerve injuries. Assisted ventilation was necessary in case of ten patients in the postoperative period for a few hours; all other patients were extubated on the operating table. There was no need for repeated intubation and tracheostomy; there was no respiratory insufficiency and perioperative mortality. Duration of ICU care was 1.1 days on the average (0-11 days), that of the total hospital care 4.8 days on average (3-15 days). Duration of thoracic drainage was 1.16 days on average (1-4 days). Two patients (2.41%) died within one and five years after surgery. During 12-108 months (48 months on average) follow-up of 81 patients, 21 patients (25.3%) suffering from myasthenia total recovery was observed, pharmacologic remission was achieved in 4 patients (5.3%), minimal manifestation remained in 23 patients (24.1%), while in 28 patients (33.73%) other improvement was observed. The status of 4 patients (4.82%) remained unchanged and that of 4 patients (5.3%) worsened.

CONCLUSION

VATS thymectomy represents a completely new surgical method for surgeons having experience in transsternal surgical technique. Bulky mediastinal fatty tissue makes surgery very difficult. The perioperative period is advantageous for the patients and also the long term follow-up results are acceptable. It is questionable that the thymus can be completely removed with this method in all cases.

Double vision in Parkinson's Disease: a systematic review

INTRODUCTION

The prevalence of diplopia in Parkinson's disease (PD) ranges from 10% to 30%. Diplopia is usually limited to specific situations such as reading and looking around, however, it can also be constant. The aim of this review, supplemented by two case studies, was to summarise current knowledge on the frequency, possible causes, differential diagnosis, pathophysiology and treatment approaches to double vision in PD patients.

METHODOLOGY

An electronic search (PubMed, Scopus, Embase and Web of Science) to identify studies regarding diplopia in PD patients was performed in May 2020. The following search terms were used: Parkinson's Disease and diplopia.

RESULTS

Five articles are included in this literature review. In the literature, the number of included patients with PD who presented with symptoms of diplopia varied from a single case report to 88 patients. Diplopia was usually intermittent and binocular. The most commonly reported type of diplopia was single object diplopia, and the second most common was complete diplopia. Risk factors contributing to developing diplopia were: older age, disease duration, disease severity, cognitive decline, presence of visual hallucinations, and higher levodopa equivalent dose. Results also showed that diplopia had a significant impact on quality of life. Possible comorbidities of diplopia include myasthenia gravis and vascular disease.

CONCLUSION

Diplopia is relatively common in PD, but still understudied. The research shows that it has a clear impact on health-related quality of life and patient safety. The acute onset of diplopia should always result in tests to exclude other diseases. Tailored interventions should be developed, leading to improved patient safety, quality of life, and quality of care.

The Neuromuscular Junction in Health and Disease: Molecular Mechanisms Governing Synaptic Formation and Homeostasis

The neuromuscular junction (NMJ) is a highly specialized synapse between a motor neuron nerve terminal and its muscle fiber that are responsible for converting electrical impulses generated by the motor neuron into electrical activity in the muscle fibers. On arrival of the motor nerve action potential, calcium enters the presynaptic terminal, which leads to the release of the neurotransmitter acetylcholine (ACh). ACh crosses the synaptic gap and binds to ACh receptors (AChRs) tightly clustered on the surface of the muscle fiber; this leads to the endplate potential which initiates the muscle action potential that results in muscle contraction. This is a simplified version of the events in neuromuscular transmission that take place within milliseconds, and are dependent on a tiny but highly structured NMJ. Much of this review is devoted to describing in more detail the development, maturation, maintenance and regeneration of the NMJ, but first we describe briefly the most important molecules involved and the conditions that affect their numbers and function. Most important clinically worldwide, are myasthenia gravis (MG), the Lambert-Eaton myasthenic syndrome (LEMS) and congenital myasthenic syndromes (CMS), each of which causes specific molecular defects. In addition, we mention the neurotoxins from bacteria, snakes and many other species that interfere with neuromuscular transmission and cause potentially fatal diseases, but have also provided useful probes for investigating neuromuscular transmission. There are also changes in NMJ structure and function in motor neuron disease, spinal muscle atrophy and sarcopenia that are likely to be secondary but might provide treatment targets. The NMJ is one of the best studied and most disease-prone synapses in the nervous system and it is amenable to in vivo and ex vivo investigation and to systemic therapies that can help restore normal function.

Roles of cytokines and T cells in the pathogenesis of myasthenia gravis

Myasthenia gravis (MG) is characterized by muscle weakness and fatigue caused by the presence of autoantibodies against the acetylcholine receptor (AChR) or the muscle-specific tyrosine kinase (MuSK). Activated T, B and plasma cells, as well as cytokines, play important roles in the production of pathogenic autoantibodies and the induction of inflammation at the neuromuscular junction in MG. Many studies have focused on the role of cytokines and lymphocytes in anti-AChR antibody-positive MG. Chronic inflammation mediated by T helper type 17 (Th17) cells, the promotion of autoantibody production from B cells and plasma cells by follicular Th (Tfh) cells and the activation of the immune response by dysfunction of regulatory T (T_reg ) cells may contribute to the exacerbation of the MG pathogenesis. In fact, an increased number of Th17 cells and Tfh cells and dysfunction of T_reg cells have been reported in patients with anti-AChR antibody-positive MG; moreover, the number of these cells was correlated with clinical parameters in patients with MG. Regarding cytokines, interleukin (IL)-17; a Th17-related cytokine, IL-21 (a Tfh-related cytokine), the B-cell-activating factor (BAFF; a B cell-related cytokine) and a proliferation-inducing ligand (APRIL; a B cell-related cytokine) have been reported to be up-regulated and associated with clinical parameters of MG. This review focuses on the current understanding of the involvement of cytokines and lymphocytes in the immunological pathogenesis of MG, which may lead to the development of novel therapies for this disease in the near future.

[Clinical course of myasthenia gravis at the department of neurology in Antananarivo Madagascar]

Introduction

myasthenia gravis (MG) is a rare disease affecting the neuromuscular junction. It can lead to a life-threatening condition, especially when it is associated with respiratory failure. Full remission is possible with treatment. Our aims are to describe the clinical course of patients with MG with under treatment, in order to further improve management and to implement a database of patients living in Madagascar.

Methods

we conducted a descriptive retrospective study in the Department of Neurology at the Befelatanana Antananarivo University Hospital Center between January 2010 and December 2017. This study involved all patients diagnosed with MG based on positive prostigmin test.

Results

among the 5814 hospitalized patients, 25 (0,42%) were included. Only 16 patients were on follow-up (64%) of whom 14 were receiving medical treatment. Three of them had undergone thymectomy. The mean follow-up period was 24 months. Among treated patients, 8 improved and 2 died. Among thymectomized patients, 2 improved and 1 died.

Conclusion

myasthenia gravis is a rare but serious disease. Improvement is possible with treatment even in the absence of adequate technical equipment for its management in Madagascar. Currently, a campaign in partnership with Myasthenia Gravis Association in Madagascar is underway for breathing devices useful especially when myasthenic crises occur.

Anesthesia and Perioperative Considerations for Patients With Myasthenia Gravis

Patients with neuromuscular diseases such as myasthenia gravis can present as complicated anesthetic cases. This article reviews anesthetic considerations for optimal perioperative care of patients with myasthenia gravis. The pathophysiology of myasthenia gravis, cholinergic and myasthenic crises, and perioperative management are discussed; this includes the pharmacology of acetylcholinesterase inhibitors vs sugammadex, extubation criteria, pain management, and risk factors for postoperative myasthenic crisis. Anesthesia recommendations include reversal of nondepolarizing neuromuscular blockade agents with sugammadex, obtaining sufficient spontaneous breathing with absolutely no residual curarization before extubation, limited use of opioids and sedatives, avoidance of routine admission to the intensive care unit, and consideration of peripheral nerve blocks for adjunct pain control.

Myasthenia gravis therapy with individualized homeopathy: A case report

We present a 61-year-old man with severe myasthenia gravis, nonresponsive to conventional therapy. The patient was treated with individualized homeopathy, demonstrating significant improvement on his clinical status and no disease symptoms.

Macrophage Activation Syndrome in a Case of Myasthenia Gravis with Concurrent Cytomegalovirus Infection

OBJECTIVE

Macrophage activation syndrome (MAS) or reactive hemophagocytic lymphohistiocytosis (HLH) refers to a set of clinical symptoms caused by the excessive activation and proliferation of macrophages. It was linked with autoimmune disease such as systemic-onset juvenile rheumatoid arthritis, systemic lupus erythematosus, rheumatoid arthritis, and dermatomyositis, etc. Herein we report a case of myasthenia gravis (MG) with concurrent cytomegalovirus (CMV) infection developed MAS.

CASE REPORT

A 31-year-old female with history of MG for 2 years under stable control with azathioprine and prednisolone. She presented with persistent high fever for 2 weeks after an upper respiratory infection. Lab data revealed pancytopenia, elevated triglyceride, ferritin and C-reactive protein (CRP). A bone marrow aspiration confirmed hemophagocytosis. Investigation for occult infection revealed her plasma was positive for CMV IgG and IgM, and high for CMV viral load. She was then treated with 5 sessions of plasmapheresis and pulse steroid. Azathioprine was discontinued and replaced with cyclosporine. Gancylovir was given for her concurrent CMV infection. After 2 weeks of treatment, her fever gradually subsided, and her blood cell count, hepatobiliary enzymes, ferritin and CRP have returned to normal range. She was discharged in good recovery.

CONCLUSION

MAS is a rare complication of systemic autoimmune disease with poor prognosis, which may be precipitated by concurrent infection. Early recognition of this syndrome and prompt immune modulation therapy is crucial for successful treatment.

Serum level of soluble urokinase plasminogen activator receptor (suPAR) as a disease severity marker of myasthenia gravis: a pilot study

Myasthenia gravis (MG) is an autoantibody-mediated inflammatory disease of the neuromuscular junction. Biomarkers indicating disease activity in MG are warranted. Recently, the soluble urokinase plasminogen activator receptor (suPAR) has been reported to be associated with inflammation, tissue damage, disease activity and prognosis in various diseases, including autoimmune diseases. In this study, serum suPAR levels were measured in 40 patients with anti-acetylcholine receptor antibody-positive MG and 30 controls, and their correlations with clinical variables and severity scale scores were investigated. We identified that serum suPAR levels significantly correlated with MG activities of daily living scale (Spearman's ρ = 0·45; P = 0·004) and MG Foundation of America classification (Spearman's ρ = 0·37; P = 0·02) at serum sampling, but not with anti-acetylcholine receptor antibody titers. In conclusion, serum suPAR levels can be a candidate for a novel biomarker of disease activity in anti-acetylcholine receptor antibody-positive MG.

When to suspect a thymoma: clinical point of view

The thymus plays a crucial role in the development of immune system, regulating the maturation, selection and migration of T lymphocytes. Alterations in lymphatic content and structure of the thymus are observed in many autoimmune diseases. Moreover, changes of the epithelial component may cause the development of thymic tumours. Thymoma is a rare epithelial tumor of the anterior mediastinal compartment with a wide spectrum of clinical presentations. The causes of thymoma are still unknown and several hypotheses have been formulated. Thymomas show a variable course causing, frequently, a prolonged clinical history. The presence of metastasis at the time of diagnosis is very uncommon. Even if about 30% of the patients with thymoma are asymptomatic, they may have local symptoms (such as cough, pain, hoarseness, and dyspnea) or paraneoplastic disorders. The role of immune system in the pathogenesis of these tumors and related paraneoplastic syndromes is not completely clear. A clinical diagnosis, especially if the first manifestation is a thymoma-associated paraneoplastic disease, is not always easy and should be supported by an appropriate imaging in order to guide the proper management for each patient. In this article, we would like to give an overview of the local and systemic clinical manifestations, which can be found in patients affected by thymoma.

Thymus-derived B cell clones persist in the circulation after thymectomy in myasthenia gravis

Myasthenia gravis (MG) is a neuromuscular, autoimmune disease caused by autoantibodies that target postsynaptic proteins, primarily the acetylcholine receptor (AChR) and inhibit signaling at the neuromuscular junction. The majority of patients under 50 y with AChR autoantibody MG have thymic lymphofollicular hyperplasia. The MG thymus is a reservoir of plasma cells that secrete disease-causing AChR autoantibodies and although thymectomy improves clinical scores, many patients fail to achieve complete stable remission without additional immunosuppressive treatments. We speculate that thymus-associated B cells and plasma cells persist in the circulation after thymectomy and that their persistence could explain incomplete responses to resection. We studied patients enrolled in a randomized clinical trial and used complementary modalities of B cell repertoire sequencing to characterize the thymus B cell repertoire and identify B cell clones that resided in the thymus and circulation before and 12 mo after thymectomy. Thymus-associated B cell clones were detected in the circulation by both mRNA-based and genomic DNA-based sequencing. These antigen-experienced B cells persisted in the circulation after thymectomy. Many circulating thymus-associated B cell clones were inferred to have originated and initially matured in the thymus before emigration from the thymus to the circulation. The persistence of thymus-associated B cells correlated with less favorable changes in clinical symptom measures, steroid dose required to manage symptoms, and marginal changes in AChR autoantibody titer. This investigation indicates that the diminished clinical response to thymectomy is related to persistent circulating thymus-associated B cell clones.

Myasthenia Gravis: Autoantibody Specificities and Their Role in MG Management

Myasthenia gravis (MG) is the most common autoimmune disorder affecting the neuromuscular junction, characterized by skeletal muscle weakness and fatigability. It is caused by autoantibodies targeting proteins of the neuromuscular junction; ~85% of MG patients have autoantibodies against the muscle acetylcholine receptor (AChR-MG), whereas about 5% of MG patients have autoantibodies against the muscle specific kinase (MuSK-MG). In the remaining about 10% of patients no autoantibodies can be found with the classical diagnostics for AChR and MuSK antibodies (seronegative MG, SN-MG). Since serological tests are relatively easy and non-invasive for disease diagnosis, the improvement of methods for the detection of known autoantibodies or the discovery of novel autoantibody specificities to diminish SN-MG and to facilitate differential diagnosis of similar diseases, is crucial. Radioimmunoprecipitation assays (RIPA) are the staple for MG antibody detection, but over the past years, using cell-based assays (CBAs) or improved highly sensitive RIPAs, it has been possible to detect autoantibodies in previously SN-MG patients. This led to the identification of more patients with antibodies to the classical antigens AChR and MuSK and to the third MG autoantigen, the low-density lipoprotein receptor-related protein 4 (LRP4), while antibodies against other extracellular or intracellular targets, such as agrin, K_v1.4 potassium channels, collagen Q, titin, the ryanodine receptor and cortactin have been found in some MG patients. Since the autoantigen targeted determines in part the clinical manifestations, prognosis and response to treatment, serological tests are not only indispensable for initial diagnosis, but also for monitoring treatment efficacy. Importantly, knowing the autoantibody profile of MG patients could allow for more efficient personalized therapeutic approaches. Significant progress has been made over the past years toward the development of antigen-specific therapies, targeting only the specific immune cells or autoantibodies involved in the autoimmune response. In this review, we will present the progress made toward the development of novel sensitive autoantibody detection assays, the identification of new MG autoantigens, and the implications for improved antigen-specific therapeutics. These advancements increase our understanding of MG pathology and improve patient quality of life by providing faster, more accurate diagnosis and better disease management.

Challenges in diagnosing coexisting ocular myasthenia gravis and thyroid eye disease

Ocular myasthenia gravis (OMG) and thyroid eye disease are two autoimmune conditions that have several overlapping clinical features, and these coexist with a small but not insignificant frequency. Segregating these diagnoses is typically straightforward, but, when the two diseases co-occur in the same individual, making a diagnosis of OMG can be very challenging. In this review we address what is known about the coexistence of OMG and thyroid eye disease and we highlight the clinical features that are suggestive of overlapping conditions. We also describe the major testing approaches used in the diagnosis of these two entities, with special emphasis on the potential shortcomings of individual tests in patients with overlapping disease. In patients with thyroid eye disease, securing a diagnosis of OMG may not be possible on the basis of a single positive test. A multimodal approach using clinical, serologic, imaging, and electrodiagnostic data, is typically required.

[A case of anti-MuSK positive MG with recurrent right-sided heart failure as the initial manifestation]

We report a case of anti-MuSK antibody (Ab)-positive myasthenia gravis (MG) in a patient who developed recurrent right-sided congestive heart failure. The patient presented with right-sided congestive heart failure of unknown etiology, necessitating hospitalization on three occasions over a 6-month period. During the third episode of hospitalization, she developed disturbance of consciousness, and heart failure was attributed to carbon dioxide narcosis. We performed various investigations including an anti-MuSK Ab assay, which showed positive results, and she was diagnosed with MG based solely on anti-MuSK Ab positivity. Selective plasma exchange did not produce a satisfactory therapeutic effect, and she received additional intravenous immunoglobulin, plasmapheresis, and oral immunosuppressive therapy after which she was successfully weaned off the ventilator. This case report highlights the following points: (a) Recurrent right-sided congestive heart failure may be the first manifestation of anti-MuSK Ab-positive MG and, (b) detection of the anti-MuSK Ab alone is a convincing rationale to diagnose patients with MG.

Myasthenia Gravis Is Not an Independent Prognostic Factor of Thymoma: Results of a Propensity Score Matching Trial of 470 Patients

Objective

The association between the prognosis of thymoma and MG remains controversial. Differences in clinical characteristics and treatments between patients with and without MG may affect the findings of those studies. We designed this propensity score matching trial to investigate whether MG is an independent prognostic predictor in thymoma.

Methods

Patients with pathologically diagnosed thymoma and MG were enrolled in the MG group. Moreover, the propensity score matching method was used to select patients who were diagnosed with thymoma without MG from the database of two participating centers. Matched factors included sex, age, Masaoka stage, pathological subtypes, and treatments. Matched patients were enrolled in the non-MG group. Chi-squared test was used to compare the characteristics of the two groups. Overall survival, local-regional relapse-free survival, distant metastasis-free survival, progression-free survival, and cancer-specific survival were calculated from the diagnosis of thymoma using the Kaplan–Meier method.

Results

Between April 1992 and October 2018, 235 patients each were enrolled in the MG and non-MG groups (1:1 ratio). The median ages of patients in the MG and non-MG groups were 46 years old. The World Health Organization pathological subtypes were well balanced between the two groups (B2 + B3: MG vs. non-MG group, 63.0 vs. 63.4%, p = 0.924). Most patients in both groups had Masaoka stages I–III (MG vs. non-MG group, 90.2 vs. 91.5%, p = 0.631). R0 resections were performed in 86.8 and 90.2% of the MG and non-MG groups, respectively (p = 0.247). The median follow-up time of the two groups was 70.00 months (MG vs. non-MG group, 73.63 months vs. 68.00 months). Five-year overall survivals were 92.5 and 90.3%, 8-year overall survivals were 84.2 and 84.2%, and 10-year overall survivals were 80.2 and 81.4% (p = 0.632) in the MG and non-MG groups, respectively. No differences were found in the progression-free survival, distant metastasis-free survival, and local-regional relapse-free survival between the two groups.

Conclusion

MG is not an independent or direct prognostic factor of thymoma, although it might be helpful in diagnosis thymoma at an early stage, leading indirectly to better prognosis.

Neuromuscular Diseases Care in the Era of COVID-19

The COVID-19 pandemic has pushed health systems to their limit and forced readjustment of standards of care for different pathologies. Management of neuromuscular diseases becomes a challenge since most of them are chronic, disabling, progressive, and/or require immunosuppressive drugs. There are three main aspects of COVID-19 that affect neuromuscular diseases care. The first one relates to how SARS-CoV2 directly affects different neuromuscular pathologies. Respiratory weakness, as seen in myasthenia gravis, amyotrophic lateral sclerosis, and myopathies, and the use of immunomodulatory drugs (Myasthenia Gravis and Chronic Inflammatory Demyelinating Polyneuropathy) make this group of patients potentially more vulnerable. Secondly, safety measures also affect proper care, limiting care continuity, and physical rehabilitation (one of the essential aspects of myopathies treatment). Telemedicine can partially solve the problem allowing for a continuum of close care, avoiding unnecessary visits, and even guaranteeing the attention of professionals from tertiary care centers. However, one of the crucial steps in neuromuscular diseases is diagnosis, and in most scenarios, more than one face-to-face visit is needed. Lastly, the global COVID-19 situation will also have an economic impact on patients and their families. This situation is of particular concern given that neuromuscular diseases already present difficulties due to the scarcity of resources in terms of public healthcare and research.

Magnetic resonance imaging characteristics of thymoma in Vietnamese patients with myasthenia gravis in relation to histopathological type and disease staging

Introduction

Myasthenia gravis (MG) is a relatively uncommon neuromuscular disease. The thymus plays an important role in the pathogenesis of MG, with 70% of patients presenting with thymic follicular hyperplasia and 20% presenting with thymoma. This study aimed to characterize magnetic resonance (MR) images of thymomas in patients with MG, associated with various stages and types.

Material and methods

A prospective study was performed in 46 MG patients with thymoma, who underwent surgery between August 2014 and September 2018, in Vietnam. Differences in MR imaging (MRI) images, according to type and stage, were assessed by the χ² test or Fisher’s exact test and Student’s t-test. A p-value < 0.05 was considered significant.

Results

The proportions of each type of thymomas found to be invasive were 28.6%, 61.1%, 66.7%, 90.9%, and 100%, for type A, AB, B1, B2, and B3 thymomas, respectively. Heterogeneous signal intensities on T1- and T2-weighted images, necrosis, and cysts were more commonly observed in high-risk thymomas than in low-risk thymomas. Non-invasive thymomas were more likely to display smooth margins than invasive thymomas (p < 0.05). Only 16.7% of invasive thymomas were detected in MR findings.

Conclusions

Only a few characteristic MRI features could be used to differentiate thymomas by stage or type.

A new era for monoclonal antibodies with applications in neurology (Review)

Medical research continues to focus on developing specific treatment strategies, including biological products that are effective and have a good safety profile. Due to their novelty, an updated overall view is offered on some neurological diseases which benefit from monoclonal antibodies (mAbs), for better treatment in clinical decisions. An extensive literature review was performed using PubMed with the following search terms: 'monoclonal antibodies' and 'history of monoclonal antibodies' and 'monoclonal antibodies in neurology'. The following information was collected: the era before the discoveries of mAbs, the stage of implementation of biotechnologies for mAbs, and the clinical trials submitted at https://clinicaltrials.gov/ with patients suffering from neurological diseases treated with mAbs. Since 2004, mAbs have been used to treat several neurological diseases, yielding new therapeutic perspectives: natalizumab, alemtuzumab and ocrelizumab for multiple sclerosis, eculizumab for myasthenia gravis, erenumab and frenazumab for migraine, galcanezumab for migraine and cluster headache, eculizumab for neuromyelitis optica spectrum disorder. As in other cases, drug repurposing is applied to monoclonal antibodies, saving time and money. These innovative therapies are more effective and can treat previously untreatable diseases. As better understanding of the pathogenic mechanisms of neurological diseases is gained, additional mAbs are expected to be developed at a lower cost and with better safety profile compared with current treatment options.

Concentric Needle Jitter in 97 Myasthenia Gravis Patients

Objectives: To estimate the jitter parameters (single-fiber electromyography) in myasthenia gravis patients mostly by electrical activation in Frontalis, Orbicularis Oculi, and Extensor Digitorum muscles using a concentric needle electrode. Methods: Between 2009 and 2019, a total of 97 myasthenia gravis patients, 52 male, and mean age 54 years were included. Results: Any abnormal jitter parameter in individual muscles was 90.5% (Frontalis), 88.5% (Orbicularis Oculi), and 86.6% (Extensor Digitorum). Any jitter parameter combining Orbicularis Oculi and Frontalis muscle was abnormal in 100% for the ocular, and in 92.9% for the generalized myasthenia gravis. The most abnormal muscle was Orbicularis Oculi for the generalized, and Frontalis for the ocular myasthenia gravis. The decrement was abnormal in 78.4%, 85.9% for the generalized, and 25% for the ocular myasthenia gravis. The mean jitter ranged from 14.2 to 86 μs (mean 33.3 μs) for the ocular myasthenia gravis and from 14.4 to 220.4 μs (mean 66.3 μs) for the generalized myasthenia gravis. The antibody titers tested positive in 86.6%, 91.8% for the generalized, and 50% for the ocular myasthenia gravis. Thymectomy was done in 48.5%, thymoma was found in 19.6%, and myasthenic crisis occurred by 21.6%. Conclusion: The jitter parameters achieved a 100% abnormality in ocular myasthenia gravis if both the Orbicularis Oculi and Frontalis muscles were tested. There was a high jitter abnormality in generalized myasthenia gravis cases with one muscle tested, with about a 2% increase in sensitivity when a second is added. Concentric needle electrode jitter had high sensitivity similar to the single fiber electrode (93.8%), followed by antibody titers (86.6%), and abnormal decrement (78.4%).

Myasthenia Gravis Associated With Programmed Death-1 (PD-1) Receptor Inhibitor Pembrolizumab: A 40-day Case Report

PURPOSE

This case report describes myasthenia gravis-like symptoms after treatment with a programmed cell death 1 inhibitor, pembrolizumab, the treatment modalities utilized, and associated patient outcomes.

SUMMARY

A 76-year old male treated with pembrolizumab for palliative therapy for metastatic melanoma presented with increasing weakness, neck pain, diplopia in the left eye, abducens palsy, periorbital edema, and decreased appetite. The patient was diagnosed with acetylcholine receptor antibody (AChR) negative myasthenia gravis. The patient was started on prednisone 1 mg/kg/day, followed by pyridostigmine 60 mg by mouth 3 times a day, and IVIg for 5 days. Due to minor improvements in myasthenia gravis symptoms, 5 cycles of plasmapheresis were ordered. The patient was successfully treated for aspiration pneumonia after cardiopulmonary arrest. On day 28, the patient was diagnosed with ventilator associated pneumonia and received appropriate therapy. Due to ICU agitation and delirium, VAP, and long duration of treatment, the patient requested withdrawal of care and passed.

CONCLUSION

Programmed cell death inhibitors, such as pembrolizumab, can provide great benefit to patients but can also be associated with rare but serious adverse events. With new reports of MG after use, providers should continually weigh the benefits versus harm in using these products and monitor patients closely for such adverse events.

Thymoma-associated myasthenia gravis: Clinical features and predictive value of antiacetylcholine receptor antibodies in the risk of recurrence of thymoma

Background

Thymoma‐associated myasthenia gravis (TAMG) is one of the subtypes of myasthenia gravis with autoantibodies against the acetylcholine receptor (AChR‐Ab). We analyzed the clinical features of our cohort of TAMG patients and the changes in AChR‐Ab titer before and after thymectomy in order to identify factors predicting thymoma relapses.

Methods

We retrospectively assessed: age of MG onset, MG clinical status according to MGFA (Myasthenia Gravis Foundation of America), epoch of thymectomy, post‐thymectomy status, oncological features and surgical approach. AChR‐Ab dosages were measured both before and after thymectomy. Linear regression models were applied to identify clinical determinants of AChR‐Ab titers and the Cox regression model was fitted to estimate the factors associated with the risk of thymoma recurrence.

Results

The study sample included 239 MG patients, 27 of whom experienced one or more recurrences (median follow‐up time: 4.8 years). The AChR‐Ab titers decreased after first thymectomy (P < 0.001); the decrease was more pronounced in female patients (P = 0.05), in patients diagnosed with MG at an older age (P = 0.003), and in those who had lower MG stage before surgery (P = 0.02) or higher Masaoka‐Koga stage (P = 0.005). The risk of relapse was closely linked with the age of the patient, the Masaoka‐Koga stage and the surgical approach.

Conclusions

Presurgery levels of AChR‐Ab or their change after surgery were not associated with thymoma recurrence. The reduction of AChR‐Ab titers after thymectomy confirms an immunological role of thymoma in the pathogenesis of MG.

Key points

Significant findings of the study: Young MG patients with an advanced Masaoka staging score of the primary tumor who underwent thymectomy with approaches different from sternotomy and VATS should be monitored for high risk of recurrence.

What this study adds: No other study has ever investigated the changes in AChR‐Ab titers before and after thymectomy in a large cohort of TAMG patients. The reduction of AChR‐Ab titers after thymectomy suggests an immunological role of thymoma in the pathogenesis of MG.

Melatonin exerts immunoregulatory effects by balancing peripheral effector and regulatory T helper cells in myasthenia gravis

Myasthenia gravis (MG) is a prototypic organ-specific autoimmune disorder that, in most cases, is mainly mediated by antibodies against the acetylcholine receptor. Evidence implicates CD4⁺ T helper (Th) cells in the development of MG, whereas regulatory T cells (Tregs) are associated with disease resolution. Melatonin has important immunoregulatory effects in many T cell-mediated autoimmune diseases. However, there are few studies on the role of melatonin in MG. In the present study, we investigated serum melatonin levels and melatonin receptor expression in MG patients and healthy controls (HCs). We also evaluated the impact of melatonin administration on peripheral CD4⁺ Th cells and related cytokine production. Serum melatonin levels were lower in MG patients than in HCs, and MT1 expression was lower in PBMCs from MG patients than in those from HCs. Administration of melatonin significantly decreased Th1 and Th17 cell responses and proinflammatory cytokine production. Further investigation in vitro revealed that melatonin administration increased FoxP3 and IL-10 expression in CD4⁺ T cells from MG patients and enhanced the suppressive function of Tregs. These findings indicate that melatonin exerts immunoregulatory activity in MG by balancing effector and regulatory Th cell populations as well as by suppressing proinflammatory cytokine production.