Against Acetylcholine Receptor Research Articles

Therapeutic challenges and unmet needs in the management of myasthenia gravis: an Italian expert opinion.

Myasthenia gravis (MG) is a rare, autoimmune, neurological disorder. Most MG patients have autoantibodies against acetylcholine receptors (AChRs). Some have autoantibodies against muscle-specific tyrosine kinase (MuSK) or lipoprotein-receptor-related protein 4 (LRP4), and some are seronegative. Standard of care, which includes anti-cholinesterase drugs, thymectomy, corticosteroids (CS), and off-label use of non-steroidal immunosuppressive drugs (NSISTs), is bounded by potential side effects and limited efficacy in refractory generalized MG (gMG) patients. This highlights the need for new therapeutic approaches for MG. Eculizumab, a monoclonal antibody that inhibits the complement system, has been recently approved in Italy for refractory gMG. A panel of 11 experts met to discuss unmet therapeutic needs in the acute and chronic phases of the disease, as well as the standard of care for refractory patients. Survival was emphasized as an acute phase outcome. In the chronic phase, persistent remission and early recognition of exacerbations to prevent myasthenic crisis and respiratory failure were considered crucial. Refractory patients require treatments with fast onset of action, improved tolerability, and the ability to slow disease progression and increase life expectancy. The Panel agreed that eculizumab would presumably meet the therapeutic needs of many refractory gMG patients. The panel concluded that the unmet needs of current standard of care treatments for gMG are significant. Evaluating new therapeutic options accurately is essential to find the best balance between efficacy and tolerability for each patient. Collecting real-world data on novel molecules in routine clinical practice is necessary to address unmet needs.

New treatment options for generalized myasthenia gravis

Myasthenia gravis is an autoimmune disease in which autoantibodies against the postsynaptic membrane proteins of the neuromuscular junction disrupt impulse transmission thus causing pathological muscle weakness and fatigue that worsens throughout the day. Although the disease is not yet curable, most patients can achieve complete symptom control and improved quality of life with appropriate treatment. Four treatment strategies are used in clinical practice: symptomatic, immunosuppressive, immunomodulatory, and surgical treatment, which can help control the disease but are not equally effective for all patients. Symptomatic treatment with acetylcholinesterase (AChE) inhibitors is often not effective enough, so additional treatment with immunosuppressants is indicated. These are effective, but can cause systemic side effects if taken for long periods. Even polytherapy is often not sufficient enough to treat patients with myasthenia gravis. The challenges of treating this disease are encouraging to seek alternatives. Increasing attention is being paid to antibodies against acetylcholine receptors (AChRs) and other structures of the neuromuscular junction that are important in pathogenesis of myasthenia gravis. Drugs are being developed that target specific links in the immune system to reduce the risk of systemic adverse effects. Currently, only two drugs are approved for the treatment of generalized myasthenia gravis – eculizumab and efgartigimod. Both of them are safe and effective in treating generalized myasthenia gravis with prevalent anti-AChR antibodies. Currently, 10 other drugs are clinically tested for their safety and efficacy in treating patients with myasthenia gravis. In this article, we review publications that analyze biological therapy and its novelty in the treatment of myasthenia gravis. We focus more on already approved biological drugs.

Clinical Features and Pathogenesis of Double Seronegative Myasthenia Gravis

Subjects with double seronegative myasthenia gravis (DNMG) are defined as those who are seronegative to both antibodies against acetylcholine receptor (AChR) and muscle-specific kinase (MuSK) by radioimmunoprecipitation assay (RIA). They are basically heterogeneous. But cell based assay (CBA) with clustered AChR has revealed a considerable part of DNMG are AChR antibody associated. Furthermore, information of clinical features and thymus pathology has raised a possibility that this could extend to those with undetectable antibodies by established assays whose symptoms are mild. Primary sites of antibody production are probably in the thymus in these cases. LOMG pathology is also suspected for a small part of DNMG by age onset, atrophic or age-related thymus and presence of titin antibody. In these cases, tolerance induction may be insufficient, and positive selection of autoimmune T cells such as AChR-specific T cells are promoted rather than negative selection. In addition, CBA detected MuSK antibody associated in a few cases with DNMG. Finally, some DNMG subjects have distinct clinical features with severe symptoms from those with AChR- MG and MuSK-MG in DNMG. They probably have different pathogenesis.

B-076 Comparison of Three Methods for the Detection of Antibodies Against Muscle-Specific Kinase

Abstract Background Myasthenia gravis (MG) is a neuromuscular disease characterized by skeletal muscle weakness and fatigue. These symptoms are due to a reduction in synaptic signal transduction caused by autoantibodies against post-synaptic proteins in the neuromuscular junction. Approximately 85% of patients with MG have autoantibodies against acetylcholine receptors (AChR); however, autoantibodies against muscle specific kinase (MuSK) and low-density lipoprotein receptor-related protein 4 (LRP4) may also be found in patients with MG. Detection and identification of these antibodies is important in the diagnosis and treatment of patients under evaluation for MG. MuSK, a transmembrane protein expressed on skeletal muscles, is essential to the formation and maintenance of the neuromuscular junction. Approximately 6% of MG patients have MuSK autoantibodies. Traditionally, radioimmunoprecipitation assays (RIA) have been used to detect MuSK antibodies in patient sera. However, RIA has several limitations, including safety and regulatory concerns associated with using radioactive materials and the short half-life of reagents. Alternatives to RIA, such as enzyme-linked immunosorbent assays (ELISA) and cell-based assays (CBA), do not have the same challenges. Recent studies outside of the USA suggest that cell-based assays may have equal or superior sensitivity than RIA; particularly in the detection of MuSK antibodies in patients previously diagnosed with seronegative MG (MG patients without detectable AChR or MuSK antibodies by RIA). The objective of this study was to compare the performance of two commercially available ELISA and fixed cell-based assay (f-CBA) kits to RIA for the detection of MuSK antibodies. Methods A total of 237 sera were evaluated by RIA, ELISA and/or f-CBA. These sera include 47 MuSK RIA positive sera, 55 MuSK RIA negative sera, 70 self-reported healthy control sera, and 65 sera positive for other neural antibodies associated with MG, Lambert-Eaton Myasthenic Syndrome, paraneoplastic neurologic syndromes, or autoimmune encephalitis. Results Both f-CBA and ELISA demonstrated 100% specificity for MuSK antibodies in sera from self-reported healthy controls and sera from patients positive for other antibodies. Forty-seven sera tested positive for anti-MuSK antibodies by RIA; of those 47 sera, 7 sera tested negative by ELISA and 5 tested negative by f-CBA kits while the remaining 40 were concordant between ELISA, f-CBA and RIA. The discrepancy between RIA and the commercial kits for ELISA and f-CBA was only observed in low positive sera (0.04–0.21 nmol/L ARUP RIA). Clinical information was not available for discrepant specimens. However, a review of MuSK RIA results for University of Utah patients shows that of 7 patients with an ARUP RIA result of 0.04–0.21 nmol/L, only 1 had symptoms that may possibly be consistent with MG. The remaining 6 low positive patients did not have symptoms consistent with a diagnosis of MG. This may suggest an issue with RIA specificity rather than ELISA and f-CBA sensitivity. However, further studies are needed to confirm this. Conclusion Commercially available ELISA and f-CBA kits offer viable alternatives to traditional RIA for detection of MuSK antibodies.

A multicentre, prospective, double-blind study comparing the accuracy of autoantibody diagnostic assays in myasthenia gravis: the SCREAM study

Laboratory determination of autoantibodies against acetylcholine receptor (AChR), muscle-specific kinase (MuSK) and other autoantigens have been integrated into the diagnosis of myasthenia gravis (MG). However, evidence supporting the selection of methodologies is lacking. In this prospective, multicentre cohort study, we recruited patients with suspected MG to evaluate the diagnostic accuracy of cell-based assay (CBA), radioimmunoprecipitation assay (RIPA) and enzyme-linked immunosorbent assay (ELISA) in detecting AChR and MuSK autoantibodies. This study is registered with www.clinicaltrials.gov, number NCT05219097. 2272 eligible participants were recruited, including 2043MG, 229 non-MG subjects. AChR antibodies were detected in 1478, 1310, and 1280 out of a total of 2043MG patients by CBA, RIPA, and ELISA, respectively; sensitivity, 72.3% (95% CI, 70.3-74.3), 64.1% (95% CI, 62.0-66.2), 62.7% (95% CI, 60.5-64.8); specificity, 97.8% (95% CI, 95.0-99.3), 97.8% (95% CI, 95.0-99.3), 94.8% (95% CI, 91.9-97.7). MuSK antibodies were found in 59, 50, and 54 from 2043MG patients by CBA, RIPA and ELISA, respectively; sensitivity, 2.9% (95% CI, 2.2-3.7), 2.4% (95% CI, 1.8-3.2), 2.6% (95% CI, 2.0-3.4); specificity, 100% (95% CI, 98.4-100), 100% (95% CI, 98.4-100), and 99.1% (95% CI, 96.9-99.9). The area under the curve of AChR antibodies tested by CBA was 0.858, and there were statistical differences with RIPA (0.843; p=0.03) and ELISA (0.809; p<0.0001). CBA has a higher diagnostic accuracy compared to RIPA or ELISA in detecting AChR and MuSK autoantibodies for MG diagnosis. New Terrain Biotechnology, Inc., Tianjin, China.

Frequency and Correlates of Mild Cognitive Impairment in Myasthenia Gravis

Antibodies against acetylcholine receptors (AChRs) can also target nicotinic AChRs that are present throughout the central nervous system, thus leading to cognitive dysfunctions in patients with myasthenia gravis (MG). However, the presence of cognitive impairment in MG is controversial, and the factors that may influence this risk are almost completely unknown. In this study, the frequency of mild cognitive impairment (MCI) in MG, as well as the clinical, immunological, and behavioral correlates of MCI in MG were evaluated. A total of 52 patients with MG underwent a comprehensive assessment including motor and functional scales, serological testing, and neuropsychological and behavioral evaluation. The frequency of MCI was 53.8%, and the most impaired cognitive domains were, in order, visuoconstructive/visuospatial skills, memory, and attention. After multivariate analysis, only pyridostigmine use was inversely associated with the presence of MCI, while a trend toward a positive association between MCI and disease severity and arms/legs hyposthenia was found. Correlation analyses showed that daily doses of prednisone and azathioprine significantly correlated with depressive symptomatology, while disease severity significantly correlated with depressive symptomatology and sleep disturbance. The presence of MCI is rather frequent in MG and is characterized by multidomain amnestic impairment. Such preliminary data need further confirmation on larger case series.

Invigorating spleen, replenishing qi and tonifying kidney method treatment of traditional Chinese medicine for myasthenia gravis: A protocol for systematic review and meta-analysis

Myasthenia gravis (MG) is an autoimmune disease related to the production of autoantibodies. It is mediated by antibodies against acetylcholine receptor (AChR), muscle specific kinase (MuSK) or other AChR related proteins in the postsynaptic muscle membrane, which interfere with the transmission of signals at the neuromuscular junction, resulting in clinical symptoms of skeletal muscle weakness and fatigue, leading to the occurrence and development of MG. At present, the incidence rate of Mg is increasing year by year. At present, the method of invigorating spleen, replenishing qi and tonifying kidney in traditional Chinese medicine has been widely used in the clinical treatment of MG, and the effect is good. The purpose of this study was to systematically evaluate the efficacy and safety of the method of invigorating the spleen, supplementing qi and tonifying the kidney in the treatment of MG. We will search from the following eight databases: PubMed, Cochrane Library, EMBASE, Web of Science, CNKI, Sinomed, Wanfang, and Vip. All randomized controlled trial (RCT) literature has been searched and classified since the establishment of the database to date. In this study, two researchers independently screened and evaluated the quality of the retrieved literature. Cochrane risk bias assessment tool was used to evaluate the risk of bias. The meta-analysis uses RevMan 5.3 software provided by Cochrane Collaboration Network for meta analysis. This study compared the main outcome indicators: clinical response rate, recurrence rate, incidence of adverse reactions, quantitative myasthenia gravis score (QMG). Secondary outcomes were clinical absolute score, quality of life score (QOL), levels of inflammatory factors such as IL-6, IL-10, and serum acetylcholine receptor antibody (AChR-Ab) levels. The purpose of this study was to evaluate the efficacy and safety of the method of invigorating the spleen, supplementing qi and tonifying the kidney in treating MG, and to provide evidence based medicine.

Clinical picture and treatment of myasthenia gravis in the adult population

Introduction and purpose: Myasthenia gravis (MG, myasthenia gravis ) is a classic example of an autoimmune disease caused by antibodies against acetylcholine receptors ( AChR) , muscle-specific kinase (MuSK) or other AChR-related proteins in the postsynaptic muscle membrane leading to characteristic muscle weakness.&#x0D; Description of the state of knowledge: It is not fully known why the body begins to produce antibodies that act against its own acetylcholine receptors. The main role in producing these antibodies is played by the thymus gland, a gland located in the chest. The thymus gland is normally present in children, while it atrophies in adults. In about 60% of myasthenia gravis patients, however, it is present (we say they have a persistent thymus), and 15% of patients have a thymic neoplasm called a thymoma.&#x0D; Summary: Myasthenia gravis is the most common neuromuscular junction disorder. Myasthenia gravis is a rare disease that involves muscle weakness of the eyes, pharynx, larynx, respiratory muscles and limbs. Clinical manifestations vary depending on the type of autoantibody and the presence of thymoma. The diagnosis of the disease should be confirmed by electrodiagnostic and laboratory tests in addition to the typical symptoms. Myasthenia gravis can manifest at any age, both in men ( peak incidence 50-60 years of age) and women ( peak incidence 20-30 years of age). Muscle fatigue intensifies after any exercise, even small ones. The patient feels best in the morning hours, right after waking up. As time passes, the symptoms of muscle fatigue intensify and the patient becomes less and less fit. For this reason, patients should rest frequently.

P.97 Clinical differences between ocular and generalized myasthenia gravis

Myasthenia gravis (MG) is an autoimmune disease that leads to activity induced weakness in skeletal muscle, which in most cases, are caused by autoantibodies against acetylcholine receptors (AChR). Some patients only have ocular symptoms throughout life (ptosis and diplodia) whereas others have more generalized symptoms such as weakness in extremities and the neck muscles, dysphagia and dysarthria. Not many studies have evaluated whether differences regarding demographics and phenotype separate the two groups of MG patients. Such differences may have consequences for the diagnostic process and management of the disease. Data are collected from an ongoing, retrospective chart review, in which we aim to collect data on 400 patients. Characteristics such as age, gender composition, thymoma status, disease onset and evolution, antibody profile, result of neurophysiological examination, medication, treatment response and satisfaction level are evaluated. By aiming this knowledge, we hope to understand the pathophysiology even better, optimize guidelines and patient satisfaction level. Preliminary results from the first 300 patients suggest that there is a larger time delay from symptom onset until diagnose in the purely ocular group. 21,4% of the ocular patients are diagnosed within two months, where it is 27,8% in the generalized group (p-value=0,57). The average number of MG drugs used to treat the ocular patients are 2,3 drugs compared with 3,2 drugs used to treat the generalized patients (p-value=0,0001). The gender composition is 52,6% women in the ocular group versus 52,7% in the generalized group. The results suggest that it is more difficult to diagnose the ocular patients, but insignificantly less complicated to treat this group. The gender composition seems to be equal in the two groups. More data will be presented in the poster.

A bioassay for neuromuscular junction-restricted complement activation by myasthenia gravis acetylcholine receptor antibodies

BackgroundMyasthenia gravis (MG) is an autoimmune neuromuscular disorder hallmarked by fluctuating fatigable muscle weakness. Most patients have autoantibodies against acetylcholine receptors (AChRs) at the neuromuscular junction (NMJ). These are thought to have three possible pathogenic mode-of-actions: 1) cross-linking and endocytosis of AChRs, 2) direct block of AChRs and 3) complement activation. The relative contributions of these mechanisms to synaptic block and muscle weakness of individual patients cannot be determined. It likely varies between patients and perhaps also with disease course, depending on the nature of the circulating AChR antibodies. New methodWe developed a new bioassay which specifically enables functional characterization and quantification of complement-mediated synaptic damage at NMJs, without interference of the other pathogenic mechanisms. To this end, we pre-incubated mouse hemi-diaphragm muscle-nerve preparations with mAb35-hG1, a humanized rat AChR monoclonal and subsequently exposed the preparation to normal human serum as a complement source. NMJ-restricted effects were studied. ResultsClearly NMJ-restricted damage occurred. With immunohistology we showed complement deposition at NMJs, and synaptic electrophysiological measurements demonstrated transmission block. In whole-muscle contraction experiments we quantified the effect and characterized its onset and progression during the incubation with normal human serum. Comparison with existing methodsWith this new assay the complement-mediated component of myasthenic NMJ pathology can be studied separately. ConclusionsOur assay will be of importance in detailed mechanistic studies of local complement activation at NMJs, investigations of new complement inhibitors, and laboratory pre-screening of therapeutic efficacy for individual MG patients to optimize care with clinically approved complement inhibitors.

Laboratory Investigation of Hybrid IgG4 k/λ in MuSK Positive Myasthenia Gravis

Myasthenia gravis with antibodies (Abs) against the muscle-specific tyrosine kinase (MuSK) is a rare autoimmune disorder (AD) of the neuromuscular junction (NMJ) and represents a prototype of AD with proven IgG4-mediated pathogenicity. Thanks to the mechanism of Fab-arm exchange (FAE) occurring in vivo, resulting MuSK IgG4 k/λ Abs increase their interference on NMJ and pathogenicity. The characterization of hybrid MuSK IgG4 as a biomarker for MG management is poorly investigated. Here, we evaluated total IgG4, hybrid IgG4 k/λ, and the hybrid/total ratio in 14 MuSK-MG sera in comparison with 24 from MG with Abs against acetylcholine receptor (AChR) that represents the not IgG4-mediated MG form. In both subtypes of MG, we found that the hybrid/total ratio reflects distribution reported in normal individuals; instead, when we correlated the hybrid/total ratio with specific immune-reactivity we found a positive correlation only with anti-MuSK titer, with a progressive increase of hybrid/total mean values with increasing disease severity, indirectly confirming that most part of hybrid IgG4 molecules are engaged in the anti-MuSK pathogenetic immune-reactivity. Further analysis is necessary to strengthen the significance of this less unknown biomarker, but we retain it is full of a diagnostic-prognostic powerful potential for the management of MuSK-MG.

Efgartigimod: PLEX in a Bottle — A Quick Fix for Myasthenia Gravis

Myasthenia gravis (MG) is an autoimmune disorder caused by immunoglobulin G (IgG autoantibodies directed against acetylcholine receptors (AChRs) or,

New diagnosis of myasthenia gravis presenting as myasthenic crisis after radical thymectomy: a case report

: Myasthenia gravis (MG) is a well-known paraneoplastic syndrome associated with thymomas. It occurs secondary to the production of autoantibodies against acetylcholine receptors (AChR). This results in the reduced delivery of action potentials that generate muscular contractions. In its most extreme form, MG can present as a crisis resulting in respiratory failure requiring invasive ventilatory support. There are several known risk factors for patients with known MG to develop a post-operative crisis after thymectomy. It is recommended that patients diagnosed with thymoma be evaluated for MG prior to resection. However, most guidelines do not make any recommendations regarding screening with AChR antibody tests if there are no signs or symptoms of MG. In this case report, we present a patient with an incidental finding of a large anterior mediastinal thymoma with no signs or symptoms of MG. The patient subsequently develops bulbar symptoms and dyspnea necessitating readmission to hospital 2 weeks after surgery. This eventually culminated in cardiorespiratory arrest. This was confirmed to be secondary to a myasthenic crisis via AChR autoantibody testing. The patient was treated with intravenous immunoglobulin (IVIG), pyridostigmine and prednisone with good effect. The onset of myasthenic crisis after a surgical insult in known MG patients has been well documented. However, the development of myasthenic crisis in an asymptomatic patient with no history of MG has not previously been shown. This case report illustrates the need for more sensitive screening tools to detect MG in patients with thymoma. The routine use of AChR autoantibody testing as a screening tool in patients with thymoma even when asymptomatic and/or deemed low risk may help clinicians better prepare for possible MG flairs. Furthermore, surgeons should have a low threshold to suspect MG in patients after thymectomy regardless of time elapsed since surgery.

Drugs That Induce or Cause Deterioration of Myasthenia Gravis: An Update

Myasthenia gravis (MG) is an autoimmune neuromuscular disorder which is characterized by presence of antibodies against acetylcholine receptors (AChRs) or other proteins of the postsynaptic membrane resulting in damage to postsynaptic membrane, decreased number of AChRs or blocking of the receptors by autoantibodies. A number of drugs such as immune checkpoint inhibitors, penicillamine, tyrosine kinase inhibitors and interferons may induce de novo MG by altering the immune homeostasis mechanisms which prevent emergence of autoimmune diseases such as MG. Other drugs, especially certain antibiotics, antiarrhythmics, anesthetics and neuromuscular blockers, have deleterious effects on neuromuscular transmission, resulting in increased weakness in MG or MG-like symptoms in patients who do not have MG, with the latter usually being under medical circumstances such as kidney failure. This review summarizes the drugs which can cause de novo MG, MG exacerbation or MG-like symptoms in nonmyasthenic patients.

The role of innate immunity in myasthenia gravis.

Myasthenia gravis (MG) is a T cell-driven, B cell-mediated and autoantibody-dependent autoimmune disorder against neuromuscular junctions (NMJ). Accumulated evidence has emerged regarding the role of innate immunity in the pathogenesis of MG. In this review, we proposed two hypothesis underlying the pathological mechanism. In the context of gene predisposition, on the one hand, Toll-like receptors (TLRs) pathways were initiated by viral infection in the thymus with MG to generate chemokines and pro-inflammatory cytokines such as Type I interferon (IFN), which facilitate the thymus to function as a tertiary lymphoid organ (TLO). On the another hand, the antibodies against acetylcholine receptors (AChR) generated by thymus then activated the classical pathways on thymus and neuromuscular junction (NMJ). Futher, we also highlight the role of innate immune cells in the pathogenic response. Finally, we provide some future perspectives in developing new therapeutic approaches particularly targeting the innate immunity for MG.

Effect of Grilled Nux Vomica on Differential RNA Expression Profile of Gastrocnemius Muscle and Toll‑Like Receptor 4 (TLR-4)/Nuclear Factor kappa B (NF-κB) Signaling in Experimental Autoimmune Myasthenia Gravis Rats.

BackgroundMyasthenia gravis (MG) is a progressive autoimmune disorder caused by the production of antibodies directed against acetylcholine receptors (AChRs), resulting in muscle weakness and fatigue. This study aimed to explore the effect and mechanism of grilled nux vomica (GNV) in experimental autoimmune myasthenia gravis (EAMG) rats.Material/MethodsRat 97–116 peptides were used to mediate disease in the EAMG model in SPF female Lewis rats. The treatment groups received grilled nux vomica (75 mg/kg, 150 mg/kg, and 225 mg/kg). The autoantibody and inflammatory cytokines levels were measured by enzyme-linked immunosorbent assay (ELISA). RNA profiling was performed on high-dose and model group rats. Profiling results and TLR-4/NF-κB signaling were validated by q-PCR and Western blot analysis.ResultsThe results showed that GNV could attenuate the symptoms of EAMG rats. There was a decreased level of AChR-ab, IFN-γ, TNF-α, IL-2, IL-4, and IL-17 levels, and an increased level of TGF-β1. In total, 235 differentially expressed genes (DEGs), consisting of 175 upregulated DEGs and 60 downregulated DEGs, were identified. Functional annotation demonstrated that DEGs were largely associated with leukocyte cell–cell adhesion, NF-kappa B signaling pathway, muscle contraction, and cardiac muscle contraction pathway. Rac2, Itgb2, Lcp2, Myl3, and Tnni1 were considered as hub genes with a higher degree value in the protein–protein interaction (PPI) network. The q-PCR and Western blot results of hub genes were consistent with RNA profiles. GNV treatment also significantly reduced the TLR-4 and NF-κB p65 protein expression in EAMG rats.ConclusionsThese results indicate that grilled nux vomica ameliorates EAMG by depressing the TLR-4/NF-κB signaling pathway, and hub genes may serve as potential targets for MG treatment.

Myasthenia gravis

Myasthenia gravis (MG) is an autoimmune disorder caused by antibodies against acetylcholine receptors (AChR) or other structural proteins of the neuromuscular junction. This diminishes cholinergic transmission, thus leading to exercise-induced fatigue and sometimes manifest muscle weakness, including the bulbar and ocular musculature. Whereas ocular MG is as a rule initially symptomatically treated with acetylcholine esterase inhibitors, generalized MG requires long-term immunosuppression. The thymus plays aparticular role in the pathophysiology of AChR antibody-positive MG, which can also manifest as aparaneoplastic disorder in the context of athymoma. This article reviews the basic and advanced treatment options of the different disease subtypes including plasma exchange and immunoglobulins for treatment in a myasthenic crisis. Recently, clinical approval of eculizumab, acomplement inhibitor, enriched the pharmacological armamentarium for AChR antibody-positive MG patients not appropriately responding to immunosuppression alone.

Recent advances in understanding and managing myasthenia gravis.

Autoimmune myasthenia gravis (MG) is a neuromuscular junction disorder marked clinically by fatigable muscle weakness and serologically by the presence of autoantibodies against acetylcholine receptors (AChRs), muscle-specific kinase (MuSK), or lipoprotein-related protein 4 (LPR4). Over the past few decades, the mortality of patients with MG has seen a dramatic decline secondary to evolving interventions in critical care and medical management. In the past 2 to 3 years, there have been several changes in standard of care for the treatment of MG. These changes include confirmation of the benefit of thymectomy versus medical management alone in AChR patients and a new US Food and Drug Administration-approved medication for refractory MG. There are also several exciting new prospective drugs in the pipeline, which are in different stages of clinical trial testing.

Maternal myasthenia gravis represents a risk for the child through autoantibody transfer, immunosuppressive therapy and genetic influence.

Females with myasthenia gravis (MG) worry about their disease having negative consequences for their children. Autoimmune disease mechanisms, treatment and heredity could all have an impact on the child. This is a subject review where Web of Science was searched for relevant keywords and combinations. Controlled and prospective studies were included, and also results from selected and unselected patient cohorts, guidelines, consensus papers and reviews. Neonatal MG with temporary muscle weakness occurs in 10% of newborn babies where the mother has MG, due to transplacental transfer of antibodies against acetylcholine receptor (AChR), muscle-specific kinase (MuSK) or lipoprotein receptor-related protein 4 (LRP4). Arthrogryposis and fetal AChR inactivation syndrome with contractures and permanent myopathy are rare events caused by mother's antibodies against fetal type AChR. The MG drugs pyridostigmine, prednisolone and azathioprine are regarded as safe during pregnancy and breastfeeding. Methotrexate, mycophenolate mofetil and cyclophosphamide are teratogenic. Mother's MG implies at least a 10-fold increased risk for MG and other autoimmune diseases in the child. MG females should receive specific information about pregnancy and giving birth. First-line MG treatments should usually be continued during pregnancy. Intravenous immunoglobulin and plasma exchange represent safe treatments for exacerbations. Neonatal MG risk means that MG women should give birth at hospitals experienced in neonatal intensive care. Neonatal MG needs supportive care, rarely also acetylcholine esterase inhibition or intravenous immunoglobulin. Women with MG should be supported in their wish to have children.

Myasthenia gravis: current status of antibody diagnostics and aspects on refractory myasthenia gravis

Acquired myasthenia gravis (MG) is an autoimmune disease that leads to fluctuating muscle weakness and fatigue, caused by circulating antibodies against different structures of the neuromuscular junction. In most patients, antibodies against acetylcholine receptor (AChR) can be detected. In a smaller proportion of patients with and without AChR antibodies, antibodies to muscle-specific kinase (MuSK), or related proteins such as agrin, cortactin and low-density lipoprotein receptor-related protein 4 (LRP4), are present. With current therapy, most patients achieve a stable condition with good quality of life and normal life expectancy. Nevertheless, 10 to 15 % of patients fail to respond ad equately to current therapies and are defined as refractory myasthenia gravis. Their clinical course is characterized by recurrent episodes of severe, acute deterioration, which sometimes appear life threatening. This article gives an overview of the current state of myasthenic antibody diagnostics and recommended treatment of refractory myasthenia gravis.