Long-term cyclosporine treatment in a group of severe myasthenia gravis patients

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.

Current Treatment of Myasthenia Gravis

Myasthenia gravis (MG) is the most extensively studied antibody-mediated disease in humans. Substantial progress has been made in the treatment of MG in the last century, resulting in a change of its natural course from a disease with poor prognosis with a high mortality rate in the early 20th century to a treatable condition with a large proportion of patients attaining very good disease control. This review summarizes the current treatment options for MG, including non-immunosuppressive and immunosuppressive treatments, as well as thymectomy and targeted immunomodulatory drugs.

Update in immunosuppressive therapy of myasthenia gravis

Myasthenia gravis (MG) is an autoimmune disease of the neuromuscular junction. Immunosuppressive treatments are part of the therapeutic armamentarium in MG. Long-term systemic steroid administration carry considerable risks and adverse events. Consequently, steroid-free immunosuppressive therapy is necessary to reduce the dose or discontinue steroids. First immunosuppressive drug trials in MG were performed in the mid-60s using standard and nonspecific immunosuppression. Since then, only few randomized controlled clinical trials were conducted in MG and assesed drug efficacy in terms of its steroid-sparing capacity and the ability to reduce myasthenic signs and symptoms. Treatment strategy in MG is quite challenging, mainly due to the disease heterogeneity in terms of clinical presentation, immunopathogenesis and drug response. To solve this dilemma, emerging treatment are based on biological drugs and use new targets of the immune pathway.

Reappraisal of Oral Steroid Therapy for Myasthenia Gravis

Treatment with oral corticosteroids at high doses with an escalation and de-escalation schedule is effective against myasthena gravis (MG). In fact, the use of corticosteroids has led to a reduction in mortality to below 10% after the 1960s. However, long-term use of oral steroids above a certain dosage level is known to cause a number of problems. In 2014, the Japanese clinical guidelines for MG proposed that the first goal in MG treatment (treatment target) should be set at minimal manifestations (MM) with oral prednisolone (PSL) 5 mg/day or below, and that treatment strategies should strive to attain this level as rapidly as possible. In 2015, a multicenter, cross-sectional study revealed that higher PSL dose and longer PSL treatment do not ensure better outcome. In the absence of good response, the PSL dose should be decreased by combining with modalities such as plasma exchange/plasmapheresis and intravenous immunoglobulin (fast-acting treatments). In 2018, we conducted a multicenter, cross-sectional study in a large population of Japanese patients with generalized MG, aiming to elucidate the correlation between oral PSL regimens and achievement of treatment goals. The ORs for low vs. high dose to achieve treatment goals at 1, 2, and 3 years were 10.4, 2.75, and 1.86, respectively, whereas the corresponding ORs for low vs. medium dose were 13.4, 3.99, and 4.92. Early combination with fast-acting therapy (OR 2.19 at 2 years, 2.11 at 3 years) or combination with calcineurin inhibitors (OR 2.09 at 2 years, 2.36 at 3 years) were also positively associated with achieving treatment goals. These results indicate that early combination of low-dose PSL regimens with other therapies is the key for early achievement of treatment goals in generalized MG. However, even with this regimen, ~35% of patients did not achieve the treatment target after 3 years. These results suggest the limitation of the current oral corticosteroid therapy. We need to develop new treatment options to increase the rate of satisfactory outcome.

Risiken und Chancen von Immuntherapien in Zeiten der Coronavirus-2019-Pandemie

Immuntherapien stellen die essenzielle Grundlage der Behandlung von neuroinflammatorischen Erkrankungen dar. In Zeiten der Coronavirus-2019 (COVID-19)-Pandemie ergibt sich im klinischen Alltag jedoch zunehmend die Frage, ob eine Immuntherapie bei neurologischen Patienten aufgrund des potenziellen Infektionsrisikos eingeleitet, intensiviert, pausiert oder gar beendet werden sollte. Unsicherheit besteht v. a. deshalb, weil verschiedene nationale und internationale Fachgesellschaften diesbezüglich unterschiedliche Empfehlungen veröffentlichten. In diesem Artikel soll ein Überblick über die Wirkmechanismen von Immuntherapien und den daraus abzuleitenden Infektionsrisiken in Bezug auf COVID-19 (durch den Coronavirus verursachte Erkrankung) gegeben werden. Potenzielle Chancen und vorteilhafte Effekte einzelner Substrate in der Akuttherapie von COVID-19 werden diskutiert.

Merits and culprits of immunotherapies for neurological diseases in times of COVID-19

Immunosuppression and immunomodulation are valuable therapeutic approaches for managing neuroimmunological diseases. In times of the Coronavirus disease 2019 (COVID-19) pandemic, clinicians must deal with the question of whether immunotherapy should currently be initiated or discontinued in neurological patients. Uncertainty exists especially because different national medical associations publish different recommendations on the extent to which immunotherapies must be continued, monitored, or possibly switched during the current pandemic. Based on the most recently available data both about the novel coronavirus and the approved immunotherapies for neurological diseases, we provide an updated overview that includes current treatment strategies and the associated COVID-19 risk, but also the potential of immunotherapies to treat COVID-19.

Newer Immunotherapies for the Treatment of Acute Neuromuscular Disease in the Critical Care Unit

OPINION STATEMENT

PURPOSE OF REVIEW: In this review, we discuss current treatment options for commonly encountered neuromuscular disorders in intensive care units. We will discuss epidemiology, pathophysiology, and acute and chronic treatment options for myasthenia gravis, Guillain-Barré syndrome, West Nile virus, Botulism, and amyotrophic lateral sclerosis.

RECENT FINDINGS

Eculizumab is the newest immunomodulator therapy approved by the Food and Drug Administration in treatment of myasthenia gravis, shown to improve long-term functional outcomes. Edaravone is the newest therapy in management of amyotrophic lateral sclerosis, shown to slow functional deterioration. Efgartigimod showed great promise in a phase 2 safety and efficacy trial in the treatment of stable generalized myasthenia gravis. Eculizumab was found to be safe in a small phase 2 trial for use in Guillain-Barré syndrome. Currently, therapies such as plasma exchange, intravenous immunoglobulins, and steroids remain the mainstay of treatment in the ICU for many neuromuscular disorders. While there are some newer immunotherapies available, few have been studied in the acute setting. However, with the advent of new immunotherapies and biologics, changes in these approaches may be on the horizon.

Maintenance immunosuppression in myasthenia gravis, an update

Therapies for myasthenia gravis (MG) include symptomatic and immunosuppressive/immunomodulatory treatment. Options for immunosuppression include corticosteroids, azathioprine, mycophenolate mofetil, cyclosporine, tacrolimus, methotrexate, rituximab, cyclophosphamide, eculizumab, intravenous immunoglobulin, subcutaneous immunoglobulin, plasmapheresis, and thymectomy. The practical aspects of long-term immunosuppressive therapy in MG are critically reviewed in this article. Application of one or more of these specific therapies is guided based on known efficacy, adverse effect profile, particular disease subtype and severity, and patient co-morbidities.

Myasthenia gravis: an update for the clinician

This paper provides a thorough overview of the current advances in diagnosis and therapy of myasthenia gravis (MG). Nowadays the term 'myasthenia gravis' includes heterogeneous autoimmune diseases, with a postsynaptic defect of neuromuscular transmission as the common feature. Myasthenia gravis should be classified according to the antibody specificity [acetylcholine, muscle-specific receptor tyrosine kinase (MuSK), low-density lipoprotein receptor-related protein 4 (LRP4), seronegative], thymus histology (thymitis, thymoma, atrophy), age at onset (in children; aged less than or more than 50 years) and type of course (ocular or generalized). With optimal treatment, the prognosis is good in terms of daily functions, quality of life and survival. Symptomatic treatment with acetylcholine esterase inhibition is usually combined with immunosuppression. Azathioprine still remains the first choice for long-term immunosuppressive therapy. Alternative immunosuppressive options to azathioprine include cyclosporin, cyclophosphamide, methotrexate, mycophenolate mofetil and tacrolimus. Rituximab is a promising new drug for severe generalized MG. Emerging therapy options include belimumab, eculizumab and the granulocyte- macrophage colony-stimulating factor. One pilot study on etanercept has given disappointing results. For decades, thymectomy has been performed in younger adults to improve non-paraneoplastic MG. However, controlled prospective studies on the suspected benefit of this surgical procedure are still lacking. In acute exacerbations, including myasthenic crisis, intravenous immunoglobulin, plasmapheresis and immunoadsorption are similarly effective.

Overview of myasthenia gravis

Myasthenia gravis is an antibody-mediated disorder of neuromuscular transmission that is characterized by weakness and fatigue of voluntary muscles. Weakness may be ocular, bulbar, or generalized. Diagnostic evaluation of patients consists of bedside assessment, antibody testing, and electrophysiologic studies. Various therapeutic options are available, which consist of anticholinesterase inhibitors for symptomatic management, immunosuppressive agents as maintenance therapy, and thymectomy. Plasmapheresis and intravenous immunoglobulin are used in patients in crisis or those with rapidly worsening or refractory symptoms. In our article, we elaborate on key aspects of the epidemiology, pathogenesis, diagnostic evaluation, and therapeutic options for patients with myasthenia gravis.

Preoperative high-dose steroid has long-term beneficial effects for myasthenia gravis

Previous studies addressing preoperative steroid treatment have revealed that control of myasthenia gravis (MG) with steroids prior to surgery appeared to stabilize postoperative status. The purpose of our study was to clarify the clinical benefits of the preoperative programmed high-dose steroid treatment on the long-term outcomes of MG patients. We retrospectively reviewed the records of 171 MG patients who were followed up after undergoing thymectomy in our hospital between 1988 and 2006. One hundred and thirteen patients in the programmed treatment group had received preoperative steroid treatment, while 58 patients received no steroid treatment during the preoperative period. Clinical remission, which was defined as the achievement of the modified pharmacologic remission (PR) for at least 1 year, and clinical benefits were compared between the two groups. With regard to the remission after thymectomy, Kaplan-Meier life-table curves for patients in the preoperative steroid treatment group versus those for patients in the no steroid preoperative treatment group revealed a significantly higher probability of the PR in the preoperative steroid treatment group (log-rank test, P < 0.01). This study might be the first, as per our knowledge, to indicate that preoperative programmed high-dose steroid treatment has long-term beneficial effects for MG patients.

Treatment of myasthenia gravis based on its immunopathogenesis

The prognosis of myasthenia gravis (MG) has improved dramatically due to advances in critical-care medicine and symptomatic treatments. Its immunopathogenesis is fundamentally a T-cell-dependent autoimmune process resulting from loss of tolerance toward self-antigens in the thymus. Thymectomy is based on this immunological background. For MG patients who are inadequately controlled with sufficient symptomatic treatment or fail to achieve remission after thymectomy, remission is usually achieved through the addition of other immunotherapies. These immunotherapies can be classified into two groups: rapid induction and long-term maintenance. Rapid induction therapy includes intravenous immunoglobulin (IVIg) and plasma exchange (PE). These produce improvement within a few days after initiation, and so are useful for acute exacerbation including myasthenic crisis or in the perioperative period. High-dose prednisone has been more universally preferred for remission induction, but it acts more slowly than IVIg and PE, commonly only after a delay of several weeks. Slow tapering of steroids after a high-dose pulse offers a method of maintaining the state of remission. However, because of significant side effects, other immunosuppressants (ISs) are frequently added as "steroid-sparing agents". The currently available ISs exert their immunosuppressive effects by three mechanisms: 1) blocking the synthesis of DNA and RNA, 2) inhibiting T-cell activation and 3) depleting the B-cell population. In addition, newer drugs including antisense molecule, tumor necrosis factor alpha receptor blocker and complement inhibitors are currently under investigation to confirm their effectiveness. Until now, the treatment of MG has been based primarily on experience rather than gold-standard evidence from randomized controlled trials. It is hoped that well-organized studies and newer experimental trials will lead to improved treatments.

Autoimmune neuromuscular disorders in childhood

OPINION STATEMENT

Autoimmune neuromuscular disorders in childhood include Guillain-Barré syndrome and its variants, chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), juvenile myasthenia gravis (JMG), and juvenile dermatomyositis (JDM), along with other disorders rarely seen in childhood. In general, these diseases have not been studied as extensively as they have been in adults. Thus, treatment protocols for these diseases in pediatrics are often based on adult practice, but despite the similarities in disease processes, the most widely used treatments have different effects in children. For example, some of the side effects of chronic steroid use, including linear growth deceleration, bone demineralization, and chronic weight issues, are more consequential in children than in adults. Although steroids remain a cornerstone of therapy in JDM and are useful in many cases of CIDP and JMG, other immunomodulatory therapies with similar efficacy may be used more frequently in some children to avoid these long-term sequelae. Steroids are less expensive than most other therapies, but chronic steroid therapy in childhood may lead to significant and costly medical complications. Another example is plasma exchange. This treatment modality presents challenges in pediatrics, as younger children require central venous access for this therapy. However, in older children and adolescents, plasma exchange is often feasible via peripheral venous access, making this treatment more accessible than might be expected in this age group. Intravenous immunoglobulin also is beneficial in several of these disorders, but its high cost may present barriers to its use in the future. Newer steroid-sparing immunomodulatory agents, such as azathioprine, tacrolimus, mycophenolate mofetil, and rituximab, have not been studied extensively in children. They show promising results from case reports and retrospective cohort studies, but there is a need for comparative studies looking at their relative efficacy, tolerability, and long-term adverse effects (including secondary malignancy) in children.

Current and emerging treatments for the management of myasthenia gravis

Myasthenia gravis is an autoimmune neuromuscular disorder. There are several treatment options, including symptomatic treatment (acetylcholinesterase inhibitors), short-term immunosuppression (corticosteroids), long-term immunosuppression (azathioprine, cyclosporine, cyclophosphamide, methotrexate, mycophenolate mofetil, rituximab, tacrolimus), rapid acting short-term immunomodulation (intravenous immunoglobulin, plasma exchange), and long-term immunomodulation (thymectomy). This review explores in detail these different treatment options. Potential future treatments are also discussed.

Cyclosporin A--a review on fermentative production, downstream processing and pharmacological applications

In present times, the immunosuppressants have gained considerable importance in the world market. Cyclosporin A (CyA) is a cyclic undecapeptide with a variety of biological activities including immunosuppressive, anti-inflammatory, antifungal and antiparasitic properties. CyA is produced by various types of fermentation techniques using Tolypocladium inflatum. In the present review, we discuss the biosynthetic pathway, fermentative production, downstream processing and pharmacological activities of CyA.

Long-term follow up of thymus in patients with myasthenia gravis

We examined transversely the thymus of 33 myasthenia gravis (MG) patients followed up for more than 5 years and found three thymomas. One was found 21 years after thymoma resection (Masaoka I, WHO Type B2 thymoma) and extended thymectomy. The other two were non-thymomatous at onset, and they were not treated with extended thymectomy. Therapeutic guidelines should mention the importance of follow-up in MG thymus.

Guidelines for treatment of autoimmune neuromuscular transmission disorders

BACKGROUND

Important progress has been made in our understanding of the autoimmune neuromuscular transmission (NMT) disorders; myasthenia gravis (MG), Lambert-Eaton myasthenic syndrome (LEMS) and neuromyotonia (Isaacs' syndrome).

METHODS

To prepare consensus guidelines for the treatment of the autoimmune NMT disorders, references retrieved from MEDLINE, EMBASE and the Cochrane Library were considered and statements prepared and agreed on by disease experts.

CONCLUSIONS

Anticholinesterase drugs should be given first in the management of MG, but with some caution in patients with MuSK antibodies (good practice point). Plasma exchange is recommended in severe cases to induce remission and in preparation for surgery (recommendation level B). IvIg and plasma exchange are effective for the treatment of MG exacerbations (recommendation level A). For patients with non-thymomatous MG, thymectomy is recommended as an option to increase the probability of remission or improvement (recommendation level B). Once thymoma is diagnosed, thymectomy is indicated irrespective of MG severity (recommendation level A). Oral corticosteroids are first choice drugs when immunosuppressive drugs are necessary (good practice point). When long-term immunosuppression is necessary, azathioprine is recommended to allow tapering the steroids to the lowest possible dose whilst maintaining azathioprine (recommendation level A). 3,4-Diaminopyridine is recommended as symptomatic treatment and IvIG has a positive short-term effect in LEMS (good practice point). Neuromyotonia patients should be treated with an antiepileptic drug that reduces peripheral nerve hyperexcitability (good practice point). For paraneoplastic LEMS and neuromyotonia optimal treatment of the underlying tumour is essential (good practice point). Immunosuppressive treatment of LEMS and neuromyotonia should be similar to MG (good practice point).

Factors associated with response to calcineurin inhibitors in myasthenia gravis

The objective was to assess which clinical factors of patients with myasthenia gravis (MG) are associated with responsiveness to calcineurin inhibitors (CNIs, cyclosporine and tacrolimus). We retrospectively analyzed the 6-month effects of CNIs in 62 MG patients. We excluded the influence of other immune treatments and determined factors associated with response to CNIs. The frequency of patients who achieved neither a > or =3-point reduction in quantitative MG score nor a > or =25% reduction in daily dose of prednisolone (poor responders) reached 35.5% (22/62) and 64.5% (40/62), respectively, compared with patients who achieved at least one of these improvements (responders). Neither dose nor blood concentration of CNIs differed between groups. Multivariate logistic regression analysis revealed time since onset of disease [odds ratio (OR) = 0.85, P = 0.005] and presence of thymoma (OR = 5.56, P = 0.05) as clinical factors that predict response to CNIs. As for MG-related autoantibody status, an autoantibody against a voltage-gated potassium channel, Kv1.4, was associated with response (OR = 9.01, P = 0.04) and showed a correlation with the presence of thymoma (P < 0.01). In MG, the early stages of disease and thymoma-associated MG are responsive to treatment with CNIs.

Clinical efficacy and cytokine network-modulating effects of tacrolimus in myasthenia gravis

To clarify the long-term efficacy, safety and the cytokine network-modulating effects of tacrolimus in myasthenia gravis, medical records of 86 newly diagnosed consecutive patients and nine steroid-dependent patients were retrospectively reviewed, and peripheral blood mononuclear cells (PBMC) were cultured for the cytokine profile. Steroid reduction effects were observed by using tacrolimus, and no serious adverse effects were observed. The culture study showed reduced IL-12, IL-17, IFN-gamma, GM-CSF, TNF-alpha and MIP-1beta, and elevated IL-10 in the PBMC from patients who received tacrolimus, which suggests inhibition of T cells and macrophages, and enhancement of type 1 regulatory T cells.

Immunosuppressive agents for myasthenia gravis

BACKGROUND

The benefits of different immunosuppressants for myasthenia gravis (MG) are unclear.

OBJECTIVES

Assessment of immunosuppressant drug efficacy in MG.

SEARCH STRATEGY

We searched the Cochrane Neuromuscular Disease Group Trials Register, MEDLINE (from January 1966 to July 2007), EMBASE (from January 1980 to July 2007), review and trial bibliographies and contacted trial authors.

SELECTION CRITERIA

Types of studies: Randomised and quasi-randomised controlled trials.

TYPES OF PARTICIPANTS

Any age, any type or severity of MG regardless of concomitant treatment. Types of interventions: Any immunosuppressive agent. Types of outcome measures: Primary: (1) Improvement or not at six months. Secondary: (1) Improvement or not at one year (2) Need for other treatment, for example corticosteroid dose, at six months (3) Number of exacerbations during the first year (4) Acetylcholine receptor antibody titre after at least six months (5) Occurrence of one or more adverse events at any time after the introduction of treatment.

DATA COLLECTION AND ANALYSIS

One author extracted and two checked the data.

MAIN RESULTS

Seven trials are included but few reported the outcomes selected for this review. A meta-analysis of ciclosporin versus placebo from two trials (59 participants) - one as monotherapy (20 participants) and the other with corticosteroids (39 participants) - showed that it resulted in improvement of participants in the ciclosporin group compared with those in the placebo group, with a relative rate of improvement of 2.44 (95% confidence interval (CI) 1.13 to 5.27). In addition the weighted mean difference in QMG score between the ciclosporin and placebo groups was -0.34 (95% CI -0.52 to -0.17). Azathioprine (plus prednisolone for first month) had no significant benefit over prednisolone alone (41 participants). The effects of azathioprine plus prednisolone versus prednisolone plus placebo were similar (34 participants). Cyclophosphamide was reported to be statistically more efficacious than placebo at 12 months in corticosteroid-dependent participants (23 participants), but no raw data were available. Trials of mycophenolate mofetil and tacrolimus did not provide relevant endpoint data for this review. All trials had low numbers of participants. Adverse event reporting was variable. Trial protocol heterogeneity prevented comparison of the different immunosuppressants.

AUTHORS' CONCLUSIONS

In generalised MG, limited evidence from small RCTs suggests that ciclosporin, as monotherapy or with corticosteroids, or cyclophosphamide with corticosteroids, significantly improve MG.Limited evidence from RCTs shows no significant benefit from azathioprine (as monotherapy or with steroids), mycophenolate mofetil (as monotherapy or with either corticosteroids or ciclosporin) or tacrolimus (with corticosteroids or plasma exchange). Bigger, better-designed, longer trials are needed.

Mycophenolate mofetil substitution for cyclosporine-dependent myasthenia gravis and nephrotoxicity

Severe autoimmune myasthenia gravis is difficult to manage and may require immunosuppression with cyclosporine. However, cyclosporine dependency is associated with the risk of nephrotoxicity. Mycophenolate mofetil is a non-nephrotoxic alternative which should be considered to rescue cyclosporine-dependent, severe myasthenia gravis sufferers with renal impairment from progression to end-stage renal failure. However, the evidence is limited and studies have not assessed the outcome of a direct substitution in these cyclosporine-dependent patients. We study three such patients who successfully converted to mycophenolate mofetil, and briefly examine the evidence behind this option. We believe that total cyclosporine withdrawal is feasible, but strongly recommend overlapping mycophenolate mofetil treatment with cyclosporine.

Guidelines for the treatment of autoimmune neuromuscular transmission disorders

Important progress has been made in our understanding of the cellular and molecular processes underlying the autoimmune neuromuscular transmission (NMT) disorders; myasthenia gravis (MG), Lambert-Eaton myasthenic syndrome (LEMS) and neuromyotonia (peripheral nerve hyperexcitability; Isaacs syndrome). To prepare consensus guidelines for the treatment of the autoimmune NMT disorders. References retrieved from MEDLINE, EMBASE and the Cochrane Library were considered and statements prepared and agreed on by disease experts and a patient representative. The proposed practical treatment guidelines are agreed upon by the Task Force: (i) Anticholinesterase drugs should be the first drug to be given in the management of MG (good practice point). (ii) Plasma exchange is recommended as a short-term treatment in MG, especially in severe cases to induce remission and in preparation for surgery (level B recommendation). (iii) Intravenous immunoglobulin (IvIg) and plasma exchange are equally effective for the treatment of MG exacerbations (level A Recommendation). (iv) For patients with non-thymomatous autoimmune MG, thymectomy (TE) is recommended as an option to increase the probability of remission or improvement (level B recommendation). (v) Once thymoma is diagnosed TE is indicated irrespective of the severity of MG (level A recommendation). (vi) Oral corticosteroids is a first choice drug when immunosuppressive drugs are necessary in MG (good practice point). (vii) In patients where long-term immunosuppression is necessary, azathioprine is recommended together with steroids to allow tapering the steroids to the lowest possible dose whilst maintaining azathioprine (level A recommendation). (viii) 3,4-diaminopyridine is recommended as symptomatic treatment and IvIg has a positive short-term effect in LEMS (good practice point). (ix) All neuromyotonia patients should be treated symptomatically with an anti-epileptic drug that reduces peripheral nerve hyperexcitability (good practice point). (x) Definitive management of paraneoplastic neuromyotonia and LEMS is treatment of the underlying tumour (good practice point). (xi) For immunosuppressive treatment of LEMS and NMT it is reasonable to adopt treatment procedures by analogy with MG (good practice point).

Basic immunosuppressive drugs outside solid organ transplantation

Immunosuppressive drugs are the backbone of solid organ transplantation. The introduction of new immunosuppressive drugs led to improved patient and organ survival rates. Nowadays, acute rejection can be reduced to a minimum. Individualization and avoidance of drug-related adverse effects became a new goal to achieve. The potency of immunosuppressive drugs makes them attractive for use in various autoimmune diseases; therefore, the experience on immunosuppressive drugs outside the field of organ transplantation is analysed in this review.

Non-ptotic ocular myasthenia gravis: a common presentation of an uncommon disease

BACKGROUND

Myasthenia gravis (MG) is an acquired autoimmune disease of the neuromuscular junction which causes rapid muscle fatigue and weakness. Two thirds of all cases of myasthenia gravis (MG) initially manifest ptosis. In the absence of the characteristic variable ptosis, MG can present a challenge to the clinician. This article will review the current diagnostic and management strategies for MG.

CASE REPORTS

Five cases will be presented that did not initially present with ptosis. Each of these cases was previously misdiagnosed as a result of presentation of atypical myasthenia gravis signs and symptoms. The first two cases had signs and symptoms of a typical accommodative/vergence anomaly. The others manifested diplopia not normally associated with MG: one had a noncomitant vertical deviation; another had a stable 6(th) nerve palsy; and the third had a basic esotropia.

CONCLUSION

Although the hallmark findings of MG are ptosis and eye muscle palsy with variability, MG may present without ptosis, affect nonstriated muscles, and/or manifest either as a nonstrabismic vergence anomaly or as comitant nonvariable strabismic deviation.

Cyclosporine in the treatment of myasthenia gravis

Cyclosporine A (CsA) treatment was evaluated in 52 patients with severe generalized myasthenia gravis (MG) whose illness was not controlled by anticholinesterase drugs, thymectomy, corticosteroids, and azathioprine. The efficacy of CsA treatment was expressed by mean disability score quotient (MDSQ), which was obtained by comparing mean disability score (MDS) at the beginning of the treatment with the MDS at the end of the follow-up period. For the entire group of patients MDSQ was 53.3%, indicating moderate improvement. Analyzing individual cases, eight patients (15%) did not improve, 17 (33%) showed moderate improvement, 20 (38%) showed remarkable improvement, and seven patients (14%) achieved complete remission. The most common side effects were rise of serum creatinine (seven), hypertension (two), gingival hyperplasia (two), hypertrichosis (six), myalgia (10), and 'flu-like' symptoms (10 patients). The results of this study suggest that CsA is efficacious and safe treatment in severe and resistant forms of MG.

Treatment and outcome of myasthenia gravis: retrospective multi-center analysis of 470 Japanese patients, 1999–2000

To clarify the current status of treatments and outcomes of patients with myasthenia gravis (MG) in Japan, a total of 470 patients (164 men and 306 women; mean age 41 years) were recruited from 19 Japanese tertiary medical centers in 1999-2000. Thymectomy was performed in 319 (68%) of the patients. Patients who received thymectomy were younger (p = 0.01) and had more severe disabilities (p < 0.01) than patients without thymectomy. Irrespective of receiving thymectomy, most of the patients were administered corticosteroids (64%), other immunosuppressive agents (10%), or cholinesterase inhibitors (86%). Of 395 patients followed up for more than 12 months after treatment (mean 8.0 years), 30% (34% of thymectomized and 21% of non-thymectomized patients) were in remission (no symptoms with/without medication), 34% had only ocular symptoms, and the remaining 35% still had weakness of bulbar or limb muscles at the end of follow-up. The prognosis of MG in Japan was generally favorable, but despite the frequent use of thymectomy and immunosuppressive treatments, approximately one-third of patients still had generalized weakness. More effective or intensive treatments are required to improve the prognosis.

Myasthenia Gravis

Myasthenia gravis is a disorder of neuromuscular transmission, manifest by variable weakness of skeletal muscle. The disorder has a range of therapies that differ with respect to efficacy, timing, and side effects. The physician treating myasthenia gravis must be well versed in understanding the evidence basis for using these agents, as well as the trade-offs between persistent disease manifestations and their costs and expected benefits. Diagnosis of myasthenia gravis depends on recognizing the pattern of weakness, which typically involves some combination of extraocular, bulbar, facial, limb, and neck muscles. Management relies on some combination of medications that influence the function of the neuromuscular junction and treatments that alter the immune response. Thymectomy is commonly used, although trends in evidence-based medicine are leading expert clinicians to look closely at its efficacy. Plasma exchange is useful for patients in crisis, who require rapid improvement. The exact role for high-dose intravenous immunoglobulin in this setting is still being studied, although the agent is gaining popularity. Knowing that the treatments are effective is not enough. It is still important to determine the treatment that has a more rapid onset, because these patients often require intensive care or respiratory assistance.

Myasthenic crisis: report of 24 cases

Myasthenic crisis (MC) is a life-threatening complication of myasthenia gravis (MG) with a high mortality rate. The aim of our study was to review the different therapeutics approaches in the treatment of MC and their impact in the final outcome. We reviewed the medical files of patients diagnosed with MG admitted between February 1993 and October 1997, who developed MC. Sex, mean age, disease's duration, functional scale, symptoms preceding the crisis, crisis therapy in each set and mortality were then analysed. There were 24 patients who developed MC, 21 females and 3 males, with 1 neonatal, 1 congenital sporadic, 17 juvenile/adult, 3 over 50 years and 2 with thymoma. Dysphagia, dysphonia and dysartria were the most common symptoms preceding the crisis. A precipitating factor was elicited in 8 cases and the most common was infection (upper airway infection, urinary tract infection and pneumonia). 16 patients needed a nasogastric tube and 9 had a tracheostomy performed. 24 patients used anticholinesterase drugs, 21 prednisone, 7 immunosuppressive agents, 5 plasmapheresis, 3 human hyperimune gamma immunoglobulin and 12 had thymectomy. A good response was obtained in 13, satisfactory in 7 and there were 4 deaths. We concluded that in spite of all the therapeutics options, there were non statistically significant differences in the outcome of patients that underwent thymectomy and those who did not.

Steroid therapy without primary dose escalation for postthymectomy crisis in 2 thymomatous myasthenia gravis patients

We report 2 cases of thymomatous myasthenia gravis associated with postoperative crisis and medicated with steroid therapy using prednisolone without primary dose escalation. Two women, a 38 years old and the other 64 years old, underwent extended thymectomy under the diagnosis of myasthenia gravis associated with invasive thymoma. Bulbar symptoms in both were severe despite preoperative anticholinesterase medication. Myasthenic crises with an antiacetylcholine receptor antibody (anti-AchR Ab) elevation were encountered in the postoperative clinical course. Daily administrations of a large amount of prednisolone without primary dose escalation and the subsequent tapering therapy effectively improved myasthenic symptoms and decreased their anti-AchR Ab titer. We also discuss difficulties in treatment in these cases.

Myasthenia gravis

BACKGROUND

In myasthenia gravis (MG), the prototypic autoimmune disease, antibodies against acetylcholine receptors impair neuromuscular transmission and produce weakness. Although recognized for several hundred years, it has only been over the last three decades that effective treatments have become available for MG.

REVIEW SUMMARY

This review summarizes the principles of normal neuromuscular transmission, the clinical features of MG, and the tests available for its diagnosis. The current treatments for MG are discussed, including possible mechanisms of action and a discussion of potential adverse effects. When available, evidence-based justification for individual treatment options is given, and areas of controversy identified.

CONCLUSIONS

Significant improvements in the diagnosis and management of MG have been made over the last several decades. The available treatments either improve neuromuscular transmission directly, or suppress or modulate the pathogenic immune response in MG. Treatment is highly individualized and must take into account the severity of disease, the presence of other diseases, and the kinetics of response for the available treatments. This requires detailed knowledge of the mechanisms of action and possible adverse effects for each treatment. However, despite an optimistic outlook with modern treatment, the management of MG continues to be plagued by lack of efficacy in some, and significant adverse effects in most MG patients.