Understanding the burden of refractory myasthenia gravis

Frequency and clinical features of treatment-refractory myasthenia gravis

Background

To investigate the frequency and characterize the clinical features of treatment-refractory myasthenia gravis in an Austrian cohort.

Methods

Patient charts of 126 patients with generalized myasthenia gravis and onset between 2000 and 2016 were analyzed retrospectively. Patients were classified as treatment-refractory according to strict, predefined criteria. These mandated patients being at least moderately symptomatic (i.e., MGFA class III) or needing either maintenance immunoglobulins or plasma exchange therapy for at least 1 year in spite of two adequately dosed immunosuppressive drugs. Clinical features and outcome at last follow-up were compared to treatment-responsive patients.

Results

14 out of 126 patients (11.1%) met these criteria of treatment-refractory myasthenia gravis. Treatment-refractory patients had more frequent clinical exacerbations and more often received rescue treatments or a further escalation of immunosuppressive therapies. They also remained more severely affected at last follow-up. An early onset of myasthenia gravis was associated with a higher risk for a refractory course.

Conclusion

A small subgroup of patients with generalized myasthenia gravis do not respond sufficiently to standard therapies. Refractory disease has considerable implications for both patients and health care providers and highlights an unmet need for new treatment options.

Quality of life in refractory generalized myasthenia gravis: A rapid review of the literature

Generalized myasthenia gravis (GMG) is a neuromuscular transmission disorder that creates a fluctuating weakness of the voluntary muscles. This study is aimed at understanding the effect that refractory GMG has on the quality of life of patients who suffer from it, and the effect of eculizumab on it. A systematic literature search was conducted in MEDLINE (Ovid), EMBASE and the Cochrane Database of Systematic Reviews (Ovid). Eligibility criteria were verified via the title and summary and afterward through the full text. The risk of bias of the included randomized clinical trials was evaluated and the data were synthesized in a descriptive manner. Nine studies were identified that evaluated the quality of life of patients with GMG. Regarding the effect of eculizumab, two studies were identified. The quality of life in patients with GMG is lower compared to ocular myasthenia gravis (MG) and MG in remission, especially in the domains of physical function, physical role, bodily pain, vitality, and social function. Patients treated with eculizumab had a better perception of their quality of life compared to those who received placebo. GMG affects the quality of life more than other types of MG. This outcome is of great importance for the choice of therapeutic options in patients with refractory GMG. Eculizumab generates improvements in the perception of patients' quality of life compared to placebo, making it a relevant therapeutic option in the management of refractory GMG.

Acupuncture for patients with myasthenia gravis: A systematic review protocol

BACKGROUND

The objective of this systematic review protocol is to provide the methods for evaluating the effectiveness and safety of acupuncture on the treatment of myasthenia gravis (MG).

METHODS AND ANALYSIS

We will search randomized controlled trials (RCTs) on this subject in 8 electronic databases and they are Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, PubMed, Chinese Biomedical Literature Database (CBM), China National Knowledge Infrastructure (CNKI), the Wan-Fang Database, and Chinese Scientific Journal Database (VIP database). Other relevant literatures will be manually searched as a complement. Only RCTs related to acupuncture for MG will be included, without Language restrictions and limitation of publication types. The risk of bias and trial quality will be assessed by the Cochrane collaboration tool. The study inclusion, data extraction and quality assessment will be conducted independently by 2 reviewers. All data from the studies included will be analyzed by RevMan V.5.3 statistical software.

RESULTS

This study will provide a high-quality synthesis of RCTs on the efficacy and safety of acupuncture as an adjuvant therapy in the treatment of MG.

CONCLUSION

This systemic review will provide high quality evidence to evaluate acupuncture as adjuvant therapy in patients with MG.

PROSPERO REGISTRATION NUMBER

PROSPERO CRD42019133577.

[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 a particular role in the pathophysiology of AChR antibody-positive MG, which can also manifest as a paraneoplastic disorder in the context of a thymoma. 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, a complement inhibitor, enriched the pharmacological armamentarium for AChR antibody-positive MG patients not appropriately responding to immunosuppression alone.