Objectivity, practicality, and significance of practice guidelines for the practicing neurologists: What we learnt from consensus criteria in CIDP, Myasthenia Gravis and Inflammatory Myopathies

Towards personalized management of myasthenia gravis phenotypes: From the role of multi-omics to the emerging biomarkers and therapeutic targets

Predicting the onset, progression, and outcome of rare and chronic neurological diseases, i.e. neuromuscular diseases, is an important goal for both clinicians and researchers and should guide clinical decision-making and personalized treatment plans. A prime example is myasthenia gravis (MG), an antibody-mediated disease that affects multiple components of the postsynaptic membrane, impairing neuromuscular transmission and producing fatigable muscle weakness. MG is characterized by several clinical phenotypes, defined by a broad spectrum of factors, which have contributed to the current lack of consensus on the optimal management and treatments of this disease and its related phenotypes (subtypes). This represents a crucial challenge in MG and encourages a revolutionary change in diagnostic, prognostic and therapeutic guidelines. Emerging factors, such as demographic, clinical and pathophysiological factors, must also be considered. Consequently, the different MG phenotypes are characterized by precise biological signatures, which could represent appropriate biomarkers and targets. Here we describe and discuss these new concepts, highlighting that, thanks to multi-omics technologies, the identification of emerging diagnostic/prognostic biomarkers, such as miRNAs, and the subsequent development of new diagnostic/therapeutic algorithms could be facilitated. The latter, in turn, could facilitate the management of different MG phenotypes also in a personalized manner. Limitations and advantages are also reported.

Autoimmune inflammatory myopathy biomarkers

The autoimmune inflammatory myopathy disease spectrum, commonly known as myositis, is a group of systemic diseases that mainly affect the muscles, skin and lungs. Biomarker assessment helps in understanding disease mechanisms, allowing for the implementation of precise strategies in the classification, diagnosis, and management of these diseases. This review examines the pathogenic mechanisms and highlights current data on blood and tissue biomarkers of autoimmune inflammatory myopathies.

Guideline for the management of myasthenic syndromes

Myasthenia gravis (MG), Lambert-Eaton myasthenic syndrome (LEMS), and congenital myasthenic syndromes (CMS) represent an etiologically heterogeneous group of (very) rare chronic diseases. MG and LEMS have an autoimmune-mediated etiology, while CMS are genetic disorders. A (strain dependent) muscle weakness due to neuromuscular transmission disorder is a common feature. Generalized MG requires increasingly differentiated therapeutic strategies that consider the enormous therapeutic developments of recent years. To include the newest therapy recommendations, a comprehensive update of the available German-language guideline 'Diagnostics and therapy of myasthenic syndromes' has been published by the German Neurological society with the aid of an interdisciplinary expert panel. This paper is an adapted translation of the updated and partly newly developed treatment guideline. It defines the rapid achievement of complete disease control in myasthenic patients as a central treatment goal. The use of standard therapies, as well as modern immunotherapeutics, is subject to a staged regimen that takes into account autoantibody status and disease activity. With the advent of modern, fast-acting immunomodulators, disease activity assessment has become pivotal and requires evaluation of the clinical course, including severity and required therapies. Applying MG-specific scores and classifications such as Myasthenia Gravis Activities of Daily Living, Quantitative Myasthenia Gravis, and Myasthenia Gravis Foundation of America allows differentiation between mild/moderate and (highly) active (including refractory) disease. Therapy decisions must consider age, thymic pathology, antibody status, and disease activity. Glucocorticosteroids and the classical immunosuppressants (primarily azathioprine) are the basic immunotherapeutics to treat mild/moderate to (highly) active generalized MG/young MG and ocular MG. Thymectomy is indicated as a treatment for thymoma-associated MG and generalized MG with acetylcholine receptor antibody (AChR-Ab)-positive status. In (highly) active generalized MG, complement inhibitors (currently eculizumab and ravulizumab) or neonatal Fc receptor modulators (currently efgartigimod) are recommended for AChR-Ab-positive status and rituximab for muscle-specific receptor tyrosine kinase (MuSK)-Ab-positive status. Specific treatment for myasthenic crises requires plasmapheresis, immunoadsorption, or IVIG. Specific aspects of ocular, juvenile, and congenital myasthenia are highlighted. The guideline will be further developed based on new study results for other immunomodulators and biomarkers that aid the accurate measurement of disease activity.