Myasthenia Gravis

Myasthenia gravis, a well-defined clinical entity for more than a century, was considered to be a disorder of grave prognosis till the 1930s. It is an immune-mediated neuromuscular junction transmission disorder with antibodies directed primarily toward nicotinic acetylcholine receptor proteins located in the junction. The autoimmune attack leads to skeletal muscle weakness, characterized by fatigable weakness, typically improved after rest or upon arising in the morning and worsened as the day passes. The disorder is also characterized by diplopia, ptosis, dysarthria, and dysphagia. Myasthenia gravis can develop at any age, though it is more common in younger and middle-aged with a female preponderance. Since the disorder is limited to the neuromuscular junction, mentation, and sensory and autonomic systems, functions are normal. The unique thymus gland involvement in the disease process had opened a better understanding of the autoimmune mechanism and led to the identification of distinct myasthenia gravis subgroups. The medical treatment consists of combinations of symptomatic drug therapy, immunosuppressive drug therapy, thymectomy, and supportive therapy. This chapter discusses the epidemiology, clinical manifestations, classification, pathological and investigation findings, diagnosis, medical, surgical management, and physiotherapy management.