Clinical presentations of myasthenia gravis

This chapter describes signs and symptoms characteristic for postsynaptic neuromuscular junction diseases, how to validate them, and when to attribute them to myasthenia or another neurological disease. Non-motor symptoms in myasthenia will be discussed separately with a special reference to “fatigue.” We propose a bedside examination policy. The clinical course of myasthenia and how it may be influenced by external factors are described; several clinical subgroups are identified: congenital vs. acquired, anti-AChR vs. anti-MuSK vs. seronegative, pure ocular vs. generalized, thymoma vs. no thymoma, and early onset vs. late onset in a-AChR+ patient. 

The epidemiology of myasthenia is described for the whole population of patients and according to age, gender, and thymic histology. Familial autoimmune myasthenia and congenital myasthenia are described separately. The increase in incidence and prevalence and the shift to “old age” are discussed and explained by increase of life expectancy, improvement of general knowledge on myasthenia, and new diagnostic tests.