Myasthenia Gravis (MG) is an autoimmune disorder characterized by muscle weakness that ranges from mild weakness of specific muscle groups to severe weakness of multiple muscle groups. MG affects approximately 20 per 100,0001 patients and arises from antibody-mediated synaptic dysfunction of the transmission of nerve impulses to muscle fibers at the neuromuscular junction. This disruption involves either acetylcholine receptors (AChR) or muscle-specific kinase receptors (MuSK) that ultimately inhibit muscle contraction. Onset of symptoms is generally gradual, but can sometimes be acute following viral infection or pregnancy.
Symptoms of Myasthenia Gravis
What are the symptoms of MG?1,2
AChR Positive Patients
MuSK Positive Patients
1Haven TR, Astill ME, Pasi BM. An Algorithm for Acetylcholine Receptor Antibody Testing in Patients with Suspected Myasthenia Gravis. Clinical Chemistry. 2010; 56(6): 1028-1029.