Myasthenia gravis and related disorders: Pathology and molecular pathogenesis

Highlights

• Diseases of neuromuscular junction result from immune, toxic, genetic pathologies

• Most common: autoimmune anti-acetylcholine receptor myasthenia gravis

• Lambert-Eaton myasthenic and Guillain-Barre syndromes target presynaptic sites

• Botulinum toxin and organophosphates block synaptic transmission

• Mutations in various synaptic proteins cause congenital myasthenic syndromes

Abstract

Disorders affecting the presynaptic, synaptic, and postsynaptic portions of the neuromuscular junction arise from various mechanisms in children and adults, including acquired autoimmune or toxic processes as well as genetic mutations. Disorders include autoimmune myasthenia gravis associated with acetylcholine receptor, muscle specific kinase or Lrp4 antibodies, Lambert–Eaton myasthenic syndrome, nerve terminal hyperexcitability syndromes, Guillain Barré syndrome, botulism, organophosphate poisoning and a number of congenital myasthenic syndromes. This review focuses on the various molecular and pathophysiological mechanisms of these disorders, characterization of which has been crucial to the development of treatment strategies specific for each pathogenic mechanism. In the future, further understanding of the underlying processes may lead to more effective and targeted therapies of these disorders. This article is part of a Special Issue entitled: Neuromuscular Diseases: Pathology and Molecular Pathogenesis.