Myasthenia gravis is an extremely polymorphic disorder. It can be separated into individual types. In addition, neuromuscular transmission can be affected by genetic and toxic factors.

 

 Classification of neuromuscular transmission disorders based on pathogenesis

  

 

 

 

 

 

 

 

 

 

immune mediated

 

 

 

presynaptic

Lambert - Eaton myasthenic syndrome (LEMS)

aquired  neuromyotonia 

postsynaptic

myasthenia gravis

nonimmune

 

 

 

presynaptic

and postsynaptic

toxics and drugs disorders

congenitál myasthenic  syndroms (CMS)

 

 

Based on age

 

immune mediated

 

neonatal myasthenia

 

juvenile myasthenia

 

adult myasthenia

 

 

myasthenia in elderely

genenetics mediated

 

congenital myasthenic syndrom (CMS)

 

 

Based on antibody status

AChR+

85%

MuSK+

 

7%

Ab neg

 

8%

 

 

Based on antibody status

 

hyperplasia

65%

atrophy

20%

thymoma

10 - 15%

 

 

Based on disease severity and the extent of neuromuscular weakness

     The fluctuation extent and the variable predominance of the muscle group involved, makes it extremely difficult to classify the patients with MG. Most existing classifications are modifications of Osserman’s original scheme. The most widely accepted classification of myasthenia gravis is the Myasthenia Gravis Foundation of America Clinical Classification (MGFA).  More precise is Quantitative MG Score (QMG) for disease severity, that is quite complicated and is used in the objective evaluation of therapy for MG.

     There is The Myasthenia gravis composite designed by Sanders in 2008, considering factors such as disease severity according to the extent of weakness in individual muscles groups.

     There is more classification available for scientist research purposes – such as Quality of life scale,  The Postintervention Status, and others.