Myastenia gravis

Myasthenia gravis (MG) - autoimmune disorder in which antibodies form against acetylcholine nicotinic postsynaptic receptors at the neuromuscular junction of skeletal 
muscles.

2  forms of Myasthenia gravis:
 ----ocular 
 ----generalized.

 MG is one of the most treatable neurological disorders.

Initial complaint is a  weakness of the specific muscle.

----- ptosis

---- diplopia

-----ass. with thymoma

symptoms worsen with muscle use

Weakness is typically least severe in the morning and worsens as the day progresses

Weakness tends to spread from the ocular to facial to bulbar muscles and then to truncal and limb muscles

The following factors may trigger or worsen exacerbations:

• Menstruation
• Immunization
• Surgery
• Emotional stress
• Bright sunlight
• Intercurrent illness ( viral infection)
• Medication (eg, aminoglycosides, ciprofloxacin, chloroquine, procaine, lithium, phenytoin, beta-blockers, procainamide, statins)
  
  

  Management

  Therapy for MG includes the following:

  • Anticholinesterase (AchE) inhibitors
  • Immunomodulating agents
  • Intravenous immune globulin (IVIg)
  • Plasmapheresis
  • Thymectomy

  AchE inhibitors

  • Initial treatment for mild MG
  • Pyridostigmine is used for maintenance therapy^{[6, 7]}
  • Neostigmine is generally used only when pyridostigmine is unavailable
  • Corticosteroid therapy provides a short-term benefit
  • Azathioprine, usually after a dose of corticosteroids, is the mainstay of therapy for difficult cases
  • Cyclosporine A and occasionally methotrexate and cyclophosphamide are used for severe cases