Myasthenia gravis


Published on

  • Be the first to comment

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide

Myasthenia gravis

  1. 1. Presented by: Jessica Faye Manansala
  2. 2.  Myasthenia gravis, an autoimmune disorder affecting the myoneural junction, is characterized by varying degrees of weakness of the voluntary muscles. Women tend to develop the disease at an early age (20-40 yrs of age) In men (60-70 yrs of age)
  3. 3.  Ocular muscle – diplopia (double vision) Ptosis (drooping of the eyelid)Major signs and symptoms Bulbar symptom- weakness of the muscle of face and throat Generalized weakness- resulting decrease vital capacity and respiratory failure Dysphonia (voice impairment)- this may result increase risk for choking and aspirationMyasthenia gravis is purely a motor disorder with noeffect on sensation or coordination.
  4. 4.  Myasthenic crisis Cholinergic crisis
  5. 5.  is an exacerbation of the diseaes process. Crisis may result from disease exacerbation or a specific precipitation event.Most common precipitator is infection; medicattion change, surgery, pregnancy and high environmental temp.Symptoms Severe generalized muscle weakness and respiratory And bulbar weakness that may result respiratory failure
  6. 6.  Symptoms of anticholinergic overmedication may mimic the symptoms of exacerbation Differentation can be achieved with the edrophonium chloride (tensilon) test.Difference between myasthenic & cholinergicMyasthenic- improves immediately following adminstration of edrophoniumCholinergic- crisis may experience no improvement or deteriorate
  7. 7. Myasthenic crisis – neostigmine methylsulfate, prostigmine is admin IM or IV until the pt. is able to swallow oral anticholinestrase meds.-plasma pheresis and IVIG- reduce antibody loadCholinergic crisis – all anticholinestrase meds should be stop- Atrophine sulfate should be given- an antidote for anticholinestrase medication.
  8. 8.  Anti cholinestrase test Edrophonium chloride (tensilon) injected through IV- 2mg at a time to a total of 10mg (30sec after injection, facial muscle weakness & ptosis should resolve for about 5min=+). Atrophine (o.4mg)should availabale for side effects. Repetitive nerve stimulation test- it records the electrical activity in target muscle after nerve stimulation. MRI- for enlarged thymus gland
  9. 9. Administration of anticholinestrase agent Pyridostigmine bromide (mestinon) & neostigmine bromide (prostigmine)Effect: provide symptomatic refief by increasing the relative concentration of available acetylcholine at the neuro muscular junction. Improve strength and less fatigueImmunosuppresive therapy CorticosteroidsEffect: to reduce production of the antibodyPrednisone taken on alternate days to lower the incidence of side effects.
  10. 10.  Plasmapheresis- blood cells & antibody containing plasma are separated, then cells and plasma substitutes are reinfused.Effect: plasma exchange used to treat exacerbations. The improvement may last only a few weeksIV immune globulin – nearly effective as plasmapheresis in controlling symptoms exacerbation. Thymectomy - it can decrease or eliminate the need for medication