Myasthenia Gravis: Symptoms, Causes, diagnosis and treatment.

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Myasthenia Gravis

• CAUSES SYMPTOMS DIAGNOSIS TREATMENT

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Introduction to Myasthenia Gravis

• Myasthenia Gravis is a neuromuscular disorder
  primarily characterized by muscle weakness and
  muscle fatigue. Although the disorder usually
  becomes apparent during adulthood, symptom onset
  may occur at any age.
• The condition may be restricted to certain
  muscle groups, particularly those of the eyes
  (ocular myasthenia gravis), or may become more
  generalized (generalized myasthenia gravis),
  involving multiple muscle groups.
• Most individuals with myasthenia gravis develop
  weakness and drooping of the eyelids (ptosis)
  weakness of eye muscles, resulting in double
  vision (diplopia) and excessive muscle fatigue
  following activity.

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Causes of Myasthenia Gravis

• Myasthenia Gravis is a neuromuscular
  disorder that is usually caused by an autoimmune
  problem.
• Autoimmune disorders occur when the immune system
  mistakenly attacks healthy tissue.
• In this condition, antibodies (proteins which
  normally attack foreign, harmful substances in
  the body) attack the neurotransmitter substance
  called acetylcholine, which is a crucial
  substance for nerve cell and muscle
  communication.
• This results in the muscle weakness that
  characterizes the condition. The exact cause of
  this autoimmune reaction is unclear to the
  doctors.

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Symptoms of Myasthenia Gravis

• Symptoms may include
• Trouble talking
• Problems walking up stairs or lifting objects
• Facial paralysis
• Difficulty breathing because of muscle weakness
• Difficulty swallowing or chewing
• Fatigue
• Hoarse voice
• Drooping of eyelid
• Double vision

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Diagnosis of Myasthenia Gravis

• Your doctor will perform a complete physical
  exam, as well as take a detailed history of
  symptoms. He or she will also do a neurological
  exam. This may consist of Checking your
  reflexes
• Looking for muscle weakness
• Checking for muscle tone
• Making certain your eyes move properly
• Testing sensation in different areas of your body
  
• Seeing if you can perform certain movements, like
  touching your finger to your nose

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Diagnosis Continue

• Other tests that can help your doctor diagnose
  the condition include
• Repetitive nerve stimulation test
• Blood testing for antibodies associated with
  Myasthenia Gravis
• Edrophonium (Tensilon) test a drug called
  Tensilon (or a placebo) is injected, and the
  patient is asked to perform muscle movements
  under doctor observation
• Imaging of the chest, using CT scans or MRI, to
  rule out a tumour

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Treatments of Myasthenia Gravis

• Common treatments for myasthenia gravis include
• Medications such as Mestinon (pyridostigmine
  bromide) and Prostigmin (neostigmine bromide)
• Corticosteroid medications such as prednisone
• Medications that suppress the immune system, such
  as Imuran (azathioprine) and cyclosporine
• Removal of the thymus gland (thymectomy), the
  main gland in the immune system
• Plasma exchange (plasmapheresis), in which the
  person's blood plasma containing the abnormal
  antibodies is removed and fresh plasma is put
  back

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Preventions of Myasthenia Gravis

• Myasthenia gravis cannot be prevented, but
  avoiding the following triggers may help patients
  prevent exacerbation
• Emotional stress
• Exposure to extreme temperatures
• Fever
• Illness (e.g., respiratory infection, pneumonia,
  tooth abscess)
• Low levels of potassium in the blood
  (hypokalemia caused by diuretics, frequent
  vomiting)
• Medications (e.g., muscle relaxants,
  anticonvulsants, certain antibiotics)
• Overexertion