Myasthenia Gravis

Myasthenia gravis is a chronic neuromuscular disease that leads to fluctuating muscle weakness and fatigue. The disease that is characterized by variable degrees of weakness of the skeletal muscles. The name myasthenia gravis is derived from a Latin word, meaning “grave muscle weakness.”

Myasthenia Gravis

The muscle weakness happens mainly due to the circulation of antibodies which block nicotinic acetylcholine receptors at the postsynaptic neuromuscular junction. By blocking the ability of the neurotransmitter acetylcholine to bind to these receptors in the muscle, these antibodies deter motor neurons from signaling the muscle to contract.

Alternatively, in a much rarer form, muscle weakness is the result of a genetic defect in some portion of the neuromuscular junction that is inherited at birth as compared to the development through passive transmission from the mother’s immune system at birth or through autoimmunity later in life.

Myasthenia Gravis Symptoms

The major symptom of myasthenia gravis is in the form of weakness in the voluntary skeletal muscles, that are the muscles which control the area. The muscles fail to contract as they are unable to respond to nerve impulses. Without proper transmission of the impulse, the communication is blocked between nerves and muscles.

Myasthenia Gravis Symptoms

Myasthenia Gravis Symptoms

Symptoms of myasthenia gravis include:

  • Difficulty in talking
  • Problems in lifting objects and  walking up stairs
  • Difficulty in breathing due to muscular weakness
  • Difficulty in swallowing or chewing
  • Hoarse voice
  • Drooping of eyelids
  • Double vision

Although myasthenia gravis could affect any of the muscles that you control voluntarily, certain muscle groups are more commonly affected than others some of them are:

  1. Eye Muscles
  • Drooping of one or both eyelids.
  • Double vision.
  1. Face and Throat Muscles
  • Altered speaking
  • Difficulty swallowing
  • Problems in chewing
  • Limited facial expressions

Myasthenia Gravis Causes

Myasthenia gravis is resulted by a defect in the transmission of nerve impulses to muscles. It occurs when normal communication between the nerve and muscle is interrupted at the neuromuscular junction—the place where nerve cells connect with the muscles they control.

This neuromuscular disease is caused by transmission defects in nerve impulses to muscles. The neuromuscular junction is apparently affected: acetylcholine, which produces muscle contraction under normal conditions no longer produces the contractions necessary to muscle movement.

Myasthenia Gravis Treatment

Myasthenia gravis is believed to be caused by variations in certain genes. The disorder occurs when the immune system malfunctions and attacks the body’s tissues. There is no cure for myasthenia gravis. The goal of treatment is to manage symptoms and control the activity of your immune system through the below-mentioned ways:

  • Medication
  • Thymus Gland Removal
  • Plasma Exchange
  • Intravenous Immune Globulin
  • Lifestyle Changes
  • Rest to help minimize muscle weakness.
  • Avoid stress and heat exposure.

For more detailed information about Myasthenia Gravis, visit Byju’s.


Practise This Question

Secondary succession takes place in :