Medical Surgical Myasthenia Gravis MG #3

Question

Which symptom below would a nurse most likely see with a client diagnosed with myasthenia gravis (MG)?

Answers

  1. Nuchal rigidity
    • Rationale:

      This answer is not correct because nuchal rigidity occurs with encephalitis, not MG. MG causes muscle weakness and fatigue.

  2. Monotonous speech
    • Rationale:

      This answer is not correct since monotonous speech is associated with Parkinson’s disease. A client with MG may have a hoarse, weak voice due to the fatigue of the tongue.

  3. Flaccid facial muscles
    • Rationale:

      This answer is not correct because flaccid facial muscles are a symptom of Bell’s Palsy due to damage to cranial nerve VII. MG causes weakness in facial muscles, but not paralysis.

  4. Drooping of the eyelid
    • Rationale:

      This answer is correct because one of the hallmark signs of MG is ptosis (drooping of the eyelid) and double vision. Muscle weakness of the levator palpebrae superioris causes lid fatigue which results in ptosis. This may worsen as the day progresses due to muscle fatigue. Weakness of the extraocular muscles causes the eyes to misalign and results in double vision.

Overview

Myasthenia gravis (MG) is a chronic autoimmune neuromuscular disease that causes weakness in skeletal muscles. Vision changes, difficulty swallowing, breathing, ptosis (drooping of the eyelid), and peripheral weakness are symptoms, and may worsen as the day progresses.

Explanation

Learning Outcomes

Myasthenia gravis is a chronic autoimmune neuromuscular disease that causes weakness in skeletal muscles including those that control breathing and eye movement. Symptoms of MG may worsen as the day progresses. The transition between where nerve cells bridge with muscles is impaired in clients with MG. Antibodies block receptors for acetylcholine at the neuromuscular junction which prevents muscular contraction. This ultimately results in voluntary muscle weakness causing fatigue, diplopia, facial paralysis, dysphagia, or ptosis. Treatment includes cholinesterase inhibitors which increase communication between the nerve cells and muscles and immunosuppressant drugs such as corticosteroids to suppress the body’s immune response. The last option is intravenous immunoglobulin therapy where the client receives normal antibodies to help strengthen the immune system.

Test Taking Tip

Know the symptoms of neurological disorders and understand their differences.

Video Rationale