What is myasthenia gravis?
Myasthenia gravis is a medical condition characterized by autoantibodies against acetylcholine receptors at the neuromuscular junction, resulting in muscle weakness. Patients often have involvement of their ocular (eye) and bulbar muscles. The bulbar muscles are located in the head and are important for chewing and swallowing. Symptoms often include double vision, eyelid drooping, slurred speech, and dysphagia (trouble swallowing) due to muscle fatigue – this is particularly worse at the end of the day.
Patients may have acute flares of disease referred to as “myasthenic crisis.” During these episodes, patients have muscle weakness involving the diaphragm, which is a critical muscle for breathing. …show more content…
Patients with myasthenia gravis frequently have abnormalities of the thymus gland such as thymoma (thymus tumor). This may be a possible source of antibody formation as symptoms of myasthenia gravis frequently resolve after thymectomy (thymus removal surgery).
How common is myasthenia gravis?
Myasthenia gravis is a relatively uncommon disorder, but is the most common form of neuromuscular disease. The condition typically requires referral to a neurology specialist.
Myasthenia gravis has a bimodal age distribution with an early peak around age 20-30 and a late peak at age 60-80. Its incidence is approximately 7-23 new cases per 1 million people per year and its prevalence is approximately 70-320 cases per 1 million people. Disease prevalence is on the rise.
What are the symptoms and signs of myasthenia gravis?
Symptoms of myasthenia gravis often include fluctuating muscle weakness with muscle fatigue. Muscle weakness is worse with activity and often at the end of the …show more content…
Patients with myasthenic crisis resulting in respiratory failure typically require plasmapheresis and IVIG therapy.
Summary:
• Myasthenia gravis is an autoimmune disease characterize by antibodies against acetylcholine receptors at the neuromuscular junction.
• Patients frequently have abnormalities of the thymus gland such as thymoma. This may be a possible source of antibody formation as symptoms frequently resolve after thymectomy (thymus removal surgery).
• Symptoms often include fluctuating muscle weakness with muscle fatigue. Muscle weakness is often worse with activity and at the end of the day.
• Patients typically have ocular symptoms such as double vision (diplopia) and ptosis (droopy eyelid). They also frequently develop bulbar symptoms such as trouble swallowing (dysphagia) and slurred speech (dysarthria).
• Involvement of the respiratory symptom is one of the condition’s most dreaded complications as it can lead to respiratory failure and death – “myasthenia crisis.”
• The bedside ice pack test supports the diagnosis. Sometimes your doctor will perform an edrophonium (Tensilon)