Diseases of the Muscular System

Myasthenia gravis

Myasthenia gravis (MG) is a condition where the body's own defense, the immune system, attacks the body. In MG, the intersection between nerve and muscle is the target, causing a blockade of signals that would otherwise command the muscle to go into action. The result is debilitating fatigue to the point where the affected individual is completely incapacitated.

Cause: MG is what is called an autoimmune disorder. In some cases, the origin is genetic.

Symptoms: The onset of myasthenia gravis can be sudden and symptoms may vary in severity. Muscle weakness is the leading symptom, especially after activity, as well as fatigue, drooping eyelids, trouble swallowing, and shortness of breath.

Treatment: Drugs called cholinesterase inhibitors are capable of elevating the messenger chemicals between the nerve and muscle, which can partially compensate for the interrupted communication between these two systems. In adults, surgical removal of the immune cell factory, the so-called thymus gland, may provide benefits, although this will result in an overall compromised immune system.  

Muscular Dystrophy

There are more than 100 diseases that have the symptoms of muscular dystrophy or involve the degradation of muscles. For some, the affliction is so severe that patients’ lives are cut short, but others can live into adulthood.

Cause: Most muscular dystrophies are inherited genetically and result from mutations in proteins that make up the muscles. These defects in muscle proteins lead to the death of muscle cells. 

Symptoms: Weakening muscles, difficulty walking or maintaining balance, drooping eyelids, curved spine, and problems breathing are all symptoms of muscular dystrophy.

Treatment: There is no cure for muscular dystrophy. Usually the symptoms are treated individually. Inactivity can worsen the disease. Physical therapy and devices like wheelchairs and walkers can be helpful. People with severe muscular dystrophy may need assisted living.