FREE ESSAY ON MYASTHENIA GRAVIS

MYASTHENIA GRAVIS

Myasthenia Gravis (MG) is a chronic autoimmune disorder of neuromuscular transmission
resulting in muscle weakness. The term "myasthenia" is latin for muscle weakness, and
"gravis" for grave or serious. Myasthenia gravis is characterized by decremental neuronal
response with repetitive nerve stimulation, and evidences itself in a few characteristic,
physical ways. The typical symptoms for a myasthenic patient to have a flattened smile
and droopy eyes, with slow papillary light responses. The patient may have fixed column
deformity, or irregular posture after standing for a short time period. Nasal speech,
difficulty chewing and swallowing, dulled facial expression, including difficulty smiling
and an ineffective cough due to weak expiratory muscles, difficulty talking, weakness or
paralysis that worsens with exertion later in the day, difficulty climbing stairs,
difficulty lifting objects, are all also frequently associated with MG.
MG involves fluctuating levels of weakness of commonly used muscles. Weakness occurs when
the nerve impulses does not adequately reach the muscle cells which is caused by blockage
of the action of neurotransmitters. Acetylcholine Receptors on the muscles are actually
destroyed by the immune system, thus it is an immune response of the body against itself.
High levels of antibodies block the action of neurotransmitters. The cause of autoimmune
disorders such as MG is unknown. In some cases it may be associated with tumors of the
thymus. MG affects an estimated 3 out of 10,000 people.