There are some pathologies in the human body that exist without the person knowing about them. They can exist from childhood or occur late in life, however, the person can only discover about that disease once they start showing symptoms with time. These persistent sets of symptoms are what give clues to something wrong happening inside the body. Myasthenia Gravis is one such pathology that is discovered over time, with a pathology that cannot be corrected. There are many disorders and some are autoimmune in nature. Therefore, these disorders exist due to the body’s own cells attacking the healthy cells of the body. This leads to the destruction of the normal tissues and eventually the loss of function of that particular part of the body.
Myasthenia Gravis is an autoimmune disorder that has defects in the functioning of the neuromuscular junction. All the nerve impulses travel through particular nerves to send signals to the muscles to contract. Problems in the binding of proper structures on the nerve terminals result in the inability of the muscles to contract properly. This leads to muscle weakness and the inability to carry out day-to-day activities. There are many individuals who have been diagnosed with this disorder but not much can be done to completely reverse it. Therefore, the ones who suffer from Myasthenia Gravis, suffer from it all their lives. There are drugs that prevent the disease from worsening, with surgery being the last resort to somewhat manage the symptoms.
It is not a very common disorder and affects 20 out of 100,000 individuals in the US per year. It has been seen that females get affected by this more than males with the ratio being 3:1. Moreover, it is also seen that people over the age of 40 are the ones who start showing symptoms of this disease.
Pathophysiology
The pathology through which Myasthenia Gravis affects the body is by attacking the muscular and the nervous system of the body. Nerves communicate along with the muscles by discharging chemicals that are called neurotransmitters. These neurotransmitters then fit accurately into their receptors. These receptors identify the particular neurotransmitter and send signals to the muscle to contract. The muscle cells at the nerve-muscle junction are called the motor endplate.
However, in myasthenia gravis, there are antibodies produced inside the body of the immune system that goes on to attach to the receptors that are present on the muscles that are supposed to attach to the actual neurotransmitter; Acetylcholine. Therefore with less amount of receptors available for the molecule of Acetylcholine to attach, the muscle cannot contract properly and result in weakness.
These antibodies also block the function of another receptor, called the muscle-specific tyrosine kinase receptor. With all these paths blocked, the muscle is unable to contract properly. With the increase in the production of these defective antibodies, the severity of the disease increases, as it targets other areas of the body, starting from the eyes and then going all the way to the limbs and the respiratory muscles.