Posted on Jan 18, 2008 | Comments 0
About one twenty thousand people in America are affected by myasthenia gravis (MG).
This disease happens when the antibodies produced by the immune system damage acetylcholine receptors, which play a key role in transmitting the electrical impulses that cause muscles to move.
The immune response at the heart of this abnormal process is called as complement cascade, which is a complex chain of chemical reaction where proteins bind together and attacks a cell by punching a hole in that cell. In this way, acetylcholine receptors will get damaged causing severely impaired muscle movement.
It is necessary to make a note that myasthenia gravis cannot be cured, but many therapies are there to reduce the symptoms.
Does Myasthenia Gravis Effects Ocular Muscles?
Myasthenia gravis affecting eye muscles is ocular myasthenia gravis. Ocular MG is a disease seen at the neuromuscular junction resulting in muscle weakness/fatigability of the eyelids and eye movement.
Ptosis (drooping of the upper eyelid) and diplopia are characteristic features of myasthenia gravis or other muscular dystrophies.
The patients with myasthenia gravis mostly complain about oral (swallowing disorders), throat (dysarthria), and voice (dysphonia) problems.
Swallowing problem (dysphagia) accompanied by ocular fatigue is an early sign of myasthenia gravis. Approximately 33% of myasthenia gravis patients are affected by dysphagia.
This disease also involves other parts of the muscle groups.
New Treatment To Prevent Or Restore Muscle Weakness Caused By Myasthenia Gravis:
According to the new research of St. Louis University School of Medicine, muscle weakness caused by myasthenia gravis can be prevented or can be reversed by interfering with the immune response, which causes the disease.
By using an animal model, St. Louis University School of Medicine scientists found that they can stop muscle weakness or can bring back muscle strength by stopping the complement cascade at C5 step.
They did this by dispensing an anti-C5 agent or eculizumab that targets one of the proteins involved in the cascade and stops it before damaging the acetylcholine receptors.
According to Dr. Henry J. Kaminski, chairman of neurology and psychiatry at the school, the research findings on animals are promising enough that human clinical trials involving anti-C5 agent (eculizumab) are likely to start next.
Dr. Kaminski said, “We believe this therapeutic approach has strong potential for improving the lives of the patients with myasthenia gravis.”
He also added “If it proves successful there, it could also help us to find new therapies for other autoimmune disorders, such as rheumatoid arthritis, lupus, and others.”
Common treatments for myasthenia gravis include using medications, thymectomy (removal of thymus), and plasmapheresis (plasma exchange).
Anticholinesterase agents, corticosteroids, immunosuppressive agents, and intravenous immunoglobulins are some of the medication therapy used to treat the myasthenia gravis.
MG can also sometimes be treated with surgery by removing thymus, which also plays a role in the immune system. Plasmapheresis may also be useful in the treatment of MG.
Since there is no cure for myasthenia gravis, the treatment goal is to reduce the symptoms caused by this disease. The decision of treatment is based on severity, age, sex, degree of impairment, and response to any specific form of therapy in the past.
Posted in: Immune Disorders