Final answer:
Myasthenia gravis is an autoimmune disease causing antibodies to block acetylcholine receptors at the neuromuscular junction, leading to progressive muscle weakness, especially in eye muscles, and may result in a myasthenic crisis.
Step-by-step explanation:
Pathophysiology of Myasthenia Gravis
Myasthenia gravis is an autoimmune disorder that affects the neuromuscular junction, where nerve cells communicate with muscles to initiate movement. In this disease, the immune system mistakenly produces antibodies that block or destroy nicotinic acetylcholine receptors (AChRs) at the motor endplate, which is where nerves and muscle fibers meet. This action impairs the transmission of signals from nerve to muscle, leading to muscle weakness and fatigue.Manifestations of Myasthenia Gravis
Patients with myasthenia gravis typically experience painless muscle weakness, beginning with muscles that control eye and eyelid movement, causing drooping eyelids (ptosis) and double vision (diplopia). As the condition progresses, other muscle groups become affected, leading to difficulties in chewing, swallowing, speaking, and eventually breathing. Some individuals may experience myasthenic crisis, a severe episode requiring immediate medical attention due to respiratory failure. Treatment can involve medications that inhibit the immune system or enhance neuromuscular transmission.