What are the two types of myasthenia gravis?

What are the two types of myasthenia gravis?

• A. Congenital—deficient in acetylcholine receptors and antibodies against acetylcholine receptors
• B. Demyelinating neuropathy
• C. Autoimmune destruction of GABA receptors
• D. Metabolic myopathy with mitochondrial dysfunction

Answer: (A)

Myasthenia gravis can be categorized into two forms: congenital and autoimmune (acquired). The congenital form arises from developmental or genetic defects that reduce the number or function of acetylcholine receptors at the neuromuscular junction, leading to impaired muscle signaling. The autoimmune form occurs when the immune system produces antibodies that attack acetylcholine receptors, decreasing receptor availability and blocking transmission. Together, these describe the two main pathways to MG: a receptor deficiency seen from birth and an antibody-mediated disruption that develops later. The other options describe conditions that are not myasthenia gravis: demyelinating neuropathy affects the nerve’s insulation rather than the NMJ receptors; autoimmune destruction of GABA receptors targets brain/spinal cord inhibitory signaling rather than the NMJ; and metabolic myopathy with mitochondrial dysfunction involves energy production in muscle rather than postsynaptic receptor function.

Myasthenia gravis can be categorized into two forms: congenital and autoimmune (acquired). The congenital form arises from developmental or genetic defects that reduce the number or function of acetylcholine receptors at the neuromuscular junction, leading to impaired muscle signaling. The autoimmune form occurs when the immune system produces antibodies that attack acetylcholine receptors, decreasing receptor availability and blocking transmission. Together, these describe the two main pathways to MG: a receptor deficiency seen from birth and an antibody-mediated disruption that develops later.

The other options describe conditions that are not myasthenia gravis: demyelinating neuropathy affects the nerve’s insulation rather than the NMJ receptors; autoimmune destruction of GABA receptors targets brain/spinal cord inhibitory signaling rather than the NMJ; and metabolic myopathy with mitochondrial dysfunction involves energy production in muscle rather than postsynaptic receptor function.