Myasthenia gravis - causes, symptoms, treatment, pathology

Myasthenia gravis, is a Latin expression that literally means “grave muscle weakness,”

which perfectly describes the weakness that happens when this autoimmune disease affects

the skeletal muscles.

People with myasthenia gravis might wake up feeling fine, but get progressively weaker

as the day goes on and by the end of the day they might feel very weak, sometimes even

getting weaker with repetitive movements like chopping vegetables.

Myasthenia gravis can affect the extraocular muscles, which control movement of the eye

as well as the eyelids, so individuals might have diplopia or double vision, as well as

ptosis, or drooping eyelids.

Myasthenia gravis preferentially affects young women in their 20s and 30s and older men in

their 60s and 70s, but the cause of this odd “bimodal” distribution of age-of-onset

isn’t quite clear.

To better understand myasthenia gravis, let’s review normal muscle contraction but at the

cellular level.