Flashcards in 022614 1 Neuromuscular Diseases Pathology SDL Deck (22):
What are the three categories of peripheral nerve disorders?
What type of disease is guillain-barre syndrome?
What is guillain-barre syndrome?
rapid, ascending, symmetrical demyelination of motor axons only beginning distally, eventually leading to respiratory weakness.
What is chronic inflammatory demyelinating polyneuropathy (CIDP)?
Chronic GBS, but less severe, involves sensory axons too, and follows relapsing course.
What three findings are characteristic of diabetic polyneuropathy?
accumulation of glycosylation end products
increased protein C levels
What is a clinical finding in myasthenia gravis other than anti-Ach autoantibodies and muscle specific kinase antibody (MUSK)?
ptosis and diplopia due to weakened extraocular muscles
What happens during lambert eaton syndrome (LEMS)?
autoantibodies inhibit calcium channels which reduces release of Ach
Do clostridium tetani and clostridium botulinum release neurotoxins that interfere with NMJ’s?
Emery dreifuss muscular dystrophy (EMD) is characterized by what?
mutations in emerin or lamin A/C
Hyperkalemic periodic paralysis is characterized by what?
mutation in sodium channel protein SCN4A
Malignant hyperthermia is characterized by what?
mutations in ryanodine receptor
What are the three inflammatory myopathies?
inclusion body myositis
Histologic findings in polymyositis?
increased expression of MHC-1 on myofibers leading to autoimmune attack by cytotoxic T cells,
Histologic findings in dermatomyositis?
pain and rash
Inclusion body myositis is characterized by what?
Inclusion body myositis is resistant to steroids. T or F?
What is the primary finding in mitochondrial myopathy?
ragged red fibers
Myofiber degeneration/regeneration, internalization of nuclei, scar formation, and inflammation
are general changes that occur during ______?
What are the three congenital myopathies?
central core myopathy
rod body myopathy
What is present during early denervation?
small angular fibers due to loss of motor unit
What is present during chronic denervation?
large motor units due to fiber type grouping and axonal sprouting