High Yield periphersal nerve and skeletal muscle path Flashcards
- family (canned goods)
- descending paralysis
- obligate anaerobe, gram +, spore former
- flaccid paralysis
- Floppy baby –> ingestion of spores from honey
- adult –> ingestion of preformed toxin in canned goods
Clostridium botulinum
- paralysis of posterior oral pharynx
- demyelination
- can spread to other nerves
- gram + rod
- pseudomembrane in throat
- bulls neck
- Tellurite and loefler’s media
Corynebacterium diptheriae
- Gram neg. rod, comma shaped
- can cause Guille Barre (demyelination of peripheral nerves . . ascending paralysis)
- bloody diarrhea
- lives in gut of poutry
- oxidase +
- can also cause reactive arthritis
Campylobacter jejuni
- acid fast
- symmetric neuropathy in glove and stalking pattern
- skin plaques on extensor surfaces
- lionine faces
lepromatous mycobacterium
- Northeast US
- Ixodes tick
- spirochete
Borrelia . .lyme disease
stages of lyme disease
1: bulls eye rash and flu like symptoms
2; heart block and bilateral bell’s palsy
3; migratory polyarthritis of large joints and mild encephalopathy
what type of neuropathy in DM
distal symmetric ascending sensorimotor neuropathy
Bells palsy is often associated with what
- URI
- or diabetes
what type of neuropathy is Guillain-Barre syndrome
-Acute inflammatory Demyelinating polyneuropathy . . immune mediated
in pacific islands, what has been associated with a relatively high incidence of Guillain Barre syndrome
Zika
Clinical features of Guillain Barre
- Mostly motor: ascending paralysis and areflexia, loss of pain sensation
- CSF: increase in protein and little inflammatory cells
- Treat with plasmapheresis and IVIG
- Small % don’t respond to treatment
Chronic inflammatory demyelinating poly(radiculo)neuropathy is symmetrical mixed sensorimotor polyneuropathy that persists for how long
> 2 months
onion bulb neuropathy
Chronic inflammatory Demyelinating Poly(radiculo)neuropathy
Diptheria produces an acute peripheral neuropathy associated with what
prominent bulbar and respiratory muscle dysfunction
compression of brachial plexus
Apex of lung Cx
compression of obturator nerve
Pelvic neoplasm
polyradiculopathy involving lower extremity . . compression of what
cauda equine by meningeal carcinomatosis
paraneoplastic neuropathy
- anti-Hu antibodies
- Small cell lung cancer
- CD8 mediated attack of dorsal root ganglion
POEMS syndrome
- polyneuropathy
- organomegaly
- endocrinopathy
- monoclonal gammapathy
- skin changes
describe Morton neuroma
- w>M
- compression neuropathy affecting interdigital nerve at intermetatarsal sites
- leads to foot pain
- perineural fibrosis
inherited peripheral neuropathies are often present in who
adults
what are the 3 charcot-Marie Tooth diseases . . inherited neuropathies
CMT1 (2nd decade) . AD
CMTX . X linked . genes encode connexin32
CMT2 (very early in life) . .AD . . MFN2 gene
Describe hereditary neuropathy with pressure palsy
- PMP22 gene
- compression of individual nerves at sites that are prone to entrapment
Describe the morphologic feature of nerves in Hereditary neuropathy with pressure palsy
-swollen, bulbous myelin sheaths at the end of internodes . . . Tomaculi architectures
Regardless of the cause, disorders that impair the function of neuromuscular junctions tend to present with what?
painless weakness
epidemiology of myasthenia Gravis disease
- bimodal age distribution
- female to male, 2:1
- young adults
- in older adults there is males predominance
strong association b/t myasthenia Gravis and what abnormalities
Thymic . . thymoma or thymic hyperplasia
-usually absent if in older patient tho
- fluctuating weakness that worsens with exertion
- diplopia
- ptosis
Myasthenia Gravis
Lambert-Eaton myasthenic Syndrome is an autoimmune disorder caused by antibodies that block what?
ACh release by inhibiting a presynaptic Ca channel
how do you distinguish Lambert eaton from Myathenic syndrome
Lambert eaton: repetitive stimulation increases muscle response rather than causes fatigue
about half of lambert Eaton cases associated with what
underlying malignancy most often neuroendocrine carcinoma of lung
Type II fiber atrophy with sparing of type I fibers is seen with prolonged use of what?
corticosteroids
what are the 3 inflammatory myopathies
- polymyositis
- dermatomyositis
- inclusion body myositis
polymyositis and dermatomyositis show typical features of autoimmune inflammatory diseases, including association with what genotype
HLA-DR
inflammatory myopathy that is a chronic progressive disease of older patients and associated with rimmed vacuoles
inclusion body myositis
features of Dermatomyositis
- children and adults
- latter frequently as paraneoplastic disorder
- immune damage to small blood vessels and perifascicular atrophy
- helitrope rash
- scaling erythematous eruption or dusky red patches over knuckles, elbows, and knees (Gattron papules)
autoantibodies and specific presentations of Dermatomyositis
- Anti-Mi2: Gattron papules and heliotrope rash
- Anti-Jo1: interstitial lung disease, skin rash described as “mechanic’s hands”
- Anti-P155/P140: paraneoplastic and juvenile cases
- CD4+ cells
this inflammatory myopathy is an adult onset myopathy caused by CD8 cells
polymyositis
what does polymyositis lack that dermatomyositis has
cutaneous features
Describe inclusion body myositis
- later adulthood . .older than 50. most over 65
- most severe weakness in quads
- dysphagia can occur
- cN1A
- elevated creatine kinase
- rimmed vacuoles on Gomori trichrome stain
what is the most common complication of statins
what other things cause muscle toxicity
myopathy
-unrelated to dose, cumulative dose, or statin type
- anti-malarials
- thyroid disease
- alcohol
response of inflammatory myopathies to steroids and immunosuppressive drugs
- dermatomyositis and polymyositis respond
- inclusion body myositis does NOT
congenital myopathy that has defect in ryanodine receptor-1 (RYR!)
central core disease
the 3 diseases that cause “floppy” infant
- central core disease
- Nemaline myopathy (NEM)
- Centronuclear myopathy
Duchenne and Becker muscular dystrophy are caused by what
LOF mutations in dystrophin gene on X-chromosome
morphology for muscular dystrophy
- segmental myofiber degeneration and regeneration with admixture of atrophic myofibers
- fatty replacement
- variation in size of myofibers
- absence of normal sarcolemmal staining pattern in Duchenne
- Reduced staining in Becker
Clinical features in Muscular dystrophy
- boys
- normal at birth
- walking delayed
- clumsiness and poor coordination first noted
- Pseudohypertrophy of calf muscles
- wheel chair by age 9.5 (average)
- death by 25-30
- cardiomyopathies and arrythmias
Treatment for duchenne MD
supportive care
features of myotonic dystrophy
- AD
- triplet repeat expansion
- skeletal muscle weakness
- cataracts
- endocrinopathy
- cardiomyopathy
this MD is associated with a characteristic pattern of muscle involvement that includes prominent weakness of facial muscles and muscles of the shoulder girdle
Fascioscapulohumeral dystrophy
chronic progressive external ophthalmoplegia is a common feature of what disorders
mitochondrial
- ragged red fibers
- concentric membranous rings (“phonograph record”)
mitochondrial myopathy
neuropathic disorder in which loss of motor neurons leads to muscle weakness and atrophy . . floppy infant
Spinal muscular atrophy (SMA)
morphology of SMA
rare hypertrophied myofibers admixed with numerous atrophic rounded myofibers
pathogenesis of SMA
- Autosomal recessive
- SMN1 gene
synonyms for SMA
-Werdnig-Hoffmann disease
describe subtypes of SMA and age of onset
- SMA 0: extremely weak at birth. immediate ventilation and don’t breath independently
- SMA 1: onset prior to 6 months (Werdnig Hoffman)
- SMA 2: prior to age 1. will sit but never walk
- SMA 3: after 1 will walk then lose ability
- SMA 4: before age 10
clinical manifestations of ion channel myopathies
depending on channel affected may include epilepsy, migraine, movement disorders with cerebellar dysfunction, peripheral nerve disease, muscle disease
