Neuromuscular Diseases - Cohen Flashcards
fluctuating dementia
lewy body
fatiguing weakness
myasthenia gravis
immunology of myasthenia gravis
tumor of thymus - or very active thymus gland
path of MG
autoAbs - to ACh receptors
-blocked and destroyed
myasthenia gravis
age 20-30yo
first - around eyes
-these muscles have few ACh receptors to begin with
also - fatiguing weakness of speech and swallowing
later on - weak limbs
epidemiology of MG
younger patients - women - pregnancy or childbirth - 20-30yo
older patients - men - 50-70yo
MC if pt has other autoimmune disorder
older MG patients
men - more thymomas
course of MG
slow decline
some myasthenic crisis
-severe impairment swallowing - secretions, resp impairment, aspiration pneumonia - intubation and mechanical ventilation
diagnosis of MG
B/L ptosis - worse in one eye -extraocular palsies
-weak voice, swallowing, facial expression
strong in morning - then weaker throughout course of day
no change reflexes and no sensory changes or cerebellar involvement
circulating Abs
not in all MG patients
to ACh receptors - of skeletal muscles
nerve conduction studies
decremental response
-declining muscle response
thymoma
take it out - can cure MG
CT of MRI of chest
tensilon
short acting cholinesterase inhibitor
allows ACh to last longer at NMJ
-briefly improve MG patients
edrophonium
tensilon
AChE inhibitor
short acting - 5-10min t-1/2
tx of MG
oral cholinesterase inhibitor
-pyridostigmine (long lasting)
can also give corticosteroids
- initially get worse
- look out - its immunosuppressants
adverse of pyridostigmine
intestinal cramp, diarrhea, nausea, bradycardia, sweating
IVIG
IV IgG - tx of severe of MG
ALS
UMN and LMN disease
no involvement of extraocular muscles
also - motor CNs
atrophy of muscles
extraocular eye muscles
not affected by ALS
dysarthria
motor speech disorder
feature of ALS
can’t move tongue very well - difficulty to speak
path of ALS
cell death UMN and LMN
-from denervation
-weakness, fasciculations, atrophy, increased DTRs
UMN - motor frontal cortex, corticospinal tracts
LMN - anterior horn spinal cord to skeletal muscles
bulbar
brainstem
variation of ALS
bulbar only
UMN only
LMN only
UMN and LMN - MC form ALS
ALS prognosis
fatal all cases - w/in 5 years - especially if bulbar symptoms present
hand in ALS
lateral side - abductor pollicis brevis - more impaired
ALS diagnosis
criteria
- both UMN and LMN fxn impairment
- at least 2 levels
- BS, cervical, thoracic, lumbo-sacral
confirmed by evidence of UMN and LMN at 3 levels
increased DTR, spasticity, babknski - UMN
LMN - weak, atrophy, fasciculations
pseudobulbar affect
labile moods - crying then laughing
SOD1
mutation in ALS
diagnosis of ALS
EMG - denervation of at least 3 limbs
MRI of brain
blood test - SOD1, TFT, lyme, B12, ANA, PTH, west nile, heavy metals, HIV, HTLV-1
tx of ALS
glutamate antagonist - riluzole
prolongs life - time to resp failure
damages liver
lou gehrigs disease
ALS