White Matter Diseases Flashcards
what happens to myelin in MS?
degenerates
what happens to axons in MS?
nothing
what cells are lost in MS?
oligodendrocytes
what is imaging used for MS?
MRI
do acute or chronic lesions enhance on an MRI with contrast?
acute
what drives MS?
IgG antibodies…autoimmune disease
where can IgG abs be found in MS?
CSF only…none in blood
name four ways MS can present (specific symptoms0
monocular vision loss
ataxia
limb weakness or sensory loss
double vision
MS presenting with monocular vision loss is caused by demyelination where?
optic nerve (optic neuritis)
MS presenting with ataxia is caused by demyelination where?
cerebellum
MS presenting with double vision is caused by demyelination where?
brainstem
MS presenting with muscle loss and sensory weaknes is caused by demyelination where?
spinal cord
what is acute Rx for MS?
3-5 day course of steroids
over time what happens with MS? 3 things
gate difficulty
loss of bladder control
impaired cognitive function
what is a cardinal pathologic finding with MS around veins?
perivascular inflammation
where do you see changes in MS on MRI most often?
periventricular plaques…right around the ventricles the MRI will be bright white
what is ADEM?
acute disseminated encephalomyelitis
what causes acute disseminated encephalomyelitis?
post infection or vaccine
what happens in acute disseminated encephalomyelitis?
immune mediated demyelination and polyfocal neuro deficits
what are common viral infections that lead to acute disseminated encephalomyelitis?
measles
varicella and rubella
what are the two patho findings in acute disseminated encephalomyelitis?
demyelination and perivenous inflammatory infiltrates
what is PML?
progressive multifocal leukoencephalopathy
what causes progressive multifocal leukoencephalopathy?
JC virus
who gets progressive multifocal leukoencephalopathy?
immunocompromised
what happens in progressive multifocal leukoencephalopathy?
destruction of oligodendrocytes
what lobes does progressive multifocal leukoencephalopathy prefer
usually temporal and occipital
since progressive multifocal leukoencephalopathy prefers temporal and occipital, what symptom is therE?
vision changes
what white matter is destroyed in progressive multifocal leukoencephalopathy?
subcortical white matter
what can you see in oligodendrocyte in progressive multifocal leukoencephalopathy?
intranuclear inclusions of the JC virus
what is AIDS leukoencephalopathy?
diffuse pallor of cerebral white matter on myelin stain with little evidence of myelin degeneration
what is seen in histo stain for AIDS leukoencephalopathy?
multinucleated giant cells
what do they think plays role in AIDS leukoencephalopathy development?
toxic cytokines from activated microglia
what is another name for central pontine myelinolysis?
osmotic myelinolysis
what happens in central pontine myelinolysis?
rapid axonal demyelination in pons
what is cause of central pontine myelinolysis usually?
rapid osmotic changes
what is iatrogenic cause of central pontine myelinolysis?
correction of hyponatremia
what are symptoms of central pontine myelinolysis?
acute paralysis
dysphagia
diplopia
loss of consciousness
what is leukodystrophy?
inherited metabolic disease affecting white matter
what genes cause leukodystrophy?
genes that are important for myelin production or myelin lipid metabolism
where is demyelination in leukodystrophy?
CNS and PNS
what are three leukodystrophys to know?
ALD MLD and GLD
what do macros in ALD have in them?
long chain fatty acid
what do macros in MLD have in them?
sulfatide…
what do macros in GLD have in them?
galactocerebreside
describe the progression of leukodystrophies
progressive and symmetric
what is inheritance of ALD?
x linked recess
where does demyelination primarily occur in ALD?
occipital white matter and brainstem/spinal cord
what fibers are always preserved in leukodystrophy?
subcortical U fibers…just under the cortex of the brain
what do macros look like in ALD?
stuffed with lipids
what is inheritance of MLD?
AR
what is MLD an issue with?
lysosomal storage disease
what causes destruction of myelin in MLD?
cerebroside sulfate
what are symptoms of MLD?
dementia and ataxia
what is another name for GLD?
Krabbe disease
what is inheritance of GLD?
AR
what causes demyleination in GLD?
accumulation of galactocerebriside
what are symptoms of GLD?
DD, peripheral neuropathy
optic atrophy
what can happen post radiation for brain tumor?
get demyelination and radiation necrosis…this is not a new tumor but lights up white on MRI
