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Flashcards in Demyelinating Diseases of the CNS Deck (44):

When is the peak incidence of MS?

between 20-30 years of age


What is the definition of MS?

multiple white matter lesions separated in space and time


What is a common initial presenting symptom of MS involving the eye?

optic neuritis - painful loss of visual acuity in one eye

pain is usually most prominent with movement of the eye. the visual acuity loss can be blurry vision, maybe loss of color discrimination and a severe episode can lead to blindness


What are some findings that would suggest a previous optic neuritis?

red desaturation
optic disc pallor or atrophy
a relative afferent pupillary defect


Describe how transverse myelitis (common in MS) might present.

unilateral or bilateral weakness and/or sensory loss below the lesion

bowel and bladder function may be lost

reflexes may be exaggerated below the lesion and a babinski sign may be present


Describe internuclear opthalmoplegia, which is characteristic of MS.

dysfunction of the medial longitudinal fasciculus that leads to an inability to adduct one eye when looking toward the opposite side with an associated nystagmus of the abducting eye

adduction in convergence is preserved


What is Lhermitte's sign?

a tingling, electric sensation down the spine when the patient flexes the neck


What is Uhthoff's phenomenon?

worsening of MS symptoms when exposed to hot temperatures


What are the four general clinical courses of MS?

benign MS
secondary progressive
primary progressive


Describe the course of benign MS

the nice one - minimal to no accumulated disability and few attacks, returning to normal between attacks


Describe the course of relapsing-remitting MS.

a series of attacks between which the patient does not return to baseline. however, there is no new disability between attacks.

this is the most common type


Describe the course of secondary progressive MS.

It starts out as relapsing-remitting, but then transforms to have progressive disability with or without acute attacks


Describe primary progressive MS.

this is the bad one

you just have a steady increase in disability without acute attacks


What are some good prognostic features in MS?

young age at onset
female sex
rapid remission of initial symptoms
mild relapses leaving little or no residual deficits
presentation with sensory symptoms or optic neuritis as opposed to motor symptoms


What are the two most useful evaluation studies for MS?

CSF analysis


What will you see on MRI in MS?

new MS lesions as discrete T2-hyperintense areas in the white matter of the brain and spinal cord

ovoid lesions are classic

FLAIR sequences show these lesions particularly well

acute lesions my not be evident on T1, but will enhance with gadolinium


MS lesions have a predilection for what areas?

periventricular white matter
juxtacortical regions
corpus callosum
cerebellar peduncles


In MS, sagittal images may demosntrate foci of demyelination spreading perpendicularly from the corpus callosum, called what?

Dawson's fingers


What is the characteristic CSF finding in MS?

oligoconal bands

intrathecal production of IgG antibodies by plasma cell clones

(during an acute exacerbation, CSF analysis may also show a moderate pleocytosis and elevated protein)


What test can be done to look for evidence of old optic neuritis? What would be a positive result?

visual evoked potentials

increased latency of the P100 wave on the affected side


Describe the pathology you'd see in an acute MS lesion.

a sharply defined area of myelin loss with relative preservation of axons and associated signs of perivascular inflammation (macrophages, lymphocytes, plasma cells and reactive astrocytes)


Describe the pathology you'd see in an old MS lesion.

axon loss and extensive glial proliferation


Acute relapses of MS are usually treated with what?

high dose corticosteroids (IV methylprednisolone, often followed by an oral prednisone taper)

this shortens the duration of symptoms, but probably does not affect the long-term outcome


What are the main agents used to chronic treatment of MS as immune-modulating agents?

beta-1a interferon (Avonex-what my lady is on), beta-1b interferon, glatiramer acetate (copaxone), natalizumab, fingolimod


What are some potential side effects of the interferons?

flu-like smptoms, depression, injection site reaction, leukopenia and reversible transaminitis (so check LFTs)


If a patient begins to not respond to the interferons, what has likely happened?

they probably developed neutralizing antibodies


Natalizumab is a monoclonal antibody against what and how does it work?


prevents lymphocytes and monocytes from crossing the blood-brain barrier


Natalizumab is probably more effective than the interferons and glatiramer, but why don't we use it right away?

it's associated with a small but significant risk of developing progressive multifocal leukoencephalopathy after infection with JC virus

this is untreatable and often fatal


How does fingolimod work?

it's a mixed agonist/antagonist of the sphingosine-1p1 receptor

it sequesters autoreactive T-cells inside the lymph nodes so they can't get out and wreak havoc

(first oral med!)


What are the most serious side effects of fingolimid?

bradycardia and heart block, so monitor with ECG during first administration


A monophasic illness that looks like MS after an antecedent viral infection or vaccination is likely what?

acute disseminated encephalomyelitis


Although ADEM can look a lot like MS, what are some signs/symptoms that are more suggestive of ADEM?

lesions are multiple and more patchy, bilateral and confluent than in MS

ADEM lesions have a predilection for posterior cerebral hemispheric WM

behavioral and cognitive abnormalities are more common


What will CSF analysis show in ADEM?

more marked lymphocytic pleocytosis than in MS

elevated protein

rarely oligoclonal bands


What are the two components of neuromyelitis optica (Devic disease)?

transverse myelitis and optic neuritis


True or false: the transverse myelitis and optic neuritis need to occur at the same time to get the diagnosis of neuromyelitis optica.

false - they can occur simultaneousl or there may be a delay (sometimes even 1-2 years)


How do you confirm a diagnosis of neuromyelitis optica?

antibodies to the aquaporin-4 channel


What is the treatment for neuromyelitis optica?

steroids (duh)

also more aggressive measures like chemo and plasmapheresis


What is the general prognosis for neuromyelitis optica?

generally poor with patients typically developing paralysis and blindness in the long term


Going back to progressive multifocal leukoencephalopathy....besides MS patients on Natalizumab, who gets this?

patients with AIDS, leukemia, lymphoma, use of immunosuppressants and generally any immunocompromised state


What cell does the JC virus infect to cause PML?



What is the mortality rate for PML

50% (yeeks)


What leukoencephalopaty develops in the context of rapidly developing hypertension and eclampsia or due to immunosuppressants used to prevent organ transplant rejection?

Posterior reversible encephalopathy syndrome (PRES)


How will PRES present?

acute confusional state and cortical visual loss (blindness with preserved pupillary reactivity)


Is PRES always reversible?

nope - can result in coma or death