Multiple Sclerosis Flashcards
What is MS?
Autoimmune inflammatory disease which attacks myelinated axons in the CNS
How is MS diagnosed?
Neurological symptoms/previous neurologic episode lasting 24 hours
- no evidence of infection/fever/encephalopathy
What are the most common symptoms of MS?
- sensory/motor (tingling/numbness of arms and legs, electric current sensation down back/legs)
- vision problems (blurriness/loss/diplopia)
- slow progressive/subacute motor deficits
What are more rarer symptoms? (less than 5% patients experience)
- bladder dysfunction (frequency, incomplete emptying)
- heat intolerance (heat causes nerves to conduct less efficiently)
- paroxysmal symptoms
- pain movement disorders
- dementia
What are the 3 main characteristics of an MRI on MS?
- Flair lesion spread out in space (in more than 2 CNS areas, lesion in corpus callosum/periventricular/spinal cord)
- Flair lesion occurring at different points in time (development of new lesion after seeing old one)
- Brain atrophy
What is the significance of a lumbar puncture for MS?
- safe if sterile
- atraumatic needle (no damage to dura)
- compares components of CSF to plasma (blood cells, lymphocytes)
- measures neurofilaments
What is the significance of neurofilament amount?
- high = indicates ongoing nerve loss
- protein component of axons
What are the diagnostic criteria of MS?
- dissemination in space (symptoms in more than 1 place in CNS)
- dissemination in time (chronic condition)
- rule out all other diagnoses
What are the types of MS?
- relapsing-remitting (attack occurs then goes back to baselines)
- secondary-progressive (relapse-remitting is not treated so condition becomes progressive)
- primary progressive (patient never relapses and progressively gets worse)
- progressive-relapsing (between relapses disease will get worse)
What are relapses?
Attacks of symptoms
What is the genetic component of MS?
- associated with HLA-DRB1*1501
- not very relevant as offspring chances are relatively low
What are the causes of MS?
relatively unknown:
- viral infection of neurons
- mitochondrial dysfunction
- release of heat shock
What is the pathology of MS?
- axons still present but no myelin around them
Which cells are involved in MS?
- neurons
- astrocytes
- oligodendrocytes
- microglia
What are the 4 types of lesions?
- pre-active lesion (activated microglia and myelin loss)
- active lesion (lymphocyte infiltration around vessels)
- chronic active lesion (lymphocyte spread out around lesion, macrophages engulf myelin and sit on lesion edge)
- chronic inactive lesion (remyelination attempt however already significant enough demyelination and axon loss = astrocytic scar)
