Demyelinating Diseases - MS Flashcards
3 Things MS is a Disease of (and major point)
Neurons, axons, and (most noticeably) myelin - so primarily affects white matter, but gray matter is also affected
Difference b/w MS and Leukodystrophy
MS is acquired
Geographical Distribution of MS
Twice as likely North of 37th parallel. If you’re born in an area there, the later you move S the more likely you’ll develop it
Significance of Oligo Promiscuous Myelination
Destroy 1 oligodendrocyte, get a visible plaque
Post-Capillary Venules
Often in center of demyelinated spot, so you get mononuclear immune cells going into CNS
Damage Mediator in MS
Macs
Dawson’s Fingers
Fingerlike projections of demyelination extending from corpus callosum - sure sign of MS
Basis of MS Treatment
Systemic immune modulation (not suppression). Don’t worry about BBB-ability of drugs, just modulate peripherally and it’ll affect centrally too
Main Pathogenesis of MS
Impairment of NoR - always symptomatic, MRI often normal
4 Impacts of Demyelination on Function
Cessation of all conduction - acute attack
Anomalous conduction b/w axons
Slowing of conduction
Spontaneous generation of impulses - L’Hermitte’s phenomenon
L’Hermitte’s Phenomenon
Plaque in neck, when you bend feel shock bc of spontaneous impulses
Conduction Regeneration
Might regain via basic saltatory conduction, but makes it more susceptible to heat bc Na channels open and close faster
Clincally Isolated Syndrome
Initial presentation of MS consisting of: optic neuritis, brain stem events (MLF problems and shit), and incomplete transverse myelitis (rising tingling)
Radiologically Isolated Syndrome
See accdientally from MRI, but asymptomatic
3 Clinical Courses of MS
Relapsing Remitting Disease - attack, goes away, returns less severe
Secondary Progressive Disease - about 50% of RR becomes, slowly gets worse
Primary Progressive
