Multiple Sclerosis Flashcards
Dysmyelinating disease
A disease where myelin isn’t formed correctly in the first place (generally due to inherited metabolic disorders).
Demyelinating disease
A disease where the myelin sheath around a neuron degenerates. This happens in multiple sclerosis, where the myelin sheath is destroyed, but the axon remains intact.
Adrenoleukodystrophy
Malformation of myelin (dysmyelinating disease)
Tay-Sachs
Dysmyelinating disease where myelin by-products accumulate in neurons
Clinical presentation of multiple sclerosis
Relapsing neurologic symptoms and progressive functional impairment. Can cause monocular vision loss, CN deficits, sensory/motor impairments, imbalance
Common early features of MS
Motor weakness, ataxia, double vision. Can be diagnosed with MRI.
Charcot’s original triad of MS
Intention tremor, nystagmus, scanning speech (points to cerebellar involvement)
Optic neuritis
Degeneration of optic nerve. Common presenting feature. Partial or complete vision loss in one eye. Unilateral eye pain that is exacerbated upon movement. Sometimes present with a scotoma.
How many patients with optic neuritis will go on to present with MS?
About 1/2
Clinical patterns of MS
Relapsing remitting (stay at one level with occasional deficits, return to baseline) Secondary progressive (most people come from relapsing remitting to this form, where deficits don't resolve completely) Primary progressive, no relapses, just progressively getting worse.
Can lesions occur without outward symptoms?
Definitely.
Most common disease course?
Relapsing-remitting, which then turns into secondary progressive (usually within 10 years).
Clinically isolated syndrome
A singular sclerosis that will develop into multiple sclerosis.
Who are MS patients?
Women 2x more likely, age of onset 20-40
Genetic risk of MS?
Yes, first second and third degree relatives all at risk.
What does multiple sclerosis actually mean?
Disease activity at multiple points in time distributed across regions of the CNS.
Is there a diagnostic test?
No, clinical diagnosis in conjunction with an MRI.
What is a good predictor of progression to MS after first attack?
Number of lesions seen on MRI, >3 = 51%
Immunologic cause of MS
TH1 cells activated by a virus (or something), self-reactive TH1 cells enter brain and mistake myelin for antigen. Tissue damage by pro-inflammatory cytokines and edema.
CSF in MS?
IgG synthetic rate elevated, IgG oligoclonal bands elevated upon electrophoresis.
Goals of treating MS
Treat relapses and exacerbations with high dose of IV steroids, some disease modifying agents, also treat symptoms of spasticity, pain, fatigue.
Problems with treating MS?
Disease modifying agents are only partially effective.
Uhthoff’s phenomenon
Sudden onset of neurological dysfunction as a result of elevated body temperature.
