Multiple Sclerosis Flashcards
What is MS?
Disease of CNS characterized by occurrence of focal areas of inflammation with demyelination. Must document two separate areas of CNS involvement
What are the 3 major versions of MS?
- Primary progressive, a slow but steady worsening of the disability from the onset, with no remissions or relapses, worsening year to year.
- Relapsing-remitting, acute episodes of worsening neurologic function followed by complete or partial recovery with no progression between relapses
- Secondary progressive, disease course after initial relapse when progression of disability occurs between additional clear-cut relapses.
What is the mean age of onset, and the median age of onset? Which gender is more affected? What race and geographic location is more affected?
Mean age is 28, median age is 22. 3/4 of MS patients are female. 95% of MS patients are caucasian. Geographically restricted to northern Europe, US, Canada, Australia, New Zealand.
What is the risk of an identical twin having MS if their twin has it?
About 30%.
How does vitamin D influence MS?
Higher serum vitamin D levels have been associated with a lower rate of getting MS
Where do MS lesions cluster?
Around the ventricles and follow the post-capillary venule distribution.
What does the histology study of acute lesions show?
Inflammatory cells clustered in perivascular spaces
What is Uhthoff’s phenomenon?
The worsening of symptoms with heat
What is the time course for exacerbations of MS symptoms?
Hours/days (so not vascular, which occurs over seconds to minutes)
What are the common sensory symptoms of MS?
Decreased or altered sensation, loss of pain, loss of vibration and proprioception (whichare more common)
What are the vision symptoms of MS?
Monocular visual loss (optic neuritis) or double vision (diplopia)
What are the motor symptoms of MS?
Weakness of one limb, both legs, or half of the body. Upper motor neuron signs are common.
What are the brainstem symptoms of MS?
Spinning (vertigo), dysarthria, dysphagia, facial weakness. Trigeminal neuralgia is also common. Nystagmus is also often seen
What are the 3 signs that are so often associated with MS that MS should be on the differential when found?
Optic neuritis, internuclear ophthalmoplegia, and partial myelitis
What is optic neuritis?
presenting with unilateral visual loss and pain with eye movement. Often with an afferent pupillary defect. Optic pallor often develops as well
What is internuclear ophthalmoplegia?
Results from demyelination of the MLF, resulting in an inability to adduct the eye to the side of the lesion. Nystagmus of the contralateral abducting eye may also occur. Medial rectus function spared.
What is partial myelitis?
Focal demyelination of spinal cord that causes sensory and motor abnormalities localized to a specific spinal cord level
What is transverse myelitis?
Total demyelination across entire spinal cord
What is Devic’s disease?
Transverse myelitis with optic neuritis; also known as neuromyelitis optica.
What do CT scans show with MS? What do MRIs show?
CT scans are normal in MS. MRI is almost always abnormal and demonstrates MS lesions
What is Dawson’s fingers?
periventricular lesions that are ovoid with perpendicular orientation to the lateral ventricles
What are the CSF findings in MS?
- Total spinal fluid protein decreased to below 50, always below 100
- Increased intrathecal synthesis of IgG and/or clusters of polyclonal IgG
What other diseases can mimic MS?
Sjogren’s and sarcoidosis. Infections such as borrelia, syphilis, JC virus, and retroviruses. Vitamin B12 deficiency
What is a consideration with MS patients and surgery/anesthesia?
They do not trigger attacks, but the repaired nerves are more reliant on sodium channels, so sodium channel blockers may be more potent and last longer
Name factors that seem to exacerbate MS symptoms (2)? What improves MS symptoms (1)? What seems to have no effect (2)
Exacerbate: Heat and infections (and possibly vaccines)
Improve: pregnancy
No effect: trauma and surgery
