Term
| Describe the aetiology of MS |
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Definition
Exact cause unkown.
1. Familial link - HLA A3/B7/D2
incs risk if 1st degree relative
2. abnormal immune response to virus. Assoc with viral infection in teenage years. abnormal cytokine response.
3. Assoc with inc consumption of animal fats. |
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Term
| Decribe the epidemiology of MS |
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Definition
Females>Males
Age of onset = 20-45
Incs prevalence further away from equator |
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Term
| What is the pathology of MS? |
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Definition
Plaques of demeylination in CNS.
Acute relapse caused by inflammation - local relase of NO by monocytes. Nueronal fibre damage - if serious = axonal degeneration.
Remission when inflammation ceases. |
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Term
| Is functional recovery possible in MS? |
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Definition
| Yes - due to increased Na+ channels in axon. BUT NO remyelination. |
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Term
| give the 2 main types of MS. |
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Definition
| relapsing remitting and Primary progressive |
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Term
| how does relapsing remitting MS usually present? |
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Definition
1. Optic neuropathy
2. Spinal Cord Lesion
3. Brainstem demyelination |
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Term
| What happens in optic neuropathy in MS? |
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Definition
Sudden onset of blurred vision. - unilateral
Anything from looking through frosted glass to complete mononuclear field loss.
Occular pain common
Resolves in 1-2months.
Optic neuritis = at nerve head - disc inflammation (papillitis)
Retrobulbar neurop = behind nerve head no signs on fundoscopy.
Afferent pupillary defect (dec motor) = dec pupil constriction. |
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Term
| What happens in spinal cord lesions? |
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Definition
spastic paralysis
difficulty walking
sensory disturbances
urinary symptoms = PSNS lesion in S2-S4
Lhermittes sign = electric shock when flex spinal cord. |
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Term
| what happens in brainstem demyelination. |
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Definition
limb signs if corticospinal tract involved.
acute onset of dysphagia, diplopia, facial weakness/numbness, vertigo.
charcot's triad = nystagmus/intention tremor/scnning dysarthria. |
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Term
| What investigations would you do if you suspect MS? |
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Definition
neurological examination
MRI of brain and SC - plaques visible.
CSF sample = oligoclonal bands of IgG. |
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Term
| How are acute relapses of MS managed? |
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Definition
| High dose of short acting corticosteroid. e.g IV methyprednisolone. |
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Term
| How are relapses of MS prevented? |
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Definition
Beta-interferon - immunosuppressive. Prevents T-cell maturation and corssing BBB. s/e = flu-like.
Azathioprine - supresses BM
glatramir acetate = prevents interaction between myelin basic protein and T lymphos. |
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Term
| How are the associated signs and symptoms of MS managed? |
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Definition
Fatigue = amantadine
spasticity = Baclofen
Tremor = Beta-blockers
Incontinence = Anti-Ach/cathaterisation
Bowel = fleet enemas/lactulose
Pain = simple analgesics/ NSAIDs |
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