What is Multiple sclerosis?
a chronic and progressive autoimmune condition where the central nervous system becomes demyelinated
What does the immune system do in multiple sclerosis?
it attacks the myelin sheath of myelinated neurons, making conduction slower
What is the typical patient of MS?
a woman under 50
What does myelin do and where is it?
it covers the axons of neurones and makes electrical impulses travel faster
What cells provide myelination in the CNS?
oligodendrocytes
What cells provide myelination in the PNS?
Schwann cells
What can happen in early MS disease?
re-myelination can occur
What is usually found when diagnosing multiple sclerosis?
That there are often demyelinating lesions in the whole CNS that aren’t causing symptoms
What can happen in late stage MS disease?
re-myelination is incomplete and symptoms become permanent
What is unique about the MS lesions?
they are disseminated in time and space meaning the lesions vary in location so the signs and symptoms change overtime
What are the causes of MS?
Unclear but may be due to:
- multiple genes
- EBV
- low vitamin D
- smoking
- obesity
What is the onset of the presentation of MS?
- symptoms usually progress over more than 24 hours
- they tend to last days to weeks from the first presentation then improve
What are the main symptoms?
present in many ways- depending where the lesion is
- optic neuritis
- eye movement abnormalities
- ataxia
What are the focal neurological symptoms of MS?
- incontinence
- Horner syndrome
- facial nerve palsy
- limb paralysis
What are the focal sensory symptoms in MS?
- trigeminal neuralgia
- numbness
- paraesthesia (pins and needles)
- Lhermitte’s sign
How do you diagnose MS?
- clinical picture
- MRI scans showing spatially distributed gadolinium-enhancing areas
- lumbar puncture- oligoclonal bands in CSF
What is the management of MS?
- relapses treated with steroids
- disease modifying therapies to induce long term remission
- symptomatic management eg modanifil for fatigue
Disease patterns: clinically isolated syndrome
first episode of demyelination action and neurological signs and symptoms
Disease patterns: relapsing and remitting MS
most common- episodes followed by recovery
Disease patterns: secondary progressive MS
was relapsing and remitting disease but now there is a progressive worsening of symptoms with incomplete remissions
Disease patterns: primary progressive MS
worsening disease and neurological symptoms from point of diagnosis without relapses and remissions
What features lead to a worse prognosis of MS
- male sex
- older age
- motor symptoms at onset
- early relapses
- many lesions on MRI
- axonal loss
