Multiple Sclerosis Flashcards
(49 cards)
What is the main pathological process which causes multiple sclerosis?
Demyelination and inflammation of the neurones within the CNS
Disease of white matter in the CNS
What are the risk factors associated with MS?
Genetic inheritance Female sex Temperate climates Vitamin D EBV
Describe what the age of exposure of risk refers to in someone’s risk of getting MS?
For example;
If someone was brought up in a a temperate climate i.e. scotland but moved to a more tropical / less temperate climate when they were >10 yrs old then they would still carry the risk for MS
However if they were born in scotland but moved to a more temperate climate before the age of 10 then they wouldn’t carry the risk that is associated with somewhere like scotland that has a temperate climate
What is the distrubution/prevalance of MS in females compare to males?
Females:male 2-3:1
Describe the pathophysiology of the demyelination in MS.
Autoimmune process
Activated T cells cross the BBB causing demyelination resulting in acute inflammation of the myelin sheath
Results in loss of function
Repair/recovery of function
Post inflammatory neurones may have deficits
What is the initial presentation of MS ?
In majority of cases, patients first present with a relapse - ‘attack of demyelination’ ;
- gradual onset over days
- stabilises within days/weeks
- gradual resolution to complete or partial recovery
What symptoms do patients with MS experience with a relapse?
Optic neuritis
Sensory symptoms
Limb weakness
Brainstem i.e. diplopia, vertigo and/or axtaxia
Spinal cord i.e. Myelitis , dens/weakness, bilateral signs & symptoms and/or bladder & bowel symptoms
Is someone has presents with 1 relapse and recovers from this and doesn’t have another relapse, what is this termed as?
Clinically isolated syndrome (CIS)
They will not be diagnosed with MS because MS is characterised by having acute remitting relapses which show new areas of demyelination
Describe the presentation/symptoms of optic neuritis.
Subacute visual loss Pain on moving the eye Colour vision disturbed Initial swelling of optic disc in one eye Relative afferent pupillary defect
Usually resolves over weeks
Optic atrophy seen later
Describe the presentation of someone with a brainstem relapse of MS.
Cranial nerve involvement
Involves the pons = internuclear ophalmoplegia
Involves the cerebellum = vertigo, nystagmus, ataxia
UMN signs
Sensory involvement
What is myelitis?
Inflammation / demyelination of the spinal cord
Commonly occurs as a relapse of MS
What si the presentation of myelitis?
Sensory loss often with band of hyperaesthesia
Weakness / UMN changes below level of demyelination
Bladder and bowel involvement i.e. incontinence
May be painful
As MS progresses, patients accumulate signs and symptoms which become debilitating even in between relapses.
What are some of these signs and symptoms?
Fatigue Temperature sensitivity Sensory loss Stiffness or spasms Balance Slurred speech Swallowing problems Bladder & bowel symptoms i.e. incontinence Diplopia / oscillopsia / visual loss Cognitive - dementia and emotional liability
What investigations can be carried out to diagnose and investigate MS?
MRI Lumbar puncture (oligoclonal bands) Chest X ray Bloods (detect any other inflammatory conditions present) Visual / somatosensory evoked response
What is the name of the clinical and MRI criteria used to diagnose MS?
MRI = Mac Donald criteria Clinical = poser criteria
What is the correlation between the number of lesions found on patients MRI scan of demyelination and the amount of relapses they have?
For every approx 10 lesions a patient experiences 1 relapse
What do you have to be aware of when using an MRI scan to assess someone’s severity/diagnosis of MS?
Sometimes the the scan and a patients symptoms don’t correlate.
Someone could have many lesions on MRI but not experience as much / so severe symptoms as someone who has less lesions on a scan
Why are blood tests carried out when investigating someone with suspected MS?
To investigate if there is any other inflammatory process occurring
Why is a lumbar puncture carried out when investigating someone with suspected MS?
LP identifies if there are any oligoclonal bands in the CSF and compares them to see if there is present in the serum(blood)
Because only in MS are oligoclonal bands found in CSF but not blood
What are the differential diagnoses of MS?
Acute disseminated encephalomyelitis (ADEM) Other autoimmune conditions i.e. SLE Sarcoidosis Vasculitis Infection i.e. Lyme disease, HTLV-1 Adrenoleucodystrophy
What are the 3 types of MS?
Relapsing remitting (RRMS) Secondary progressive (SPMS) Primary progressive (PPMS)
What is the course of MS like in secondary progressive MS?
They first have a relapse, then completely heal back into remission.
They then experience another relapse but many years later.
After the 2nd relapse they don’t fully heal in remission and progressively get worse
What is the course of MS like in primary progressive MS?
They first present with a relapse but don’t fully recover from it
From then on they continue to get worse and never recover
What is permanent persistive disability over time due to?
Axonal loss (nerve cell loss)
