Multiple Sclerosis Flashcards
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)
Which factors indicate a ‘good’ prognosis?
Female
Presents with optic neuritis
Long interval between 1st and 2nd relapse
Few relapses in 1st 5yrs
What factors indicate a ‘bad’ prognosis?
Male
Older age
Multifactorial symptoms and signs
Motor symptoms and signs
What type of MS often presents in the 5th / 6th decade?
Primary progressive (PPMS)
What are the main symptoms in primary progressive MS?
Bladder / bowel symptoms
What is the distribution between male and female regarding primary progressive?
Male female 1:1
What is characteristic about the pathophysiology of neuromyelitis optic spectrum disorder?
Aquaporin-4-antibodies
What are some of the disease modifying treatments for MS?
S/c or i/m injections:
- beta interferon
- glatiramer acetate
Oral treatments:
- teriflunomide
- dimethyl fumarate
What are some of the side effects of the disease modifying treatments for MS?
Immunosuppression
Flu like symptoms
Injection site reaction
Abnormalities of blood count and liver function
Daily/weekly injection
Not a cute
No affect on progression of disease - only help by reducing no of relapses or speed of recovery from relapses
What are the benefits of the disease modifying treatments for MS?
Reduce relapse rate by 1/3rd
Immunosuppression is one of the main consequences of aggressive treatment of MS. What can this leave patients at risk of?
Progressive multifocal leukoencephalopathy (PML)
What causes progressive multifocal leukoencephalopathy ?
JC virus
Can be contracted in MS patients who are immunosuppressed due to aggressive treatments
What aggressive treatments for MS can cause patients to become immunosuppressed?
Natalizumab
Dimethyl fumarate
Fingolimod
What are some of the treatment that are given for symptomatic treatment of spasticity in MS?
Anti spasmodic
Muscle relaxants
Physio therapy
What are some of the treatment that are given for symptomatic treatment of dysaethesia in MS?
Amitriptyline
What are some of the treatment that are given for symptomatic treatment of urinary complications/problems in MS?
Anticholinergic/bladder stimulator
Catheterisation
What are some of the treatment that are given for symptomatic treatment of vision/ oscillopsia symptoms in MS?
Carbamazepine
What are some of the treatment that are given for symptomatic treatment of difficulties in speech and swallowing in MS?
SALT
If a patient with MS is on aggressive treatment, what are they at risk for and how do you test for this?
Progressive multifocal leukoencephalopathy (PML)
- Annual MRI
- JC antibody status
What is the difference between neuromyelitis optics spectrum disorder and MS?
Neuromyelitis is an ‘attack’ of the optic nerve and the spinal cord and presents with optic neuritis and myelitis.
Whereas MS is an ‘attack’ on the whole of the CNS
What is diagnostic of neuromyelitis optic spectrum disorder?
Aquaporin 4 antibodies
How do you treat an acute relapse of optic neuromyelitis spectrum disorder?
Oral prednisolone
Symptomatic treatment
What is internuclear ophthalmoloplegia?
CN III palsy in which the patients affected eye fails to adduct showing a contralateral gaze
In a patient with MS, on MRI where is the most common site to find lesions?
periventricular area
near ventricles
what does visual evoked potentials assess?
they look for evidence of previous demyelination of the optic nerve
what is the medical term for muscle disease resulting in muscle weakness?
myopathy
