Multiple Sclerosis Flashcards
Mean age of onset of multiple sclerosis?
30 years
Majority of people between 20 - 40 years when diagnosed
What is the pathophysiology of MS?
It is an immune mediated inflammatory disease that attacks myelinated axons in the CNS
What sort of disease progression does MS tend to follow?
A relapse-remitting pattern
Onset of symptoms over days, stabilises over days - weeks, gradually resolves (not always completely), then relapses in a few months/years
What are some common ways in which MS relapses?
- Optic neuritis
- Sensory loss
- Limb weakness
- Brainstem issues (diplopia/ataxia)
- Spinal cord issues (bilateral motor & sensory symptoms, bladder involvement)
What is optic neuritis? Symptoms?
- Inflammation of the optic nerve
- Subacute visual loss
- Pain moving eye
- Colour vision disturbed
Common clinical sign of optic neuritis?
- Abnormal pupillary reflex in one eye
- Usually only one eye affected, so do pupillary constriction test and one eye will only cause partial constriction of the pupils compared to the other
Ways in which brainstem relapse of MS can present?
- Cranial nerve issues
- Pons: internuclear ophthalmoplegia (affected eye can’t adduct)
- Cerebellum: vertigo, nystagmus, ataxia
- UMN signs in limbs
- Sensory loss
What is nystagmus?
- Normally when the head moves the semicircular canals of the ears sense this movement and tell the brain to rotate the eyes the opposite way so that gaze can be fixated on an object
- Nystagmus occurs when the semicircular canals are being activated when the head is not moving, causing the eyes to “dance about.” Can cause visual issues
What is myelitis and what are some symptoms it can cause?
- Myelitis is inflammation of the spinal cord, can be transverse (both sides of a section of SC) or partial
- Band of hyperaesthesia (excessive sensitivity) at sensory level
- Weakness/UMN changes below level of demyelination
- Bladder & bowel involvement
Pathophysiology of the demyelination process?
- Autoimmune: activated T cells cross BBB
- Loss of function, repair, recovery of all/some function
- Post inflammatory gliosis (glial cell proliferation)
- Appears as plaques/lesions on MRI
What can cause MS relapse?
- Underlying infection in 25-30%
- Fewer relapses in pregnancy, increased risk in first 3 months post-partum
What causes persistent disability in MS? How is this diagnosed?
- Axonal loss causes persistent disability
- Seen as black holes on MRI and later as cerebral atrophy
What happens during the progressive phase of MS?
Accumulation of symptoms and signs, body can’t recover before onset of the next attack
What are some clinical signs to look for in examination of MS patient?
- Afferent pupillary defect
- Nystagmus or abnormal eye movement
- Cerebellar signs
- Sensory signs
- Weakness
- Spasticity
- Hyperreflexia
- Plantars extensor (+ Babinski - toe up when foot brushed w blunt object)
What are the three types of MS and description of their progression?
- Relapsing-remitting (85%): Symptoms, then resolution, then relapse a while later. Continuous
- Secondary progressive: Begins like RR, then one relapse initiates progressive disease that doesn’t resolve
- Primary progressive: progressive from onset
When does primary progressive MS tend to present?
Often presents in 5th and 6th decade
Often poor prognosis with spinal and bladder symptoms being common
What are the criteria used to diagnose MS?
- Clinical based diagnosis: Posers Criteria
- MRI based: Macdonald Criteria
What compound can be administered to a patient and highlights plaques/tumours on MRI scan?
Gadolinium
Some possible Differential Diagnoses for MS?
- Acute Disseminated Encephalomyelitis
- Autoimmune conditions (eg. SLE)
- Sarcoidosis
- Vasculitis
- Infection (eg. Lyme disease, HTLV-1)
- Adrenoleucodystrophy
Best investigation for MS?
Other investigations?
- MRI is the best
- Lumbar puncture: oligoclonal (Ig) bands in CSF?
- Bloods: exclude other inflammatory conditions
- CXR
How does MS tend to progress for patients?
- VERY variable
- 25% of MS never affects activities of daily living
- 15% causes severe disability quickly
- 25% will need a wheelchair at some point
What are the treatment approaches taken to manage MS?
- Treatment of relapses
- Disease modifying treatment (reduce relapse rate, not a cure. Doesn’t slow progression)
- Lifestyle changes and symptomatic treatment
- Vaccines etc. to reduce infection probability
How is an acute relapse of MS treated?
- LOOK FOR UNDERLYING INFECTION
- IV/oral prednisolone (anti-inflammatory steroid)
- Symptomatic treatment
What are the first line disease modifying treatments for MS?
Subcutaneous/intramuscular injections:
- Beta interferons
- Glatiramer acetate
Oral treatment:
- Teriflunomide
- Dimethyl Fumarate
Second line disease modifying agents for MS?
- Natalizumab
- Fingolimod
- Cladribine
- Ocrelizumab
- Alemtuzumub
Common symptomatic treatments for MS patients?
- Spasticity: muscle relaxants, antispasmodics
- Dysaesthesia (discomfort when touched): amitriptyline
- Urinary: anticholinergics, bladder stimulator/catheter
- Constipation: laxatives
- Sexual dysfunction: sildenafil
