Multiple Sclerosis Flashcards
What is MS?
Acquired, chronic, immune-mediated, inflammatory disease of the CNS (can affect brain, brainstem, + spinal cord)
What do the inflammatory processes in MS cause pathophysiologically?
Areas of demyelination (damage to white matter), gliosis (scarring), + neuronal damage throughout the CNS.
Describe the epidemiology of MS
F > M (3:1)
Age of onset: 20-40y
More common at high latitudes
What causes MS?
UNKNOWN
Acute then chronic inflammation precipitated by abnormal response to environmental triggers in genetically pre-disposed
Immune-mediated damage to myelin sheaths results in impaired axonal conduction.
List 2 risk factors for MS
FH
Female
List 3 types of MS
Relapsing-Remitting (RRMS)
Primary Progressive (PPMS)
Secondary Progressive (SPMS)
Describe RRMS
Most common, 85% have RRMS at onset
Attacks (1-2 months) with almost complete recovery between attacks
Describe SPMS
gradual accumulation of disability after initial relapsing course
2/3 of RRMS progress to SPMS
Describe PPMS
Steady progression + worsening of disease from the onset, without remissions.
~10-15% of MS
Define ‘relapse’ of MS
Onset of new Sx, or worsening of pre-existing Sx.
Attributable to demyelinating disease.
Lasting >24 h
In absence of infection, or any other cause.
After a stable period of at least a month.
What do symptoms depend on in MS?
Site of inflammation
List the 4 most common initial presentations of MS
Optic neuritis
Transverse myelitis
Cerebellar-related Sx
Brainstem syndrome
Describe optic neuritis
Unilateral deterioration of visual acuity + colour vision
Pain behind eye + on eye movement
Other than optic neuritis, what are the possible visual manifestations of MS
Optic atrophy
Uhthoff’s phenomenon
Internuclear ophthalmoplegia
What is Uhthoff’s phenomenon?
Worsening of vision following rise in body temperature
Describe fundoscopy in optic neuritis in MS
Often normal but disc may appear pale or swollen.
May be RAPD
What is transverse myelitis?
focal inflammation within the spinal cord
Sensory Sx (such as paraesthesia) or Motor Sx (such as weakness)
below level of inflammation
Typically develop over hours or days.
How may transverse myelitis manifest?
Tight band sensation around the trunk at level of inflammation
Lhermitte’s phenomena
Urinary Sx: urgency, frequency, retention
Focal muscle weakness + reduced sensation below affected spinal level
Muscle tone initially reduced
What is Lhermitte’s phenomena?
Shock-like sensation radiating down the spine + into limbs induced by neck flexion
Describe cerebellar-related symptoms that may arise in MS
Ataxia
Vertigo
Clumsiness
Dysmetria
Describe how brainstem syndromes may manifest in MS
Ataxia
Eye movement abnormalities
Bulbar muscle problems resulting in dysarthria/ dysphagia
What are 3 sensory symptoms of MS?
Pins + needles
Numbness
Burning
What 6 general signs are seen on examination in MS?
Sensory: Paraesthesia
Motor: Spastic weakness most commonly seen in legs
Cerebellar: Limb ataxia (intention tremor, past-pointing)
Urinary frequency/ incontinence
Sexual dysfunction
Cognitive impairment
What is diagnosis based on in MS?
Finding 2 or more CNS lesions with corresponding Sx, separated in time + space (McDONALD CRITERIA)
Only a consultant neurologist should make a dx of MS.
