Multiple Sclerosis (MS) Flashcards
MS is a chronic and progressive a_____ condition involving d_____ in the CNS
autoimmune
demyelination
In MS, what does the immune system attack?
Myelin sheath of the myelinated neurones
True or false: MS typically presents in males over 50
False
Typically in young adults and more common in women
What cells wrap around the axons, providing the myelin sheath in the CNS?
Oligodendrocytes
What cells wrap around the axons, providing the myelin sheath in the PNS?
Schwann cells
Does MS affect the CNS or PNS?
CNS (oligodendrocytes)
Inflammation and immune cell infiltration causes damage to the myelin affecting…
the electrical signals moving along the neurones
In early disease of MS, r______ can occur and the symptoms can resolve
remyelination
In later stages of MS, re-myelination is incomplete and the symptoms gradually become more p____
permanent
MS lesions can vary in location meaning the affected sites and s____ change over time. The lesions disseminate in time and space.
symptoms
What causes MS
unclear
May be influenced by:
multiple genes
EBV
Low vitamin D
Smoking
Obesity
At first presentation of MS, how long do symptoms tend to present
last days to week and then improve
What is a common presentation of MS?
Optic neuritis
Demyelination of optic nerve causing unilateral reduced vision developing over hours to days
What are key features of optic neuritis (common symptom of MS)
Central scotoma (enlarged central blind spot)
Pain with eye movement
Impaired vision colour
Relative afferent pupillary defect (affected eye constricts more with light in contralateral eye than its own pupil)
Can’t see colour red properly
What type of hypersensitivity is multiple sclerosis?
Type 4
What are symptoms of MS?
Optic neuritis
Internuclear ophthalmoplegia
Parasthesia
Blurred vision
Uthoff’s phenomenon (symptoms exacerbated with heat eg after shower)
Brainstem signs
Sensory signs
UMN sign
Lhermitte phenomenon
Charcot neurological triad
What is internuclear ophthalmoplegia?
lateral gaze is impaired due to damaged medial longitudinal fasciculus
What is Lhermitte phenomenon?
Electric shock sensation on flexion of neck due to stretching demyelinated dorsal column
What makes up the Charcot neurological triad?
Dysarthria (staccato speech)
Nystagmus (uncontrolled eye movements)
Intention tremor (worsens before reaching target)
What criteria is used to help diagnose MS?
McDonald Criteria
What does the MacDonald criteria state for diagnosing MS?
2 or more attacks disseminated in time (separate events) and space (different part of CNS affected)
How is MS diagnosed?
MRI of brain and cord:
shows dissemination in space (changes in white demyelination) and time (contrast shows how long been there)
MS results in delayed c_____ speeds
conduction
What may a lumbar puncture show for someone with MS?
oligoclonal IgG bands
How do you treat acute MS (during episode)?
IV methylprednisolone
What prophylaxis is used for MS?
B interferon (DMARD, biologic)
Where may a lesion be to result in sensory ataxia?
Dorsal column
What is the most common pattern when first diagnosed with MS?
relapsing-remitting
What are symptomatic treatments for MS?
Exercise to maintain activity and strength
Amantadine or SSRIs for fatigue
Amitriptyline for neuropathic pain
SSRI for depression
Antimuscarinic meds for urge incontinence
Gabapentin (anticonvulsant) for spasticity
Gabapentin for oscillopsia (unstable vision)
