Multiple Sclerosis Flashcards
What part of the CNS does MS attack?
the myelin of the white matter
Is MS considered an upper or lower motor neuron lesion?
upper
MS is characterized by reactive gliosis, what 2 things does this lead to?
- scarring
- disturbances in the transmission of action potentials
MS usually affects what age group?
young adults (usual onset less than 55)
MS is most common in what type of people?
Those with western European lineage
Describe MS incidence in reference to the equator
Usually affects people who reside in temperate locations away from the equator
No population that is considered a high risk of developing MS lives within __ degrees north or south of the Equator
40
What genetic component appears to be associated with the susceptibility of MS?
the alleles of interleukin-2 and interleukin-7 alpha receptors
Where are the 2 alpha receptors located?
on the cell membranes of B and T lymphocytes
What are the 5 initial signs and symptoms of MS?
- Weakness
- Numbness
- Optic neuritic diplopia (double vision)
- Dysequilibrium
- Sphincter disturbance (urinary urgency)
What 3 UMN signs are found in patients with MS?
- Babinski sign
- Hyperreflexia
- Spasticity
What are the 4 types of MS?
- Relapsing-remitting MS (RRMS)
- Secondary progressive MS (SPMS)
- Progressive-relapsing MS (PRMS)
- Primary Progressive MS (PPMS)
What type of MS is the most common?
relapsing-remitting
Relapsing-remitting affects nearly __% of all patients
70
What is relapsing-remitting MS characterized by?
Increases in neurological dysfunction (relapse), followed by periods without disease progression (remission) in which the patient can achieve full recovery
__% of patients with RRMS go on to develop secondary progressive MS
80
Describe SPMS
The relapse-remitting course is followed by progression of symptoms with or without relapses, remissions or plateaus
Describe PRMS
Symptoms get progressively worse from onset and relapses may or may not resolve with full recovery
Primary Progressive MS occurs about __% of the time
10
Describe PPMS
There is continuous worsening of function from onset and there is no distinct relapses or remissions
What are 2 factors that may precipitate or trigger exacerbations?
- infection
- pregnancy
What imaging technique is most useful for diagnosing MS?
MRI
What do T1-weighted MRIs show?
- hypointense (“black holes”) areas that represent axonal damage
- hyperintense (bright) lesions
What can Gadolinium-enhanced T1-weighted highlight?
inflammation with breakdown of the blood-brain barrier, which helps identify new lesions
What do T2-weighted MRIs display?
the total number of lesions
What do lesions look like on a T2-weighted MRI?
high signal intensity areas
Can a definitive diagnosis of MS be based solely on lab findings?
No
Can MS be properly diagnosed if there is evidence of only a single lesion in the CNS?
No
What type of studies have been used to detect subclinical involvement of the visual, brainstem auditory, and somatosensory pathways?
Electrocerebral responses (aka evoked potentials)
What are the 3 CSF abnormalities found in MS patients?
- mild lymphocytosis
- slightly increased protein concentration
- elevated immunoglobulin G (IgG)
Are IgG bands specific to MS?
no
When can MS be diagnosed?
When there are 2 or more different regions of central nervous system (brain, spinal cord, or optic nerves) that have been affected at different times
What special procedure produces high resolution cross-sectional and three dimensional images of the retina, cornea and anterior chamber of the eye?
Optical Coherence Tomography
What do visual evoked potentials do?
Detect impaired transmission along optic nerve pathways
Are impaired VEPs specific to MS?
no, they should be used in collaboration with laboratory and clinical symptoms
Under what 2 circumstances is imaging diagnostic of MS?
- if a gadolinium-enhancing lesion is present at least 3 months after an initial clinical event
- if a new T2 lesion is found at any time compared with a baseline scan obtained at least 30 days after initial clinical event
What are the 4 criteria for MRI brain abnormality?
- At least one gadolinium-enhancing lesion or nine T2 hyperintense lesions if no enhancing lesion
- One or more infratentorial (or spinal cord) lesions
- One or more juxtacortical lesions
- At least three periventricular lesions
How many of the 4 MRI abnormalities must be present in order to diagnose?
3 of the 4
In patients with a single clinical event who do not satisfy criteria for MS, a diagnosis of what is given?
Clinically isolated syndrome (CIS)
What are patients with clinically isolated syndrome (CIS) treated?
Beta-interferon or glatiramer acetate therapy to try and delay the progression to MS
What role do medications play in treating MS?
They can limit the recurrence of attacks and slow the progression
__% of patients are without significant disability 10 years after onset
50
What type of therapy is given first?
IV (typically methylprednisolone 1g/day for 3 days)
What role do corticosteroids play in treating MS?
Help to speed up recovery from acute relapses, however the magnitude of recovery shows no difference
What reduces the frequency of exacerbations in patients with relapsing-remitting or secondary progressive MS?
- Indefinite treatment with beta-interferon
- subcutaneous administration of glatiramer
What drug reduces the relapse rate when given intravenously but is also associated with an increased risk of the development of progressive multifocal leukoencephalopathy?
Natalizumab
True or False
Natalizumab can be used in combination with beta-interferon, glatiramer acetate, or other immune-modifying therapies
False
What drug reduces the relapse rate in MS?
Fingolimod
What drug is limited by liver toxicity in some patients?
Teriflunomide
When should Alemtuzumab be used?
if asymptomatic progressive multifocal leukoencephalopathy develops from Natalizumab use
What is an effective FDA-approved drug to treat fatigue associated with MS?
modafinil
What drug is effective at improving timed gait in MS?
dalfampridine
Patients on interferon beta-1a drugs are more susceptible to what kinds of disorders?
depression or suicidal behaviors
What is a common cause of pain in MS?
Musculoskeletal strain and joint malalignment caused by weakened muscles
What has been proven to improve function while lessening disability, and enhancing the patients’ quality of life?
exercise
When should exercise sessions be scheduled and why?
in the morning before fatigue sets in and when core body temp is the lowest
MS patients have been known to only be able to achieve __-__% of their age predicted max HR
75-85
Exercise intensity should be limited to __-__% of peak HR or _–__% of peak VO2
60-75
50-65
What 2 things can help fight off spasticity?
increased flexibility and cryotherapy
Overall what is the basis of physical therapy?
Always be functional and limit fatigue
